SURGICAL OUTCOME OF CHRONIC SUBDURAL HAEMATOMA: A 5‐YEAR AUDIT *

Chronic subdural haematoma (CSDH) is a common neurosurgical condition that has been studied extensively.1–3 Unlike acute post‐traumatic subdural haematoma, there is often minimal associated parenchymal brain injury with CSDH and surgical outcome is satisfactory in most cases. However, the fact that CSDH affects primarily elderly people means that operative mortality and morbidity is by no means uncommon.4,5 In this review, we report the surgical outcome of CSDH at a local neurosurgical centre over the course of 5 years, with emphasis on treatment‐related morbidity and mortality.A retrospective analysis was performed on 108 patients who underwent operation for CSDH at Queen Mary Hospital, Hong Kong, between January 1995 and December 1999. The diagnosis of CSDH was made on computerized tomography (CT) in all cases and confirmed at operation. Patients with acute post‐traumatic subdural haematoma and subdural effusion were excluded.There were 108 patients. The male to female ratio was 3 : 1. The mean age was 73 years. The majority of patients presented with limb weakness. History of head injury could be identified with certainty in less than half of the patients. Eight patients had bleeding tendency who required delayed operations—six were taking salicylate, one was taking ticlopidine and one was on warfarin.Two patients underwent craniotomy—one for a heavily loculated CSDH and the other had a solid mass of organized CSDH. Both recovered uneventfully. For those who underwent burr hole drainage, more than half did not have any postoperative drainage.One 55‐year‐old female developed subdural empyema. One 64‐year‐old male suffered from postoperative tonic‐clonic seizure. There were five recollections of haematoma which required re‐operations. There were four deaths, giving rise to a hospital mortality rate of 4%.This series is an audit of the surgical outcome of chronic subdural haematoma at a local neurosurgical centre and shows that the mortality and morbidity rates are compatible with current standard of care. The nature of a retrospective study is such that detailed assessment of postoperative clinical and functional improvement is severely hampered by suboptimal documentation and recall bias. It is hoped that a prospective study in the near future will revisit the issue in more positive light.