Aneurysmal acute subdural hemorrhage: prognostic factors associated with treatment.

Acute subdural hematoma is an uncommon presentation of aneurysmal hemorrhage that has been identified as a poor prognostic sign. Current series are small, have short follow-up, or were collected over a long period during which treatment evolved. To evaluate prognostic factors, we analyzed a large modern series of aneurysmal subdural hematoma (aSDH) with long-term follow-up. A prospectively maintained database was queried for patients presenting with aSDH from 2001-2013. Thirty patients met the study criteria. Statistical analysis was performed with unpaired t-test or Fisher's exact test. Aneurysm treatment involved open clipping (n=18), endosaccular coiling (n=8), both (n=1), or no treatment (n=3). Good Glasgow Outcome Scale score at discharge was present in 20% and increased to 40% at 6-12 months postoperatively. Good clinical presentation was associated with good final outcome in 75%, whereas poor clinical presentation correlated with good outcome in 30%. Good outcome correlated with younger age (p=0.04), smaller aneurysm (p=0.04), and lower Hunt-Hess score (HH) at intervention (p=0.04). Favorable outcome did not correlate with sex, race, presence of subarachnoid or intraparenchymal hemorrhage, size or laterality of hemorrhage, midline shift, aneurysm treatment modality, or HH at admission (p>0.15). There was no difference between good and poor outcomes in terms of time to treatment or hematoma evacuation. Poor clinical presentation may be exaggerated by mass effect of hematoma; aggressive treatment is not futile. Presenting neurological status, age, and aneurysm size are predictors of outcome, while laterality and size of hematoma and extent of midline shift are not, suggesting that clinical status is more important than radiographic findings.