ABSTRACT. We studied the effects of a single dose ofStudies in adults with pulmonary edema (5-7) have shown intravenous furosemide on the body water compartments variable effects of furosemide on plasma volume. Davidor et al.of nine infants with bronchopulmonary dysplasia. We (5) measured plasma vol in patients with refractory edema 2 h measured total body water, extracellular water, and plasma after an intravenous dose of furosemide. These patients had a volume using deuterium oxide, sodium bromide, and Evans mean decrease of 25% in plasma volume. Figueros and Weil(6) blue dye, respectively. From the results of these measure-found that the plasma volume of adults with acute cardiogenic ments, we calculated cell water, interstitial water, red cell pulmonary edema was lower than normal before therapy but volume, and total blood volume. We performed these meas-rose after treatment with furosemide, oxygen, and morphine.urements on the first day of the study and again 28 h later, Schuster et al. (7) measured blood volume in 2 1 patients with 4 h after an intravenous dose of furosemide (1 mglkg). All pulmonary edema who had either normal or decreased renal infants had a brisk diuresis in the first hour after the dose, function. The patients who had normal renal function, as indibut urine output was no greater during the 24-h period cated by a good diuresis, had no change in plasma volume 4 to after the dose than during the preceding 24-h period. Total 6 h after a single intravenous dose of furosemide. Patients who body water, extracellular water, and interstitial water were did not have a good diuresis had a rise in plasma volume. significantly decreased 4 h after furosemide. There was no There have been no similar studies in infants. Infants with change in plasma volume, red cell volume, or total blood BPD are often fluid restricted with the hope that this will reduce volume (Pediatr Res 26: 121-124, 1989) pulmonary edema. It would be of practical value to know whether furosemide causes a decrease in plasma volume in these Abbreviations infants, because hypovolumeemia might compromise organ perfusion and activate the compensatory mechanisms that stimulate BPD, bronchopulmonary dysplasia water and sodium retention. Our study was undertaken to assess TBW, total body water the effects of a single intravenous dose of furosemide on the IW, interstitial water plasma volume and other body water compartments of infants ECW, extracellular water with BPD. PV, plasma volume CBS, corrected bromide space Br, bromide MATERIALS AND METHODS