Tissue displacement assessment by ultrasound predicts peri-laryngeal leak after supraglottic device insertion (I-gel)

Abstract

Background and aims Supraglottic airway devices (SADs) have revolutionized airway management during general anesthesia, and they fill the niche between the face mask and endotracheal tube in terms of both airway anatomy and degree of invasion. The aim of this study was assessment of peri-laryngeal leak after insertion of I- gel using ultrasound (US) pulse Doppler mode. Methods Hundred patients scheduled for elective surgery after I-gel placement were recruited. Airway leak pressure was detected by using closed circuit in anesthesia workstation and increasing the pressure to 20 mm Hg. Parameters were noted include, leak as observed in the monitor, leak as assessed using the US machine, fiberoptic visualization of the SAD and grading and end tidal CO2 (ETCO2). Results In ultrasound we have detected peri-laryngeal tissue displacement in 18 patients (18%) out of which 10 patients have grade 3 or 4 on fiberoptic examination (Fig. 2). Among these ten patients, eight patients have inadequate ventilation required reinsertion of I-gel. Conclusion Tissue displacement assessment by ultrasound can be used as a noninvasive alternative to predict leak following supraglottic device insertion (I-gel) placement with the added advantage of no interruption of ventilation.