Or, at least, that’s what the adjusted analysis here wants to suggest – and, by implication, validate using aeromedical transport for patients with traumatic brain injury.
This is a retrospective evaluation of 209,529 TBI patients in the National Trauma Data Bank between 2009 and 2011, comparing ground-based transport to Level I and Level II centers with aeromedical transport to these same centers. Patients flown to Level I and II trauma centers were far more likely to die – in the unadjusted analysis, owing to much higher injury severity scores. Using two methods of adjustment, however, and incorporating propensity score matching, patients with TBI had odds ratios between 1.73 and 1.95 for survival (95% CI 1.55 to 2.10). The adjusted absolute risk reductions for death ranged from 4.69% to 6.37% (95% CI 4.08% to 6.85%).
These are fairly substantial improvements in a reasonably important patient-oriented outcome (mortality). There are, of course, serious limitations in doing this sort of retrospective analysis, making these statistical adjustments, and extrapolating this association out to the presumed benefit of the intervention – that a reduction in trauma response and transport time confers the survival advantage.
This study provides a very low level of evidence moving the needle in favor of aeromedical transport. It’s reasonably clear there are patients that benefit from aeromedical transport – but at $10,000+ per transport, and field over-triage already a problem, this study alone should not inform any change in practice.
“Prehospital Helicopter Transport and Survival of Patients With Traumatic Brain Injury”
http://www.ncbi.nlm.nih.gov/pubmed/24743624