Acute subdural haematoma in the conscious patient: outcome with initial non-operative management

We have retrospectively reviewed 23 conscious patients, in whom a CT scan diagnosis of acute subdural haematoma was made, and in whom craniotomy for evacuation was not initially performed. These highly selected patients represent 3% of 837 patients with acute subdural haematoma, presenting over a five year, eight month period to the Institute of Neurological Sciences, in Glasgow (1986-1991). Patients with any other associated intracranial abnormalities, such as cerebral contusions, as shown on CT, were excluded from this report. All patients were followed by serial CT scanning, and neurological assessments. Cerebral atrophy was present in over half of the sample. In 17 of our patients, the acute subdural haematoma resolved spontaneously, without evidence of damage to the underlying brain, as shown by CT or neurological findings. Six subsequently required burr hole drainage of a hypodense liquid subdural haematoma. In each of these patients, haematoma thickness was greater than 10 mm. Haematoma volume was significantly larger (53 +/- 6 ml versus 32 +/- 2 ml) in the group who came to operation. The mean delay between injury and operation in this group was 15 days. We conclude that certain conscious patients with small acute subdural haematomas, without mass effect on CT, may be safely managed conservatively.