Pentobarbital improves nitrogen retention in sepsis

Pentobarbital therapy has been associated with decreased urinary nitrogen excretion and resting energy expenditure in stressed patients. The metabolic effects of pentobarbital in sepsis were investigated in 29 well-nourished rats who underwent superior vena caval cannulation, cecal ligation, and puncture. Animals were randomly assigned to receive either a continuous infusion of 20 mg/kg/day of pentobarbital combined with parenteral nutrition (n = 13) or parenteral nutrition alone (n = 16). Both groups received isocaloric, isonitrogenous parenteral nutrition postoperatively for 24 hr. Mean nitrogen balance (± SEM) was better in the pentobarbital group (+169 ± 76 mg/kg/day vs -190 ± 66 mg/kg/day, p < 0.01). No significant differences between the pentobarbital and control groups were noted for urinary 3-methylhistidine excretion (9 ± 0.7 μg/kg/day vs 11 ± 0.6 μg/kg/day, respectively) or 24 hr survival (77% vs 69%, respectively). Pentobarbital improves nitrogen retention without decreasing urinary 3-methylhistidine excretion in septic rats.