Cardiopulmonary effects of intravenous fluid overload: radiologic manifestations.

Large volumes of normal saline were infused intravenously in 6 dogs until obvious pulmonary edema was observed radiographically. Following volume overload, statistically significant increases occurred in the size of the heart, left atrium, pulmonary arteries and veins, and systemic veins, without the development of congestive heart failure (CHF). The left ventricular end-diastolic pressure remained normal, and cardiac output and stroke volume increased. The results suggest that, in the absence of left ventricular failure, acute volume overload may simulate the radiographic changes produced by CHF. Pulmonary edema may have occurred at least partly from a marked decrease in serum colloid osmotic pressure.