Clinical and experimental studies indicate that intravenous infusion of small volumes of hypertonic saline may be beneficial in the treatment of acute hypovolemia. After infusion, cardiac output is increased and systemic vascular resistance is lowered. The effect is transient, however, but can be prolonged by adding a colloid solution. Infusion of small volumes of hypertonic saline (7.5% NaCl) does not significantly influence serum osmolality or serum sodium concentration.