Randomized comparison of the i-gel^TM with the LMA Supreme^TM in anesthetized adult patients

The LMA Supreme^TM (LMA-S) and i-gel^TM are two of the most commonly used supraglottic airway devices (SADs) with an inbuilt drain channel. These devices are particularly indicated for performing certain procedures accompanied by high peak airway pressure, such as laparoscopy. This study compared the devices regarding efficacy, safety, ease of use and incidence of adverse events, focusing on the postoperative rate of sore throat, dysphagia or dysphonia and development with time, in patients undergoing laparoscopic cholecystectomy procedures under general anesthesia.

This was a prospective, randomized, controlled clinical study including 140 patients randomized into 2 groups undergoing elective laparoscopic cholecystectomy to use either i-gel or LMA-S. After the general anesthesia procedure, the speed of insertion, success rates, ease of insertion of the drain tube, leak pressure and tidal volume achieved by the devices were evaluated. The postoperative oropharyngeal discomfort (POPD) during the period of stay of the patients in the recovery room was also recorded.

The mean leak pressure was comparable between the two groups (i-gel 28.18 ± 3.90 cmH₂O and LMA-S 27.50 ± 4 cmH₂O, p = 0.09), as well as maximum expiratory tidal volume provided (i-gel 559.60 ± 45.25 ml and LMA-S 548.95 ± 56.18 ml, p = 0.12). Insertion times were lower for the i-gel (10 ± 1.62 s) compared with the LMA-S (11.31 ± 2.85 s, p = 0.008). Insertion success rate at the first attempt was higher for the LMA-S (95 % compared with i-gel 79 %, p = 0.007). Drain tubes were easier to insert in the LMA-S group (p < 0.001). No differences were found between groups relating to intraoperative complications. Frequency of coughing and visible blood on removal of the device were low and comparable in both groups (p = 0.860 and p = 0.623, respectively). There were no differences relating to the incidence of sore throat, dysphagia or hoarseness at 10 min postoperatively between groups (p = 0.088). The i-gel group complained about a higher sore throat score at 2 h postoperatively (p = 0.009), specifically patients receiving i-gel suffered more from sore throats with 0.24 more points on the visual analog scale (VAS) than patients from the LMA-S group. The i-gel group also reported a lower POPD drop during the first 2 h (p < 0.001).

No differences were found between i-gel and LMA-S regarding leak pressure in the groups of anesthetized patients undergoing laparoscopic cholecystectomy. The LMA-S was easier to insert than the i-gel (based on its better first time success rate) and this device showed better ease of drain tube insertion, although the i-gel was quicker to insert than the LMA-S. The i-gel resulted in higher sore throat scores at 2 h postoperatively and lower POPD reduction during the 2 h period studied in the recovery room was reported.