Arginine vasopressin does not alter mucosal tissue oxygen tension and oxygen supply in an acute endotoxemic pig model

Objective To determine the effects of increasing dosages of continuously infused arginine-vasopressin (AVP) on mucosal tissue oxygen tension and oxygen supply in an auto-perfused, innervated jejunal segment in an acute endotoxic porcine model.Design Prospective, randomized, experimental study.Setting University hospital animal research laboratory.Interventions Jejunal mucosal tissue PO₂ was measured employing two Clark-type surface oxygen electrodes. Oxygen saturation of jejunal microvascular hemoglobin was determined by tissue reflectance spectrophotometry. Systemic hemodynamic variables, mesenteric-venous and systemic acid base and blood gas variables and lactate measurements were recorded. Measurements were performed at baseline, after E. coli lipopolysaccharide (LPS) administration and at 20 min intervals during incremental AVP infusion ( n =8; 0.014, 0.029, 0.057, 0.114 and 0.229 IU kg^-1 h^-1, respectively) or infusion of saline ( n =8).Measurements and results LPS infusion leads to a significant ( P <0.05) decrease of mucosal tissue oxygen tension (PO₂muc, 24±3 to 12±2 mmHg) and microvascular hemoglobin oxygen saturation (HbO₂, 38±4 to 21±4%). Mesenteric venous lactate level increased (2.4±0.3 to 4.7±1.7 mmol l^-1), while mesenteric venous pH decreased (7.38±0.02 to 7.26±0.12), indicating tissue hypoxia. AVP significantly increased mean arterial pressure (MAP, 81±15 to 97±17 at 0.057 IU kg^-1 h^-1). No differences in jejunal mucosal oxygenation occurred between study groups at any dosage during the experimental protocol.Conclusion AVP administration did not further compromise mucosal tissue oxygen tension and oxygen supply in the acute phase of endotoxic pigs.This article refers to the editorial