Helicopter versus ground ambulance transport for interfacility transfer of critically ill children

Abstract

Background: Following initial stabilization, critically ill children often require transfer to a specialized pediatric hospital. While the use of specialized pediatric transport teams has been associated with improved outcomes for these patients, the additional influence of transfer mode (helicopter or ground ambulance) on clinical outcomes remains unknown.

Methods: We investigated the association between transport mode and outcomes among critically ill children transferred to a single pediatric hospital via a specialized pediatric transport team. We designed a retrospective cohort study to reduce indication bias by limiting analysis to patients for whom a helicopter transport was initially requested. We compared outcomes for those who ultimately traveled via helicopter, and for those who ultimately traveled via ground ambulance due to non-clinical factors.

Results: We compared transport times, in-hospital mortality, and hospital length of stay by transport mode. Transport time in minutes was shorter for helicopter transports (median = 143, interquartile range [IQR]: 118-184) compared to ground ambulance transports (median = 289, IQR: 213-258; difference in medians = 146, 95% CI: 12 to 168, p < 0.001). In unadjusted analysis, helicopter transport was not associated with a difference in in-hospital mortality (helicopter = 6.0%, ground ambulance = 7.0%; 95% CI for difference: -6.6% to 3.3%; p = 0.64) but was associated with a statistically significant reduction in median hospital days (helicopter = 4, ground ambulance = 5; 95% CI -3 to 0; p = 0.04). In adjusted analyses, there were no statistically significant associations. These results were consistent across sensitivity analyses.

Conclusions: Among critically ill pediatric patients without traumatic injuries transported by a specialty team, those patients who would have been transferred by helicopter if available but were instead transferred by ground ambulance reached their site of definitive care approximately 2.5 h later. Helicopter transport for these patients was not associated with in-hospital mortality, but was potentially associated with reduced hospital length of stay.

Keywords: Air ambulances; Critical care; Emergency departments; Outcomes; Pediatrics.