External Ventricular Drainage: A Practical Guide for Neuro-Anesthesiologists

External ventricular drainage is often considered a life-saving treatment in acute hydrocephalus. Given the large number of discussion points, the ideal management of EVD has not been completely clarified. The objective of this study was to review the most relevant scientific evidence about the management of EVD in its main clinical scenarios. We reviewed the most recent and relevant articles about indications, timing, management, and complications of EVD in neurocritical care, with particular interest in patients with subarachnoid hemorrhage (SAH), severe traumatic brain injury (TBI), and intraventricular hemorrhage (IVH) using the following keywords alone or matching with one another: intracranial pressure, subarachnoid hemorrhage, traumatic brain injury, intraventricular hemorrhage, external ventricular drainage, cerebrospinal shunt, intracranial pressure monitoring, and ventriculoperitoneal shunt. In the management of EVD in SAH, the intermittent drainage strategy is burdened with an elevated risk of complications (e.g., clogged catheter, hemorrhage, and need for replacement). There seems to be more ventriculoperitoneal shunt dependency in rapid weaning approach-managed patients than in those treated with the gradual weaning approach. Although there is no evidence in favor of either strategy, it is conventionally accepted to adopt a continuous drainage approach in TBI patients. Less scientific evidence is available in the literature regarding the management of EVD in patients with severe TBI and intraparenchymal/intraventricular hemorrhage. EVD placement is a necessary treatment in several clinical scenarios. However, further randomized clinical trials are needed to clarify precisely how EVD should be managed in different clinical scenarios.