Evaluation of the New South Wales ambulance T1 major trauma transport protocol: A state-wide data linkage study.

INTRODUCTION: Prehospital triage and transport protocols are critical components of the trauma systems. Still, there have been limited studies evaluating the performance of trauma protocols in New South Wales, such as the NSW ambulance major Trauma transport protocol (T1).

OBJECTIVES: Determine the performance of a major trauma transport protocol in a cohort of ambulance road transports METHODS: A data-linkage study using routine ambulance and hospital datasets across New South Wales Australia. Adult patients (age > 16 years) where any trauma protocol was indicated by paramedic crews and transported to any emergency department in the state were included. Major injury outcome was defined as an Injury Severity Score >8 based on coded in-patient diagnoses, or admission to intensive care unit or death within 30 days due to injury. Multivariable logistic regression was used to determine ambulance predictors of major injury outcome.

RESULTS: There were 168,452 linked ambulance transports analysed. Of the 9,012 T1 protocol activations, 2,443 cases had major injury [positive predictive value (PPV) = 27.1%]. There were 16,823 major injuries in total giving a sensitivity of the T1 protocol of 2,443/16,823 (14.5%), specificity of 145,060/151,629 (95.7%) and a negative predictive value (NPV) of 145,060/159,440 (91%). Overtriage rate associated with T1 protocol was 5,697/9,012 (63.2%) and undertriage rate was 5,509/159,440 (3.5%). The most important predictor of major injury was the activation of more than one trauma protocol by ambulance paramedics.

DISCUSSION: Overall, the T1 was associated with low undertriage and high specificity. The protocol may be improved by considering age and the number of trauma protocols activated by paramedics for any given patient.