Renal hemodynamic response to furosemide in septic and injured patients

Furosemide frequently is advocated as a prophylaxis against renal failure in septic and injured patients; this effect is thought to be secondary to an increase in renal blood flow. This postulate was tested within 72 hours of admission in 22 previously healthy patients with acute pancreatitis (two), massive trauma (ten), or severe sepsis (ten). Renal clearances of inulin (GFR), para-amino hippurate (ERPF), sodium (CNA), osmoles (COsm), and free water (CH2O) were measured in milliliters per minute before and after the intravenous infusion of furosemide (0.5 mg. per kilogram of body weight). Renal vein PAH levels (EPAH) in eight patients were used to calculate true renal plasma flow (TRPF), true renal blood flow (TRBF), and renal vascular resistance (RVR). Furosemide caused a significant increase in urine volume, CNa, and COsm; there were no significant changes in GFR, ERPF, RVR, TRBF, and EPAH. These findings also were observed when the patients were subgrouped according to elevated, normal, or low renal plasma flow and elevated renal vascular resistance. No significant changes were seen in EPAH, thus making a redistribution of renal blood flow unlikely. These studies indicate that furosemide has only a diuretic effect and no hemodynamic effect in the kidney; it has the potential of seriously reducing the circulatory volume and causing renal failure in critical patients.