EFFECTS OF NITRIC-OXIDE SYNTHASE INHIBITION ON REGIONAL BLOOD-FLOW INA PORCINE MODEL OF ENDOTOXIC-SHOCK

The results of early studies suggest that nitric oxide (NO) synthesis inhibition may be therapeutic in sepsis, but recent data indicate that NO inhibition may be harmful, This study investigates the effects of NO synthesis inhibition with N-nitro-L-arginine methyl ester (NAME) on regional blood flow following endotoxemia, Anesthetized, instrumented swine were randomly divided into four groups, Controls received norma l saline resuscitation (NSR) at 1 cc/kg/min beginning at T-0. The lipo polysaccharide group (LPS) received NSR and Escherichia coli LPS, 200 mu g/kg at T-0, The LPS + NAME group received NSR and LPS at T-0, plus NAME (50 mu g/kg/min) starting at T-1, The NAME group received only N SR and NAME, Hemodynamic data, regional blood flow, and gastric intram ucosal pH (pH(i)) were measured hourly, LPS increased renal and caroti d blood flow consistent with a hyperdynamic state, Mesenteric blood fl ow was decreased, Treatment of endotoxic animals with NAME decreased r enal and carotid blood flow, Mesenteric blood flow and gastric pH(i) w ere improved by NAME. NO inhibition in endotoxic shock results in decr eased carotid and renal blood flow, by decreasing cardiac output, Mese nteric blood flow and perfusion were improved; however, this requires further study for validation.