I recently received a lab report that indicated a specimen was "hemolyzed." What does that mean and what caused that to happen?
Hemolysis refers to the destruction of red blood cells which leads to the release of haemoglobin from within the cells. Hemolysis affects specimen quality and, consequently, can affect the results for certain laboratory tests. Site personnel can prevent hemolysis by avoiding the circumstances that can cause it. These include:
Too great a vacuum in the vein, causing the red cells to be drawn toward the bore of the needle too quickly. Also the red cells could be forced through too small an opening too quickly. Using too large a vacutainer tube on too small a vein.m Too slow a flow of blood into the tube, indicating that the flow is somehow obstructed (such as the opening of the needle being too close to the upper or lower lumen wall). Using too small a gauge needle for the vacuum applied to the blood collection system (be it variable by syringe or constant by vacuum draw system). Too large a gauge needle resulting in too great a vacuum pulling too much blood through the opening too quickly. Vigorous mixing or shaking of the filled collection tube. Not mixing an anticoagulated sample after it has been collected. Centrifuging an anticoagulated blood sample to check for hemolysis.
The lavender-top tubes that I sent to your laboratories could not be processed because the specimen clotted. How did this happen? What can be done to prevent clotting?
Specimen clotting usually occurs because the collected blood does not mix thoroughly with the EDTA preservative that is contained in the tube. To avoid this problem collect the specimen, then invert the tube 8-10 times at approximately a 180° angle (the equivalent of a semi-circle). This procedure will permit the EDTA to thoroughly mix with the specimen so that clotting does not occur. Also, do NOT store this type of sample at a refrigerated or frozen temperature prior to shipping. Your ICON Laboratories Investigator Manual provides step-by-step, illustrated instructions that should also be helpful in properly preparing this specimen.
Why do I have to prepare Peripheral Blood Film slides when sending a CBC with Differential to the lab? How do I properly prepare the slides?
Preparing and sending a quality Peripheral Blood Film is a critical procedure to ensure that accurate test results are reported for your study subject. When the specimen you collect for the a CBC with Differential arrives at our laboratory , the testing is performed on an automated instrument. If the instrument detects an abnormality, or requires confirmation, a laboratory technologist will perform what is known as a "manual differential." To ensure that the specimen abnormalities are not due to specimen transport issues or time delays, the laboratory relies upon slides made from freshly collected blood, prepared at the investigator site at the time of specimen collection. Since proper preparation of the Peripheral Blood Film slide is so important, we have provided a brief video that demonstrates the proper preparation procedures. View Video Here.
Does it matter how I place the bar code label on the collection tube?
YES! The bar code is the primary means of tracking the sample at our lab from the time of receipt through testing and storage. To ensure that it can be scanned appropriately the bar code should ALWAYS be affixed so that it is aligned with the tube (The bar code should not go around the tube.) It is also important that the label not cover the tube cap. Proper labeling facilitates scanning and prevents delays in reporting. Also, please remember to affix a bar code label in the designated place on each copy of the requisition to properly link the requisition to the samples submitted for that visit.