Factors related to prolonged on-scene time during ambulance transportation for critical emergency patients in a big city in Japan: A population-based observational study

Abstract

Objectives: We aimed to investigate the factors related to prolonged on-scene times, which were defined as being over 30 min, during ambulance transportation for critical emergency patients in the context of a large Japanese city. Design: A population-based observational study. Setting: Kawasaki City, Japan fseighth largest city. Participants: The participants in this study were all critical patients (age .15 years) who were transported by ambulance between April 2010 and March 2013 (N=11 585). Outcome measures: On-scene time during ambulance transportation for critical emergency patients. Results: The median on-scene time for all patients was 17 min (IQR 13.23). There was a strong correlation between on-scene time and the number of phone calls to hospitals from emergency medical service (EMS) personnel ( p>0.001). In multivariable logistic regression, the number of phone calls to hospitals from EMS personnel, intoxication, minor disease and geographical area were associated with on-scene times over 30 min. Age, gender, day of the week and time of the day were not associated with onscene times over 30 min. Conclusions: To make on-scene time shorter, it is vital to redesign our emergency system and important to develop a system that accommodates critical patients with intoxication and minor disease, and furthermore to reduce the number of phone calls to hospitals from EMS personnel.