There continues to be a considerable interest in
decompressive craniectomy in the management of severe
traumatic brain injury (TBI). Though technically straightforward, the procedure is not without significant complications. In this study we assessed the incidence and risk factors for the development of
subdural hygroma and
hydrocephalus after
decompressive craniectomy. A total of 195 patients who had had a
decompressive craniectomy for severe TBI between 2004 and 2010 at the two major trauma centers in Western Australia were considered. Of the 166 patients who survived after the acute
hospital stay, 93 (56%; 95% confidence interval [CI] 48,63%) developed
subdural hygroma; 45 patients (48%) had unilateral and 48 patients (52%) had bilateral subdural
hygromas. Of the 159 patients who survived more than 6 months after surgery, 72 (45%; 95% CI 38,53%) developed radiological evidence of ventriculomegaly, and 26 of these 72 patients (36%; 95% CI 26,48%) developed clinical evidence of
hydrocephalus and required a ventriculoperitoneal (VP) shunt. Maximum intracranial pressure prior to
decompression (p=0.005),
subdural hygroma (p=0.012), and a lower admission Glasgow Coma Scale score (p=0.009), were significant risk factors for
hydrocephalus after
decompressive craniectomy.
Hydrocephalus requiring a VP shunt was associated with a higher risk of unfavorable neurological outcomes at 18 months (odds ratio 7.46; 95%CI 1.17,47.4; p=0.033), after adjusting for other factors. Our results showed a clear association between injury severity,
subdural hygroma, and
hydrocephalus, suggesting that damage to the
cerebrospinal fluid drainage pathways contributes to the primary
brain injury rather than the margin of the
craniectomy as the factor responsible for these complications.