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Collecting Blood Specimens

First thing to do before greeting Mr. Jack Smith is to wash my hands, wear gloves, and prepare my equipment tray. Then I will ask him to give me his full name and birth date to confirm his identity. When confirmed, I will explain the procedure, ask if he has any allergies, and warn him that the needle may hurt when penetrating the flesh. After his approval, I will ask him to sit in a chair to avoid falling if fainting occurs during the procedure.

I will first start with the CBC (Complete Blood Count), as it is one of the tests that have to be done in the beginning (alongside the coagulation tests). CBC is a quantitative and qualitative analysis of red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes). The blood is drawn in a tube containing an anticoagulant substance, using a Venipuncture. The most common sites for this procedure are in the antecubital fossa and forearm. Before collecting the blood specimen, I will disinfect the puncture site, place the tourniquet 3 to 4 inches above the patient’s elbow, insert the needle just enough to penetrate the vein, and draw 3 to 4.5ml of blood. At this time, I can proceed with the PT test (Pothrimbin Time) that measures the times it takes for a plasma specimen to clot; I will pull off the small vial, and plug in a new one to collect a second sample for the PT test; then I will remove the tourniquet, put an alcohol swab on the site, and ask the patient to retract his forearm.

Knowing that Mr. Jack Smith has not had anything to eat in 12 hours, I can perform the fasting glucose and electrolytes test as well. The fasting glucose test determines the amount of glucose in a blood, and the electrolytes test is used to detect an electrolyte imbalance. First I will clean the last phalange of a finger with an alcohol swab, put the lancet perpendicularly on the finger to puncture the site. After whipping the first blood of blood, I will use two micropipettes, one after the other, to collect blood samples for each of the two tests, and insert them on the sealant. Finally, I will clean the site with alcohol, check for bleeding, and apply a band aid.