Vasopressin vs norepinephrine in endotoxic shock: systemic, renal, and splanchnic hemodynamic and oxygen transport effects.

Abstract

The effects of intravenous norepinephrine (NE, group 1) and vasopressin (AVP, group 2) infusions on systemic, splanchnic, and renal circulations were studied in anesthetized dogs under basal conditions and during endotoxic shock. Under basal conditions, AVP infusion induced a 12 +/- 7% drop in left ventricular stroke work, a 45 +/- 5% fall in portal venous blood flow, and a 31 +/- 13% decrease in intestinal mucosal blood flow (P < 0.05). AVP also decreased splanchnic oxygen delivery (Do2) and increased splanchnic and renal oxygen extraction significantly during basal conditions. Except for more pronounced brady-cardia among animals in group 2, the systemic and splanchnic changes were comparable between study groups during endotoxic shock. AVP infusion restored renal blood flow and Do2 in endotoxic shock compared with animals resuscitated with NE, which had persistently low renal blood flow and Do2. Our data demonstrate that, in contrast to NE, administration of AVP effectively restores renal blood flow and Do2 with comparable systemic and splanchnic hemodynamic and metabolic effects in endotoxin-induced circulatory shock.