Is muscle relaxant necessary in patients undergoing laparoscopic gynecological surgery with a ProSeal LMA™?

To test the hypothesis that muscle relaxant is not necessary in patients who are undergoing laparoscopic gynecological surgery with a ProSeal Laryngeal Mask Airway (ProSeal LMA™). Prospective, randomized study. Operating room of Sichuan Provincial Hospital for Women and Children. 120 adult, ASA physical status 1 and 2 women, aged 18 to 55 years. Patients were randomly assigned to two groups (n=60) to receive a muscle relaxant (Group MR) or not (Group NMR). General anesthesia was used in patients of both groups for airway management with the ProSeal LMA. Peak airway inflation pressures, airway sealing pressure, minimum flow rate, and recovery time were assessed. Surgical conditions were assessed by the operating gynecologist. The frequency of sore throats was recorded. ProSeal LMA insertion was 100% successful. Patients' lungs were ventilated with a maximum sealing pressure of 32 ± 5.1 cm H(2)O (Group MR) or 31 ± 4.9 cm H(2)O (Group NMR) (P = 0.341). The seal quality in both groups permitted the use of low flows: 485 ± 291 mL/min in Group MR and 539 ± 344 mL/min in Group NMR (P = 0.2). Surgical conditions were comparable between the two groups. There was no difference in the frequency of sore throats (20% vs 21.7%; P = 0.28). In Group NMR, there was a statistically significant reduction in recovery time versus Group MR (4.5 ± 2.6 min vs 10.3 ± 4.2 min; P < 0.01). Muscle relaxant is not necessary in general anesthesia with a ProSeal LMA.