Detecting and minimizing pre-analytical variables in clinical analysis
Read more: Pre-Analytical Errors in Biomedical ChemistryLaboratory
Pre-analytical variables refers to any and all procedures that occur during sample collection, prior to sample analysis. This involves patient identification, physical sample collection, sample transportation to the testing site and sample preparation.
Pre-analytical errors account for 32%-75% of laboratory errors1. These errors can have a significant impact on laboratory results and it is imperative that laboratory personnel are able to spot these erroneous results, rather than falsely attributing them to an underlying medical cause.
External pre-analytical variables
Some factors such as exercise, eating, drinking and medication can affect patient results. Eating and drinking affects glucose, triglycerides, alkaline phosphatase, alanine, aminotransferase, inorganic phosphate, cholesterol, folic acid, urea, potassium and more. It is recommended that a fasting sample be taken if these sensitive parameters are to be measured.
Exercise should not be undertaken immediately before blood tests such as CK, AST and LDH. In some cases, medication may be postponed for several days until a blood test can be taken, unless the blood test is for therapeutic drug monitoring purposes.
Read more: Pre-Analytical Errors in Biomedical ChemistryLaboratory