Emergency Medical Services
Background: The emergency department (ED) relies heavily on estimated times en route (ETE) provided by emergency medicine services (EMS) to ensure appropriate patient flow, mobilization of services and allocation of resources. Grossly inaccurate ETEs can have an immediate negative impact on patient care in the ED and the additive effect of chronic ETE underestimation could significantly effect the downstream flow of patients and services within an entire hospital.
Methods: This was a prospective, observational study of the ED patients arriving via ground EMS. Registration and nursing staff recorded the required information on standardized data collection forms, including patient demographics, EMS unit numbers, time of notification, ETE, and actual time of arrival, defined as time of contact with registration staff. The primary outcome was the difference between EMS-reported ETE and actual time en route (ATE). EMS-provided ETE and actual time en route (ATE) were compared using the two-sided Wilcoxon Signed-Rank Test with p < 0.05 considered significant.
Results: To date, data has been collected for 148 consecutive ED patients arriving via ground EMS. After excluding 44 for missing data, a total of 104 were included for preliminary analysis. Median patient age was 61.5 years (IQR 42.25-75, range 4-94) and 46.2% were female. The median ETE and ATE were 5 min (IQR 5-10, range 2-20) and 10 min (IQR 8-12, range 4-57), respectively. There was a significant difference between ETE and ATE (median 3 min, IQR 1-5, range -4-48, Z=-7.785, p < 0.001).
Conclusion: Our preliminary results suggest that EMS consistently underestimates the time required to reach the ED. Further study is needed to confirm these findings and assess the effects of ETE inaccuracy on specific patient subgroups and hospital services.