Applying a tourniquet
If you ve chosen a ven in the hand or lower arm, apply the tourniquet 2 to 3 inches (5 to 75 cm) below the ante- cubital fosca. (With an obese patient, place it a few inches lower for better capillary filling. To apply it as pain- lessly as possible, avoid pulling hair or pinching the skin. Fun it tight enough to trap venous blood in lower arm capillaries and veins with- out cutting off arterial fiow. If you can't feel a pulse below the tourni- quet (or if the patient complains of discomfort), it's too tight. As the occluded veins distend, the skin below the tourniquet will become darker from venous congestion disposable tourni- Single-patient-use quets are preferred because reusable tourniquets can be a source of cross- contamination. If not discarded, tourniquets should be cleaned after each use Be aware that tourniquets are also a a source of latex contact, so assess for allergies.
1. Make sure the tourniquet lies flat against the patient's skin. Bring the ends of the tourniquet toward each other, so that one overlaps the other
2. To tie the tourniquet, lift and stretch it, then use two fingers to tuck the top tail under the bottom, as shown. Make sure the tails point away from the venipuncture site.
3. Use this technique to stabilize the veins: Lift the tied tourniquet and stretch the skin and underlying tissues away from the venipuncture site, as shown here. Then gently lower the tourniquet. You may be able to retract several inches of skin and tissue away from the site with this maneuver, which is especially helpful with older patients (who have less collagen and elastin than younger patients) and patients