Effectiveness of Manual Ventilation in Intubated Helicopter Emergency Services-Transported Trauma Patients

Helicopter Emergency Medical Services agencies frequently transport intubated patients to definitive care. No evidence exists to determine the type of ventilation in this population. Practice varies amongst programs from bag-valve-mask to mechanical ventilation.

Evaluate the effectiveness of bag-valve ventilation in intubated trauma patients. We hypothesized manual ventilation provides adequate support to maintain physiologic ETCO₂.

From June to December 2015, twenty patients were enrolled in this prospective, observational study. Included were endotracheally intubated trauma patients transported by this HEMS program. Excluded were interfacility transports, non-scene calls, and patients with supraglottic devices. ETCO₂ was recorded every 30 seconds during the flight. As a descriptive pilot study, power was not considered.

20 patients provided over 500 cumulative minutes of manual ventilation data. The percentage of cumulative time spent with adequate oxygen saturations was 83.6%. The percentage of cumulative time spent with adequate ETCO₂ was 48.7%, with 34.6% of time spent under and 16.7% above this range.

Manual ventilation maintained a physiologic ETCO₂ only 16.7% of the time. Significant variability existed, resulting in intermittent hypoxia and hyperventilation. Prior research linked such events to increased morbidity and mortality. Further studies are warranted to compare manual against mechanically ventilated patients.