Airway Strategy, Hypoventilation and Hyperventilation in the Pragmatic Airway Resuscitation Trial

Abstract

Background: Ventilation control is important in resuscitation from out-of-hospital cardiac arrest (OHCA). We sought to describe the incidence of hypo- and hyperventilation during resuscitation and to determine their associations with airway management strategy and OHCA outcomes.

Methods: We analyzed capnography data from the Pragmatic Airway Resuscitation Trial (PART). Using automated signal processing techniques, we determined ventilation rates for consecutive 10-second epochs. We included cases with ≥3 minutes and ≥50% of interpretable data after successful airway insertion. We defined hypo- and hyperventilation as <6 and >12 breaths/min, respectively. We compared the total and percentage of post-airway resuscitation time with hypo- and hyperventilation between LT and ETI, as well as their associations with OHCA outcomes.

Results: Of 3,004 trial patients, capnography data were available for 1,010 (LT n=714, ETI n=296). Median post-airway durations were: LT 16.4 (IQR 11.0-23.3) minutes, ETI 16.7 (10.2-22.7) minutes. Median ventilation rates were: LT 8.0 (IQR 6.5-9.6) breaths/min, ETI 7.9 (6.5-9.7) breaths/min. Total duration and percentage of time with hypoventilation were similar between LT and ETI: median 1.8 vs. 1.7 minutes, p=0.94; 10.5% vs. 11.5%, p=0.60. Total duration and percentage of time with hyperventilation were similar between LT and ETI: median 0.4 vs. 0.4 minutes, p=0.91; 2.1% vs. 1.9%, p=0.99. Hypo- and hyperventilation exhibited limited associations with OHCA outcomes.

Conclusion: In the PART trial, most post-airway ventilation rates satisfied international guidelines, with only limited episodes of hypo- and hyperventilation. Durations of hypo- and hyperventilation did not differ between airway management strategy and exhibited uncertain associations with OHCA outcomes.

Note:
Funding Information: Research Supported by Grant UH2/UH3-HL125163 from National Heart Lung and Blood Institute.

Declaration of Interests: None to declare.

Ethics Approval Statement: The Institutional Review Boards of participating institutions approved the parent study under federal regulations for Exception from Informed Consent for Emergency Research (21 CFR 50.24). This post hoc analysis was approved by the Ohio State University Office of Responsible Research Practices.

Keywords: ventilation, Cardiopulmonary arrest, airway management, intubation, emergency medical services