Related Experiment Video
Updated: May 27, 2025
Ex Vivo Porcine Experimental Model for Studying and Teaching Lung Mechanics
Published on: April 19, 2024
Manual Ventilation Performance With Safety Device in Normal Versus Decreased Lung Compliance: A Single-Center
Prasanna Kumar1, Rachel Culbreth2, Douglas S Gardenhire3
1Drs Kumar and Brady are affiliated with Alpert Medical School of Brown University, Department of Emergency Medicine, Providence, Rhode Island.
None:
Background: Resuscitator bags are commonly utilized in acute care settings; however, poor performance occurs irrespective of a provider's qualifications or experience. A new flow-limiting device (Sotair by SafeBVM, Boston, Massachusetts) limits inspiratory flow during manual ventilation, thus minimizing peak inspiratory pressures. This study examined the differences in flow, pressure, and tidal volume (VT) during ventilation with a manual resuscitator connected to the flow-limiting device versus a mechanical ventilator. Methods: Second-year respiratory therapy students were recruited from an advanced cardiovascular life support class. Participants conducted a 2-min trial of manually ventilating a test lung utilizing normal and decreased compliance settings with the flow-limiting device connected to an endotracheal tube. Demographic data on participants' age were collected. The control group consisted of a mechanical ventilator providing ventilation with the same test lung and compliance settings. Mean differences were compared between the manual ventilation and control group. Results: A total of 41 respiratory therapy students (71% female, 76% undergraduate) participated. The mean experience level using the bag-valve-mask was 6.71, and the mean confidence level was 8.02; the scale was 0-10 with high numbers indicating greater experience or confidence. A small but statistically significant difference was found in mean peak pressures between manual ventilation with the flow-limiting device (15 cm H2O) and the mechanical ventilator (13 cm H2O) for the normal lung setting (P = .008) but not for the decreased compliance lung setting (23 cm H2O vs 23 cm H2O with the ventilator). There was a significant difference in mean VT between manual ventilation (412 mL) and the mechanical ventilator (460 mL) in the decreased compliance lung setting (P = .003) but not the normal compliance setting (452 mL vs 474 mL with the ventilator). Conclusions: Although there were some statistically significant differences between the 2 groups, these differences were not clinically important. Participants adequately manually ventilated with VT similar to a mechanical ventilator.
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