Prevalence and Predictors of Under-Diversion in the Primary Trauma Diversion System in Hong Kong

Abstract

Introduction Primary trauma diversion (PTD) enables direct transfer of major trauma patients to trauma centres for definitive care. This study aimed to evaluate the performance of PTD in the New Territories West Cluster (NTWC) of Hospital Authority and to identify the predictors for under-diversion. Methods A cross-sectional study based on local trauma registry. All major trauma patients (defined as ISS>15 or requiring trauma team activation) in the catchment area of the local hospital from September 2007 to December 2011 were included. The appropriateness of diversion decision was independently evaluated by an expert team (a trauma nurse coordinator and an emergency medicine practitioner). The sensitivity, specificity, predictive values, agreement, over-diversion and under-diversion rates were calculated. Potential predictors for under-diversion including age, Glasgow Coma Scale, mechanism of injury, injured body part, and the distance from scene to the trauma centre/local hospital were employed for logistic regression analysis. Results There were 141 eligible cases identified. The sensitivity and specificity for PTD were 59.5% and 96.5% respectively. The over-diversion rate was 3.5% and the under-diversion rate was 40.5%. The overall accuracy was around 74.5%. Non-motor vehicle accident (OR 13, 95% confidence interval [CI]=3.5-48.0, p<0.01) and isolated head injury (OR 5.35, 95% CI=1.5-19.5, p=0.01) were 2 independent predictors for under-diversion in PTD. Conclusions The overall field triage compliance by the paramedics is satisfactory. Under-diversion rate in NTWC is high. Non-motor vehicle accident mechanism and isolated head injury are 2 significant predictors for under-diversion. Reinforcement in training to avoid potential pitfalls would improve the paramedics' trauma triage performance.