Diagnosis-specific patterns for direct ED discharge after physician-staffed HEMS transport in Japan: A nationwide registry study.

INTRODUCTION

A proportion of patients transported by helicopter emergency medical services (HEMS) are directly discharged from the emergency department (ED). However, nationwide diagnosis-specific patterns of direct ED discharge after HEMS transport remain unclear.

METHODS

This retrospective study analyzed patients transported from the scene by physician-staffed HEMS in Japan (April 2020-March 2023). The primary outcome was direct ED discharge. Mixed-effects logistic regression with a prefecture-level random intercept was performed to explore associations between demographic, clinical, and dispatch factors at first contact and direct ED discharge for trauma and non-trauma patients.

RESULTS

Of 28,213 patients, direct discharge occurred in 11.7% (1445/12,321) of trauma and 14.9% (2371/15,892) of non-trauma patients. Among trauma patients, direct discharge was frequent when the main injury involved the upper extremities but uncommon for truncal injuries (abdomen and pelvis). Among non-trauma patients, direct discharge was rare in the cardiac, cerebrovascular, respiratory, and digestive diagnostic categories, but frequent in the mental and behavioral, musculoskeletal, and symptom/sign categories. Younger age, female sex, pre-arrival HEMS activation, and a higher Glasgow coma scale score were associated with a higher likelihood of direct discharge in both trauma and non-trauma patients. Higher systolic blood pressure was associated with direct discharge in trauma patients, while lower values were associated with it in non-trauma patients

CONCLUSION

The proportion of direct ED discharge after physician-staffed HEMS transport varied substantially across diagnostic categories in both trauma and non-trauma patients. This pattern may partly reflect diagnostic uncertainty in the initial assessment at first contact by the HEMS physician.