Depth of anesthesia with desflurane does not influence the endocrine-metabolic response to pelvic surgery

Background: It has been reported that, with deep levels of anesthesia achieved with general anesthetic agents and opioids, post-operative consumption of morphine and pain intensity can be reduced. It is not clear whether the depth of anesthesia modifies pain intensity by influencing the endocrine-metabolic stress response. The purpose of this study was to assess the influence of a high concentration of desflurane on peri-operative plasma cortisol. Methods: The study was prospective and observer blinded, and included 20 women scheduled for elective total abdominal hysterectomy. They were randomly divided in to two groups: a deep group (D) (n=10) and a light group (L) (n=10). Anesthesia was induced with propofol, fentanyl and rocuronium: desflurane was administered at two different concentrations according to Bispectral Index monitoring (deep, 25 and light, 50). Post-operative pain relief was achieved with patient-controlled analgesia (PCA) with intravenous morphine. Blood samples were taken before, during and after surgery for the measurement of plasma cortisol, glucose and lactate. Post-operative pain visual analog scale (VAS) and morphine consumption were recorded at regular intervals for the first 24 h. Results: The Concentrations of plasma cortisol, glucose and lactate increased with surgery in both groups, and remained elevated, with no difference between the two groups. VAS and morphine consumptions were similar in both groups. Conclusion: The results show that there is no relationship between the intra-operative level of anesthesia depth achieved with desflurane and the extent of endocrine-metabolic stress response.