Background: Many patients will experience progression of stroke symptoms and deteriorate on route prior to first assessment in the emergency department (ED); others may deteriorate early in the ED course prior to establishment of final diagnosis. We describe the early clinical course among hyperactue stroke patients evaluated by paramedics <2 hours from symptom onset.
Methods: We analyzed patients in the NIH Phase 3 Field Administration of Stroke Therapy - Magnesium (FAST-MAG) multi-ambulance, multihospital trial enrolling prehospital acute stroke patients ≤2 hours from last known well. Three serial Glasgow Coma Scale (GCS) exams were performed: 1) in the field by at enrollment; 2) immediately upon ED arrival by ED staff; and 3)early post-arrival by trained study nurses. Clinical deterioration (CD) was defined as a 2-point deterioration in GCS from the prior exam.
Results: Among the 962 patients, meeting study criteria, mean age was 69 (SD13) years, 42% female, 24% Hispanic ethnicity, 79% white, 12% Black, 8% Asian, with final diagnosis of cerebral ischemia in 713 (74%), intracranial hemorrhage in 213 (22%) and mimic in 40 (4%). Median time from last known well to initial paramedic GCS was 23 mins (IQR 14-42), to ED arrival GCS 45.5 mins (37-50) and to early post-arrival GCS 150 mins (120-180). Overall, neurologic deterioration in 166/962 (17.3%), including 60 (6.2%) with deterioration only in the prehospital period, 59 (5.1%) with deterioration only in the early post-arrival period, and 57 (5.9%) with deterioration in both.
Factors associated with prehospital CD were ICH diagnosis,23% vs. 9%, p<0.001,) and lower prehospital GCS, 14 (IQR 12-15) vs. 15( IQR 15-15), p<0.001. Factors associated with post-arrival CD included ICH diagnosis (24% vs. 7%, P<0.001and prehospital deterioration (20% vs. 10%, p=0.001). Age, gender, race and ethnicity were not associated with deterioration.
Conclusions: Stroke progression is common in the hyperacute period, both prior to ED arrival and early after arrival. Intracranial hemorrhage causes neurologic deterioration 2-3 times as frequently as acute cerebral ischemia, both before and soon after ED arrival.