Prognosis of aneurysmal subarachnoid hemorrhage not altered by transatlantic air transfer. A matched case-control study

BackgroundThe treatment of a ruptured aneurysm, in a center with expertise in aneurysmal subarachnoid hemorrhage (aSAH), is recommended preferably within 24 to 72 hr. We assessed the impact of long-distance aeromedical evacuation in patients presenting aSAH in a remote island without neuro-interventional capacities. MethodsThis was a case-control study of patients with aSAH flown from a French Caribbean island (Guadeloupe) to Paris, France (6750 km), for neuro-interventional and neuro-ICU management and identical patients from the Paris region over a 10-year period (2010 to 2019). The two populations were matched on age, sex, World Federation of Neurological Surgeons score, and Fisher score. The primary outcome was the 1-year modified Rankin Scale (mRS) score divided into two categories: good outcome (mRS 0 to 3) and poor outcome (mRS 4 to 6). A cost study was added. ResultsAmong 128 consecutive aSAH transferred from Guadeloupe, 93 could be matched with 93 patients with aSAH from the Paris area. The median [Q1,Q3] time from diagnosis to securing the aneurysm was 48 hr [30,63] in the Guadeloupe group versus 23 [12,24] in the control group (p<0.001). The rate of good clinical outcome (1-year-mRS [&le;] 3) was 75% in the Guadeloupe group and 82% in the control group (p=0.1). The groups did not differ in 1-year mortality (18% vs 14%, p=0.5) and duration of mechanical ventilation. However, Guadeloupe patients more frequently required mechanical ventilation (59% vs 38%, p<0.001) and external ventricular drainage (55% versus 39%, p=0.005) than the control group, although the number of hydrocephalus events did not differ. The additional cost of treating a Guadeloupe patient in mainland France was estimated at 7580 euros, or 17% of the estimated cost in Guadeloupe. ConclusionsLong distance aeromedical evacuation of Guadeloupe patients with aSAH resulted in a 25-hr increase in median embolization time but had no effect on mortality or functional prognosis at 1 year.