Effectiveness of Ventilation via an Endotracheal Tube in Pharynx Versus a Facemask in Patients With Potentially Difficult Airway: A Randomized, Crossover, and Blind Trial.

Abstract

The difficult airway is frequently encountered across many scenarios. The extreme form is a "cannot intubate and cannot oxygenate" scenario, which lacks a reliable rescue technique. Previous case reports or studies with small sample sizes indicate the feasibility and efficiency of an endotracheal tube in the pharynx (TTIP) to ventilate patients. We hypothesize that ventilation via TTIP is an effective rescue technique for failed mask ventilation. One hundred forty-seven patients with potentially difficult airways were randomly assigned to the sequence (Tube first) of tube first ventilation via TTIP for 1 minute after induction, followed by via mask ventilation for 1 minute or in reverse sequence (Mask first). The ventilation was done with pressure control mode, a peak inspiratory airway pressure of 20 cmH 2 O, an inspiratory to expiratory time ratio of 1:2, and a respiratory rate of 10 breaths/min. A total of 136 patients underwent final analysis. The overall success rate (primary outcome) of ventilation via TTIP and mask, defined as the presence of expired carbon dioxide, was 93.4% (127/136) and 84.6% (115/136), respectively ( P = .02). The success rate, 85.7% (6/7), of mask ventilation rescuing a failed TTIP ventilation and 100% (13/13) of TTIP rescuing a failed mask ventilation were comparable ( P = .35). The success rates of TTIP and mask ventilation are comparable. Ventilation via TTIP could be an alternative rescue technique for managing a difficult airway.