| Platelets are the smallest nucleate cells seen in normal peripheral blood. | View Page |
| Cellular Immunity Cellular immunity includes delayed hypersentivity reactions, graft rejection, graft-versus-host reactions, defense against intracellular organisms, and probably defense against neoplasms.Cellular immunity is mediated by lymphocytes which we call T-cells.T-cells are so named because they are dependent on the thymus for their production and development.The majority of T-cells are long-lived with an average lifespan of 4.4 years, but it is known that some survive for as long as 20 years or more.T-cells are capable of leaving and re-entering the circulation many times during their long life.T and B cells cannot be differentiated when viewing blood films.They are identified through the use of immunologic cell markers.
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| Where is the main site of action for monocytes? | View Page |
| T lymphocytes are larger and have more vacuoles than B lymphocytes. | View Page |
| The half-life of monocytes in the circulating blood is: | View Page |
| Monocytes Monocytes are phagocytes which remove injured and dead cells, cell fragments, microorganisms and insoluble particles from the blood and body tissues.Monocytes also secrete substances that affect the function of other cells, especially lymphocytes.They are produced in the bone marrow, and when mature are released into the peripheral blood. Although they do serve a phagocytic role in the blood, their main site of action is the body tissues.The half-life for monocytes in the peripheral blood is approximately 8 hours. Monocytes migrate into the tissues, often to sites of inflammation, where they serve their primary purpose.Here they transform into fixed or free macrophages, and continue their function as avid phagocytes.When activated, macrophages may enlarge and have enhanced metabolism.
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| Platelet Clumps Occasionally they occur in clumps, particularly if the film was made from capillary blood. | View Page |
| Platelet Kinetics Platelets are derived from the cytoplasm of megakaryocytes, giant cells in the bone marrow. At any given time, two thirds of the total platelets are in the circulation and one third are present in the spleen. In persons with enlarged spleens 80-90% of the platelets are in the spleen resulting in a decreased concentration of circulating platelets. In individuals who have had a splenectomy all of the platelets will be in the circulating blood. The life span of the platelet is 8-10 days. | View Page |
| Platelets Platelets are anucleate cells, measuring only 1-4 microns in diameter. They are the smallest of the formed elements found in normal peripheral blood. The arrows point to platelets. | View Page |
| All of the following statements describe a method by which platelets aid coagulation EXCEPT: | View Page |
| Platelet Function Platelets function both mechanically and biochemically in the process of hemostasis. When injury to a blood vessel occurs, platelets aggregate forming a plug which helps to stop the flow of blood. They release certain substances, among them serotonin and Platelet Factor 3. Serotonin causes the blood vessels in the area to constrict, thereby further stopping the flow of blood. Platelet Factor 3 catalyzes the coagulation reaction whereby a fibrin clot is formed, completing the seal. Platelets also maintain the integrity (leak-free) state of blood vessels.
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| Erythrocyte Shape In stained blood films, only the flattened surfaces of the RBC's are seen. Therefore, they appear circular with an area of central pallor corresponding to the indented area. The central pallor occupies about 1/3 of the diameter of the cell. | View Page |
| Function and Kinetics Erythrocytes are produced in the bone marrow and released into the peripheral blood where they may remain for approximately 120 days before senescence.Their main function is the transport of the respiratory gases (oxygen and carbon dioxide) between the lungs and body tissues.Each erythrocyte can be thought of as an "envelope" containing hemoglobin.Each hemoglobin molecule contains iron which has a high affinity for oxygen.As a result, when an erythrocyte passes through one of the capillaries of the lungs, it picks up oxygen.The oxygen is transported through the blood to the tissues where it is released.Carbon dioxide from the tissues then diffuses into the RBC where it undergoes chemical changes.About 70% of the altered carbon dioxide diffuses into the plasma, 25% binds to the hemoglobin molecule, and 5% goes into simple solution within the red cell.In each of these three ways carbon dioxide is transported from the body tissues back to the lungs, where it is released.
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| All of the following methods can be used to transport carbon dioxide to the lungs EXCEPT: | View Page |
| What is Blood Composed of? Blood is composed of an isotonic fluid (plasma) in which various cells (hemocytes) are suspended. There are three major groups of these cells. | View Page |
| Thrombocytes (Platelets) The third group of formed elements in normal peripheral blood is made up of thrombocytes (platelets). Although platelets don't look very impressive, their role in the process of hemostasis is critical. Platelets are the small granular bodies shown with the arrows in this Wright stained smear. | View Page |
| Overview All of these peripheral blood cells have different characteristics. In order to accurately identify each of them, a peripheral blood film must be made, preferably from capillary blood or blood anticoagulated with EDTA (Ethylenediaminotetracetic Acid). EDTA, in contrast to many other anticoagulants, preserves cellular morphology. The individual characteristics of each cell type are made visible by staining the blood films with the Wright stain, and observing them under the microscope. | View Page |
| Glossary of Terms A through M. Antibody - A modified type of serum globulin synthesized by lymphoid tissue in response to antigenic stimulus. By virtue of specific combining sites each antibody reacts with only one antigen. Anucleate - Having no nucleus. Azurophilic granules - The well-defined large reddish granules (lysosomes) which may be present in large lymphocytes. They are called "azurophilic granules" because they stain blue with the azure stains which were originally used. Basophilic granules - Specific granules present in the cytoplasm of basophils. These granules are large and stain purple-black due to their strong affinity for basic stain. B-cell - Bone marrow derived lymphocytes which produce humoral antibodies. Biconcave - Having two concave surfaces. Cellular Immunity - The capacity of a small proportion of lymphoid population to exhibit response to a specific antigen. Chromomere - The centrally located granular portion of the platelet. Clone - A population of cells descended from a single cell. Delayed Hypersensitivity - (part of cellular immunity) that develops slowly over a period of 24-72 hours after an antigenic stimulus. It consists of an accumulation of cells around small vessels and/or nerves. Example: Tuberculin skin test reaction. Digestive Enzyme - A substance that catalyzes or accelerates the process of digestion. Eosinophilic Granules - Specific granules present in the cytoplasm of eosinophils. These granules are large, refractile spheres which stain reddish-orange due to their strong affinity for acid stain. Erythrocyte (red blood cell, RBC) - One of the elements found in peripheral blood. Normally the mature form is a non-nucleated, circular, biconcave disk adapted to transport respiratory gases. Fixed Macrophage - A phagocyte that is non-motile. Free Macrophage - An ameboid phagocyte present at the site of inflammation. Graft Rejection - A transplanted tissue that is rejected by the body's antibodies. Graft vs. Host Reaction - A complication that occurs when an implanted piece of tissue, which contains antibodies, rejects the host's tissue. Granulocyte - A leukocyte which contains granules in its cytoplasm, i.e., neutrophilic, eosinophilic, or basophilic granules. Half-life - is the length of time it takes for half of the cells circulating at a given time to leave the blood for the tissues. Hemocyte - Any blood cell or formed element of the blood. Hemostasis - A mechanism of the vascular system to arrest an escape of blood. It involves an interaction between blood vessels, platelets, and coagulation. Heparin - A mucopolysaccharide acid which, when present in sufficient amounts, functions as an anticoagulant by inhibiting thrombin. Histamine - A powerful dilator of capillaries and a stimulator of gastric secretions. Humoral Immunity - Acquired immunity produced after response to an antigenic stimulus in which B cells produce circulating antibodies. Hyalomere - the clear, blue non-granular zone surrounding the chromomere of a platelet. Immune Response - The interaction of a cell and an antigen that results in a proliferation of the cell and a capacity to produce antibodies. Isotonic Fluid - A fluid whose elements have an equal osmotic pressure. Leukocyte (white blood cell, WBC) - One of the formed elements of the blood; involved primarily with the body's defense. Lysosome - A microscopic body within cell cytoplasm; contains various enzymes, mainly hydrolytic, which are released upon injury to the cell. Megakaryocyte - A giant cell of the bone marrow from which platelets are derived. Mononuclear - A cell having a single nucleus. | View Page |
| Glossary of Terms N through Z. N:C Ratio - Nuclear: cytoplasmic Ratio - The ratio of nuclear volume to cytoplasmic volume within any one cell.Neoplasm - Any new and abnormal growth, such as a tumor.Neutrophilic Granules - Specific granules present in the cytoplasm of neutrophils. These granules resemble pencil stippling and stain a lilac color due to their affinity for both basic and acid dyes.Phagocyte - Any cell that ingests microorganisms or other cells and foreign particles.Phagocytosis - The ingestion and destruction of microorganisms or other foreign particles.Plasma - The fluid portion of blood in which the various blood cells are suspended.PF3 (platelet Factor 3) - A lipoprotein component of the platelet membrane; functions as a surface catalyst during blood coagulation.Pseudopod - A temporary protrusion of the cytoplasm of a cell.Refractile - Capable of refracting or changing the direction of light.Senescence - The process or condition of growing old.Serotonin - A constituent of blood platelets and other cells and organs; induces constriction of the blood vessels.Specific Granules - Granules found in cells of the more mature stages of the granulocytic series. They have distinct staining reactions which differ with each type of granulocyte.T-cell - Thymus derived lymphocyte which mediates cellular immunity.Thrombocyte (Platelet) - A circular or oval disk found in the blood; concerned with hemostasis.Thymus - A ductless gland-like body situated in the anterior mediastinal cavity; reaches its maximum development during the early years of childhood.Vacuole - Any small space or cavity formed in the cytotoplasm of a cell. | View Page |
| Eosinophils Eosinophils are also known as eosinophilic granulocytes, or eos. Eosinophils are easy to recognize in the peripheral blood because of their large bright granules. The diameter of the eosinophil is 9-15 microns, and the nuclear to cytoplasmic (N:C) ratio is 1:3. Eosinophils are generally the largest granulocytes found in normal blood. | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| The most immature neutrophil found in normal peripheral blood is: | View Page |
| Band Neutrophil Band neutrophils are also referred to as stabs or simply as bands. The diameter of a band is approximately 9-16 microns, and its nuclear to cytoplasmic (N:C) ratio is 1:2. | View Page |
| Segmented Neutrophil Segmented Neutrophil may also be referred to as seg, polymorphonuclear leukocyte, poly and PMN. Segmented neutrophils are the most mature neutrophilic granulocytes present in circulating blood. Their diameter is approximately 9-15 microns, and their N:C ratio is 1:3. | View Page |
| Identify the nucleated blood cell: | View Page |
| Segmented and Band Nuclei The granulocytes found in normal peripheral blood are neutrophils, eosinophils and basophils.Most have segmented nuclei, and are therefore classified as being at the "segmented" stage of development. Some that are a little less mature have unsegmented nuclei. These are classified as "bands." Generally, we differentiate between the band and segmented forms of neutrophils, but since eosinophils and basophils are present in such low numbers, and since their nuclei are often obscured by cytoplasmic granules, we usually don't concern ourselves with designating the band forms.Since hematologists and textbooks use several different terms for these cells, synonyms for each term will be given and then may be used interchangeably throughout the course. | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Basophil Granules When examining a blood film you may find that some basophils have many dense granules while others appear washed out with only a few granules. This is because the granules are water soluble and tend to wash out during the rinse phase of the staining process. | View Page |
| Definition of a Segmented Cell continued. Since these recommendations have been adopted by many groups, including the College of American Pathologists and the Centers for Disease Control, we will be using them as our criteria for differentiating between bands and segs.This definition was first reported by the Committee for Clarification of the Nomenclature of Cells and Diseases of the Blood and Blood Forming Organs, in the American Journal of Clinical Pathology (18:443-450, 1948). | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| The Process of Phagocytosis Neutrophils have a relatively short life span.They are produced in the bone marrow, and when they reach the band or segmented stages are released into the peripheral blood.They remain there for approximately ten hours before randomly entering body tissues.Neutrophils in the blood stream can be divided into circulating granulocyte pool(CGP) and marginating granulocytic pool (MGP).The white blood cell count reflects the cells in the circulating pool.The cells in the marginating pool move quickly into the circulating pool when needed.During an infection the neutrophil concentration of the peripheral blood can increase almost immediately due to the shift of these cells from the marginating pool and release from the bone marrow storage pool, if needed.Neutrophils then migrate to areas of tissue damage or infection.Neutrophils do not reenter the blood stream from the tissues, thus end their life in the tissues either as a result of phagocytosis or senescence. | View Page |
| Life Span and function of Eosinophils Eosinophils have a circulating half-life of approximately 18 hours and a tissue life span of at least 6 days.They are capable of locomotion and phagocytosis and can enter inflammatory sites, but do so less readily than neutrophils.In tissues the primary location for eosinophils is in the epithelial barriers to the outside world such as, lungs, skin and GI tract.They are capable of returning to the circulating blood and bone marrow after they enter the tissues. | View Page |
| Eosinophils in Parasitic Infections and Allergic Reactions Eosinophils are active in parasitic infections and in allergic reactions such as asthma and hay fever, and may be present in great numbers in the peripheral blood during these conditions.Stress, shock, or burns may also cause an increase in this type of cell.Eosinophils modulate an allergic response by liberating substances which can neutralize mast cell and basophil products. | View Page |
| Basophils in the Blood Basophils circulate in the blood for a short time and make up only a small percentage (0.5%) of the cells in circulation.They do not migrate to the tissues under normal conditions but may be seen when inflammation resulting from hypersensitivity to protein, contact allergy or skin allograft rejection is present.Basophils are sometimes increased in patients with chronic myeloproliferative disorders.
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| Where do neutrophils serve their primary function? | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Apprearance of Cytoplasm Monos have abundant blue-gray cytoplasm containing many fine lilac granules. These give the cytoplasm a "ground glass" appearance. However, these granules may be difficult to see if the blood film is poorly stained. | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Identify the nucleated blood cell: | View Page |
| Discussion When the results on Mr. John Ready were called to the nurse, she was very surprised that the result of his CBC was normal. The nurse explained to the lab tech that Mr. John Ready had a known diagnosis of lower GI bleeding. His hemoglobin had been very low for the past 24 hours because of the internal bleeding, and she thought it was very surprising that his hemoglobin had normalized so quickly without having received a blood transfusion. Mr. Ready’s doctor decided the patient should be redrawn to ensure a correct result. The nurse further questioned if the phlebotomist could possibly have drawn the wrong patient because earlier that day Mr. Ready had been moved to room 831, and room 825 was presently occupied by a patient named Walter Redding. If Julie had checked the patient’s armband, she would have realized that the patient in 825 was the wrong patient.Relevant topics:Importance of patient ID, Patient identification continued, Specimen labeling,
Specimen labeling Continued, Blood bank specimens
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| Case Julie Smith was a newly certified phlebotomist and had been working at Northwood Hospital for several months. As she approached room 825, she looked on her collection list to verify this was the correct room for her first collection. Indeed it was, even though there was no patient name on the door. Her collection list told her the patient in room 825 was a 55 year old male named John Ready. After knocking several times, Julie entered the room to find a middle aged man who appeared to be sleeping. Julie approached the patient and said, “Good day Mr. Ready. My name is Julie and I am from the lab. I need to draw blood for some tests ordered by your doctor.” The man awoke and seemed irritated as Julie repeated herself. The patient responded and told Julie to do whatever she needed to do so he could go back to sleep Julie then proceeded to do the venipuncture. | View Page |
| What crucial step did Julie fail to perform? | View Page |
| Discussion A phlebotomist should never use an arm with restricted usage for the venipuncture. Even if no sign is posted, the patient may tell you not to use a particular arm for various reasons, i.e. previous mastectomy, history of phlebitis, active AV fistula, etc. Do not draw blood above an IV line. If blood is taken from a vein above an IV line it might be diluted by the IV fluid, which could cause incorrect test results. In this case, Bobby should choose a vein on the dorsum of Mrs. Grayson’s hand, below the IV. A butterfly needle would facilitate drawing blood from these small hand veins.Relevant topics:Alternate sites, Sites to avoid, Signs, Arms to avoid
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| Case Bobby Jones, a phlebotomist at Georgetown Hospital, entered the room of Mrs. Mary Grayson with a physician's order to draw some blood work. After properly greeting Mrs. Grayson, identifying himself and checking her armband, Bobby prepared for the venipuncture. He suddenly notice a sign posted above the bed that read: “Restricted left arm usage. Previous mastectomy - Do no use left arm for venipuncture.” Bobby set up his equipment to use her right arm and noticed an IV line in Mrs. Grayson’s right arm positioned in a vein slightly above her wrist on the dorsum (top) of her forearm. | View Page |
| Which site should Bobby choose for the venipuncture? | View Page |
| Case Marcie Moore was a phlebotomist at a community hospital in Atlanta. It was her week to collect the pediatric unit and she was on her way to the room of a newborn for which she had just received orders to draw a STAT BMP (chem-7) and bilirubin. After informing the mother of the baby about the test she needed to perform, Marcie set up to perform a heel stick on the baby. Marcie chose a site on the outer edge of the heel on the bottom of the baby’s foot ( the correct area for a heel stick) and made a small incision with a Tenderfoot lancet after cleaning the site well with alcohol.She immediately began collecting the blood in the correct tube for the BMP and bilirubin. Blood flow was not strong so Marcie squeezed the baby’s foot a little to help the blood come out faster – the newborn was screaming and Marcie could tell it was making the mother uncomfortable. She wanted to hurry and get done so the mother could hold the baby.After the chemistry tech ran the blood tests on the tube, she informed Marcie that the newborn had a panic potassium level which did not coincide with the previous blood work on the newborn. Also the chemistry instrument could not perform the bilirubin due to hemolysis. Marcie was asked to recollect the specimen. | View Page |
| Discussion Hemolysis can easily be caused by improper phlebotomy techniques. Hemolysis occurs when RBCs are broken up and hemoglobin is released into the plasma, causing it to become pink rather than its natural straw color. Hemolysis can occur by using too small a needle, pulling a syringe plunger too rapidly, expelling blood vigorously into a tube, or shaking a tube of blood too hard. Hemolysis can cause falsely increased potassium, magnesium, iron, and ammonia levels, and other aberrant lab results.In this case, Marcie did not properly wipe the site with gauze after cleaning it with alcohol, and alcohol contacting the blood could have caused RBCs to break up or hemolyze. Marcie also squeezed the baby’s foot too hard, causing hemolysis.Relevant topics:Site selection and preparation, Heelstick: Puncture, Hemolysis, Causes of hemolysis | View Page |
| What had Marcie done to hemolyze the specimen? | View Page |
| What could have caused the clotting? | View Page |
| Discussion Clotting of blood specimens may be caused by several factors. Clotting usually occurs due to improper phlebotomy technique,and clotted specimens will generally be rejected for those tests that require the blood to be mixed with an anticoagulant. When a clot forms in a tube containing anticoagulant, it usually indicates that the blood and anticoagulant aren’t in proper balance. That is why it is crucial to invert tubes with anticoagulant almost immediately after collection to ensure proper mixing of blood and anticoagulant. Relevant topics: Lavender top tubes, Light blue top tubes, Unsatisfactory specimens: Clots, Causes of clotting | View Page |
| Case John Wagner, a phlebotomist at General Hospital, went up to the 7th floor to draw routine blood work on a patient. As he approached the door of the patient’s room he noticed a red stop sign on the door with the words “Respiratory Isolation” written on it. | View Page |
| At this point, what should John know to do? | View Page |
| Case Julie Smith, a newly certified phlebotomist at Northlake Hospital, entered a patient’s room on the third floor for a routine blood draw. The patient was an elderly woman who had very small fragile veins. Julie therefore decided to use a safety butterfly needle attached to a Vacutainer tube in order to draw the blood. When Julie was finished with the venipuncture, she detached the butterfly needle from the Vacutainer, and approached the Biohazard needle disposal box. She noticed that the disposal box was full , but decided to try to fit the butterfly into the box anyway. Holding the butterfly by the tubing, she tried to push the butterfly into the box. The needle suddenly recoiled and stuck Julie’s finger. Julie left the patient’s room in a panic and headed back to the lab to report the needle stick injury. | View Page |
| What should Julie have done to prevent the needle stick? | View Page |
| Discussion Tubes are drawn in a specific order to avoid the possibility of erroneous test results caused by carryover of an additive from one tube to the next. If a blood culture is ordered, it should be drawn as the first tube. Additional tubes should follow this order of draw. Sodium citrate - coagulation tube (light-blue top) Serum tube - with or without clot activator or gel. This tube is either a red top tube or a gold top tube depending on manufacturer and tube additive. Sodium or lithium heparin with or without gel plasma separator (green top) Potassium EDTA (lavender or pink top) Sodium fluoride, and sodium or potassium oxalate (gray top) | View Page |
| Case Bobby Jones, a phlebotomist at Georgetown Hospital, was called to the pre-op area to perform a bleeding time. Bleeding times may be requested on selected preoperative patients to help assure that they will not bleed excessively during surgery. Bobby gathered the appropriate equipment, then placed the blood pressure cuff of the patient’s upper arm, and pumped it to 40 mm Hg. After finding the appropriate site (a few inches below the elbow on the inside of the forearm), Bobby cleaned the site with an alcohol pad and immediately made the incision with a Surgicutt parallel to the bend of the elbow. Bobby then wiped away the first drop of blood with an alcohol pad, and blotted the incision every 30 seconds thereafter. Fifteen minutes later the patient was still bleeding. | View Page |
| What did Bobby do that could have falsely prolonged the bleeding time? | View Page |
| Discussion The blood pressure cuff was correctly inflated to 40 mmHg. The site for the incision is indeed the inside of the forearm a few inches below the bend of the elbow, and the cut was correctly made parallel to the bend of the elbow. However, the phlebotomist did not allow the alcohol to dry, and then made the additional mistake of wiping the incision with alcohol. Alcohol will retard blood coagulation, resulting in a falsely elevated bleeding time. It is also important to ask the patient about medications taken within the past week. Certain medications, particularly aspirin, will result in an elevated bleeding time.Relevant topics:Bleeding time: introduction 1, Bleeding time: introduction 2, Bleeding time: performance, Bleeding time, Apply blood pressure cuff, Bleeding time: prepare the site | View Page |
| Case A phlebotomist at an outpatient drawing station prepares to collect blood from a patient who is scheduled for surgery the next day. The patient tells the phlebotomist that she is afraid of needles. The phlebotomist assures the patient that everything will be fine. He seats the patient in a phlebotomy chair. He talks the patient through the beginning of the venipuncture and she seemed to be doing fine. As the second of four tubes is being drawn, the patient suddenly blurts out that she fells very dizzy and is going to faint. | View Page |
| What should the phlebotomist do now? | View Page |
| Discussion Insufficient blood volume may cause erroneous test results, and specimen rejection. When blood flow stops, it can mean several things:The bevel of the needle may be pressed against the wall of the blood vessel. If this is the case, moving the needle slightly may cause blood to begin flowing again.The vein may have collapsed due to the vacuum of the tube. If moving the needle slightly does not re-establish blood flow, you will have to recollect the patient.The needle may have gone all the way through the vein. Pulling the needle back slightly may cause blood to resume flowing.
The tube you are using may have insufficient vacuum. Try another tube. Never vigorously probe the patient’s arm with a needle. At the first sign of discomfort the needle should be withdrawn. The patient may then be redrawn be yourself or another phlebotomist.Relevant topics: Insufficient volume, Partial collection tubes, What if no blood flows | View Page |
| Case A phlebotomist was collecting STAT blood work on a patient when blood flow unexpectedly stopped. The light blue top tube being drawn at the time was only about one third full – less than the minimum volume required for this particular tube. A red top tube had already been drawn for a cross match, and a PT was the only other test ordered. | View Page |
| What could the phlebotomist do at this point to renew blood flow? | View Page |
| Discussion During a finger stick procedure it is important that the lancet be positioned on the finger so that the incision is perpendicular to the fingerprint. This allows a larger amount of blood to flow. It is also important to wipe away the first drop of blood that emerges form the incision with clean gauze, since it may contain tissue fluids that can cause incorrect test results. The first drop of blood may also contain traces of alcohol remaining from the cleaning step. Alcohol may break up or hemolyze blood cells, causing incorrect results.Relevant topics:Finger-stick collections, Finger-stick: site preparation, Finger-stick: puncture, Wipe away the first drop, Finger-stick specimen collection | View Page |
| Case A phlebotomist at Memorial Hills Hospital entered the room of a 6 year old patient. The only test ordered was a CBC, so the phlebotomist decided to do a finger stick. After gathering proper supplies for the finger stick, the phlebotomist began the procedure by putting on gloves and wiping the tip and side of the patient’s ring finger with alcohol. He positioned the safety lancet between the ball and the side of the finger and made a small incision. The child cried as the blood was collected.
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| Case A phlebotomist from the laboratory at Midtown Memorial Hospital was working evening shift. Her shift ended at 11 PM and it was 10:30 PM. She suddenly got orders for a STAT blood culture on the second floor. The order specified blood culture times two, 30 minutes apart. The phlebotomist went to the patient’s room and decided to collect both blood cultures at the same time form the same site so she would be able to leave on time without having to come back in thirty minutes to collect the second set. She also wanted to “save” the patient from an extra stick. While the phlebotomist was preparing for the collection, she realized she didn’t have any Betadine on her tray, and decided she would just clean the site twice with alcohol. She finished the blood culture collections and was able to leave by 11 PM. | View Page |
| Discussion This phlebotomist violated hospital procedures in several ways that could adversely impact patient care:
Cleaning the site only with alcohol, not iodine, could result in a false-positive contaminated blood culture. This might result in the patient receiving unnecessary intravenous antibiotics, and could prolong the patients hospital stay unnecessarily.
Drawing both cultures at the same time lessens the chance of recovering a bloodstream organism.Drawing both cultures from the same site might result in both of them being contaminated, making it very difficult for the physician to distinguish contamination from a “real” bloodstream infection.Relevant topics:Blood cultures: introduction,
Avoid skin contamination, Blood culture site preparation 1, Blood culture site preparation 2 | View Page |
| What did the phlebotomist do wrong? | View Page |
| Basic metabolic panel (BMP) Consists of an electrolyte panel, plus:
Blood urea nitrogen (BUN), which a measure of renal function.
Creatinine (Creat), which also measures renal function
Glucose, the most important blood sugar, and
Calcium.
Run on serum or plasma
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| Hemogram (CBC) Also known as Complete Blood Count (CBC) and is run on whole blood.Blood is tested for quantity and quality of different blood cell types, including:
White Blood Cells (WBC Count)
Red Blood Cells (RBC Count)
Platelets (Platelet Count)
Blood is also tested for hemoglobin & hematocrit (H&H).
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| Electrolytes panel (Lytes) Blood is tested for the most important electrolytes (salts):
Sodium (Na)
Potassium (K)
Chloride (Cl)
Carbon dioxide (CO2)Can be run on serum or plasma.
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| Obstetric panel CBC
Hepatitis B surface antigen
Antibody, rubellaSyphilis test (RPR)
Antibody screen
Blood type, Rh and ABO
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| Blood collection tubes: sizes Adult tubes generally hold from 3 to 10 ml of blood.
Pediatric tubes usually hold from 2 to 4 ml.Tubes for fingersticks or heelsticks generally hold one half ml or less.
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| Lavender top tubes Contain anticoagulant Ethylendiaminetetraactic acid (EDTA) to prevent clotting.
Are used mostly for hematology studies.
Must be completely filled to assure a correct anticoagulant to blood ratio.
Must be inverted after filling to assure proper mixture of anticoagulant with blood.
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| Yellow top tubes Contain either acid citrate dextrose (ACD), which maintains RBC viability and may be used for HLA phenotyping, DNA, paternity testing, or lymphocyte surface markers, or:
Sodium polyanetholesulfonate (SPS) which is sometimes used to collect blood culture specimens.
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| Butterfly needles with built-in safety features continued Two examples of butterfly needles with built-in safety devices are shown.The Punctur-Guard™ (Bioplexus), shown above, uses an internal blunt needle which is activated after blood is drawn. The activated device showing the blunt internal needle is shown in the inset on the upper right.
The Angel Wing ™ (Monoject), is activated by sliding a safety shield over the needle after venipuncture.
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| Syringes Syringes consists of:A barrel, which holds the blood.
A plunger that allows suction to be appliedA tip to which the needle is connected.Syringes have ml (cc) markings to show how much blood has been collected.
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| Blood collection tubes: common types Lavender top
Light blue top
Green top
Red top
Speckled top
Gray top
Yellow top
Royal blue top | View Page |
| Multiple draw needles Multiple draw needles are used with vacuum collection tubes.They allow the collection of blood into multiple vacuum collection tubes during a single venipuncture.
They have a retractable sheath over the portion of the needle that penetrates the blood tube.
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| Blood collection tubes: types Rubber stoppers of blood collection tubes are color coded.
Each type of stopper indicates a different chemical additive (usually an anticoagulant to prevent clotting), or a different tube type.
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| Multiple draw needles with built-in safety features. You will be required to use multiple draw needles with built-in Safety features.
One example is the Puncture-Guard™ (BioPlexus) needle, which uses an internal blunt needle (detail above) that is activated with forward pressure on the final blood tube prior to withdrawal of the needle from the vein.
Refer to your institution’s and the manufacturer’s procedure manuals before using these devices.
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| Blood collection tubes: introduction A blood collection tube generally consists of a glass or plastic tube with a rubber stopper. It has a vacuum so that blood will flow into the tube.
Blood collection tubes may contain anticoagulants and/or other chemical additives.
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| Syringes with built-in safety devices Syringes are used for injections, as well as to collect blood.
There a various syringes with built-in safety features.One example is the Monoject™ (Sherwood Services AG), Safety Syringe, shown here. | View Page |
| Gloves Gloves must be worn for all procedures requiring vascular access.
Non-powdered latex gloves are most commonly used;
Alternatives available for health-care workers allergic to latex include:
Latex gloves sandwiched between 2 vinyl gloves.
Latex-free glove liners.Do not use latex gloves or tourniquets when collecting blood from patients with latex allergy. | View Page |
| Blood culture bottles Are used to collect sterile blood samples from patients who may be septic (have bacteria or other organisms growing in their bloodstream).
Different blood culture bottles are used for aerobic, anaerobic, and pediatric collections. | View Page |
| Needle components The tip of the needle consists of a:
A very sharp tip for puncture.A bevel which allows for blood flow.
A barrel which allows for blood flow.
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| Blood transfer device A blood transfer device allows the transfer of blood from a syringe into a blood collection tube or a blood culture bottle.
The BD™ blood transfer device is shown here.
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| Butterflies with built-in safety features You will be using butterfly needles with built in safety features.
Butterfly needles are the number-one cause of needlestick injuries, so proper use of their safety devices is critical.
Their use is described in greater detail in the section on butterfly needle blood collection.
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| Plastic holders used with the evacuated tube system A plastic holder must be used with the evacuated tube system.
The needle screws into the holder to allow blood collection.
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| Introduction to phlebotomy equipment The following section will familiarize you with the supplies & equipment you will need to collect a blood specimen.
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| Phlebotomy trays A Phlebotomy tray is used to carry blood drawing equipment to the bedside.Trays should be sanitized daily, & kept well-stocked and organized.
Phlebotomy trays may be sanitized using 10% bleach solution, or other appropriate disinfectant.
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| Hemogard ™ blood collection tubes Blood collection tubes with Hemogard ™ (BD) closure protect you from blood which might splatter when the tube is opened.
The rubber stopper is recessed inside the plastic shield, preventing exposure to blood present on the stopper.
You will probably be using Hemogard or other tubes having protective devices.
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| Blood collection tubes: inversion All tubes (except red top tubes which contain no additives) must be gently inverted 5 to 8 times immediately after filling, to ensure proper mixing of blood and anticoagulant, or other additives.
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| Blood collection tubes: expiration dates All blood collection tubes have expiration dates.
Expiration dates should be closely monitored and tube stock must be rotated.
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| Light blue top tubes These tubes contain the anticoagulant sodium citrate.
They are used mostly for coagulation (clotting) studies.
They must be completely filled to assure proper ratio of anticoagulant to blood.They must be inverted immediately after filling to prevent clotting.
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| Green top tubes Contain either sodium or lithium heparin.Used for tests requiring whole blood or plasma such as ammonia or whole blood potassium.
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| Red top tubes Contain no additives.
Used for blood bank tests such as blood typing, type and screen, and crossmatches.
Also used for other tests including toxicology, and serology.
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| Speckle top tubes Also known as serum separator tubes, tiger top tubes or red gray tubes.
Contain a serum-cell separator gel which separates serum from clotted blood cells during and after centrifugation.
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| Remove needle Removing the needle:Gently release the tourniquet before the last tube of blood is filled.Remove the last tube from the needle.Withdraw the needle in a single quick movement. | View Page |
| Finger stick - Specimen collection Gently massage the finger from base to tip to collect blood into the appropriate tube.Avoid hemolysis:Do not squeeze the finger too tightly during blood collection.
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| Applying the tourniquet Tie the tourniquet just above the elbow.The tourniquet should be tight enough to stop venous blood flow in the superficial arm veins. | View Page |
| Push tube onto holder Gently push the tube onto the needle holder so that the catheter inside the needle holder penetrates the tube.Blood flow should be visible at this point. | View Page |
| Blood won't flow If you do not see blood flow, the tip of the needle:May not yet be within the vein.May have already passed through the vein.May have missed the vein entirely.May be pushed up against the inside wall of the vein. | View Page |
| Adjust needle Advance or withdraw the needle slightly, if necessary, to establish the flow of blood. | View Page |
| Venipuncture Standard precautions Treat all blood & body fluids as if they were infectious.Always wear gloves during vascular access procedures. | View Page |
| Butterfly needle - Butterfly needle collections Butterfly needles (also known as a winged infusion set), are available in smaller gauges, and are used to draw venous blood from children, and adults with difficult veins.
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| Finger stick - Specimen collection continued Collect blood into an appropriate tube.Label specimens appropriately.Make sure bleeding has stopped. Apply an adhesive bandage if necessary.Discard sharps appropriately. | View Page |
| Heelstick - Neonatal Blood collection Microlances (such as the Tenderfoot™ (ITC) or the QuikHeel™ (BD), shown here, are used to puncture the heel & collect capillary blood.These devices control the depth of incision, since going too deep into an infant’s heel could injure the heel bone, and cause osteomyelitis (bone infection). | View Page |
| Butterfly needle - Butterfly needles with built-in safety features You will be using butterfly needles with built-in safety device. The safety device must be activated upon completion of the blood collection.You will be using butterfly needles with built-in safety device. The safety device must be activated upon completion of the blood collection.The Angel Wing™ (Monoject) safety butterfly is shown here.
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| Finger stick - Finger stick collections A finger-stick collection is performed by piercing the fingertip with a safety Lancet, which controls the depth of incision, and collecting capillary blood. The BD Microtainer™ Brand Safety Flow Lancet is shown here.Finger-sticks should not be performed on children under one year of age.
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| Finger stick - puncture Select a safety lancet appropriate for the size of the patient’s finger.You may warm the finger prior to puncture to increase blood flow.Make the puncture perpendicular, rather than parallel, to the finger print. | View Page |
| Finger stick - Wipe away the first drop Wipe away the first drop of blood using gauze to remove tissue fluid contamination. | View Page |
| Syringe - Syringe blood collections Syringes may be used to collect blood from patients having small or delicate veins that might be collapsed by the vacuum of the evacuated tube system.Syringes may also be used to collect blood culture specimens. | View Page |
| Syringe - Syringe blood collections continued Syringes may be used in two ways:Syringes may be used in two ways:A syringe may be attached to a butterfly or winged infusion set.
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| Syringe - Transferring blood to collection tubes After collecting the blood specimen into a syringe, properly activate the appropriate safety device, and dispose of the needle in a sharps container.Attach the syringe to a blood transfer device by twisting the needle tip into the hub of the device.Push a vacuum blood collection tube into the holder of the transfer device, and let the tube fill to the appropriate level.
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| Syringe - Transferring blood to collection tubes contd It is important to transfer the blood to appropriate tubes immediately because a syringe contains no anticoagulant, and the transfer must be complete before blood starts to clot.Do not push the plunger while transferring blood into a collection tube.
This may cause hemolysis, ruining the specimen. | View Page |
| Heelstick - Pediatric collection procedures: Introduction Veins of small children and infants are too small for venipuncture;Safety Lancets are used to puncture the skin and collect capillary blood.Butterfly needles may be used to collect venous blood in older children.
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| Heelstick - Site selection and preparation Firmly grasp the infants foot. Do not use a tourniquet. The heel may be warmed with a cloth to help increase blood flow. Wipe the collection site with an alcohol prep pad, and allow the alcohol to dry. Wipe the site with sterile cotton or gauze, to be sure all the alcohol has been removed. | View Page |
| Heelstick - Puncture Puncture the left or right side (outskirt) of the heel, not the bottom of the foot.Wipe away the first drop of blood since it may contain excess tissue fluid or alcohol which could alter test results. | View Page |
| Heelstick - specimen collection Collect the blood into the appropriate tube.Do not: Squeeze the infant’s foot too tightly and wipe with alcohol during the collection.These actions could result in hemolysis (breakdown of the red blood cells), invalidating the test results. | View Page |
| Introduction continued Prolonged bleeding time may indicate:Reduced numbers of platelets.Poorly functioning platelets, or:Medications such as aspirin, which inhibit platelet function, have been recently taken.
Abnormal blood vessels may also prolong bleeding time.
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| Wick the blood After 30 seconds, wick the flow of blood using a Whatman #1 filter paper disk.Wick the blood every 30 seconds until bleeding stops.
Bring the filter paper close to the incision, but do not touch the incision with the filter paper.
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| Apply blood pressure cuff Apply a blood pressure cuff on the patient’s upper arm, and inflate it to 40mm Hg.Blood pressure cuff must be maintained at 40 mm Hg for the duration of the test. | View Page |
| Additional tips Contaminated blood cultures may have very serious consequences in terms of patient care.Always draw blood cultures prior to drawing other blood tubes to minimize the risk of contamination.
Do not draw blood cultures from a central line, unless cultures are being drawn to determine whether or not the line is contaminated. | View Page |
| Introduction Blood is normally sterile. Any bacterial growth in the bloodstream is abnormal, and is an important cause of fever.Blood culture means the incubation
of blood in appropriate media to allow growth and identification of bacteria or other organisms that may be present in a patient’s bloodstream.
Blood cultures are performed on febrile patients to identify and treat bloodborne organisms with the most appropriate antibiotic. | View Page |
| Collection methods Blood for culture can be collected in several ways:Standard needle attached to a syringe.Butterfly needle attached to a syringe.Blood culture bottle attached directly to tube holder (not generally recommended).Follow you own facilities’ procedure for blood culture collection. | View Page |
| Avoid skin contamination Normal skin is not sterile – it contains numerous bacteria.These normal skin bacteria can contaminate a blood culture, causing a false-positive blood culture result.Thorough decontamination of the skin puncture site is therefore essential prior to obtaining the blood culture specimen. | View Page |
| Equipment These items are needed to obtain a blood culture specimen :Gloves (sterile if available)Alcohol pads and sterile gauze padsTourniquet and iodine swabsBlood culture bottlesSyringes, needles, and/or evacuated tube system. | View Page |
| Clean the bottle tops Clean blood culture bottles while the iodine on the venipuncture site is drying. Wipe the tops of the blood culture bottles, first with a new iodine swab, then with a clean alcohol pad. | View Page |
| Volume is important Collect the volume of blood recommended by the manufacturer of the blood culture bottles
It is important to collect this full volume if possible. Short draws will make the blood culture less likely to grow. | View Page |
| Activate needle safety device After collecting the blood, activate the needle safety device according to manufacturer’s instructions, and place it in a sharps disposal container.
If blood was collected into a syringe, insert the syringe tip into the hub of a blood transfer device, and rotate the syringe clockwise to secure it to the device.
Push the blood culture bottle into the holder of the transfer device, and draw the appropriate volume of blood into the blood culture bottles. | View Page |
| Additional tips continued Good sterilization is the key to avoiding contaminates:Let the iodine dry before drawing the blood.Be sure to wipe your gloved finger with iodine if palpation is necessary after cleaning.
Always remove iodine from blood culture bottle with alcohol to prevent iodine from “sterilizing” the culture, and causing a false negative result. | View Page |
| Concept of Hollister and similar systems The card has adhesive labels:for blood products,for the blood specimen, anda detachable armband stub,all with identical transfusion numbers. | View Page |
| Hollister system: specimen collection and labeling Positively identify the patient in the usual manner.Collect a venous blood specimen in a red top tube.Complete the specimen label and the detachable armband stub before removing them from the card.Initial, date, and time the stamped specimen label (shown on upper right), and attach it securely to the blood specimen. | View Page |
| Hollister and similar systems The Ident-A-Blood (™Hollister) or other similar systems (shown here) help assure that each patient gets the correct blood products.
These systems consists of a card with matching numbered labels, and an armband. | View Page |
| Arms to avoid In general, do not collect blood from:Arms on the same side as a previous mastectomy.Arms with phlebitis or infection.Arms with a vascular shunt.
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| Hematosis A hematoma is a blood clot which forms within the body. It is caused by leakage of blood into the tissues from an injured vein . It will resolve spontaneously.Hematomas are caused by excessive needle trauma to a vein, for example, by a needle which passed entirely through a vein and came out the other side.Apply compression to help stabilize a hematoma.
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| Blood should not be drawn from arms with IVs Blood drawn from veins with intravenous lines (IVs) may be diluted by the IV fluids. Arms containing IVs should therefore not be used to draw blood specimens.
If an arm with an IV line in place must be used for venipuncture, be sure to choose a site below the location of the IV, so that the specimen will not be diluted with IV fluids. | View Page |
| Patients refusing blood work If someone hesitates to let you collect a blood specimen, explain to them that their blood test results are important to their care.However, patients have a right to refuse blood tests. If the patient still refuses, report this to the nurse or physician, and document patient refusal according to your hospital’s policies and procedures.
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| What if no blood flows when the needle is in place? The needle may not be in a vein. Try slightly manipulating the needle. If no blood flows, withdraw the needle and repeat the venipuncture. Never probe the patient’s arm with the needle. The bevel of the needle may be compressed against the inside of the vein wall. Slightly manipulating the needle should result in blood flow.
The needle may have passed entirely through the vein. Pull it back slightly, and blood should flow. | View Page |
| Insufficient volume Insufficient blood volume (short draws) within a collection tube containing anticoagulant will result in an incorrect ratio of blood to anticoagulant, and yield incorrect test results.Short draws can be caused by: A vein collapsing during phlebotomy.The needle coming out of the vein before the collection tube is full.Loss of collection tube vacuum before the tube is full. (Always keep extra tubes on hand.) | View Page |
| Causes of hemolysis Hemolysis can be caused by: Shaking the tube too hard.Using a needle that is too small.Pulling back too hard on a syringe plunger.Pushing on a syringe plunger too hard when expelling blood into a collection device.
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| Causes The most common causes of unsatisfactory specimens are:
HemolysisClottingInsufficient Blood (“short draws”)Labeling Errors Each of these will be discussed in turn. | View Page |
| Clots Blood clots when the coagulation factor proteins within the plasma are activated.Blood starts to clot almost immediately after it is drawn unless it is exposed to an anticoagulant.Clots within the blood specimen, even if not visible to the naked eye, will yield inaccurate results. | View Page |
| Causes of clotting Clotting can be caused by: Inadequate mixing of blood and anticoagulant within the collection tube.Delay in expelling blood within a syringe (which contains no anticoagulant), into a collection tube with anticoagulant. | View Page |
| Partial collection tubes Filling a light blue-topped tube to its recommended volume is especially critical; if it is filled incompletely, coagulation results will be incorrectly reported as abnormal.If a short draw is anticipated, a “partial collection” tube which contains less anticoagulant and requires less blood may be used.The light blue topped collection tube shown on the left requires reduced blood volume, and is filled only to the line.
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| What is a phlebotomist’s role in a health care facility? The phlebotomist collects blood & other specimens which ultimately provide doctors and nurses with laboratory test information critical to patient care.He or she therefore plays a vital role in any health care system.
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| What is a phlebotomist’s role in health care facility? [continued] Phlebotomists work in a variety of settings including:
Hospitals
Physician Offices
Nursing Homes
Home Health Care
Clinics, and
Military facilities.
A well trained phlebotomist will therefore have a variety of job opportunities available.Other medical professionals, including nurses, respiratory therapists, and medical assistants may also be trained to collect blood specimens.
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| What is phlebotomy? Phlebotomy, also known as venipuncture, means collecting blood from veins.Phlebotomists, by definition, collect venous blood, but perform a variety of other important medical tasks as well. | View Page |
| What is a phlebotomist? A phlebotomist is a medical professional who:Collects blood and other specimens.Prepares specimens for testing.
Interacts with patients & health care professionals.
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| What is a phlebotomist? [continued] An experienced phlebotomist should be knowledgeable in the collection of:
- Venous blood specimens
- Capillary blood specimens
- Blood culture specimens
- Urine specimens
- Throat cultures, and
- Medico legal specimens requiring chain of custody.
He or she should also know how to:
- Process specimens
- Perform bleeding times, and
- Collection specimens from IV lines and central venous lines, under appropriate supervision.
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| Work-flow cycle: patient ID to specimen processing Phlebotomist positively identifies patient.
Phlebotomist draws and labels blood specimen.
Specimen is transported to laboratory.
Specimen is accessioned and processed in lab.
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| Standard precautions continued Potentially infectious body fluids include:
Blood, Semen, Vaginal Secretion, Peritoneal, pericardial and pleural fluids, and Saliva
Sweat and tears are not generally considered infectious.
It is important to remember that bloodborne pathogens are not transmitted by casual contact, like a handshake.
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| Personal protective equipment An impermeable lab coat should be worn to protect clothing from blood & other body fluids.
Gloves must be worn while drawing blood and during all other patient contact.
Appropriate face masks must be worn during contact with patients in certain types of isolation. A sign posted on the patients door will indicate special protective equipment that may be required prior to entering a patient room. | View Page |
| Needlestick safety and prevention act continued The law requires that each institution gets input from employees actually involved in blood collection.
So the actual safety devices you are required to use will vary depending on where you work.
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| Cardiovascular system : structure & function The cardiovascular system consists of the Heart, and Blood Vessels.
Its main function is circulate oxygenated blood from the lungs to various organs, and return blood depleted of oxygen to the lungs, where it is reoxygenated.
Illustration this screen from LifeArt Collection 2000, with permission. © Lippincott Williams & Wilkins.
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| Circulation: venous portion Deoxygenated (venous) blood flows from tiny capillary blood vessels within the tissues via progressively larger veins to the right side of the heart.Blood is routinely drawn from veins, but may also be drawn from arteries, or capillaries.
Illustration this screen from LifeArt Collection 2000, with permission. © Lippincott Williams & Wilkins.
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| Circulation: arterial portion Blood is then pumped from the right side of the heart to the lungs, where it takes up oxygen.
Oxygenated blood is then pumped through the left side of the heart via arteries to tiny blood vessels called capillaries.Illustration this screen from LifeArt Collection 2000, with permission.
© Lippincott Williams & Wilkins.
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| Circulation: capillary portion In the capillaries, oxygen and nutrients diffuse from the blood cells into the tissues.
The deoxygenated blood then returns to the veins, completing the circulatory pathway.
Illustration this screen from LifeArt Collection 2000, with permission. © Lippincott Williams & Wilkins.
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| White blood cells Leukocytes, or white blood cells, help the body fight infections.
Leukocytes are shown in the photomicrograph of the stained blood smear to the right.
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| Blood clots When a blood sample is left standing without anticoagulant, it forms a coagulum or blood clot.
The clot contains coagulation proteins, platelets, and entrapped red and white blood cells.
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| Plasma Plasma and formed elements stay mixed in circulating blood.
When centrifuged (or spun down), blood is separated into plasma, and formed elements including red blood cells. The plasma separator tube shown here has a barrier to maintain separation of plasma and cellular elements during centrifugation and storage.
The red cell layer also includes a relatively small amount of platelets and white blood cells, not visible in the photo on the right.
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| Plasma components Plasma is the liquid portion of the blood. It contains many substances including:Water
Electrolytes
Sugars
Proteins
Lipids
Drugs & Toxins
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| Plasma water Water (HĢ0) makes up the majority of the blood plasma. | View Page |
| Plasma water continued Water is the largest component of plasma, and makes up about 53% of whole blood.
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| Plasma sugars Sugars are also dissolved in the plasma. By far the most important is glucose.
Blood glucose is increased in diabetes mellitus, and decreased in hypoglycemia.
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| Plasma proteins Numerous types of proteins are dispersed in the plasma. These include:
Coagulation proteins (blood clotting factors), which, if activated, will form a blood clot , and
Serum proteins, which are left dispersed in liquid after the clot is formed. Serum proteins include:
Albumin, a marker of nutrition, and
Globulins, or antibodies. | View Page |
| Whole blood: components Circulating whole blood is a mixture of:
Plasma (which contains fluid, proteins, and lipids), and
Formed elements, consisting of red cells, white cells, and platelets.
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| Serum Serum is the fluid that is left over the coagulum after the specimen is centrifuged (spun down).
Serum contains all the same substances as plasma, except for the coagulation proteins, which are left behind in the blood clot.
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| Platelets Platelets are small cell fragments present in large numbers in blood.They work together with the blood coagulation proteins to form a blood clot. | View Page |
| Whole blood formed elements Formed elements are the cells suspended in the blood. They include:
Red blood cellsWhite blood cells
Platelets
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| Red blood cells Red blood cells contain hemoglobin, which carries oxygen from the lungs to the tissues of the body. Hemoglobin gives blood its red color.
Red blood cells are shown in the photomicrograph of a stained blood smear to the right.
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| Plasma lipids Lipids are fats dispersed in plasma. They include:
Triglycerides
Cholesterol
Lipoproteins
The amount and ratios of various lipids in the blood will determine a person’s risk of getting coronary artery disease.
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| Anatomy & physiology: essential to phlebotomy Since phlebotomy involves puncture of the skin (integumentary system) and veins,
(A component of the cardiovascular system), a basic knowledge of the anatomy and physiology of these systems is essential.
Knowledge of blood and its components is also important.
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| Collection tubes Blood may be collected into either:Red top (clot) tubes.Speckle top tubes (serum separator tube).Gray top tubes specifically designed to preserve glucose levels.
Gray top tubes contain additives such as sodium fluoride or potassium oxalate, which prevent metabolism of glucose by blood cells.
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| Administration of glucose Collect venous blood for a fasting glucose level.Give the patient a standard dose of glucose, usually in the form of a beverage such as Glucola™ (Allegiance). Always follow your own procedure manual.
In general:Give a 50 gram glucose dose to screen pregnant women at 28 weeks for gestational diabetes.Give a 75 gram glucose dose to nonpregnant adults.Give a 100 gram glucose dose to confirm the diagnosis of gestational diabetes. | View Page |
| One hour screening test for gestational diabetes About 2-3% of women will develop gestational diabetes.Since women with gestational diabetes have a higher risk of losing their baby or having a baby with malformations, diagnosis and treatment of gestational diabetes is important.Pregnant women are screened for gestational diabetes at 28 weeks using a modified glucose tolerance test.Patients are given a 50 gm dose of Glucola, and blood is collected for glucose testing one hour later.If the glucose level is greater than 140 mg/dl, a 3 hour glucose tolerance test is required to confirm the diagnosis of gestational diabetes. | View Page |
| Introduction Glucose tolerance test is used to help diagnose diabetes mellitus, or gestational diabetes (diabetes occurring during pregnancy).Patients are given a standard oral dose of glucose, after which their blood is collected at standard time intervals.
Blood samples are then checked for glucose levels.
Abnormal glucose levels may indicate diabetes mellitus, or gestational diabetes mellitus. | View Page |
| Specimen collection To screen for gestational diabetes, collect blood after one hour.For a standard glucose tolerance test collect blood and urine at 30 minute intervals, for two hours.To confirm gestational diabetes, collect blood every hour for 3 hours.
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| Introduction Physicians need to know the blood concentration of certain drugs in order to select the best dose for their patients.As a phlebotomist, you might be asked to draw peak (highest), and trough (lowest) levels of various therapeutic drugs. | View Page |
| Collection kits Sealed collection kits are opened in the presence of the donor individual.The kit contains detailed directions and materials for urine and blood collection.
Use only the materials supplied in the kit.You may have to appear in court later to testify as to how you collected the specimens, and to verify their origin, so follow directions carefully.
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| Blood Collect the blood specimen next, if required.Be sure to use the iodine swab provided in the collection kit to disinfect the venipuncture site.Do not use an alcohol swab, as this might lead to suspicion of a falsely elevated blood alcohol result. | View Page |
| Blood bank specimens Labeling of blood bank specimens is even more critical than labeling of other specimen types.If a patient gets the wrong unit of blood, a serious or even fatal transfusion reaction may occur. | View Page |
| The condition most likely associated with the peripheral blood picture shown in the photograph is: | View Page |
| The condition most likely associated with the peripheral blood picture in the photograph is: | View Page |
| What are the erythrocyte inclusions that are indicated by the arrows on this blood smear? | View Page |
| The nucleated red blood cell and myelocyte photographed here were found on scanning of a peripheral blood smear. In context they are suggestive of metastatic carcinoma to the bone marrow. | View Page |
| The erythrocyte at the tip of the arrow is an echinocycte (burr cell). | View Page |
| The peripheral blood picture shown in the photograph is most consistent with an artifact of smear preparation. | View Page |
| The peripheral blood picture is consistent with each of the following conditions except: | View Page |
| G6PD deficiency A ten-year-old boy came to a physician's attention because of recent jaundice and icteric sclerae. The immediate laboratory work revealed: Hct 24%(normal 36%-47%), MCV 79.5 fl (normal 78-95fl),RDW 13%(normal 11.5-15.0%). His blood smear findings are reflected in these photomicrographs. Note particularly the spherocytes in the upper picture. Some resemble a half-blister with the other half of the cell containing solidly-staining hemoglobin. These are called eccentrocytes. When present, they should trigger a search for red cell hereditary G-6PD deficiency and the oxidant that triggered hemolysis. These morphological findings are only clues; specific testing for G-6PD deficiency should be performed. The blue arrows in the upper photomicrograph are directed toward solid-staining spherocytes in which the cell membrane is beaded by inclusions wrapped within the cell membrane, suggesting the remains of denatured hemoglobin. Included on the smear is a target cell, several acanthocytes, a smudge cell, and a few schistocytes. The lower photomicrograph is supravital staining of affected red blood cells, verifying the presence of Heinz bodies. This disorder was first recognized during the Korean war in 10% of black American soldiers given the antimalarial drug primiquine. | View Page |
| Reticulocyte identification Reticulocytes are red blood cells prematurely released from the bone marrow. On a Wright-Giemsa stained blood smear, they appear as polychromatic macrocytes. Their presence in the peripheral blood may suggest hemolysis or bleeding. Their presence is expressed as a percentage of the red cell count: newly born= 3-7%; up to one week of age=1-3%; >one week =0.3-1.8%. Automated or manual methods may be used to enumerate reticulocytes. In clinical context, retics must be separated from debris, precipated stain, Pappenheimer bodies, Howell-Jolly bodies, and Heinz bodies. | View Page |
| The RBC inclusions shown in the photograph represent which of the following? | View Page |
| Intracellular RBC Inclusions-G6PD (continued) G6PD deficiency occurs in the same geographic distribution as malaria. It has been theorized that enzyme deficient cells are more resistant to malarial parasites than normal cells.When hemolysis is triggered, the appearance of the red blood cells is modulated by activity of the spleen.Spherocytes, schistocytes, and nucleated red blood cells may appear in the peripheral blood.Denatured hemoglobin removed by an active spleen may leave bite cells, identified by the arrows in this photomicrograph, suggesting the presence of G6PD deficiency. | View Page |
| Heinz body formation Heinz bodies are 1-3 um particles of denatured hemoglobin settling eccentrically, usually close to the red cell membrane. They are found in erythrocytes in unstable hemoglobin disorders, acute drug induced hemolysis, and following splenectomy. Their formation may be exaggerated by in-vitro incubation of a fresh blood sample with phenylhydrazine. Heinz bodies, as pictured here, are identified using a supra-vital stain, such as new methylene blue or cresyl violet. Bite cells, visible with Wright-Giemsa staining, are visual reminders that the spleen is functional and has pitted the aberrant chunk of hemoglobin from the circulating erythrocyte. | View Page |
| Leukoerythroblastosis Illustrated in this field is a normoblast and a myelocyte, representing leukoerythroblastosis, a term associated with the release of immature cells from a disrupted marrow. Metastatic disease in the bone marrow, particularly in patients with primary breast or prostate cancer, is usually the culprit. Leukoerythroblastosis in the absence of anemia or thrombocytopenia is a signal to search for cancer metastic to the marrow. Nucleated RBCs were not identified on the blood smear seen here but were detected by an automated analyzer.The mortality rate of elderly patients with increased NRBCs, especially following accidents or general surgery, is greater. | View Page |
| Smear with teardrop cells As previously mentioned, tear drop cells are present in disorders with altered splenic or bone marrow structure. Disrupted splenic cords and myelofibrosis with myeloid metaplasia are examples. Tear drop cells appear in the peripheral blood as a response to red cell alterations by thalassemia when red cell inclusions are expelled by a stripping process through splenic cords. A marrow disrupted by malignant cells may also set the stage for release of teardrop cells into the peripheral blood. Importantly, teardrop cells may arise as an artifact of improper smear preparation, identified by their uniformity in pointing in the same direction. In contrast, teardrops noted in the photograph are irregularly arranged and oriented in various directions. Teardrops always have pointed ends and disappear after splenectomy. | View Page |
| Cardiac hemolysis (Waring Blender Effect) Two photographs of a peripheral blood smear are submitted for review . The smears are from a 9-month-old baby with a heart valve replacement. In the upper photograph is a nucleated RBC and platelets are decreased. Nucleated red cells and occasional giant platelets indicate an active marrow response. In the process of forcing blood cells through the heart valve, erythrocytes are damaged, schistocytes are formed, and platelets are destroyed leading to thrombocytopenia. In the lower field are schistocytes, acanthocytes, echinocytes (burr cells), spherocytes, and the absence of platelets. The presence of burr cells could represent an artifact of smear preparation, but with the history of valve replacement, the red cell changes are likely the result of red cell damage as the cells circulate through the new valve. This situation is described as Waring Blender Effect because of damage to blood cells passing through the new valve, looking as if they had suffered the onslaught of a blender. Target cells and mild hypochromia may reflect iron deficiency through the loss of iron from destruction of RBC's. Iron loss through red cell destruction may be reflected in some hypochromia. | View Page |
| A 5-year-old girl was brought to a physician's office because of fever and viral-type illness symptoms. Her blood pressure was elevated.Hemogram: hemoglobin 9.1g/dL (normal 12.0 - 16.0 g/dL), hematocrit 28% (normal 37 - 48%), MCV 80 fl (normal 86 - 98 fl), RDW 13.1% (normal 11 - 15%), platelets 90.1 X 109/L (normal 150 - 450 X 109/L) WBC 9.6x109/L (normal 4.3 - 10.8 x 109/L).The peripheral blood smear is represented in the photograph.Which of the following are the most likely associated conditions? | View Page |
| A 10-year-old child presents with jaundice and scleral icterus. The photograph captures a section of the peripheral blood smear. The report should direct attention to: | View Page |
| Considering the predominance of microspherocytes on the blood smear, and the patient's jaundiced condition, what is the most likely diagnosis? | View Page |
| A peripheral blood smear was submitted for review. The presence of sickle cells and target cells as shown is diagnostic of hemoglobin SC disease. | View Page |
| Atypical smear: Case follow-up The patient whose blood smear is shown in the photograph was a 32-year-old female from Virginia who came to the high country of Colorado to ski. The day after arrival, she experienced shortness of breath, fatigue, and upper abdominal pain. She was seen in a medical center in the mountains where a working diagnosis of altitude sickness was made. A CBC revealed RBCs 5.1 x 1012/L, hemoglobin 12.8g/dL, MCV 60fL, hematocrit 40.9%, and normal total WBC, differential, and platelet count. The RDW was normal. Further questioning revealed a previous diagnosis of heterozygous beta-chain thalassemia. No other abnormal hemoglobins were found on hemoglobin electrophoresis, but HbA-2 was elevated to 5%, supporting the diagnosis of beta thalassemia. The patient's poikylocytosis and anisocytosis may be a clue to an underlying erythrocyte abnormality. Persons with iron deficiency anemia may experience various degrees of hypoxia upon arriving at high altitudes. Those with sickle cell disease and thalassemia minor (as in this case) may experience bone pain or other symptoms of "crisis" and/or alteration in the appearance of their erythrocytes upon sudden high altitude exposure. The classic teaching is that in differentiating iron deficiency anemia from thalassemia, increased RDW would favor iron deficiency; normal RDW favors thalassemia. | View Page |
| The photograph here is of a peripheral smear sent for hematologic review. No clinical information for the patient was sent with the slide. What is the first course of action that the reviewer should take to assist him/her in interpreting the findings on this blood smear? | View Page |
| The photograph is representative of the peripheral blood smear of a five-month-old immigrant from Asia. Her mother was concerned that the child was not eating well. Her spleen was palpable.The hemogram revealed the following:Hb 9.6g/dL (normal 12.0 - 16.0 g/dL)RBC 5.48 X 1012/L (normal 4.2 - 5.9 X 1012/LHCT 30.4% (normal 37 - 48%)MCV 55.4 fl (normal 86 - 98 fl)MCH 17.5 pg (normal 27 - 32 pg)MCHC 31.6 g/dL (normal 31 - 37 g/dL)RDW 34.9% (normal 11 - 15%)Reticulocyte count 10.9% (normal 0.5 - 1.5%)Select the most likely diagnosis based on the clinical information and peripheral blood findings. | View Page |
| The patient, an 8-month-old girl, was anemic, jaundiced, and had splenomegaly. Her family had immigrated from the Middle East. Based on the history and the peripheral blood picture, the most probable diagnosis is thalassemia. | View Page |
| Rouleaux Rouleaux formation correlates with an increased concentration of serum monoclonal proteins. Rouleaux may be seen as an artifact in the thicker portions of blood smears. The addition of a drop of saline to the blood smear will serve to disperse any artifactual rouleaux formation. The presence of rouleaux formation or RBC agglutination may result in a falsely decreased electronic red blood count and falsely increased MCV, as these clusters may be read as one cell. | View Page |
| The arrangement of erythrocytes on this peripheral blood smear may be seen in each of the following conditions except: | View Page |
| Dimorphic RBC population Illustrated in the photomicrograph of a peripheral smear are two populations of erythrocytes. Approximately 50% of the erythrocytes are normal size and contain a full complement of hemoglobin. The patient had received blood transfusions. The transfused red blood cells are the normocytic, normochromic red cells. Admixed are microcytic erythrocytes and larger erythrocytes, some faintly mottled or smudged, suggestive of reticulocytes. This picture represents a hemolytic process with a reticulocyte response. A similar dimorphic red cell population appears following erythropoietin therapy. It is important to recognize when a population of cells in the peripheral smear is not in context with anticipated laboratory findings and the clinical situation. | View Page |
| A blood smear represented by the photograph was submitted for hematologic review. Based on the erythrocyte morphology and the accompanying histogram, which of the following choices is the most likely situation or condition? | View Page |
| Hereditary ovalocytosis and elliptocytosis Ovalocytes are rod shaped erythrocytes with nearly parallel lateral walls. If the long axis of an erythrocyte is no more than twice as long as the short axis, the cell is an ovalocyte. If the long axis is more than twice as long as the short axis, the cell is an elliptocyte. Hemoglobin tends to collect at each end of these cells. The ends of the cells are rounded and never pointed, to be differentated from sickle cells. Ovalocytes present in greater than 25% of red cells on the blood smear are characteristic of hereditary ovalocytosis. The oval shape is attributed to a defect in horizontal red cell membrane protein interactions. Lesser numbers of circulating ovalocytes may be present in various anemias including megaloblastic, sideroblastic, iron deficiency, and in thalassemias. A rare ovalocyte (less than 1%) may be found on almost any peripheral blood smear. Resistance to malarial infection may be a beneficial attribute of hereditary ovalocytosis. | View Page |
| Stomatocytes Stomatocytes are erythrocytes with a slit-like central pallor. Otherwise, they resemble typical RBC's in size and shape. Unless 10% or more of the RBC's are stomatocytes, their presence is probably artifactual. Stomatocytes form at a low blood acidic pH as seen in exposure to cationic detergents, and in patients receiving phenolthiazine. Hereditary stomatocytosis has some resemblance to hereditary spherocytosis, as stomatocytes may develop into spherocytes with further metamorphosis. In hereditary stomatocytosis, mild anemia and findings of on-going hemolysis should be evident if the condition presents as a clinical problem at all. | View Page |
| The blood study from which this smear was obtained revealed an MCV of 115 femtoliters (fl).Normal MCV values in adults= 80 - 90 fl.Normal MCV values in full-term infants= 98 -108 fl.Which of the following conditions may be indicated by the results seen on this peripheral blood smear? | View Page |
| Reporting of laboratory data in regard to blood cell abnormalities Laboratory data must be presented to clinicians in a user friendly way to promote effective decision making. Databases must be designed to provide clear information that leads quickly to the best patient care outcome. We continue learning how to collect and retrieve laboratory data from our machines, but we are not always in tune to how entry and retrieval of data is geared to and, more directly, influences patient care outcomes. Examples of blood cell abnormalities on a peripheral blood smear that may immediately direct the physician to a specific diagnosis are: (1) presence of target cells as found in thalassemia or hemoglobinopathies and target cells in liver disease, particularly with obstructive jaundice; (2) burr cells as a signal of chronic renal disease and uremia; and (3)atypical neutrophil inclusions relating to genetic disorders. Critical appraisal of such observations could add valuable clues for a diagnosis. Laboratory professionals must establish a set of principles for orderly observation of blood cell morphology, have a clear vision of the applications of their work, and understand the potential clinical implications of their reports and interpretations. Emphasis on values and relevance focuses on patient care outcomes and their dependency on prompt availability of results and contextual interpretations. | View Page |
| Criteria for peripheral blood smear review Initial analysis of the peripheral blood picture is made in most clinical laboratories with an automated instrument. Samples are selected for further analysis when quantitative or qualitative abnormalities beyond a defined standard are found. The following are examples of quantitative RBC abnormalities that may prompt a blood smear review. Each laboratory, however, should develop its own guidelines: Hgb: < 8 or >18 g/dL (<10 or > 21g/dL in a newborn)Hct: <20% or > 60% in adults (<40% or >65% in a newborn)MCHC: <29 g/dLMCV: <69 femtoliters (fl) or >110flFlags generated by the hematology analyzer that indicate possible red cell abnormalities or spurious resultsAny of these findings should be followed up with a peripheral blood smear review. | View Page |
| Guidelines for standard reports In a study on the reporting of red blood cell morphology abnormalities conducted in Ontario, Canada (Hookey L, Dexter D, Lee DH, Laboratory Hematology 7:83-88, 2001), fewer than 50% of 33 participants used the same term to describe the quantitative frequency of peripheral blood abnormalities. Seven blood smears, each containing one of several abnormal erythrocytes-- schistocytes, teardrop cells, acanthocytes, and Howell-Jolly bodies--were evaluated by 32 participants. The participants were asked to document their evaluations from a list of quantitative terms. There was a heterogeneity in the use of terms "rare," "slight," "occasional," "few," "mild", "present," "moderate," "many," and "marked." Choices of terms were subjective without points of reference. Guidelines for establishing standardized qualitative estimations of abnormal erythrocytes in the peripheral smear are presented as follows: 1+ = 2 - 4/Oil Immersion Field (OIF) 2+ = 5 - 7/OIF 3+ = 8 - 10/OIF 4+ = >10/OIF. The terms "few," "moderate," "many," and "marked" may be substituted for the 1+ - 4+ grading system, but only when their specific points of reference are universally understood in tandem with the above guidelines. A comment should be triggered if any erythrocyte abnormalities are seen in numbers >3/OIF including, but not limited to, polychromasia, basophilic stippling, nucleated RBC's, and Howell-Jolly bodies. Rouleaux or RBC agglutination are important findings and must be documented. | View Page |
| You have been asked to review a peripheral blood smear. You note >10/OIF (oil immersion field) echinocytes (burr cells). Which of the following actions would be the most appropriate response? | View Page |
| What is Venipuncture? Venipuncture is the collection of blood from a vein. The person having the responsibility for the performance of the venipuncture may be a phlebotomist who is a part of the laboratory staff, or he/she may be another healthcare professional that has been trained to perform this duty. In this course, we will refer to the person performing the venipuncture as the phlebotomist. | View Page |
| Explore the Possibilities! The antecubital area of the arm is usually the first choice for routine venipuncture. This area contains the three vessels primarily used by the phlebotomist to obtain venous blood specimens: the median cubital, the cephalic and the basilic veins.Although the veins located in the antecubital area should be considered first for vein selection, there are alternate sites available for venipuncture. These include the top of the hand, the side of the wrist, and the forearm. These sites should only be considered after determining that the veins of the antecubital area cannot be accessed or cannot be used. Vein Location Reason for Choice Placement Direction Median Cubital Mid antecubital fossa Vertical to diagonal Musculature assists in stabilizing vein; very often largest; ease of access Cephalic Thumb side of antecubital fossa Vertical Ease of access; few nerves and tendons in area Basilic Body side of antecubital fossa Vertical to diagonal More difficult to access; proximity of artery, nerves and tendons. Use this vein only as the final alternative. | View Page |
| Pre-analytical Errors Preanalytical Error What is it? How does it happen? What is the result? Hemolysis Red blood cells (RBCs) break and release contents of cell into plasma. Needle incorrectly positioned in vein; cells forced to squeeze through opening. Needle gauge too small; slow blood return into tube. Vigorous mixing or shaking of tube. Alcohol on skin that has not had sufficient time to dry. Some test results may be falsely elevated. (Potassium is especially affected by hemolysis.) Patient may have to be re-drawn. Clotted specimen Clumped or clotted cells in specimen that requires anticoagulated or whole blood Insufficient mixing of blood with anticoagulant in tube. Delay in mixing tube. Slow filling tube. Inaccurate test results for cell counts and clotting studies. Patient may have to be re-drawn. Tube filled to incorrect volume Too little or too much blood in tube. Tube removed from needle too quickly. Vacuum in tube has been compromised due to use of tube past the expiration date (Results in a short fill). Manual fill of tube may lead to over-fill. Test results may be unreliable due to dilution errors. Patient may have to be re-drawn. | View Page |
| Proper Patient Identification In order to prevent errors that affect specimen quality, the phlebotomist must pay close attention to detail during the entire venipuncture process. All steps of the phlebotomy procedure must be included for every venipuncture. This will help to maintain specimen integrity during the collection, transport, and handling of blood specimensProperly identify the patient every timeThe phlebotomist is responsible for correctly identifying the patient using two unique patient identifiers that include the patient's complete first and last name, medical record or hospital number, and/or date of birth. The patient location or room number, bed tag and chart are not reliable forms of identification and should not be used for patient identification. Every patient must verbalize his/her name to the phlebotomist, if able to do so. It is unacceptable for the phlebotomist to ask the patient to confirm his/her name that was verbalized by the phlebotomist. For example, the phlebotomist should say, "Would you please tell me (or spell) your name and birthdate. " The phlebotomist should NOT say, "Are you Sally Brown, and is your birthdate June 1, 1925?" If this is a hospital inpatient, check the information on the patient's wristband and confirm that the name and hospital number or medical record number matches the patient information on the test order. Never rely on identification attached to a bed, chart or door. NEVER draw a patient whose identity is not established or is in conflict. If there is a discrepancy, the phlebotomist must STOP and seek assistance to have the discrepancy resolved before proceeding with the venipuncture. If this is an outpatient that does not have a wristband, ask the patient (or guardian/caregiver) to state the patient's date of birth. A picture ID, such as a driver's license, can also be used for positive patient identification. | View Page |
| What is a Hidden Error? Hidden errors are those that cannot be detected or corrected by the laboratory analyst prior to testing. Most often these errors can be prevented by the phlebotomist following correct venipuncture procedure for every procedure, every time.Hidden errors include hemoconcentration, incorrect order of draw, and (the most serious of all errors) misidentification of patient or specimens. Because these errors often are unknown, the analyst may inadvertently report erroneous patient results which could be harmful to the safety and well-being of the patient. Condition What is it? How does it happen? What is the Result? Hemoconcentration Blood pools at site of venipuncture Tourniquet is applied for a prolonged period of time Test results may be inaccurate because blood components move between blood and tissues Pouring Blood between tubes Mixing contents of two or more tubes Removing top of tube to combine contents of one tube with another Inaccurate test results due to over or under dilution or incorrect anticoagulant Clots form due to lack of mixing Patient may have to be redrawn Incorrect patient identification and incorrect specimen labeling Using the wrong name to label a specimen Failure to positively identify EVERY patient using 2 unique identifiers BEFORE beginning venipuncture Failure to label EVERY specimen in the presence of the patient Failure to concentrate fully on the task Results reported to caregiver for wrong patient Compromises patient care; may be life-threatening | View Page |
| Correct Fill Fill blood collection tubes completely (until vacuum is exhausted) to ensure the correct blood to anticoagulant ratio necessary for accurate patient results. Specimens may be rejected by the laboratory if the tube is short-filled or over-filled. To avoid short-filling of tubes, the phlebotomist must ensure that the blood flow stops completely before removing the tube from the needle. When using a winged device (butterfly) to collect blood for coagulation studies (e.g., protime, aPTT), the phlebotomist must draw a light blue top "waste" tube before attaching another light blue top tube for testing. If the air in the tubing of the winged device is not displaced into a waste tube and is drawn into the tube used for testing, the tube used for testing will short-fill. The laboratory may reject the specimen because of invalid blood to anticoagulant ratio. | View Page |
| Do Not Tamper With the Specimens A phlebotomist should not uncap a blood tube and pour blood between tubes or combine two partially filled tubes of blood into one. This may lead to over-fill of tubes and more importantly, invalid patient results. Combining two tubes with the same additive into one tube will alter the blood to anticoagulant ratio by doubling the amount of anticoagulant in the tube. When blood is being transferred from a syringe to a tube, the phlebotomist must not apply pressure to the plunger to force blood into the tube. This may cause over-filling of the tube and hemolysis of blood cells. With the aid of a transfer device, the tube will draw the amount of blood required to fill the tube based on the amount of vacuum in the tube. | View Page |
| Avoid Prolonged Tourniquet Time A prolonged tourniquet time may lead to blood pooling at the venipuncture site, a condition called hemoconcentration. Hemoconcentration can cause falsely elevated results for glucose, potassium, and protein-based analytes such as cholesterol.Ideally, the tourniquet should be in place no longer than one minute to prevent hemoconcentration. If the phlebotomist takes longer than one minute to assess and locate vein of choice for venipuncture, it is best practice to release the tourniquet, assemble supplies and reapply tourniquet immediately before needle insertion. | View Page |
| Order of Draw Blood collection tubes must be filled in a specific order to avoid specimen contamination from the additive in the preceding tube. The following order of draw is an accepted laboratory standard. 1. Tubes or bottles for blood cultures 2. Light-blue top tubes (sodium citrate) 3. Serum tubes (with or without clot activator) 4. Green top tubes (sodium or lithium heparin) 5. Lavender or pink top tubes (Potassium EDTA) 6. Gray (Sodium fluoride and sodium or potassium oxalate) | View Page |
| Importance of Using the Correct Blood Collection Tube Specific anticoagulants must be used for each test that requires plasma or whole blood. If the blood is drawn into a tube with the wrong additive, patient results may be adversely affected. For example, the test for lithium usually requires a serum sample. If instead of a serum tube, the phlebotomist used a tube that contained lithium heparin, the lithium result for the patient would be falsely elevated. It is imperative that the phlebotomist use the tube with the correct additive to avoid erroneous patient results. | View Page |
| Pre-analytic and hidden errors can greatly affect a laboratory result.Match the error listed below with the cause from the drop-down box. | View Page |
| Protect Yourself The safety of both the phlebotomist and patient is of utmost concern at all times. In the unfortunate event of an accidental needlestick or if you get blood or other potentially infectious materials in your eyes, nose, mouth, or on broken skin, immediately flood the exposed area with water and clean any wound with soap and water or a skin disinfectant if available. Report this immediately to your employer and seek immediate medical attention. It is imperative that the phlebotomist follow facility protocol for reporting the incident. This ensures prompt treatment for the injury. The facility procedure must be followed whether the accidental puncture was from a clean or contaminated needle.The single most important element to prevent an accidental needlestick is for the phlebotomist to fully concentrate during every procedure. Keeping your mind on the task at hand contributes to a successful and safe result. | View Page |
| References Clinical and Laboratory Standards Institute (CLSI). Collection, Transport, and Processing of Blood Specimens for Testing Plasma-Based Coagulation Assays; Approved Guideline. Fourth ed. CLSI document H21-A4. NCCLS. Wayne, PA: 2003.Clinical and Laboratory Standards Institute (CLSI). Procedures for the Collection of Diagnostic Blood Specimens by Venipuncture; Approved Standard. Sixth ed. CLSI document H3-A6. NCCLS. Wayne, PA: 2007.Clinical and Laboratory Standards Institute (CLSI). Procedures for the Handling and Processing of Blood Specimens; Approved Guideline. Third Edition. CLSI document H18-A3. NCCLS. Wayne, PA: 2004.Ernst DJ. Applied Phlebotomy. Baltimore, MD: Lippincott Williams & Wilkins: 2005.Lowe B. Reinforcing safety sticklers. Advance for Medical Laboratory Professionals. May 2004; 16:2A-3A.The Joint Commission. Patient Safety-2009 National Patient Safety Goals. Available at: http://www.jointcommission.org/PatientSafety/NationalPatientSafetyGoals/. Accessed July 18, 2009. | View Page |
| Blood Collection Systems and Devices The phlebotomist has a choice of several blood collection systems. Three that are commonly used are discussed on the following pages. Evacuated Tube SystemThe primary choice for a routine venipuncture that will be performed on an adult or an older child is a blood collection system that consists of a holder (or adapter), a needle that is pointed on both ends, and evacuated blood collection tubes. One end of the needle will pierce the vein and the other end will pierce the stopper of the evacuated tube so that blood will flow into the tube to fill the vacuum. A safety device is required on either the holder or the needle to comply with current standards for needle safety. Two examples of needle holders equipped with safety devices are shown on this page. | View Page |
| Syringe The syringe and needle combination should be the last equipment option that is considered; it is not as safe a choice as the self-contained blood collection systems because it involves more manipulation. However, the phlebotomist may choose to use a syringe to prevent vein collapse if the phlebotomist thinks that the vein is too fragile to withstand the pressure exerted by the vacuum as it pulls blood into the collection tube. A transfer device aids in the safe transfer of blood from the syringe into blood collection tubes. During blood transfer, do not manually push plunger as this may cause hemolysis of the specimen. | View Page |
| Blood Tube Labeling Information Each tube used for blood collection is labeled by the manufacturer with important information. This information includes: tube volume in milliliters (mL), expiration date, lot number and, if applicable, the type of additive that is in the tube. Tube volume: Each tube contains a vacuum that allows a specific amount of blood to enter the tube. In a tube that contains an anticoagulant, the amount of blood that is drawn into the tube will establish the correct blood to anticoagulant ratio. Tubes not filled to the correct volume (over-filled or under-filled) may cause inaccurate test results. Expiration Date: An expiration date is stamped on all blood collection tubes. The tube manufacturer determines this date based on its studies of vacuum maintenance and anticoagulant effectiveness. The expiration date should be checked routinely; tubes that are past the expiration date should be discarded.If a blood collection tube is used past its expiration date, the vacuum may not draw the amount of blood needed to fill the tube completely. Short-filled tubes may not be acceptable for testing and the specimen would have to be recollected. If the tube contains an anticoagulant, it may not work effectively (may not prevent the blood from clotting). Lot Number: A lot number listed on the tube identifies a specific group of tubes that were manufactured at the same time. This information is important to know if a problem is identified with several collection tubes. If the defective tubes are all part of the same lot number, the manufacturer should be notified for replacement of the tubes. Additive: Most blood collection tubes contain a type of additive or chemical that, when mixed with the blood, will yield a specimen acceptable for testing. The various types of additives that are contained in blood collection tubes are discussed on the following page. | View Page |
| Blood Collection Tubes Most blood collection tubes contain an additive that either accelerates clotting of the blood (clot activator) or prevents the blood from clotting (anticoagulant). A tube that contains a clot activator will produce a serum sample when the blood is separated by centrifugation and a tube that contains an anticoagulant will produce a plasma sample after centrifugation. Some tests require the use of serum, some require plasma, and other tests require anticoagulated whole blood. The table below lists the most commonly used blood collection tubes. Tube cap color Additive Function of Additive Common laboratory tests Light-blue 3.2% Sodium citrate Prevents blood from clotting by binding calcium Coagulation Red or gold (mottled or "tiger" top used with some tubes is not shown) Serum tube with or without clot activator or gel Clot activator promotes blood clotting with glass or silica particles. Gel separates serum from cells. Chemistry, serology, immunology Green Sodium or lithium heparin with or without gel Prevents clotting by inhibiting thrombin and thromboplastin Stat and routine chemistry Lavender or pink Potassium EDTA Prevents clotting by binding calcium Hematology and blood bank Gray Sodium fluoride, and sodium or potassium oxalate Fluoride inhibits glycolysis, and oxalate prevents clotting by precipitating calcium. Glucose (especially when testing will be delayed), blood alcohol, lactic acid | View Page |
| A blood collection tube that has a light-blue top contains which of these anticoagulants? | View Page |
| Tourniquets, Alcohol, and Gauze A tourniquet is used by the phlebotomist to assess and determine the location of a suitable vein for venipuncture. Single-use, latex-free tourniquets are preferred but reusable tourniquets are acceptable. However, if the reusable tourniquet becomes contaminated with blood or body fluid, it must be discarded immediately to avoid the spread of harmful contaminants to other patients. Follow the guidelines established by your facility for cleaning reusable tourniquets.Proper application of a tourniquet will partially impede venous blood flow back toward the heart and cause the blood to temporarily pool in the vein so the vein is more prominent and the blood is more easily obtained. The tourniquet is applied three to four inches above the needle insertion point and should remain in place no longer than one minute to prevent hemoconcentration. If the tourniquet is used during preliminary vein selection, it is best to release the tourniquet after assessing the vein and while you are assembling your supplies. Reapply the tourniquet just before starting the venipuncture; it should then be released soon after the needle has been inserted into the vein and the blood flows into the first tube. If collecting multiple tubes, the tourniquet may remain in place until blood enters the last tube. | View Page |
| Cleansing the Venipuncture Site The product used most often to cleanse and disinfect the site prior to venipuncture is 70% isopropyl alcohol in towelette form. Alternative cleansing agents available are chlorhexadine gluconate (chloraprep) and povidone-iodine which are used mainly for collection of blood cultures, blood alcohol specimens, or when the patient is sensitive to alcohol.The alcohol should be applied using a circular target motion, as demonstrated in the image. This technique pushes the bacteria away from the inside of the venipuncture site to the outside. The alcohol must be allowed to air dry for approximately one minute prior to venipuncture to properly disinfect site, prevent hemolysis of the specimen, and avoid discomfort for the patient. Gauze should be used when applying pressure to the venipuncture site immediately after the needle is withdrawn. Adequate pressure to stop bleeding is crucial to avoid formation of a hematoma or bruise. Cotton balls should not be used to apply pressure to stop bleeding because the clot formed may be dislodged by residual cotton fibers as the cotton ball is pulled away from the site.Paper tape or a bandage is used to cover the wound after bleeding has stopped to prevent disruption of the clot. | View Page |
| Unacceptable Sites for Venous Blood Collection If the antecubital area of the patient's arm is compromised or inaccessible, an alternate site must be chosen for venipuncture such as the top of the hand or the thumb-side of the wrist. However, some sites must be avoided due to the risk of complications and/or unnecessary pain to the patient. | View Page |
| Performing a Venipuncture on an Arm Containing an Intravenous Line Blood that is drawn from a vein that has an intravenous (IV) line may be diluted by the IV fluid. This can ultimately affect the accuracy of the blood test results. Therefore, an arm containing an IV should not be used to draw blood specimens if it can be avoided. However, if there is no alternative and an arm with an IV line in place must be used for venipuncture, try to choose a site away from and below the location of the IV. Document that the venipuncture was performed distal to (below) an infusion site. If the only vein available is proximal to (above and near) the IV, these steps should be followed: Ask the patient's caregiver if the IV can be turned off for a short period of time. The IV should be discontinued for at least two minutes before the venipuncture. Apply the tourniquet between the IV site and the area of the venipuncture. Perform the venipuncture. Document that the venipuncture was performed proximal to an IV site and that the IV was discontinued for two minutes prior to specimen collection. Notify the patient's caregiver when the procedure is completed and be certain that she/he restarts the IV. | View Page |
| When to Use Hand Veins to Obtain Blood Sometimes the phlebotomist may decide that the antecubital area is not the best site for venipuncture. Reasons for this decision may include: Extensive bruising (hematomas) in the antecubital area Inability to "feel" a vein suitable for puncture Presence of an intravascular line (IV) or vascular access device Physical condition of the patientWhen the veins in the antecubital area cannot be used, the phlebotomist may choose to use a vein on the top of a hand. The veins in the hand are very near the surface and often very small and thin so the procedure must be performed carefully and cautiously. . | View Page |
| Handle With Care Equipment: To successfully enter a hand vein, the phlebotomist must choose equipment that will allow needle entry at a very small angle. A winged device with a small gauged needle of 3/4 inch length is most often used to obtain blood from a hand vein. A syringe is usually attached to the end of the tubing of this device. By using a syringe, the phlebotomist can control the amount of pressure on the vein and avoid vein collapse. Evacuated tubes may collapse a vein by exerting too much pressure on the delicate vein. If available, smaller tubes containing less vacuum may be used.Insertion angle: The angle at which the needle is inserted into a hand vein is smaller compared to the angle of needle insertion into veins of the antecubital area. When drawing from a hand, the needle should be inserted into the vein at approximately a 15 degree angle to allow easier access of the surface hand veins. By inserting the needle at this angle, the risk of the needle going "through" the vein and puncturing the bony structures underneath are reduced. | View Page |
| When assessing a vein in the hand, where should the tourniquet be placed? | View Page |
| Specimen Collection Procedure Following the approved order of draw, connect the first blood collection tube onto the needle by pushing the tube into the holder so that the tube stopper is pierced by the exposed end of the needle. Use the flanges of the holder to stabilize the needle while connecting the tube. After tube is filled completely, remove the tube, again using the flanges of the holder to stabilize the needle. Replace with the next tube and mix the removed tube immediately if it contains an additive. Release the tourniquet when blood enters the final tube. When the last tube is filled, pull it back off the needle before removing the needle from the vein. Remember: Fill tubes in correct order and to correct volume. If you suspect that a tube did not adequately fill, try another tube. | View Page |
| Julie Smith was a newly certified phlebotomist and had been working at Northwood Hospital for several months. As she approached room 825, she looked on her collection list to verify this was the correct room for her first collection. Indeed it was, even though there was no patient name on the door. Her collection list told her the patient in room 825 was a 55 year old male named John Ready. After knocking several times, Julie entered the room to find a middle aged man who appeared to be sleeping. Julie approached the patient and said, “Good day Mr. Ready. My name is Julie and I am from the lab. I need to draw blood for some tests ordered by your doctor.” The man awoke and seemed irritated as Julie repeated herself. The patient responded and told Julie to do whatever she needed to do so he could go back to sleep. Julie then proceeded with the venipuncture.What procedure did Julie not follow prior to performing the venipuncture? | View Page |
| Scenario Conclusion When the results on Mr. John Ready were called to the nurse, she was very surprised that the result of his CBC was normal. The nurse explained to the laboratory technologist that Mr. John Ready had a known diagnosis of lower GI bleeding. His hemoglobin had been very low for the past 24 hours because of the internal bleeding, and she thought it was very surprising that his hemoglobin had normalized so quickly without having received a blood transfusion. Mr. Ready’s doctor decided the patient should be redrawn to ensure a correct result. The nurse further questioned if the phlebotomist could possibly have drawn the wrong patient because earlier that day Mr. Ready had been moved to room 831, and room 825 was presently occupied by a patient named Walter Redding. If Julie had properly identified the patient by asking him to state his name and then checking the name and identification number on the wristband, she would have realized that the patient in 825 was the wrong patient. | View Page |
| Bobby Jones, a phlebotomist at Community Hospital, entered the room of Mrs. Mary Grayson with a physician's order to draw some blood work. After greeting Mrs. Grayson, identifying himself, and properly identifying the patient, Bobby prepared for the venipuncture.As he approached the patient's bed, he noticed a sign posted above the bed that read: “Restricted left arm usage. Previous mastectomy - Do no use left arm for venipuncture.” Bobby set up his equipment to use the patient's right arm and noticed an intravenous (IV) line in Mrs. Grayson’s right arm positioned in a vein slightly above her wrist on the dorsum (top) of her forearm.Which site should Bobby choose for the venipuncture? | View Page |
| A phlebotomist was collecting a STAT prothrombin time (PT) and complete blood count (CBC) on a patient when blood flow unexpectedly stopped. The lavender top tube being drawn at the time was less than one third full. The light-blue top tube had already been drawn for the prothrombin time.Before resorting to a second venipuncture, which of the following procedures should be attempted in order to adequately fill the lavender top tube? | View Page |
| Match the letters representing the peripheral white blood cells with the most likely associated clinical conditions. | View Page |
| The presence in the peripheral blood of an increased number of hypersegmented white blood cells as presented in the photograph serves as a marker for preleukemia. | View Page |
| Match the letter representing the cell type with the condition in which increased numbers of the cell may be found in the peripheral smear. | View Page |
| An increase in peripheral blood monocytes with an appearance similar to the cell in the photograph is highly suggestive of infectious mononucleosis. | View Page |
| The upper photograph of a bone marrow section reveals distinct hyperplasia with total replacement of marrow fat. A bone marrow smear stained with Wright/Giemsa is displayed in the lower photograph. Calculate the M:E ratio between myeloid and erythroid cells found in the lower photograph. The total peripheral blood white blood cell count was 5,400/cumm. This bone marrow architecture may be found in each of the following conditions except: | View Page |
| The upper photograph of this bone marrow section also reveals distinct hyperplasia with total replacement of the fat. The lower photograph is a Wright/Giemsa stain. Calculate the M:E ratio of the distribution of myeloid and erythroid cells in the lower photograph. The peripheral white blood count was 18,500/cumm. The most likely associated condition is: | View Page |
| Lymphocytes displayed in the photograph most likely would be called atypical or reactive. A quantitative estimate of the number of such cells may be useful using terminology such as mild (or 1+), moderate (2+) or many (3+). What percentage of the total white blood count would a report of moderate or 2+ atypical lymphocytes indicate? | View Page |
| Peripheral blood smear preparation A reproducible blood smear review requires every peripheral smear be prepared for consistent openness and clarity. Consistency is maintained by uniform handling of every blood smear. Good results may be expected when the preparation is begun with only a small drop of blood at one end of a clean glass slide. The drop is smeared lightly and quickly so as to leave a thin (feathery) edge where all cells may be examined individually, particularly red blood cells. The site of examination then is chosen away from clumping, piling, or bumping of cells against each other, perhaps a site five or six oil fields from the end of the feathery portion. Such an area for examination is illustrated in the photograph. | View Page |
| An electronic platelet count of 40,000/cumm was reported. Review of the peripheral blood smear(see photograph)reveals single platelets in open fields and platelet clumps. The platelet count is likely incorrect. | View Page |
| Platelet Estimate The findings in the photograph from a peripheral blood smear would elicit a report comment of "increased platelets" of some high magnitude, such as "marked" or "4+". Estimates of platelet counts from review of a peripheral blood should be made on each smear examined. This provides a simple estimate of "high" or "low" or corroborates the value generated from an electronic cell counter. A formula for estimating platelet counts must be established in each laboratory. Following is a guideline: 5/oil power field (OPF) = 100,000/cumm; each platelet thereafter = 10,000/cumm. Thus, if an average of 10 platelets/OPF are observed, the estimated platelet count is 150,000.cumm. Such a counting scheme for platelets when clustered as in the photograph is probably not needed, as there are more than 100 platelets in the field. This translates into a platelet count of 1 million/cumm or more. This peripheral smear observation, however, would serve to corroborate an electronic platelet count of 1.2 million/ cumm. | View Page |
| Criteria for evaluation of white blood cells and platelets In most clinical hematology laboratories, an initial blood count is performed by an electronic instrument. Some of these instruments also produce a differential blood count, and a platelet count. Instruments that provide a 3-part differential indicate the percentage of neutrophils, lymphocytes, and a mixed field group that includes monocytes, eosinophils, basophils, immature and atypical cells. Thus, the atypical cells shown in the photograph would be counted as mixed cells and a smear review would be needed to make an identification. Instruments providing a 5-part differential count include monocytes and eosinophils. In cases where the mixed cell count is high, or there are other indications that atypical cells may be present, a hematologist's review of the smear is indicated. | View Page |
| Typical cells on a peripheral blood smear as photographed here were repeatedly encountered as the smear was reviewed. The peripheral white blood cell count was 51,000/ml with an orderly maturation sequence. The comment "leukemoid reaction" may properly be appended to the report. | View Page |
| A peripheral blood smear with many myeloid cells (photograph) was presented for morphology review. Toxic vacuoles in the neutrophil and monocyte most likely represent: | View Page |
| Leukemoid reaction revisited The term leukemoid reaction is used to describe peripheral white blood cells that on the stained blood smear may have some resemblances to leukemia cells. Quantatively in a leukemoid reaction, the neutrophil count is >50,000 cumm with more immature cells, particularly myelocytes, than are usually present in toxic left shift syndromes. The presence of immature cells in a leukemoid reaction awakens thoughts of leukemia. Great care must be taken to make a distinct differentiation between aberrant white blood cell proliferations and a benign but exaggerated granulocytic proliferative response. Our material is from a 1-month-old girl with Down's syndrome. Her total white blood count was 37,000/mm3 interpreted as leukocytosis with left shift. Leukocytosis with a left shift, and leukemoid reactions with high alkaline phosphatase are conditions to be mindful of in patients with Down's syndrome. The alkaline phosphatase score is high in leukemoid reactions, low in granulocytic leukemia. | View Page |
| Familial disorders: summary Several additional familial and congenital disorders associated with atypical inclusions in WBCs are now recorded. These individual syndromes carry the following names: Fechtner, Alport, Epstein, Sebastian, and Paris-Trousseau.Fechtner syndrome( Peterson etal,Blood 65:397-406,1985)was described with 8 family members spanning 4 generations presenting with varying degrees of nephritis, deafness,and congenital cataracts. The syndrome is likely a variant of Alport syndrome with the addition of leukocyte inclusions and macrocytothemia. Several more cases involving other families have been reported. The inclusions resemble toxic Doehle bodies or those of the May-Hegglin anomaly by light microscopy, but are ultrastructurally unique.Alport syndrome in itself is autosomal dominant, X-linked , hereditary and characterized by sensorineural deafness and hereditary nephritis. It is believed to result from abnormal glycopeptide synthesis in renal basement membranes. Recurrent hematuria and slowly progressive renal insufficiency are clinical findings. Cataracts and platelet abnormalities may be added features.Epstein syndrome is essentially Alport syndrome with the addition of macrothrombocytopenia (Seri, et al. Hum Genet 110:182-186, 2002). Neutrophil inclusions are absent in this disorder; neutrophilic inclusions are considered part of the Fechtner syndrome. The Sebastian platelet syndrome is a variant of hereditary macrothrombocytopenia combined with neutrophil inclusions that differ from Doehle bodies, but are similar to those inclusions in Fechtner syndrome. (Greinacher, et al, Blut 61:282-288, 1990).Paris-Trousseau syndrome includes large platelets containing giant alpha granules identifiable in the peripheral blood.(Breton-Gorius, Blood 85:1805,1995) | View Page |
| The inclusions noted in the cytoplasm of this band neutrophil are most suggestive of: | View Page |
| Alder- Reilly Anomaly Large inclusions in leukocyte cytoplasm appear with Alder-Reilly syndrome. Inheritance patterns are not completely clear. The condition is characterized by larger than usual azurophilic and deeply violet staining granules clustered throughout the cytoplasm (even covering the nucleus)in all granulocytes. There are variations in which some lymphocytes and monocytes may be affected. These inclusions represent partially degraded mucopolysaccharides within lysosomes.Alder-Reilly bodies may be found independently of genetic mucopolysaccharidoses as an inherited anomaly (Jordan's anomaly). Cytoplasmic vacuoles of toxic origin are not present in Alder-Reilly cells. The background condition in Alder-Reilly syndrome is mucopolysaccharidosis with various types of bone and cartilage disorders, reported first in gargoylism, then in Hunter and Hurler syndromes. Accompanying conditions are hepatosplenomegaly, corneal opacities, and mental retardation. Reference: Brunning, Richard D. Morphologic Alterations in Nucleated Blood and Marrow Cells in Genetic Disorders. Human Pathol: 99-124, March, 1970 | View Page |
| WBC inclusions: summary The presence of atypical inclusions within the cytoplasm of neutrophils and other leukocytes should lead to a clinical investigation of the setting for these findings.Atypical neutrophil inclusions may be seen in the following disorders: Chediak-Higashi syndrome, May-Hegglin anomaly, Alder-Reilly anomaly, Fechtner , Sebastian, Epstein and Alport-like syndromes and in infectious and toxic conditions (in the form of Doehle bodies).Although a specific entity may not be evident from examination of the peripheral blood alone, it is important that hematology technologists include a comment reporting on the presence of these inclusions or granules. A clinical investigation with further hematologic and genetic studies may then appropriately be considered.Many of the disorders with atypical neutrophil cytoplasmic granules are also associated with platelet abnormalities, particularly giant platelets (lower photograph).Therefore, when atypical granules are recognized, scanning of the peripheral blood smear for atypical platelets may be revealing. These observations serve as readily identifiable markers for acquired and genetic human maladies, and as a guide for unraveling the reasons for a patient's suffering and impaired health. | View Page |
| The pale-staining cytoplasmic bodies marked by the arrow in the photograph may be seen in each of the following conditions except: | View Page |
| Case History A 17-year-old young woman was admitted to the hospital with abdominal pain and a tentative diagnosis of appendicitis.The total white blood count was 14,500 cells/cumm with a left shift and neutrophils with changes tagged by the arrow in the photographs (see blue arrow).The bluish-staining, blurred accumulations in the cytoplasm (Doehle bodies), are located at the cell periphery in neutrophils with toxic changes.Doehle bodies are remnants of endocytoplasmic reticulum and are products of cytokine activity in the induction and shortened activity of neutrophil activation.They are often present in conditions with increased neutrophil lysosomal activity, manifest as toxic granulation.In this case, the presence of Doehle bodies serves as markers for infection-induced leukocytosis and supports the diagnosis of acute appendicitis. | View Page |
| Eosinophilia Follow-Up As mentioned on the previous page, high percentages of eosinophils may be present in the peripheral blood smears of patients with a variety of conditions--asthma, urticaria, Loeffler's syndrome, larval parasitic infections and in chronic eosinophilic leukemia. One exception to the association of eosinophilia with parasitic infections is a fatal case of disseminated strongyloidiasis reported many years ago by Miale (Hematology--5th Edition, Mosby, pg. 776, 1977) in which the peripheral blood eosinophilia was masked by the administration of corticosteroids. | View Page |
| The neutrophil on the peripheral blood smear in this photograph is a mast cell. | View Page |
| Basophils A basophil and a small lymphocyte are compared in the same field of the upper photograph, A single basophil is shown in the lower photograph.The cytoplasmic granules of the basophil are larger than the granules of toxic granulation.They contain chemical mediators of immediate hypersensitivity, and are found in the cytoplasm and overlying the nucleus (better seen in the lower photograph). Basophilic granules stain metachromatically with toluidine blue indicating the presence of acid mucopolysaccharide or proteoglycans, both thought to be heparin or heparin-like substances.Basophils are related to tissue mast cells, each involved in hypersensitivity responses and following anaphylactic episodes.Under the stimulation of complement components C3a and C5a, many mediators are released from the basophil granules, including histamine, heparin, and eosinophil chemotactic factors of anaphylaxis, or ECF-A.Basophils are the least common neutrophils in the peripheral blood, comprising 2% or less of the differential count.The presence of large granules of irregular size in basophils and the admixture of eosinophilic granules may indicate dysplastic changes associated with myelodysplastic disorders and leukemia. | View Page |
| A peripheral blood smear is submitted for morphology review. The patient is a 10 year-old boy with symptoms suggesting appendicitis and an appendectomy is being considered. The total WBC is 18.5 X 1000/uL, RBC's = 5.45 X 1M/uL, hemoglobin = 16.0 g/dL, hematocrit 48.2%;wbc differential: Segs = 53%, bands = 42% (two of which are shown in the photograph), monocytes = 2%, and lymphocytes= 2%. These findings support the diagnosis of appendicitis. | View Page |
| Erythrophagocytosis Illustrated in the photograph is a phagocyte devouring several erythrocytes.This uncommon phenomenon occurs in the bone marrow and in the spleen as part of the process of erythrocyte destruction. Erythrophagocytosis is found in histological sections of the spleen in cases of hemolytic anemia.This phenomenon appears also in splenic sections in lupus erythematosis, and in rheumatoid arthritis.Our example is from a patient with a myeloproliferative disorder and is a rare example of a circulating erythrophagocytic cell in the peripheral blood. | View Page |
| The large blue staining cells represented here in the photographs comprise 50% of the total white blood count.This picture is most consistent with: | View Page |
| More about lymphocytes, their impostors and varied faces In this photograph of blood cells from yet another submitted slide, we find cells resembling lymphoblasts with increased nuclear/cytoplasmic ratios and dense, finely meshed nuclear chromatin. In addition, note the extrusion of delicate strands of cytoplasm from the outer cell membranes (blue arrow). These are cells connoting hairy cell leukemia (HCL). Under scanning electron microscopy, the cytoplasmic extensions appear to be either slender microvilli or delicate pseudopods. The most helpful confirmatory finding is the detection of acid phosphatase isoenzymne 5 in the cytoplasm of suspected hairy cells by staining. The enzyme concentrates primarily in golgi bodies and in the nuclear membrane and its staining is not inhibited by the addition of tartrate. Stated in another way, hairy cells on the peripheral smears are detected by their staining positively for tartrate-resistant acid phosphatase. Be suspicious of HCL if marrow resists aspiration-a consequence of reticulin fibrosis of the marrow in HCL. | View Page |
| Case History 2 An 80 year old man was seen in the emergency room with sudden onset of right sided chest pain accentuated on inspiration. His cough was productive of yellow sputum, and he was short of breath.His temperature was 101.2F. A chest X-ray revealed right middle lobe pneumonia. His hemoglobin was 15.2 gm/dl, HCT 44%, and RBC 4.5 m/ml. The white blood count was 35,000/cuml, with 45% neutrophils, 20% bands, 5% lymphocytes, 3% eosinophils, 2% basophils, and 25% atypical monocytes as noted in the photograph.The atypical monocytes had abundant blue-grey cytoplasm with a few scattered vacuoles, which, in company with toxic neutrophils appeared to be a response to infection.The patient had a past history of tuberculosis which may account for the monocytosis. | View Page |
| Multiple myeloma Plasma cells are uncommonly observed in the peripheral blood smear.They are normal constituents of lymph nodes, spleen, connective tissue and bone marrow. The presence of plasma cells in the peripheral blood is indicative of a large number of conditions mostly related to infections , immune disorders, malignancies, toxic exposures, hypersensitivity reactions and their responses.Although mature plasma cells have a distinct appearance, they still may be confused morphologically with immature plasma cells and other cells with inclusions, reactive changes or nucleated red bloods cell with altered identities.In the upper and lower photographs are plasma cells with features mindful of myeloma cellsThe large myeloma cell in the upper photograph has an eccentric immature nucleus with a muddy chromatin pattern.Note also clumping and stacking of the erythrocytes, bordering on rouleaux formation ,implicating an increase in plasma gamma globulin.The plasma cell with the double nucleus in the lower photograph is particularly suggestive of myeloma.Further studies are in order including a bone marrow examination where at least 30% of bone marrow cells should be variations of mature and immature plasma cells.Serum electrophoresis will reveal a monoclonal globulin spike, and light chains in excess of 1.0 gm/24 hours may be seen in the urine.The presence of lytic bone lesions is a convincing clinical clue.With these findings in combination, a diagnosis of myeloma can be made with assurance. | View Page |