Prewarming of the i-gel facilitates successful insertion and ventilation efficacy with muscle relaxation: a randomized study

• We investigated the hypothesis that prewarming of i-gel shows higher sealing pressure leading to successful insertion and ventilation.
• The i-gel was warmed to 42°C for 30 minutes or kept at room temperature before insertion.
• Number of insertion trial, sealing pressure, and leak volume were measured.
• Prewarming the i-gel to 42°C demonstrated high sealing pressure and successful insertion.
• Prewarming the i-gel to 42°C showed smaller leak volume 30 seconds after mechanical ventilation initiation.

Study ObjectiveTo determine if prewarming of the i-gel (Intersurgical, Wokingham, United Kingdom) improves insertion and ventilation efficacy with muscle relaxation in patients undergoing elective surgery.DesignClinical randomized study.SettingOperating room.PatientsSixty-eight adult patients scheduled for elective surgery under general anesthesia with American Society of Anesthesiologists physical status 1-3.InterventionsThe i-gel was warmed to 42°C for 30 minutes before insertion (W group; 34 patients) or kept at room temperature (approximately 23°C) (C group; 34 patients).MeasurementsThe number of attempts for a successful insertion and the sealing pressure and leak volume 30 seconds and 30 minutes after initiating mechanical ventilation.Main ResultsThe total insertion attempts were 1 (W group, 31 cases; C group, 24 cases) and 2 (W group, 3 cases; C group, 10 cases), which was significant (P = .001). Sealing pressure was significantly higher in the W group than the C group (W group, 21.8 ± 3.7 cm H2O; C group, 18.5 ± 3.4 cm H2O; P = .001). Leak volume was significantly smaller after 30 seconds in the W group than the C group (P = .002), but not after 30 minutes (P = .69).ConclusionsPrewarming the i-gel to 42°C demonstrated a higher successful ventilation initiation.