The Effect of Intraoperative Dexmedetomidine Versus Morphine on Postoperative Morphine Requirements After Laparoscopic Bariatric Surgery.

Background: Dexmedetomidine is an α receptor agonist with sedative and analgesic properties. During bariatric surgery, its use may reduce postoperative opioid requirements, reduce their side effects, and improve quality of recovery. The aim of this prospective randomized controlled trial was to compare the effect of dexmedetomidine bolus and infusion versus morphine bolus given prior to the end of laparoscopic bariatric surgery.

Methods: Sixty morbidly obese patients (BMI > 40 kg m) aged 18 to 60 years, undergoing laparoscopic sleeve gastrectomy, received morphine sulfate (bolus 0.08 mg kg followed by a saline infusion) (group M, n = 30) or dexmedetomidine (loading dose of 1 μg kg followed by 0.5 μg kg h) (group D, n = 30) 30 min before the end of surgery. Data collected included morphine consumption in the post-anesthesia care unit (PACU) (primary outcome) and at 24 h, pain intensity, nausea, heart rate, blood pressure, vomiting, sedation, and quality of recovery.

Results: There was no significant difference in morphine consumption in the PACU (group D 12.2 ± 5.44 mg, group M 13.28 ± 6.64 mg, P = 0.54) or at 24 h (group D 40.67 ± 24.78 mg, group M 43.28 ± 27.79 mg, P = 0.75); when accounting for intraoperative morphine given group M had significantly higher morphine consumption when compared to group D (23.48 ± 6.22 mg vs. 12.22 ± 5.54 mg, respectively, P < 0.01). Group D patients had more cardiovascular stability.

Conclusions: Dexmedetomidine given prior to end of laparoscopic sleeve gastrectomy provides the same level of postoperative analgesia as morphine with better hemodynamic profile.