critical care medicine
How To Do Venous Blood Sampling
Relevant Anatomy for Venous Blood Sampling
The median cubital and cephalic veins are preferred for blood sampling, but other arm and hand veins may be used. The cephalic vein is located on the lateral (radial) side of the arm, and the basilic vein is located on the medial (ulnar) side. These veins extend through and branch within the antecubital fossa, creating the large antecubital and proximal forearm veins. The brachial artery (blood supply to the forearm and hand) lies deep to the basilic vein in the upper arm and bifurcates into the radial and ulnar arteries in the antecubital fossa or proximal forearm. Caution must be taken to avoid arterial puncture. Leg veins (eg, dorsal digital veins and the greater saphenous vein inferoanterior to the medial malleolus) or external jugular veins may be used if upper extremity veins are inaccessible. 