AMBULANCE ARRIVAL TO PATIENT CONTACT - THE HIDDEN COMPONENT OF PREHOSPITAL RESPONSE-TIME INTERVALS

Study objective: To determine the time between ambulance arrival at th e scene to paramedic arrival at the patient (arrival to patient contac t) and the effect of barriers to paramedic movement on this time inter val. Design: A prospective, observational study. Time intervals were c ollected by independent third-party riders on emergency (Code 1 and Co de 2) calls. Potential barriers to paramedic movement were recorded. S etting: Public utility model urban emergency medical services system. Type of participants: Two hundred thirty-two emergency ambulance calls were observed, and data were analyzed from 216. Interventions: None. Results: The median arrival-to-patient contact interval for all calls was 1.33 minutes (interquartile range, 0.67 to 4.13 minutes). Barriers prolonged the arrival-to-patient contact interval (P<.001, Kolmogorov -Smirnov test). The median arrival-to-patient contact interval was 2.2 9 minutes (1.01 to 4.82 minutes) for 122 runs with barriers and 0.82 m inutes (0.37 to 1.96 minutes) for 94 runs without barriers. Conclusion : The arrival-to-patient contact interval adds a variable and potentia lly lengthy amount of time to the total prehospital response time inte rval, and barriers impeding paramedic movement to the patient prolong this time interval. In 25% of all observed paramedic calls, the arriva l-to-patient contact interval was more than four minutes. Measurement of the time from ambulance arrival on the scene to paramedic arrival a t the patient is necessary to appropriately determine the relationship among total prehospital response time, paramedic interventions, and p atient outcome.