Ventilating the Bearded: A Randomized Crossover Trial Comparing a Novel Bag-Valve-Guedel Adaptor to a Standard Mask.

Abstract

Emergency field ventilation using bag-valve face mask devices can be difficult to perform, especially in bearded individuals. In view of the increasing numbers of servicemen and civilians sporting a beard or moustache, the issue of finding a technical solution for ventilation in this population has gained importance. We therefore developed a novel adaptor that enables the direct connection of a bag-valve device to a Guedel-type oropharyngeal airway device thereby directly connecting the oral airway to the bag valve, eliminating the need for a face mask. The objective of this study was to compare the efficacy of the bag-valve-Guedel adaptor (BVGA) to the common face mask in healthy bearded volunteers. This study was a randomized-by-sequence, crossover-controlled trial (NCT02768246) approved by the local IRB (0051-16-HMO). All subjects signed an informed consent before participation. Twenty-five healthy bearded men (age 28±7) were recruited. After randomization, the first group (mask then BVGA, n=12) began breathing room air through the face mask, followed by 100% O2. After washout in room air, the procedure was repeated with the BVGA. The second group (BVGA then mask, n = 13) began with the BVGA followed by the face mask. Subjects were awake and breathed spontaneously throughout the experiment. Therefore, a Guedel was not used. Physiological and respiratory parameters were monitored continuously. The primary endpoint was the presence of suspected leak as determined by end-tidal-CO2 (EtCO2<20mmHg). Secondary endpoints included tidal volume and safety. The order of device use did not affect the results significantly (p>0.05 by Mann-Whitney-U test); therefore, the data were pooled. There were no cases of suspected leak while breathing through the BVGA. By contrast, while breathing through a face mask, there were 8 of 25 (32%) and 5 of 25 (20%) cases of suspected leak in air and 100% O2, respectively (air: p=0.002; 100% O2: p=0.014 by McNemar test). No adverse events were observed. In bearded individuals, the BVGA provides significantly more efficient (less leak) ventilation compared to a face mask. This is also of particular importance in view of the increasing number of bearded individuals serving in the armed forces. Moreover, since effective ventilation with a mask requires experience, the relatively easy-to-apply BVGA will enable less experienced first responders to achieve higher success rates in this critical phase of treatment. Further studies are planned to evaluate the efficacy of the BVGA in the prehospital setting.