Literature Review: Undertriage by Age Group

Nakamura Y, Daya M, Bulger EM, et al. Evaluating age in the field triage of injured persons. Ann Emerg Med 2012, May 24 [e-pub ahead of print].

Abstract

[Authors] evaluate trauma undertriage by age group, the association between age and serious injury after accounting for other field triage criteria and confounders, and the potential effect of a mandatory age triage criterion for field triage. Methods—This was a retrospective cohort study of injured children and adults transported by 48 EMS agencies to 105 hospitals in 6 regions of the western United States from 2006 through 2008. [Authors] used probabilistic linkage to match EMS records to hospital records, including trauma registries, state discharge databases and emergency department databases. The primary outcome measure was serious injury, as measured by an Injury Severity Score (ISS) greater than 15. [Authors] assessed undertriage (ISS greater than 15 and triage-negative or transport to a nontrauma center) by age decile and used multivariable logistic regression models to estimate the association between age and ISS greater than 15, adjusted for important confounders.

Results—Injured patients (260,027) were evaluated and transported by EMS during the 3-year study period. Undertriage increased for patients older than 60, reaching approximately 60% for those older than 90. There was a strong nonlinear association between age and ISS greater than 15. For patients not meeting other triage criteria, the probability of serious injury was most notable after age 60. A mandatory age triage criterion would have decreased undertriage at the expense of overtriage, with 1 patient with ISS greater than 15 identified for every 60–65 additional patients transported to major trauma centers. Conclusion—Trauma undertriage increases in patients older than 60 years. Although the probability of serious injury increases among triage-negative patients with increasing age, the use of a mandatory age triage criterion appears inefficient for improving field triage.

Comment

It is well established that trauma centers are better equipped to care for our more seriously injured patients and that one of the critical roles of EMS is to accurately identify those patients. The CDC trauma triage guidelines list “age greater than 55” as one of their “special patient considerations.” This study looked at whether a strict rule of “age greater than 60 = trauma center” would improve triage accuracy. What its authors found was not surprising: Only 1 in 60 of the new “mandatory” patients was seriously injured. Most of our systems rely heavily (and appropriately) on EMS provider judgment to sort out seriously injured from non-seriously injured patients. This study would support that approach. EMS providers need to consider age as one of their criteria and have a lower threshold for transporting older individuals to trauma centers (and the older the patient, the lower the bar), but a simple rule of “everyone older than 60 to a trauma center” does not work.

Angelo Salvucci, Jr., MD, FACEP, is medical director for the Santa Barbara County and Ventura County (CA) EMS agencies and a member of the EMS World editorial advisory board.