Introduction: External ventricular drains (EVDs) have an important role in the management of neurological disease and are one of the most common neurosurgical procedures. Hemorrhage is a common complication of EVD placement and has recently been recognized to occur more frequently than originally believed. There is also risk of hemorrhage with removal of an EVD, which has not been well described. We investigated the risk factors associated with placement and removal of EVDs at our institution.
Methods: After obtaining IRB approval, a database was created to include all patients who required EVD placement from March 2008 to June 2014 at our institution. A retrospective chart review was completed and all imaging studies during the index hospitalization were reviewed for evidence of hemorrhage on placement and removal of an EVD.
Results: 482 EVDs were placed in 380 patients during the designated time period for hemorrhage (213), tumor (86), shunt infection or malfunction (57), hydrocephalus (48), cerebral edema (17), trauma (8), and other causes (53). Hemorrhage occurred in 94 patients (19.5%) on EVD placement. The hemorrhage volume ranged from 0.003cm3 to 45.9cm3 and the average was 1.96 ± 6.48cm3. Fifty-five EVDs (22.5%) were associated with a hemorrhage on EVD removal. The average volume was 8.25 ± 20.34cm3 and the hemorrhage volumes ranged from 0.012cm3 to 82.08cm3.
Conclusions: Multiple studies have investigated hemorrhage related to EVD placement with rates varying from 0-42%, while very few studies have described hemorrhage secondary to EVD removal. This is the first reported analysis of risk factors associated with hemorrhage on EVD removal. In this series of patients, decreased platelet count on admission and an increasing number of attempts for placement correlated with an increased risk of hemorrhage on EVD placement. Only those with an EVD placed at beside were more likely to have hemorrhage on EVD removal.
Patient Care: Identifying factors associated with procedural complications can allow us to accurately evaluate the risks and benefits of EVD procedures and potentially decreasing the likelihood of these complications.
Learning Objectives: By the conclusion of this session, participants should be able to 1) Recognize the risk factors associated with EVD placement and removal, 2) Discuss in small groups the possible mechanisms for these hemorrhages