The purpose of this study is to illustrate pharmacokinetics of sugammadex in reversal of vecuronium-induced neuromuscular blockade in patients during laparoscopic surgery

48 patients undergoing laparoscopic surgery were divided into 3 groups according to body mass index (BMI), including normal weight group(A group,n=16,18.5kg/m² ≤ BMI ≤ 24.9kg/m²),obese group (B group, n=16, 25≤BMI≤39.9kg/m²) and morbidly obese group (C group, n=16, BMI≥40kg/m²).

Vecuronium was continuous infusing to maintain moderate neuromuscular blockade during the laparoscopic surgery and stopped infusing after the laparoscopic procedure. A single dose administration of sugammadex (Sug) 2.0mg/kg according to ideal body weight (IBW) was given at the reappearance of the second twitch of the train-of-four (TOF) response.

On one hand, venous blood samples were obtained before administration of Sug and at 2, 3, 5, 10, 15, 20, 30, 60 minutes and 2, 4, 6, 8 hours after administration of Sug to determine plasma concentration of Sug using HPLC-MS. On the other hand, time from start of administration of Sug to recovery of TOF ratio to 0.9 and other clinical indicators were also recorded.

Inclusion Criteria:

1. ASA: Ⅰ~Ⅲ
2. BMI≥25kg/m²
3. Patients receiving bariatric surgery.

Exclusion Criteria:

1. Pregnant or lactating women
2. Neuromuscular diseases
3. Malignant hyperthermia or allergic history during general anesthesia
4. Drugs that react with rocuronium and vecuronium were taken