Original Article

Survival of Trauma Victims Transported by Helicopter Who Required Cardiopulmonary Resuscitation Within the First Hour of Hospital Arrival

Authors: Nasim Ahmed, MBBS, FACS

Abstract

Objectives: The purpose of the study was to review the impact on survival of trauma victims who were transported via helicopter ambulance versus ground transportation and who received cardiopulmonary resuscitation (CPR) within 1 hour of hospital arrival.

Methods: A retrospective analysis of the trauma patients who underwent CPR within 1 hour of arrival to the trauma centers and transported either via air or ground ambulances was performed. Data were extracted from the Research Data Set 2007–2010 from the American College of Surgeons National Trauma Data Bank. Patient and hospital characteristics were compared between the groups. Propensity score matching was performed to balance the baseline characteristics and absolute risk reduction was calculated using the McNemar test to evaluate the risk difference of survival at discharge with the mode of transportation.

Results: A total of 1269 patients qualified for the final analysis; 314 patients were transported by helicopter and 955 by ground ambulances. There were significant differences in baseline characteristics between the groups regarding age ( P = 0.015), Injury Severity Score ( P < 0.001), Glasgow Coma Scale ( P < 0.001), male sex ( P < 0.001), race ( P < 0.001), and injury type (blunt vs penetrating, P < 0.001). After propensity score matching, no significant differences were seen on baseline characteristics between the groups. The mean standardized difference was <10% between the groups after matching in all covariates. There was a higher rate of survival of patients who were brought in via helicopter ambulance (absolute risk reduction 0.066, confidence interval 0.008–0.125, P = 0.02).

Conclusions: Higher survival was seen in patients who were transported by helicopter ambulance and received CPR within 1 hour of hospital arrival.

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