Emergency medical service transport-induced stress? An experimental approach with healthy volunteers

This randomized controlled trial was designed to evaluate the effects of simulated emergency medical service (EMS) transport related stress on hemodynamic variables, and catecholamine plasma levels. A total of 32 healthy male volunteers were randomized to being carried by paramedics from a third-floor apartment through a staircase with subsequent high-speed EMS transport with lights and sirens (stress; n = 16); or sitting on a chair for 5 min, and lying on a stretcher for 15 min (control; n = 16). Blood samples and hemodynamic variables were taken in the apartment before transfer, at the ground floor, and at the end of EMS transport in the stress group, and at corresponding time points in the control group. The stress versus control group had both significantly (P < 0.05) higher mean ± SEM epinephrine (71 ± 7 versus 37 ± 3 pg/ml), and norepinephrine (397 ± 29 versus 299 ± 28 pg/ml) plasma levels after transport through the staircase. After EMS transport, the stress versus control group had significantly higher epinephrine (48 ± 6 versus 32 ± 2 pg/ml), but not norepinephrine (214 ± 20 versus 264 ± 31 pg/ml) plasma levels. Heart rate increased significantly from 72 ± 2 to 84 ± 3 bpm after staircase transport, but not during and after EMS transport. In conclusion, volunteers being carried by paramedics through a staircase had a significant discharge of both epinephrine and norepinephrine resulting in increased heart rate, but only elevated epinephrine plasma levels during EMS transport. Transport through a staircase may reflect more stress than emergency EMS transport.