Which of the following is a cardiovascular consequence of immobility?

• A. Orthostatic hypotension
• B. Deep vein thrombosis
• C. Venous stasis
• D. Decreased cardiac output

Answer: (A)

Immobility disrupts how the cardiovascular system maintains blood pressure when moving to an upright position. With prolonged bed rest, venous return to the heart is reduced because the calf muscle pump isn’t helping push blood back up, and circulating volume can decrease. The autonomic reflexes that normally counteract pooling and hold blood pressure up become blunted. When the person stands, there isn’t enough compensate, so blood pressure drops—orthostatic hypotension. This reflects the dynamic regulation of blood pressure with posture after a period of inactivity and is the cardiovascular change most directly tied to immobility.

Venous stasis and deep vein thrombosis are important risks of immobility caused by stagnant blood in the legs, but they’re vascular issues rather than the immediate postural blood-pressure problem. Decreased cardiac output can occur with deconditioning, but the standing BP drop is the clearer, more specific cardiovascular consequence of immobility.