Comparison of Sugammadex Versus Neostigmine in Women at High Risk of Postoperative Nausea and Vomiting After Laparoscopic Gynaecological Surgery: A Randomized Controlled Trial

More than 1500 laparoscopic abdominal gynaecological surgeries are performed at our Hospital every year and hence there is a need to provide excellent analgesia and minimize side effects from medications to improve patient satisfaction and outcomes. Postoperative nausea and vomiting (PONV) may occur in 30% of women undergoing gynaecological surgery. In a patient population with multiple risk factors (e.g. female gender, duration of surgery > 2 hours, non-smoker, history of PONV or a history of motion sickness), the incidence is up to 80%. PONV has a significant negative effect on patient satisfaction after anesthesia and is one of the most common causes for unexpected hospital admissions in day-surgery.

The primary aim of our study is to determine whether Sugammadex would reduce the incidence of self-reported postoperative nausea after surgery in high-risk women 24-hours after undergoing laparoscopic gynaecological surgery, when compared to Neostigmine. The secondary aims are to investigate the effects of Sugammadex on the severity of self-reported PONV at 6-hour; the quality of recovery score at 24-hours; total number of patients with PONV, pain intensity and overall satisfaction score with anaesthesia following laparoscopic gynaecological surgery in high-risk women. This study is intended as a double-blinded, randomised, single-center trial at KK Women's and Children's Hospital.

Sugammadex is a selective relaxant-binding agent that provides rapid reversal from neuromuscular blockade induced during general anaesthesia to facilitate surgical procedures. The main advantage of sugammadex is that its action is not dependent on inhibition of acetylcholinesterase when compared to traditional reversal agents such as Neostigmine. Therefore, sugammadex is not associated with the cholinergic side effects like nausea, vomiting and bradycardia. This present study intends to provide a new, effective anaesthetic regimen producing a reduction in side effects from surgery and anaesthesia, with higher patient satisfaction.

Sugammadex was identified as the first selective relaxant-binding agent providing rapid reversal from neuromuscular blockade induced during general anaesthesia when used to facilitate surgical procedures (Welliver 2006). The mechanism of Sugammadex differs from that of other commonly used reversal agents, such as neostigmine and edrophonium, which are reversible acetylcholinesterase inhibitors.

Neostigmine relies on inhibition of acetylcholinesterase, causing autonomic instability and side effect like headache, blurred vision, slowing of the heart rate (bradycardia), and gastrointestial symptoms including anorexia, nausea, vomiting, abdominal cramps and diarrhea. Hence, an anticholinergic drug such as atropine has to be administered concurrently to prevent excessive muscarinic effects such as bradycardia (Gilman 1980). A previous study (Lovstad et al 2001) showed that neostigmine increases the incidence of postoperative nausea and vomiting after gynaecological surgery compared to a placebo. However, in the current practice of providing neuromuscular blockade for laparoscopic surgery, maintenance of neuromuscular blockade is required to facilitate surgery, thereby making reversal agents necessary to prevent postoperative residual neuromuscular blockade.