Postoperative nausea and vomiting after bariatric surgery and dexmedetomidine anesthetic: a propensity-weighted analysis.

BACKGROUND

Patients undergoing laparoscopic bariatric surgery have high rates of postoperative nausea and vomiting (PONV). Dexmedetomidine based anesthetic could reduce PONV rates.

OBJECTIVES

To determine if PONV rates differ in patients undergoing laparoscopic bariatric surgery with anesthesia primarily based on dexmedetomidine or standard anesthetic management with inhalational agents and opioids.

SETTING

University hospital.

METHODS

From January 2014 to April 2018, 487 patients underwent laparoscopic bariatric surgery and met inclusion criteria (dexmedetomidine, n = 174 and standard anesthetic, n = 313 patients). In both groups, patients received preoperative PONV prophylaxis. We analyzed rates of PONV and moderate-to-deep sedation. A propensity score was calculated and outcomes were assessed using generalized estimating equations with inverse probability of treatment weighting.

RESULTS

Perioperative opioids and volatile anesthetics were reduced in dexmedetomidine patients. During anesthesia recovery the incidence of PONV was similar between dexmedetomidine and standard anesthetic patients (n = 37 [21.3%] versus n = 61 [19.5%], respectively; inverse probability of treatment weighting odds ratio = 1.35; 95% confidence interval .78-2.32, P = .281), and the incidence of sedation higher in dexmedetomidine patients (n = 86 [49.4%] versus n = 75 [24.0%]; inverse probability of treatment weighting odds ratio = 2.43; 95% confidence interval 1.47-4.03, P < 0.001). Rates of PONV and sedation were similar during the remainder of the hospital stay. A secondary sensitivity analysis was performed limited to dexmedetomidine patients who did not receive volatile and results were similar.

CONCLUSIONS

While dexmedetomidine-based anesthesia was associated with reduced opioid and volatile agents use, it was not associated with a reduction of PONV. The higher rates of moderate-to-deep sedation during anesthesia recovery observed with dexmedetomidine may be undesirable in morbidly obese patients.