Beneficial effects of buprenorphine (a partial opiate agonist) in porcine Escherichia coli septicaemia: a comparison with naloxone.

The cardiovascular and metabolic responses to treatment with naloxone or buprenorphine (a partial opiate agonist) were investigated in a porcine model of septicaemia. Animals anaesthetised with alpha-chloralose were infused with live E. coli over two hours. They were then divided into three groups and received either naloxone (2 mg kg-1 + 1.5 mg kg-1 hr-1) or buprenorphine (0.3 mg kg-1) or an equivalent volume of normal saline. Treatment was started one hour after commencing the infusion, by which time a significant fall in cardiac index (CI), stroke index (SI), mean arterial pressure (MAP), and pH had occurred in all groups, together with a significant rise in mixed venous blood lactate and packed cell volume. Treatment with both naloxone and buprenorphine resulted in significant improvements in CI, pH, and base excess and in a fall in mixed venous lactate and packed cell volume. Although no significant effect on survival was seen at three hours after the start of treatment, buprenorphine may prove to be a suitable alternative to naloxone in the management of septic shock.