Objectives: Transport of pediatric patients is common due to healthcare regionalization. We set out to determine the frequency of in-transit critical events during pediatric critical care transport and identify factors associated with these events.
Design: Retrospective cohort study using administrative and clinical data.
Setting: Single pediatric critical care transport provider in Ontario, Canada.
Patients: All pediatric care transports between January 1, 2005, and December 31, 2010.
Measurements and main results: The primary outcome was in-transit critical events, defined by an adaptation of a recent consensus definition. In-transit critical events occurred in 1,094 (12.3%) of 8,889 transports. Hypotension (3.6%), tachycardia (3.7%), and bradycardia (3.3%) were the most common critical events. Crews performed medical interventions in 194 transports (2.2%). The frequency and makeup of critical events varied across patient age groups. Age, pretransport mechanical ventilation, pretransport cardiovascular instability, transport duration, scene calls, and paramedic crew level were independently associated with increased risk of in-transit critical events in multivariate analysis. A Transport Pediatric Early Warning Score of 7 or greater predicted in-transit critical events with high specificity but low sensitivity (92.0% and 20.0%, respectively), but was not superior of the combination of pretransport mechanical ventilation and pretransport cardiovascular instability (sensitivity and specificity of 12.6% and 97.4%, respectively). Removal of early warning signs from the definition resulted in critical event rates comparable to those published in adults and improved predictive performance.
Conclusions: Using new consensus definitions of transport-related critical events, we found critical events occurred in almost one in eight transports, and were strongly associated with pretransport cardiovascular instability. Transport Pediatric Early Warning Score was poorly predictive of in-transit critical events, and was not superior to the presence of pretransport mechanical ventilation and cardiovascular instability. Future prospective studies are required to elucidate the optimal matching of transport resources to patients, in particular those with both pretransport cardiovascular instability and mechanical ventilation.