Clinical Characteristics and Predictors of Delayed Cerebral Ischemia in High-Altitude Aneurysmal Subarachnoid Hemorrhage

The study examined aneurysmal subarachnoid hemorrhage (aSAH) in 256 patients at a Tibetan neurosurgical center at altitudes of 2,330 to 4,920 meters between 2013 and 2015. Delayed cerebral ischemia (DCI), the most feared complication of aSAH, developed in 26 patients (10.2%). Hospital mortality was 1.6%, and most patients presented in good condition (Hunt-Hess I-II in 73% of cases). Analysis showed that only Fisher grade was an independent predictor of DCI, while altitude and hemoglobin were not associated with DCI risk. The predictive model achieved an area under the curve of 0.812. At one-year follow-up, 77.8% of patients achieved favorable functional outcomes. The study concluded that prognostic frameworks from sea level remain valid at high altitude.