Background: Previous studies proposed that ventilation with pediatric-sized bag-valve-mask (BVM) ventilation resulted in more appropriate tidal volume (Vt) in adult patients than adult-sized BVM ventilation. However, those studies were conducted in stationary, non-moving environment. The authors hypothesized that the result of BVM ventilation in this treatment setting may be different when the investigation was conducted in a moving ambulance.

Objective: To compare pediatric-sized and adult-sized BVM ventilation for achieving appropriate Vt in simulated adult out-of-hospital cardiac arrest (OHCA) in a moving ambulance.

Materials and Methods: The present study was a randomized crossover trial. Registered nurses (RNs) and basic emergency medical technicians (EMT-Bs) were recruited to perform resuscitation ventilation on a medical training manikin. All participants performed both the pediatric-sized at 500 cc, and the adult-sized at 1,600 cc, BVM ventilation during 30 to 2 chest compressions to ventilation ratio during simulated OHCA in a moving ambulance. Adult-sized mask was used for both scenarios. The manikin was ventilated for 10 minutes during each scenario. The percentage of appropriate Vt was compared between scenarios. The percentages of low Vt at less than 400 cc and high Vt at more than 600 cc between groups were also evaluated.

Results: Fifty-two volunteers with 57.7% RNs and 42.3% EMT-Bs were included. Of those 52 volunteers, 44 had less than five years of pre-hospital ventilation experience. The mean Vt was 239.0 cc and 444.5 cc in the pediatric-sized and the adult-sized BVM groups, respectively (p<0.001). Low Vt was observed in 100% of pediatric-sized BVM ventilation. In the adult-sized ventilation group, 52.1±25.6% had appropriate Vt, 11.4±18.6% had high Vt, and 36.5±29.1% had low Vt (p<0.001).

Conclusion: A comparison between pediatric-sized and adult-sized BVM ventilation in simulated adult OHCA in a moving ambulance demonstrated the superiority of the adult-sized BVM over the pediatric-sized BVM for achieving appropriate Vt in adult OHCA.

Keywords: Bag-valve-mask ventilation; Tidal volume; Out-of-hospital cardiac arrest; Ambulance

DOI: doi.org/10.35755/jmedassocthai.2021.09.10408

Received 2 July 2019 | Revised 30 July 2021 | Accepted 3 August 2021