Chest Compression Duration May Be Improved When Rescuers Breathe Supplemental Oxygen

Area of Science:

• Emergency Medicine
• Aviation Physiology
• Cardiopulmonary Resuscitation

Background:

• Chest compressions during cardiopulmonary resuscitation (CPR) are physically demanding.
• Commercial flight cabin pressure at cruise altitude simulates an altitude of 2438 m.
• This altitude reduces the fraction of inspired oxygen (FIO2) to 15%, potentially impairing CPR quality and duration.

Purpose of the Study:

• To test the hypothesis that rescuers perform fewer rounds of high-quality CPR under hypoxic conditions simulating commercial flight altitude.
• To evaluate the impact of reduced inspired oxygen on rescuer performance during simulated CPR.

Main Methods:

• A crossover simulation trial involving 16 healthy volunteers.
• Participants performed chest compressions for up to 14 2-minute rounds under two conditions: fraction of inspired oxygen (FIO2) of 0.15 (hypoxic) and 0.21 (normoxic).
• Stopping criteria included SpO2 below 80%, inadequate compression rate/depth, or rescuer fatigue/dyspnea.

Main Results:

• Fewer rounds of chest compressions were successfully completed in the hypoxic condition (median 4.5) compared to the normoxic condition (median 5).
• A greater decline in arterial oxygen saturation (SpO2) was observed during chest compressions in the hypoxic condition (6.19% decline) versus the normoxic condition (2% decline).
• Hypoxia significantly impacted rescuer performance and physiological parameters during simulated CPR.

Conclusions:

• Rescuer ability to perform high-quality chest compressions may be limited in commercial airline cabins due to reduced cabin oxygen levels.
• Supplemental oxygen for rescuers may be a viable solution to mitigate performance degradation during in-flight cardiac arrest events.
• Further consideration of in-flight medical emergency protocols is warranted.