Comparison Of Airway Sealing Pressure Between Proseal Laryngeal Mask Airway And I-Gel Supraglottic Airway In Adult Patients Undergoing Laparoscopic Surgeries Requiring General Anaesthesia – A One Year Hospital Based Randomized Clinical Trial

Abstract

Introduction: Airway management by anaesthesiologists has come a long way from the invention of endotracheal intubation. Invention of Supraglottic airway devices (SAD) provided alternate ways to establish definitive airway without hazards of direct laryngoscopy and intubation. First generations SAD were considered airway tubes, and hence modifications were made to make them better. The proseal laryngeal mask airway (PLMA) is a second generation SAD, which has a gastric drain port along with the airway tube. It has been a boon to anaesthesiologists ever since it came into clinical practice. The i-gel (intersurgical) is a recent novel second generation SAD designed to fit the pharyngeal, laryngeal and perilaryngeal structures without use of an inflatable cuff. Hence, we designed this study to compare the clinical efficacy of PLMA and i-gel for ease of insertion, duration of insertion, airway sealing pressure and complications in anaesthetized, paralysed adult patients undergoing positive pressure ventilation under general anaesthesia for laparoscopic surgeries. Methodology: The present randomized clinical trial was conducted in 60 ASA I and II patients, aged between 18-60 years posted for elective laparoscopic surgeries under general anaesthesia in KLES Dr. Prabhakar Kore charitable Hospital and Medical Research Centre, Belagavi. Patients were allocated into two equal groups, Group P. PLMA (n=30) and Group I. i-gel (n=30). All the data collected were analysed. The demographic data, duration of insertion and airway sealing pressure were analysed using unpaired‘t’ test. Sex and complications were compared using chi square test. Ease of insertion was analysed using fisher exact test. Results: In our study we observed that, i-gel was easier to insert in comparison to PLMA. Difficult insertion was seen in 10 patients in PLMA group (33%) and 4 patients in i-gel group (13%) with statistically significant difference (p=<0.0001). The mean duration of insertion was 16.9 + 3.39 sec in PLMA group and 12.63 + 2.04 sec in i-gel group which was statistically significant (p<0.0001). Soon after the insertion of SAD, PLMA provided a more effective seal than i-gel for positive pressure ventilation. But as the procedure progressed, effective seal was better with i-gel than PLMA. The mean airway sealing pressure soon after insertion was 25.3 + 3.395 cm of H2O in PLMA group and 21.933 + 1.76 cm of H2O in i-gel group which was statistically significant (p<0.0001). The mean airway sealing pressure after 30 min of pneumoperitoneum and after 30 min of trendelenburg position was 21.733 + 2.016 cm of H2O in PLMA group and 27.767 + 1.716 cm of H2O in i-gel group; 20.267 + 1.617 cm of H2O in PLMA group and 24.133 + 2.097 cm of H2O in i-gel group respectively. Incidence of post operative hoarseness of voice was higher in PLMA group than i-gel group, but was statistically insignificant. Conclusion: To conclude, we observed that, i gel was easier to insert than PLMA in anaesthetized paralysed adult patients, and the time taken for successful insertion was shorter with i-gel than with PLMA. Mean airway sealing pressure was initially higher in PLMA group with statistical significance, but as the surgery progressed, airway sealing pressure of i-gel was significantly higher than with the PLMA group. Incidence of post-operative hoarseness of voice was higher in PLMA group, though statistically insignificant.