Intracerebral hematoma after evacuation of chronic extracerebral fluid collections.

Among 140 cases of chronic extracerebral fluid collections treated surgically, 7 cases (5%) of intracerebral hematoma occurring immediately after drainage were encountered. In none of the patients was a preoperative intracerebral clot or contusion identified by either computed tomographic scan or angiography. One patient had pre-existing systemic hypertension. Five of the patients had chronic subdural hematomas, 1 had a subdural hygroma and had been previously radiated for medulloblastoma, and 1 patient had a middle fossa arachnoid cyst. Four of the group had had craniotomies and three had undergone trephination for the primary lesion. The postoperative intracerebral hematomas were manifest by rapid deterioration of consciousness and focal neurological findings occurring usually immediately (but, in 2 cases, a few days after) the original procedure. Five patients underwent secondary craniotomy and 2 had external drainage. Despite rapid treatment, 2 of the patients died, 4 were left with severe disability, and only 1 survived intact. None of the patients had identifiable coagulopathy, and only 1 patient was hypertensive in the immediate postoperative period. The factors that all of the patients had in common were preoperative increased intracranial pressure and shift of the midline structures, as well as rapid surgical decompression of the initial lesion. Possible pathogenic mechanisms include hemorrhage into previously undetected areas of contusion, a sudden increase in cerebral blood flow combined with faulty autoregulation, and damage to parenchymal vessels secondary to rapid intra- or postoperative shift of the intracranial contents. Perhaps this devastating complication can be avoided if closed system drainage is used for the treatment of chronic surface collections.