1. National Priority Consultants, Inc., National Academy of Emergency
Medical Dispatch, Salt Lake City, Utah USA
Introduction: Emergency medical-vehicle collisions (EMVCs) occurring during initial response and transport have been a long-standing problem for EMS systems. Our own experience suggests the existence of "wake-effect" collisions occurring as a result of an EMS vehicle's transit, but not involving the EMV. Substantiating the existence and magnitude of wake-effect collisions may have major implications regarding the manner of EMV response.
Hypothesis: Paramedics, when surveyed, will report that wake-effect collisions do occur and that they occur more frequently than EMVCs.
Methods: Design: Survey analysis. Participants: Thirty paramedics employed by the Salt Lake City, Utah, Fire Department and 45 paramedics employed by the Salt Lake County Fire Department. Geographic Area: Service area has population of 650,000 and is urban, suburban, and rural. Measurements: The survey consisted of three open-ended questions concerning years on the job, EMVCs, and wake-effect collisions. Analysis: The mean EMVCs and wake-effect EMVCs, along with the 0.95 confidence intervals (0.95 CI) were determined.
Results: Seventy-three surveys were analyzed. Sixty EMVCs and 255 wake-effect collisions were reported. Overall, the mean EMVCs reported per respondent were 0.82 (0.60-1.05) and for wake collisions 3.49 (2.42-4.55). Emergency medical-vehicle collisions means for each fire service were 0.86 (0.50-1.38); 0.80 (0.50-11.0). For wake-effect collisions the means were 04.59 (2.83-6.35); 2.76 (1.46-4.06).
Conclusions: Our study suggests that the wake-effect collision is real and may be occurring more frequently than EMVCs. Significant limitations of this study are recall bias and also misclassification bias. Future studies are needed to define more precisely wake-effect collision prevalence and the resulting "cost" in regard to injury and vehicle/property damage.