| Atherosclerosis continued If a plaque ruptures it will expose sub-endothelial tissue to blood cells and in so doing stimulate the formation of a clot. The clot is the body's attempt to seal off the crack but the clot itself can cause further obstruction to blood flow. This sudden increase in the blockage caused by the raised ruptured plaque and associated clot can transform a mild blockage into a critical one within a matter of hours. If it occurs within the blood vessels of the heart, the decrease in blood flow leads to severe and prolonged chest pain known as unstable angina. Such a patient is at obvious risk for a myocardial infarct should the blockage become any worse.Atherosclerosis typically begins in early adolescence, and is found in most major arteries but since it is asymptomatic during the early half of life we need cardiovascualr risk markers to help assess patient risk. If an at-risk patient is identified early, the hope is that medication, lifestyle changes or medical procedures can be used to avert a serious cardiovascular event. So, although the vast majority of us have some degree of atherosclerosis, risk markers can help identify those among us who are in more imminent danger or who have increased risk of an adverse cardiovascular event. | View Page |
| Patient Studies to Validate Risk Markers Risk markers are first hypothesized and then tested. Once a potential marker is identified, concentrations of the serum marker are correlated with patient outcomes. Cardiovascular risk marker studies are typically either retrospective or prospective epidemiology studies. A retrospective study looks backwards at a patient population. For example, we identify (through a hospital database perhaps) patients who have had myocardial infarcts or some other adverse outcome as well as similar subjects without that outcome to use as controls. We then go back and find archived patient serum samples and relate the concentrations of our new risk marker with patient outcomes. Retrospective studies can only be performed if you have archived samples from the patient. Prospective studies look forward in time. For example, we first select a group of subjects and measure our new risk marker in these patients over time. After a few years, we see how the serum concentrations relate to the patient outcomes. Obviously, prospective studies take much longer to perform than retrospective studies. Whatever study model is used, when assessing the value of a cardiovascular risk marker, we must correlate serum concentrations with a specific outcome. The outcome is determined by the study authors. Outcomes could be things like myocardial infarction, stroke, a diagnosis of coronary artery disease, death, or any cardiovascular 'event.'Concentrations of risk markers are divided into tertiles, quatriles or quintiles. This simply means that the top 33%, top 25% or top 20% of the serum concentration values are compared to the bottom 33%, 25% or 20%. For example, risk marker studies will often compare the outcomes of patients with serum concentrations in the upper tertile (those in the top third) with those in the bottom tertile (those in the bottom third) to see if the top 33% had significantly worse outcomes; if so, the risk marker has clinical value. | View Page |
| Measuring Apolipoproteins Recall that the inflammatory events leading to atherosclerosis are due to the presence of LDL particles which diffuse through the endothelium and into the vessel wall. It makes sense that the more LDL particles there are, the more risk there would be for LDL depositing in the vessel wall. It would seem therefore that measuring the number of LDL particles could be more useful than measuring the cholesterol content of the particles. Traditional measurements of LDL-C quantify the amount of cholesterol associated with all the LDL in a patient sample; they don't tell us how many LDL particles there are. An analogy can be made with battleships. If you wanted to measure the size of a navy that was sailing for your shores, it makes more sense to count the number of ships than to count the amount of cargo the ships carry in order to estimate the number of ships. Of course, it is intuitive that the more LDL-C there is, the greater the number of LDL particles. In that sense, LDL particle number should correlate to LDL cholesterol, and this is indeed true. However, studies now show that measurement of the number of LDL particles is a more powerful predictor of cardiovascular risk. The exact relationship between LDL particle number and cholesterol content actually varies due to the fact that the lipoproteins vary in size and in the ratio of triglycerides to cholesterol. So, although cholesterol is related to LDL particle number, it is not in perfect proportion.How can we then measure LDL particle number? The most obvious way would be to measure apolipoprotein B100 (often abbreviated ApoB). Each LDL particle has one molecule of ApoB attached to it. Therefore, if we measured ApoB, we would be measuring the number of LDL particles, not the contents of those particles, and number appears to be more important with regard to adverse outcomes. | View Page |
| Analysis of medical errors and adverse events creates opportunities to improve healthcare systems. True or false? | View Page |
| Root Causes are specific, underlying, and identifiable reasons that ________ occur. | View Page |
| These statements define terms related to medical error prevention. | View Page |
| Root Cause Analysis considers potential improvement processes to reduce the likelihood of repeating an adverse event. True or false? | View Page |
| Which statement describes an Adverse Event? | View Page |
| Which item is a product of Failure Mode and Effect Analysis? | View Page |
| RCA Value A technologist performs a venipuncture for glucose testing on the wrong patient. This medical error leads to the patient receiving an incorrect dose of insulin and the patient goes into a coma--this medical error led to an adverse event. Analysis without RCA: Determines the technologist should have checked the patient's wristband (the immediate reaction). Questions why the technologist did not also verbally identify the patient (the subsequent reaction). Restates these reactions (in the internal follow-up review). Misses causes discoverable by a detailed and open investigation.Analysis with RCA: Includes descriptions of events leading up to a "wrong person procedure" in its reports. Describes 17 separate errors identified in the follow-up investigation. Recommends actions that should avoid reoccurrence of the error. | View Page |
| RCA Considerations RCA considers the following elements: Factors associated with an adverse event Study of specific processes related to the event Potential improvement processes to reduce the likelihood of repeating the event Questioning that probes deeply by repeatedly asking "Why?" Analysis that is thorough and credible | View Page |
| Sentinel Events The Joint Commission calls adverse events Sentinel Events. It defines a Sentinel Event as an unexpected occurrence that involves death or serious physical or psychological injury, or the risk that these might occur. RCA analyzes Sentinel Events. | View Page |
| The Joint Commission and Sentinel Events The Joint Commission learns about 80% of known Sentinel Events through healthcare organization reports and 20% through information from other sources, such as the media. In 1996, The Joint Commission implemented a "Sentinel Events Policy" for healthcare organizations. This policy requires organizations to monitor and report adverse events, explore their causes, and report on changes they make in response to the event. | View Page |
| The Joint Commission Sentinel Event Alert Since 1998, the Joint Commission has issued 25 Sentinel Event Alerts to the healthcare community. These publications include more than 50 evidence or expert-based recommendations for preventing adverse events. Sentinel Event Alerts address various error reduction topics: Transfusion reactions Inpatient suicide Infant abductions Wrong site surgery or other procedures Patient fallsLaboratory professionals can be involved in all of these types of Sentinel Events. The Joint Commission's first Sentinel Event Alert addressed the common practice of storing concentrated potassium chloride solutions in hospital nursing units. | View Page |
| Sentinel Events Review | View Page |
| Analyzing Medical Events You can use your understanding of medical errors, adverse events, and near misses to examine medical situations that have unexpected, negative outcomes.
You analyze these situations by asking several questions: What happened before, during, and after the situation?Who and what factors and circumstances are involved?Were established standard practices followed?Did a medical error or errors lead to this situation? | View Page |
| Root Cause Analysis Root causes are specific reasons that contribute to medical errors. They cause mistakes that lead to great patient harm (adverse events). Usually they can be identified. Examples: Using a wrong calculation factor Neglecting to use directions for complicated tests Reporting the wrong test result Using outdated reagents Testing clotted or partially-filled samples Diluting a test sample incorrectlyIn most cases, management has the authority and means to resolve root causes. Root Cause Analysis also recommends actions to prevent reoccurrence of an adverse event. | View Page |
| Steps in Root Cause Analysis | View Page |
| Root Cause Analysis Reports Root cause analysis (RCA) reports avoid declaring that errors are caused by preconceived notions or the first mistakes identified. By definition, RCA emphasizes analysis of situations. Its most important products are detailed reports that describe the sequence of events that lead to adverse events. | View Page |
| Discussion Laboratory discussion meetings help to prevent medical errors. The staff can meet periodically to discuss recent averted adverse events and ones that might have been averted.Discussion should not be about blame. Privacy must be protected, so real names should not be identified. Management can provide guidelines for discussion and analysis.A suggested format for discussion:1. Briefly describe each adverse event.2. Identify its possible causes.3. Discuss relevant guidelines.4. Suggest possible preventive actions.Discussion can include actions that do and do not work to prevent medical errors. | View Page |
| American Society for Clinical Laboratory ScienceThe American Society for Clinical Laboratory Science, ASCLS, joins the leadership effort to prevent medical errors and increase patient safety. | View Page |
| Near Misses Near misses are also related to medical errors: Near misses are medical events that avert unwanted consequences.Someone or something identifies and corrects harmful influences before they cause adverse events.The medical community sometimes calls near misses “close calls.”
For example, a transfusion is stopped when the nurse discovers that the identification number on a unit of blood does not match the unit number on the requisition. This is a near miss for the patient receiving a transfusion of incompatible blood.
Near misses often provide important insight into new ways of preventing medical errors. In this case, a flaw in Blood Bank cross-checking systems is discovered so it can be prevented from causing a medical error. | View Page |
| Medical Negligence Unfortunately, adverse events do occur in healthcare situations. They may or may not be preventable and they may or may not involve medical negligence. Medical negligence is a legal term. It describes adverse events involving patient care that fails to meet specific, established standards. Medical negligence occurs when a medical professional does not perform the correct action, resulting in great patient harm (an adverse event). | View Page |
| Adverse Events Medical errors lead to adverse events--unintended injuries or other negative health consequences. These unfortunate events are caused by medical mismanagement, not underlying patient diseases or conditions.
Adverse events may or may not be preventable.
| View Page |
| Preventable and Unpreventable Adverse Events Adverse events due to medical errors are usually preventable. Adverse events due to uncontrollable factors are typically not preventable. | View Page |
| Bleeding After a Venipuncture Can Be an Adverse Event Excessive bleeding after a venipuncture can occur as a preventable or an unpreventable adverse event. Laboratory professionals might or might not have control over this situation because of the factors involved. For example:
Bleeding due to failure to apply immediately pressure on the venipuncture site is a preventable adverse event. Bleeding due to later injury to the venipuncture site is an unpreventable event. Circumstances that cause the bleeding determine whether it is a preventable or unpreventable adverse event. | View Page |