i-gel™ supraglottic airway in clinical practice: a prospective observational multicentre study.

Background: The i-gel™ supraglottic airway device has been studied in randomized controlled studies, but it has not been evaluated in a large prospective patient cohort. Therefore, we performed this prospective multicentre observational study to evaluate success rates, airway leak pressure, risk factors for i-gel failure, and adverse events.

Methods: With Ethics Committee approval and waiver of patients' consent, data about anaesthesia providers, patient characteristics, and the performance of the i-gel were recorded in five independent hospitals in Switzerland over a period of 24 months. We analysed success rates, leak pressures, adverse events, and risk factors for failure.

Results: Data from 2049 i-gel uses were analysed. Patients' mean age was 47 (range 6-91) yr. The primary i-gel success rate without changing size was 93%; the overall success rate was 96%. Insertion was deemed very easy or easy in 92%. The mean airway leak pressure was 26 (8) cm H(2)O. The mean anaesthesia time was 67 (42) min. Risk factors associated with i-gel failure were males (P<0.001), impaired mandibular subluxation (P=0.01), poor dentition (P=0.02), and older age (P<0.01). Adverse events recorded were laryngeal spasms (n=25, 1.2%), blood stained airway devices (n=79, 3.9%), transient nerve damage (n=2, 0.1%), one case of transient vasovagal asystole, and one glottic haematoma.

Conclusions: The i-gel is a reliable supraglottic airway device failing in <5% and providing high airway leak pressures. Males, impaired mandibular subluxation, poor dentition, and older age are risk factors associated with primary device failure. Serious adverse events are rare.