External Ventricular Drains and Mortality in Patients with Severe Traumatic Brain Injury

Purpose: To determine our institutional adherence to the Brain Trauma Foundation guidelines with respect to intracranial pressure (ICP) monitoring, and examine the relationship between external ventricular drain (EVD) use and mortality. Materials & Methods: Retrospective cohort study of 171 patients with severe traumatic brain injury (TBI). Propensity score adjusted logistic regression was used to model the association between EVD use and mortality. Results: EVDs were inserted in 98 of 171 patients. Of the 73 patients without an EVD, 63 (86%) would have qualified for ICP monitoring under the current guidelines. EVDs were in situ for a median of 8 days (SD 6). In adjusted analyses, EVD use was associated with hospital mortality (OR 2.8, 95% CI: 1.1 - 7.1, p=0.04) and 28-day mortality (OR 2.1, 95% CI: 0.80 - 5.6, p=0.13). We observed significant modification of the association between EVD and 28-day mortality by GCS within 12 hours (p-interaction = 0.04), indicating strong association only among those patients with GCS score of at least 6 (OR 5.0, 95% CI: 1.5 - 16.7, p<0.01). Conclusions: The association of EVD with 28-day mortality was only apparent among patients with GCS score of >= 6. Further research is warranted to further refine which patients may benefit from ICP monitoring.