The current role of decompressive craniectomy in the management of neurological emergencies.

Decompressive craniectomy has been used as a lifesaving procedure for many neurological emergencies, including traumatic brain injury, ischaemic stroke, subarachnoid haemorrhage, cerebrovenous thrombosis, severe intracranial infection, inflammatory demyelination and encephalopathy. The evidence to support using decompressive craniectomy in these situations is, however, limited. Decompressive craniectomy has only been evaluated by randomized controlled trials in traumatic brain injury and ischaemic stroke and, even so, its benefits and risks in these situations remain elusive. If one considers a modified Rankin Scale of 4 or 5 or dependency in daily activity as an unfavourable outcome, decompressive craniectomy is associated with an increased risk of survivors with unfavourable outcome (relative risk [RR] = 2.9, 95% confidence interval [CI] = 1.5-5.8, p = 0.002, I(2 )= 0%; number needed to operate to increase an unfavourable outcome = 3.5, 95% CI = 2.4-7.4), but not the number of survivors with a favourable outcome (RR = 1.5, 95% CI = 0.9-2.6, p = 0.13, I(2 )= 0%).