Prehospital Glasgow Coma Score Predicts Emergent Intervention following Helicopter Transfer for Spontaneous Subarachnoid Hemorrhage.

BACKGROUND: Helicopter transport may shorten transport time to neurosurgical intervention; however, there are few data regarding its utility for nontraumatic emergencies.

METHODS: Prehospital and hospital records of all patients transferred via helicopter to Dartmouth-Hitchcock Medical Center for spontaneous subarachnoid hemorrhage between January 2007 and December 2011 were reviewed. Primary outcome measure was emergent tertiary-level care intervention, defined as ventriculostomy, conventional angiography, endovascular treatment, or craniotomy within 3 hours of arrival.

RESULTS: Fifty-one patients met inclusion criteria. Median helicopter transport time, defined as time from telephone referral to arrival, was 97 minutes (range, 61-214 minutes). Fifteen patients underwent intervention within 3 hours of arrival (29%), 19 patients underwent intervention between 3 and 6 hours (37%), 9 patients underwent intervention between 6 to 12 hours (18%), and 11 patients underwent intervention greater than 12 hours after arrival (16%). Univariate analysis of pretransfer clinical and radiographic findings showed significant correlations between Glasgow Coma Scale (GCS) score less than 15 (odds ratio [OR], 22.8; 95% confidence interval [CI], 4.2-122.5), World Federation of Neurologic Surgeons (WFNS) scale greater than 2 (OR, 46.75; 95% CI, 7.511-290.99), presence of intraparenchymal hemorrhage (OR, 4.7; 95% CI, 1.3-17.5), and intubation (OR, 12.4; 95% CI, 2.9-51.8) with emergent intervention. On logistic multivariate regression analysis, GCS score less than 15 and WFNS scale score greater than 2 independently predicted emergent intervention.

CONCLUSIONS: A majority of patients with spontaneous subarachnoid hemorrhage who were transferred by interfacility helicopter ambulance did not require emergent intervention. GCS score less than 15 at an outside hospital was independently associated with emergent intervention on multivariate analysis.