T. W. Clements1, K. Vogt3, M. Hameed2, N. Parry3, A. Kirkpatrick1, S. Grondin1, E. Dixon1, J. Mckee1, C. Ball1 1University Of Calgary,Division Of General Surgery,Calgary, AB, Canada 2University Of British Columbia,Vancouver, British Columbia, Canada 3Western University,London, ONTARIO, Canada 4University Of Calgary – Cumming School Of Medicine,Calgary, AB – ALBERTA, Canada
Introduction: Emergency medical services (EMS) prehospital times vary substantially between different regions. The impact of these times on trauma team activation (TTA) and patient survival is unknown. The aim of this study was to identify the impact of EMS prehospital time on resource utilization (TTA) and patient outcomes.
Methods: A multi-institutional study from 3 geographically distinct regions (level 1 trauma centers) reviewed all severely blunt injured patients (ISS>12) to determine the relationship between prehospital times (30 minute increments), hemodynamic instability(sBP<100), TTA, and patient outcomes. Standard statistical methodology was employed.
Results:From January 2011 to January 2016, 6881 severely blunt injured patients (mean ISS = 24.6; LOS = 16.3 days) were evaluated (Calgary 3376; Vancouver 2401; London 1104). As the prehospital time interval increased, the overall mortality rate decreased (0-30min: = 24.1%; 31-60min = 14.7%; 61-90min = 10.3%; 91-120min = 10.4%;121-150min = 10.2%; 151-180min = 12.1%; p<0.05). Although centers varied in overall injury severity (ISS) and prehospital system formats, this pattern of decreasing mortality with longer prehospital time was consistent across all 3 regions (p>0.05). TTA was variable across time intervals (0-30min: = 51.9%; 31-60min = 25.4%; 61-90min = 17.1%; 91-120min = 26.3%; 121-150min = 27.1%; 151-180min = 29.9%; p<0.05) and only variably related to ISS. Hemodynamic instability was predictive of mortality in all prehospital intervals (p<0.05).
Conclusion: TTA criteria must improve to select appropriate patients who have a prehospital transport time less than 30 minutes and a high mortality. Patients with prehospital times more than 60 minutes and hemodynamic stability rarely require life-saving interventions and TTA. Longer prehospital times lead to a ‘trial of life’ preselection scenario with decreasing overall mortality regardless of the regional trauma system structure.