The Packed Cell Volume (PCV) Test 1. Objective: This is one of the oldest tests done in medical practice. The objective of this test was to determine the percentage of red blood cells (RBCs) in whole blood. It also helped to assess the blood’s capacity to carry oxygen. ________________________________________ 2. Principle: The test was based on the principle that when blood was centrifuged, the red blood cells settled at the bottom of the tube, forming a packed column. The ratio of the packed RBC column to the total blood column gave the packed cell volume (PCV), expressed as a percentage. ________________________________________ 3. Materials: • Microhematocrit capillary tubes • Microhematocrit centrifuge • Plasticine or sealing clay • Microhematocrit reader • Lancet • Alcohol swab • Cotton ________________________________________ 4. Procedure (Microhematocrit Method): 1. The fingertip was cleaned with an alcohol swab and pricked with a sterile lancet. 2. Blood was collected into ...
WHAT HAPPENS WHEN YOU RECEIVE BLOOD FROM AN INCOMPATIBLE DONOR? If you receive blood that is not compatible with your blood, your body produces antibodies to destroy the donor's blood cells. This process causes the "transfusion reaction" [AKA ABO incompatibility reaction]. Blood that you receive in a transfusion must be compatible with your own blood. WHAT IS AN ABO INCOMPATIBILITY REACTION? An ABO incompatibility reaction can occur if you receive the wrong type of blood during a blood transfusion. It is a rare but serious and potentially fatal response to incompatible blood by your immune system. The four main blood types are A,B, AB,and O. If you are type A, your red blood cells have proteins attached to them known as A antigens.Type B blood cells carry B antigens.Type AB blood has both A and B antigens,and type O blood has neither A nor B antigens. Your immune system will produce antibodies against any blood antigens you don't have in your own blood. That means peo...