Dexmedetomidine versus morphine infusion following laparoscopic bariatric surgery: effect on supplemental narcotic requirement during the first 24 h.

INTRODUCTION: The primary aim of this pilot study was to determine whether the dexmedetomidine infusion initiated immediately after laparoscopic bariatric surgery, offers an advantage over a morphine infusion with respect to rescue morphine and paracetamol requirements over the first 24 post-operative hours. METHODS: Sixty morbidly obese adult patients scheduled for laparoscopic bariatric surgery were randomly assigned to receive an infusion of either 0.3 mcg/kg/h dexmedetomidine (Group D) or 3 mg/h Morphine (Group M) for 24 h immediately post-operatively. All patients received standardized general anesthesia and were evaluated and treated for pain in the intensive care unit by providers who were blinded to their treatment group. The primary outcome was the need for supplemental, "rescue" paracetamol (Dolargan. Hikma, Jordan) and morphine titrated to achieve visual analog scales (VAS) of <40 and <70, respectively. RESULTS: A total of 60 patients (77 % female, mean age 33.5 years ± 9.5 and body mass index (BMI) 43.0 ± 4.5) were randomized to Group M and 30 to Group D. There were no significant differences in mean rescue paracetamol and morphine requirements. Mean total morphine requirements in Group D were 6.1 ± 3.1 mg, whereas 72.9 ± 2.2 mg in Group M (p < 0.0001). CONCLUSIONS: An intravenous infusion of dexmedetomidine, initiated and continued for 24 h following laparoscopic bariatric surgery, can decrease the overall morphine requirements during this period. This pilot study demonstrated that the post-operative initiation of dexmedetomidine can be morphine sparing following laparoscopic bariatric surgery.

The impact of long-lasting preemptive epidural analgesia before total hip replacement on the hormonal stress response. A prospective, randomized, double-blind study.

UNLABELLED: Recent studies suggest that preemptive analgesia may be effective in reducing postoperative pain. One physiologic explanation may be interference with the endogenous opioid response. We investigated whether long-lasting preoperative preemptive analgesia may have an effect on the hormonal stress response after total hip replacement. METHODS: 42 patients scheduled for elective hip replacement for coxarthrosis were randomized to receive, on the day before the operation, either 5 ml*h(-1) ropivacaine 0.2% (study group, n = 21) or 5 ml*h(-1) saline (control group, n = 21). Postoperative analgesia was achieved in both groups by patient-controlled epidural analgesia (PCEA) with ropivacaine 0.2%. The main outcome measure was the concentration of authentic beta-endorphin [1-31] in plasma up to 4 days after surgery. Additional parameters included concentrations of adrenocorticotrope hormone and cortisol. RESULTS: Both groups were comparable concerning preoperative parameters and pain scores. Epidural blocks were sufficient in all patients for operative analgesia. Preemptive analgesia was performed for 11-20 hours in both groups and led to significantly decreased pain scores before surgery. Preemptive analgesia with epidural ropivacaine did not lead to decreased concentrations of beta-endorphin [1-31] before the start of surgery or in the postoperative period. Furthermore, no differences could be detected in the time course of beta-endorphin and adrenocorticotrope hormone after surgery. However, cortisol concentrations differed significantly between groups before the operation, but showed a comparable rise after surgery. CONCLUSION: Differences in postoperative pain after preemptive analgesia do not seem to be due to an altered endogenous opioid response.