Cortisol, Glucose, and Hemodynamic Responses to Surgery after Naloxone Administration

Abstract

The adrenocortical, hyperglycemia and hemodynamic responses to cholecystectomy or vagotomy were studied in 16 patients under halothane and N2O/O2 anesthesia. The patients were randomly divided into 2 groups: 8 patients received naloxone in doses used clinically (2.5 .mu.g/kg i.v.) just before induction of anesthesia, while 8 subjects received placebo. Insignificant differences were shown in plasma concentrations of cortisol and glucose between groups. Nor did blood pressure, heart rates and inspired halothane concentrations differ significantly between groups. Inhibition of opiate receptors and endorphins by naloxone in an otherwise clinically effective dosage does not influence the adrenocortical, hyperglycemic or hemodynamic responses to surgical stress. Opiate receptors and endorphins are not involved in the initial phase of the endocrine-metabolic responses to surgery nor are they part of the neural mechanisms mediating stress-induced analgesia.