Analysis of Disease-Specific Outcomes According to Time of Doctor Helicopter Dispatch Request

To evaluate whether the keyword method-requesting the dispatch of a doctor helicopter (DH) based on information obtained from the emergency call before emergency medical technicians make contact with patients-is useful for other disease category, using data from the Japan DH Registry (JDHR).

Patients (N = 41,592) enrolled in JDHR were included in the study. The following data were collected for each subject: time from emergency call to DH staff-patient contact, DH request method (keyword or not), gender, age, vital signs at the time of emergency medical technician contact, medical intervention details, disease category details which were determined by the JDHR classification, hospitalization duration, and 1-month outcome. The subjects were dichotomized into the following 2 groups in each disease category: a keyword group and a control group.

The study revealed significant disparities of the backgrounds between the 2 groups in each disease category. The keyword group had statistically significant earlier patient contact, respectively, in each disease category, compared with the control group. Concerning the overall performance category in 1 month, the keyword group exhibited low values (favorable function) of cerebral infarction, intracerebral hemorrhage, other endogenous diseases, and trauma category compared with the control group. The keyword group exhibited a statistically significant shorter hospital stay in other endogenous diseases, trauma, and non-trauma cases of exogenous diseases. Multivariate analysis revealed that the keyword method was not selected as an independent factor related to survival, except in the intracerebral hemorrhage category.

In our study, early DH involvement dispatch and rapid transport by keyword methods were associated with better outcomes or shorter hospital stay, regardless of heterogeneity in patient characteristics and disease types. However, the keyword-based dispatch system itself did not seem to improve outcomes independent of patient-specific factors and disease severity.