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Updated: Aug 14, 2025

Ex Vivo Porcine Experimental Model for Studying and Teaching Lung Mechanics
Published on: April 19, 2024
Improved simulated ventilation with a novel tidal volume and peak inspiratory pressure controlling bag valve mask: A
Jonathan G Merrell1,2, Adam C Scott2, Ryan Stambro3
1Department of Pediatrics, Indiana University School of Medicine, 340 West 10th Street, Suite 6200, Indianapolis, IN, USA.
Introduction:
The dangers of hyperventilation during resuscitation are well known. Traditional bag valve mask (BVM) devices rely on end users to control tidal volume (Vt), rate, and peak inspiratory pressures (PIP) of ventilation. The Butterfly BVM (BBVM) is a novel device intending to give greater control over these parameters. The objective of this pilot study was to compare the BBVM against a traditional device in simulated resuscitations.
Methods:
Senior emergency medicine residents and fellows participated in a three-phase simulation study. First, participants used the Ambu Spur II BVM in adult and pediatric resuscitations. Vt, PIP, and rate were recorded. Second, participants repeated the resuscitations after a brief introduction to the BBVM. Third, participants were given a longer introduction to the BBVM and were tested on their ability to adjust its various settings.
Results:
Nineteen participants were included in the adult arm of the study, and 16 in the pediatric arm. The BBVM restricted Vt delivered to a range of 4-8 ml/kg vs 9 ml/kg and 13 ml/kg (Ambu adult and Ambu pediatric respectively). The BBVM never exceeded target minute ventilations while the Ambu BVMs exceeded target minute ventilation in 2 of 4 tests. The BBVM failed to reliably reach higher PIP targets in one test, while the pediatric Ambu device had 76 failures of excessive PIP compared to 2 failures by the BBVM.
Conclusion:
The BBVM exceeded the Ambu Spur II in delivering appropriate Vts and in keeping PIPs below target maximums to simulated adult and pediatric patients in this pilot study.
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