Final answer:
When the antecubital fossa is not available for venipuncture, other sites include the median antebrachial vein, the cephalic vein, the basilic vein, and the back of the hand. For more central access, the subclavian or internal thoracic veins may be used.
Step-by-step explanation:
If the antecubital fossa is not available for a blood draw, other locations can be considered. Alternative veins include the median antebrachial vein, which parallels the ulnar vein and joins the basilic vein in the forearm. Additionally, the cephalic vein can be used; it begins in the antebrachium and is easily visible in many individuals running along the biceps brachii muscle. The basilic vein continues through the arm to become the axillary vein, which is another possible site. The back of the hand and the dorsal venous network also present alternative locations for venipuncture. In certain cases, when a peripheral site cannot be found, more central veins such as the subclavian or internal thoracic veins may be considered by a medical professional.