How to collect venous blood

This video demonstrates the standard clinical procedure for venous blood collection (phlebotomy). The process emphasizes patient comfort and the prevention of hemolysis—the rupture of red blood cells—which can invalidate test results.

Key steps of the procedure include:

Patient Comfort: The process begins by ensuring the patient is sitting comfortably (0:00-0:07).
Site Preparation: The phlebotomist selects an appropriate vein and applies a tourniquet approximately three inches above the puncture site (0:09-0:32). The site is then cleaned using a circular motion to disinfect the area (0:42-1:02).
Venipuncture: After checking the needle, the phlebotomist anchors the skin and inserts the needle into the vein (1:20-1:47).
Sample Collection & Handling: Careful collection is critical; if the needle is improperly positioned or if the blood hits the piston with too much force, the red blood cells may rupture (hemolysis), rendering the sample unusable (2:13-2:18). After the blood is collected, the tube is gently mixed to ensure the specimen is properly prepared for the laboratory (2:50-3:00).
Proper technique, such as avoiding excessive force during collection and gentle mixing of the sample, is essential to maintain specimen integrity.