Ventilation in Simulated Out-of-Hospital Cardiac Arrest Resuscitation Rarely Meets Guidelines

Abstract

Objective

The American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care recommend ventilation rates of eight to ten breaths per minute or two ventilations every 30 compressions, and tidal volumes between 500–600 ml. However, compliance with these guidelines is mainly unknown. The objective of this study is to estimate the proportion of simulated adult OHCA cases that meet guideline-based ventilation targets.

Methods

We conducted a blinded prospective observational study of standardized simulated cases of EMS-witnessed adult OHCA. During scheduled training sessions, resuscitations were performed by high-quality CPR trained EMS teams composed of four on-duty, full-time EMT/Paramedics from a large urban fire-based EMS agency. A high-fidelity simulation center allowed complete audio and video monitoring from a control room. Rescuers were unaware of the study, or that ventilation practices were being observed. All interventions, including airway and ventilation strategies, were at the discretion of the clinical team. A calibrated Laerdal SimMan 3 G manikin and associated Laerdal Debrief Viewer software recorded ventilation rate, tidal volume, and minute ventilation. Simulations achieving median ventilation rate 7–10 breaths/min, tidal volume 500–600 ml, and minute ventilation 3.5–6 liters/min were considered meeting guideline-based targets.

Results

A total of 106 EMS teams were included in the study. Only 3/106 [2.8% (95% CI: 0.6–8.0)] of the EMS teams demonstrated ventilation characteristics meeting all guideline-based targets. The median ventilation rate was 5.8 breaths/min (IQR 4.4–7.7 breaths/min) with 26/106 [24.5% (95% CI: 17.2–33.7)] between 7–10 breaths/min. The median tidal volume was 413.5 ml (IQR 280.5–555.4 ml), with 18/106 [17.0% (95% CI: 10.9–25.5)] between 500–600 ml. The median minute ventilation was 2.4 L/min (IQR 1.2–3.6 L/min) with 16/106 [15.1% (95% CI: 9.4–23.3)] between 3.5–6.0 L/min.

Conclusion

During simulated adult OHCA resuscitation attempts, ventilation practices rarely met guideline-based targets, despite being performed by well-trained EMS providers. Methods should be developed to monitor and ensure high-quality ventilation during actual OHCA resuscitation attempts.

Key words:

• out-of-hospital cardiac arrest
• ventilation rate
• tidal volume
• minute ventilation
• EMT
• prehospital
• simulation
• assessment

Additional information

Funding

The study was supported by the National Association of EMS Physicians and the AMR Foundation for Research and Education EMS Fellows Research Grant.