Saline Information and Courses from MediaLab, Inc.

Most are IgM and not clinically significant May interfere with detection of clinically significant antibodies if they react at AHG phase. Screen cells and panel cells will have positive reactions in IS phase and strength will diminish or antibody will not be detected at AHG phase. Auto control will be positive if the cold antibody is an autoantibody. Binding of antibody to antigen occurs at room or colder temperatures and may start to disassociate from the red cell membrane at warmer temperatures. Reactions will appear weaker or be negative at warmer temperatures. (Example: 4+ at IS phase and W (weak)+ at AHG phase.) PrewarmingIf a non specific cold antibody or cold agglutinin is suspected, warm the sample and testing reagents, including saline, to 37° C. Only do reaction readings at AHG; bypassing the optimum reaction temperature prevents activation and binding of the cold antibody .

Monospecific anti-human globulin (IgG) enables sensitized red cells to cross-link so that agglutination is visible.Enhancement media are sometimes used to further promote agglutination and reduce incubation time. Low ionic strength saline (LISS) is the most common enhancement media. LISS reduces the ionic strength in the testing sample and causes reduction of the zeta potential. It increases antibody uptake and decreases incubation time. Polyethylene Glycol (PEG): brings red blood cells (RBCs) closer together and concentrates antibodies by removing water molecules from the testing sample. It is the most sensitive of the enhancement media; strengthening almost all clinically significant antibodies. However, it will also enhance some clinically insignificant antibodies as well. Centrifugation should be avoided when PEG is used. PEG can cause aggregates to form if the sample (red cell - serum mixture) with PEG added is centrifuged. Reaction readings should only be done at the AHG phase. 22% Albumin: reduces zeta potential, bringing the RBCs closer together and enhancing agglutination. Albumin does not contribute much to antibody uptake. Longer incubation time is needed with this media than with the previously discussed media. Detection of some IgG antibodies can be enhanced with enzyme test methods. Proteolytic enzymes (papain and ficin) denature some RBC antigens and remove negative charges from the RBC membranes. This reduces the zeta potential, bringing the cells closer together. Enzyme techniques are particularly useful in the identification of Rh antibodies and antibodies in the Kidd, Lewis, P and I systems. However, enzymes destroy some antigens including Fya, Fyb, M, and N. The effect of proteolytic enzymes on the S and s antigens are variable.

There are several diluents that may be used for CSF counts. Normal saline should be used to make dilutions for total cell counts. Diluting fluids for WBC counts include:crystal violet/acetic acidgentian violet/acetic acidtoluidine blue 0 and saponinThese fluids stain the white cells and lyse the red cells. The red cell count can be obtained by subtracting the white cell count from the total count. Low power (10x) may be used for the total count while the high power objective (40x) is suggested for the white cell count, especially if the white cells are to be differentiated into segs, lymphs and monocytes.

The specimen of choice for coagulation testing is plasma. Venous blood is drawn into a 3.2% buffered sodium citrate tube (blue top tube), yielding a whole blood sample with a 9:1 blood to anticoagulant ratio. Inadequate filling of the collection tube will decrease this ratio, and may affect test results. A blue top tube used for coagulation testing should be drawn before any other tubes containing additives. This includes tubes containing other anticoagulants and/or plastic serum tubes containing clot activators. A serum tube that does not contain an additive can be collected before the blue top tube. If a winged blood collection set is used in drawing a specimen for coagulation testing, a discard tube should be drawn first. The discard tube must be used to fill the blood collection tubing dead space to assure that the proper anticoagulant/blood ratio is maintained, but the discard tube does not need to be completely filled. The discard tube should be a nonadditive or a coagulation tube. If a blood specimen used for coagulation testing must be collected from an indwelling line that may contain heparin, the line should be flushed with 5 mL of saline, and the first 5 mL of blood or 6-times the line volume (dead space volume of the catheter) be drawn off and discarded before the coagulation tube is filled.

Give first aid. Wash needlesticks and cuts with soap and water. Flush splashes to the nose, mouth, or skin with water. Irrigate eyes with clean water, saline, or sterile irrigants. Report exposure to supervisor.

Joe has worked in the Blood Bank for 10 years. He will retire next week and Sara will fill his position. One of the tasks that Joe routinely performed was replacing the 10 liter saline cube located on the technical workbench. However, Sara realizes that she cannot safely lift the 10 liter cube and place it on the benchtop.An employee's stature and lifting capabilities are important variables in a physical task. Since the employee cannot physically change, other solutions must be considered. This situation is easily resolved by changing the size of the container in use. Ergonomic solutionThe Blood Bank will begin using 5 liter saline cubes that can be easily lifted by all members of the staff. The Blood Bank will also aquire a cart or hand truck for other heavy items. This scenario demonstrates that a change in staff may require ergonomic action to prevent injury.

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.