Influence of stressors on HEMS crewmembers in flight

Helicopter emergency medical service (HEMS) crew are subject to various sources of environmental, physical, and psychological stress. We measured the changes in heart rate and blood pressure as indicators of stress among the crewmembers of the regional HEMS of the Region Friuli Venezia Giulia, Italy.

From August 12 to September 3, 2009, and from February 12 to April 1, 2010, heart rate (HR), diastolic blood pressure (DBP), and systolic blood pressure (SBP) were measured, on a voluntary basis, before and after each flight among the crewmembers. Oxygen saturation (SpO(2)) was also recorded. The effects of flight and personal characteristics on the parameters after the flight were analyzed through multivariate regression.

Data on 95 work shifts, corresponding to 162 flights, were collected. Only the HR changed significantly after the flight (median change: 15 beats/min considering all the flights). The increase in HR was significantly greater in flights with adverse weather conditions, in hostile environments, and at high altitude than in the others. The change in HR was inversely correlated with that of SpO(2). After adjusting for potential confounders, the HR after the flight was significantly higher among technical personnel than among physicians and nurses.

The increase in HR after the flight indicates that the HEMS crew are exposed to stressful conditions during the mission. Monitoring such parameters may be helpful in recognizing the onset of acute stress and ensuring the safety of the patients and the crew themselves.