Venipuncture Using a Syringe

• Use a syringe when the patient's veins are small or fragile because suction from an evacuated tube can cause the vein to collapse. Using a syringe allows control of the amount of suction.
• Steps for venipuncture are the same as the evacuated tube system.
• Once in the vein, pull back on plunger to obtain desired amount of blood. Release tourniquet and withdraw needle while applying a folded gauze 2 × 2 and pressure to venipuncture site.
• Transfer blood to appropriate tubes by first replacing needle with large-bore (18 gauge) needle (prevents hemolysis).
• Insert needle into the stopper and allow tube to fill by vacuum.
• Follow the correct order of tube top color.