Risk factors for infections related to external ventricular drainage

Abstract

BACKGROUND External ventricular drainage (EVD) is the most common method of treatment for patients with increased intracranial pressure due to acute hydrocephalus. The most frequent complications of EVD are infections of the central nervous system. Earlier studies indicated numerous risk factors, although the results of studies regarding the impacts of individual factors on the occurrence of infections differ. Our research was aimed at finding the risk factors for infection in patients with an inserted EVD, treated at the Department of Neurosurgery of University Medical Centre (UMC) Ljubljana. METHODS In the article we describe a retrospective research of EVDs inserted in the period from January 2000 to January 2009. Forty-eight cases of EVDs met the study inclusion criteria. Among them, there were 10 cases with an infection which occurred during inserted EVD. We recorded, compared and evaluated information about the patient, the EVD and infections. RESULTS The duration of the drainage was confirmed as a risk factor for EVD infections (p = 0.004). The infection occurred on average on day 8.9 ± 5.4. The shares of subarachnoid and intraventricular hemorrhage, previous neurosurgical procedures, EVD manipulations, number of successive drainages and duration of hospitalization were greater in the cases of infected EVDs. In the cases of EVD exchange, the average day of change in group without infection was day 10.9 ± 5.8 (p = 0.030). Among infectious agents, Gram-positive bacteria prevailed. CONCLUSIONS Strict asepsis is advised during insertion and handling of EVD and a prophylactic exchange of EVD on day 10 of insertion. Risk factors in our study do not differ from findings in other studies. Therefore it is suggested that prophylactic measures against drain-related infection should be developed and implemented and their efficacy confirmed in a prospective study.