Related Experiment Video
Updated: Jul 16, 2026

Ex Vivo Porcine Experimental Model for Studying and Teaching Lung Mechanics
Published on: April 19, 2024
Impact of a pressure-responsive flow-limiting valve on bag-valve-mask ventilation in an airway model
Jonnathan M Busko1, Thomas H Blackwell
1Department of Emergency Medicine, Carolinas Medical Center, Charlotte, North Carolina 28203, USA. jbuskomd@yahoo.com
Objective:
Using a simulated airway model, we compared ventilation performance by emergency medical services (EMS) providers using a traditional bag-valve-mask (Easy Grip) resuscitator to their performance when using a new device, the SMART BAG resuscitator, which has a pressure-responsive flow-limiting valve.
Methods:
We recruited EMS providers at an EMS educational forum and performed a randomized, non-blinded, prospective crossover comparison of ventilation with 2 devices on a non-intubated simulated airway model. Subjects were instructed to ventilate a Mini Ventilation Training Analyzer as they would an 85-kg adult patient in respiratory arrest. After being randomized to order of device use, they performed ventilation for 1 minute with each device. Primary outcomes were ventilation rates and peak airway pressures. We also measured average tidal volume, gastric inflation volume, minute ventilation and inspiratory:expiratory (I:E) ratio, and compared our results to the American Heart Association standards (2005 edition).
Results:
We observed statistically significant differences between the SMART BAG and the traditional bag-valve-mask for respiratory rate (12 v. 14 breaths/min), peak airway pressure (15.6 v. 18.9 cm H(2)O), gastric inflation (239.6 v. 1598.4 mL), minute ventilation (7980 v. 8775 mL), and I:E ratio (1.3 v. 1.1). Average tidal volume was similar with both devices (679.6 v. 672.2 mL).
Conclusion:
The SMART BAG(R) provided ventilation performance that was more consistent with American Heart Association guidelines and delivered similar tidal volumes when compared with ventilation with a traditional bag-valve-mask resuscitator.
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