WE7.9 Triage in Terror-Related Major Incidents

Introduction Recent major incidents (MI) in the UK have involved intentional explosions or indiscriminate attacks by perpetrators with bladed weapons. At a MI, on-scene triage vitally identifies those needing time-critical surgery and/or resuscitation (Priority 1, or P1, casualties), facilitating urgent transfer to specialist care. Currently, the National Ambulance Resilience Unit (NARU) Triage Sieve is used. We interrogated the Trauma Audit and Research Network (TARN) registry to compare performance of MI triage tools in predicting P1 status amongst adults. Methods TARN patients aged ≥16 years with penetrating and blast injury (January 2008-December 2017) were assigned triage categories (P1, P2, P3, Expectant or Dead) using pre-defined, intervention-based criteria. Ten MI triage tools were applied to patients’ first pre-hospital observations. Tool-predicted and intervention-based P1 assignments were compared. Results Of 5,660 patients, 5,635 (92%) suffered penetrating injuries, 25 (0.4%) sustained blast injuries. Mortality was 3.1% (n=171); median Injury Severity Score was 9 (IQR 9–16). 2,639 (46.6%) patients fulfilled P1 criteria: 1,170 (44.3%) required life-saving and 209 (7.9%) required limb-salvage surgery within 4 hours. The NARU Triage Sieve demonstrated sensitivity of 32.2%, over-triage 40.3% and AUC 0.566 (95%CI 0.555–0.578). The tool best-able to identify P1 casualties was the Battlefield Casualty Drills (BCD) Triage Sieve (sensitivity 68.0%, over-triage 47.3%, AUC 0.573 [95%CI 0.561–0.586]). Conclusions Terrorist attacks characteristically yield a high proportion of patients requiring urgent surgery. The current UK MI triage tool in use, the NARU Triage Sieve, exhibits unacceptably low detection of P1 casualties; we recommend it is superseded by the BCD Triage Sieve.