Laryngoscopy facilitates successful i-gel insertion by novice doctors: a prospective randomized controlled trial

This study investigated the hypothesis that the efficacy of insertion of the supraglottic device i-gel(®) (i-gel) can be improved by laryngoscopy and can provide better sealing pressure in anesthetized patients by novice doctors.

Eighty-four adult patients were assigned to the laryngoscopy group (L group, 42 patients) or control group (i.e., conventional blind insertion; C group, 42 patients). Anesthesia was induced with propofol and remifentanil, and rocuronium 0.6-0.9 mg/kg was administered. The number of attempts until successful insertion, sealing pressure, vital sign changes upon insertion, and subjective difficulty of insertion by novice doctors were compared between the groups.

The total number of insertion attempts was one (L group 36 cases, C group 23 cases), two (L group 6 cases, C group 18 cases), and three (L group 0 case, C group 1 case), with significant differences between groups (P = 0.007). The sealing pressure was significantly higher in the L group than in the C group (L group 22.3 ± 2.6 cmH2O, C group 19.5 ± 2.7 cmH2O, P < 0.001). Vital sign changes (heart rate and blood pressure) did not differ between the two groups. The subjective difficulty of insertion was significantly lower in the L group than in the C group (L group 26.8 ± 11.8 mm, C group 47.0 ± 15.1 mm, P < 0.001). The incidence of postoperative pharyngeal pain was significantly lower in the L group than in the C group (P < 0.001), while the incidence of hoarseness did not differ between the two groups (P = 1.00).

Our results suggest that laryngoscopy facilitates i-gel insertion by novice doctors, as reflected in the rate of successful insertions, higher sealing pressure, and lower subjective difficulty of insertion in anesthetized patients.