External ventricular drain infection: improved technique can reduce infection rates.

INTRODUCTION: The placement of external ventricular drain (EVD) is a common neurosurgical procedure to drain cerebrospinal fluid (CSF) in many acute neurosurgical conditions that disrupt the normal CSF absorption pathway. Infection is the primary complication with infection rates ranging between 0% and 45%, and this is associated with significant morbidity and mortality, prolonged hospital stay and increased hospital costs.This article compares and discusses the differences in rates of EVD CSF infection between clinical neurosurgical practice and the infection rates in a group of research patients where EVDs were sampled frequently as part of the study.

MATERIALS AND METHODS: Patients who had EVD placed were identified by review of theatre logs from 2005-2008. A retrospective case-note review was performed with the primary end point being those patients treated with intrathecal antibiotics. Patients within the research group were identified from established data and the same primary endpoint was used. A standard silicone catheter was the EVD used in both cohorts. Patients were excluded if the EVD was placed for diagnoses other than hydrocephalus associated with aneurysmal subarachnoid haemorrhage (SAH).

RESULTS: Ninety-four patients had 156 EVDs placed within the clinical group, 49 patients were treated giving an infection rate within this group of 52.1% per patient and 31.4% per EVD. Thirty-nine patients had 39 EVDs placed within the research group, four patients were treated, the infection rate within this group was 10.3% per EVD, p = 0.0001.

CONCLUSION: Sampling or irrigating ventricular drainage systems does not increase the risk of CNS infection providing the operator has appropriate experience and has used theatre standard aseptic technique.