I-gel supraglottic airway use is efficient and safe during minimal flow anesthesia with volume controlled ventilation - a randomized controlled trial

Background: A fear of potential gas leak limits the wide spread use of minimal flow anesthesia with supraglottic airway devices. Second generation supraglottic airway devices have been claimed to be come with good airway seal. I-gel is one of these and it has been extensively evaluated for spontaneous as well as assisted ventilation. We conducted this study to evaluate its use with low flow anesthesia and volume controlled ventilation. Methodology: In a prospective randomized controlled trial, 50 patients undergoing laparoscopic surgeries for less than 2 h duration were administered general anesthesia, with controlled ventilation, using either endotracheal tube or an I-gel for airway control. The total fresh gas flow was gradually reduced until it was 400 mL/min. Patients were monitored for evidence of loss of respiratory gas volume in the breathing circuit and other parameters for ventilation failure. Results: Ventilation could be maintained at a fresh gas flow of 400 mL/min, without clinical or volumetric evidence of gas leak in all patients in the two groups. Two patients in the I-gel group had intraoperative gas leak leading to ventilator failure alarm but the same was corrected by repositioning of the head. The vital signs, peak airway pressure, end-tidal carbon dioxide, set tidal volume and expired tidal volumes were statistically similar in the two groups. Conclusion: I-gel supraglottic airway can be safely and efficiently used for laparoscopic surgery using minimal flow anesthesia and volume controlled ventilation. Citation: Khan A, Kapoor MC, Garg S, Puri A, Sinha A. I-gel supraglottic airway use is efficient and safe during minimal flow anesthesia with volume controlled ventilation - a randomized controlled trial. Anaesth pain intensive care 2020;24(1):__ Abbreviations: Supraglottic airway device – SAD; Volume controlled ventilation – VCV; Pressure controlled ventilation – PCV; Endotracheal tube – ETT; Laryngeal Mask Airway - LMA DOI: https://doi.org/10.35975/apic.v24i1. Received – 11 June 2019; Reviewed – 20, 23 October 2019; Revised – 31 January 2020; Second Review – 2, 7 January 2020; Accepted – 02 February 2020