Mobile Stroke Unit Site Experience in Diagnosis and Management of Extraparenchymal Intracranial Hemorrhage in the Prehospital Setting.

Background: Mobile stroke units (MSUs) permit advanced cerebrovascular diagnosis, triage, and treatment to be delivered in the field. While the range of acute cerebral ischemia and intraparenchymal hemorrhage patients encountered by MSUs has been described, the frequency, determinants, and outcomes of patients presenting with extraparenchymal intracranial hemorrhages (subdurals/subarachnoid/epidural) has not been well delineated. Methods: We analyzed consecutive transports among MSU programs in 3 cites, Los Angeles, Houston and Cleveland from program inception through August 2018 in the two former and through 2015 in the latter. Frequency and demographic, presenting, and treatment features of patients with subdural hematoma (SDH) and subarachnoid hemorrhage (SAH) were quantified. Results: Among 850 overall transports, extraparenchymal intracranial hemorrhages accounted for 18 (2.1%), and included 11 (1.3%) SDH and 7 (0.8%) SAH. Among the SDH patients, age was mean 70/median 77 (range 28 to 85). Special features of SDH cases included: acute on chronic blood on CT in 36%, seizures in 9%, and isolated head trauma in 9%. Among SAH patients, mean age was 57 (range 41-75). Special features of SDH/SAH cases included accompanying intraparenchymal hemorrhage in 17%. Of the 18 combined SDH/SAH patients (67% women), 4 (22%) required field intubation, 1 (5%) was actively treated in the field with KCentra to reverse anticoagulation, and 5 (28%) were treated in the field with antihypertensives. (See Figure for exemplar cases.) Conclusions: Extraparenchymal intracranial hemorrhages account for about 1 in 50 cases managed in Mobile Stroke Units. MSU response permits immediate definitive diagnosis by CT imaging, earlier start of indicated medical therapies, and direct routing to neurosurgically-capable stroke centers.