Comparative Evaluation of ProSeal LMA vs. Cuffed Endotracheal Tube in Patients Undergoing Laparoscopic Cholecystectomy under General Anesthesia

Proseal LMA (PLMA) has been used for airway maintenance during laparoscopic cholecystectomy. However, there is limited data regarding the effects of pneumoperitoneum, particularly on pulmonary mechanics. Objective of the present study was to evaluate and compare the use of PLMA with a cuffed endotracheal tube (ETT) with regard to changes in pulmonary mechanics, haemodynamic variables, degree of gastric inflation, ease of device insertion and possible adverse events in patients undergoing laparoscopic cholecystectomy. After written informed consent and institutional ethics committee approval, we enrolled one hundred patients (ASA physical status1/2), 18-60 years of age who were scheduled to undergo laparoscopic cholecystectomy under general anesthesia (GA). Patients were randomly allocated to one of the two groups of 50 each. Group 1: cuffed endotracheal tube and Group 2: ProSeal LMA. Patients as well as the surgeons were blinded to the airway device used. Insertion parameters, haemodynamic and ventilatory parameters (compliance, resistance and peak/plateau airway pressure) were measured at different time intervals before, during and after pneumoperitoneum. Statistically significant (p< 0.05) but clinically insignificant difference was found in time taken for device insertion in the two groups (21.8 ± 5.9 s group I & 25.4 ± 5.7 s group II). Insertion of orogastric tube was easier and less number of attempts was required with PLMA. Hemodynamic parameters like heart rate, systolic, diastolic and mean blood pressures increased after the ETT insertion while there was a decrease/no change after PLMA insertion. There was a significant decline in the pulmonary compliance in Group 2, which was more pronounced after pneumoperitoneum. During pneumoperitoneum, higher peak and plateau airway pressures were noted in PLMA group than in ETT group. After desufflation these parameters returned to near pre-insufflation levels. There was no episode of arterial desaturation or end tidal carbon dioxide changes in either group. Our results indicate that in the PLMA group, the degree of changes in pulmonary mechanics caused by the pneumoperitoneum were significant however there was no incidence of arterial desaturation, or gastric regurgitation. Due to better hemodynamic stability with PLMA, it may even be better alternative than ETT in hypertensive/cardiac patients. Hence PLMA is a satisfactory airway device for laparoscopic cholecystectomy under GA, but further studies are required regarding its safety in patients with decreased pulmonary compliance like morbid obesity or obstructive pulmonary disease.