Peripheral Veins: Location, Visibility, and Function

Peripheral veins are superficial veins located close to the skin surface, visible and palpable.

Anatomy

• Upper extremity: Cephalic, basilic, median cubital, dorsal hand veins.
• Lower extremity: Great saphenous, small saphenous, dorsal foot veins.

Characteristics

• Thin walls, large lumens, valves prevent backflow.
• Appear blue/green due to light scattering (not deoxygenated blood color).
• Collapsible; distend with volume/dependency.

Function

• Return deoxygenated blood to heart (capacitance vessels — hold ~60% blood volume).
• Thermoregulation: cutaneous vasodilation/constriction.
• Clinical access: venipuncture, IV cannulation, PICC lines, dialysis fistulas (arterialized).

Clinical Relevance

• Varicose veins: valve failure → reflux, dilation.
• Thrombophlebitis: inflammation + clot.
• Chronic venous insufficiency: edema, skin changes, ulcers.

Peripheral veins are essential for circulation and clinical access.