Yesterday, Today & Tomorrow: Best Practice for CSF Sampling of an EVD to Minimise Patient Risk

Abstract

Managing raised intracranial pressure (ICP) with the use of an external ventricular drain (EVD) is a common occurrence in a neurosurgical setting. A central role of the neuroscience nurse in managing that EVD is to monitor the patient for signs and symptoms of infection otherwise known as ventriculitis. Cerebrospinal fluid (CSF) sampling from an EVD has historically been completed as a daily routine specimen to monitor for any signs of infection. However, in more recent times there has been evidence to suggest that specimens should only be collected when infection or ventriculitis is suspected to minimise the interruption of the closed system. Different practices have been identified related to the frequency of sampling, the best solution for decontamination of the sampling site/ port and preferable port for obtaining the specimen. Our aim was to complete an integrative literature review. Medline Complete and CINAHL were searched and articles were screened. Nine articles were used to form the integrated review. The main findings were collated and found that daily sampling is no longer recommended. The proximal port was the most popular choice for sampling. Decontaminating solutions used for accessing an EVD varied with no evidence to support the choice of solution. Findings of the majority of papers were focussed on sampling frequency and other associated ways to minimise infection rather than choice of sampling site or the use of specific decontaminating solutions.

Cerebrospinal fluid white cell count to red cell count ratio as a predictor of ventriculitis in patients with external ventricular drains

“…25 Despite this, to the authors' knowledge, no study exists which defines an exact frequency of sampling to reduce infections while accurately screening for infection. 7 A proposed regimen of routine sampling every 3 days, with additional samples taken when clinical suspicion for ventriculitis remains high, has been reported 26 and is practiced at our unit. Our sample supports this conclusion, with an increase in the frequency of sampling demonstrating statistical association with the rate of infection.…”

Does duration and sampling of external ventricular drainage systems influence infection rate?

“…CSF samples are collected routinely from EVD systems for laboratory tests. There have been several studies conducted that discuss the correlation between sampling and infection rate (Crane & King, 2015). However, there have been few studies conducted to identify the most appropriate site for cerebrospinal fluid collection in order to reduce the disruption of the closed EVD system and reduce the risk of infection.…”

“…However, there have been few studies conducted to identify the most appropriate site for cerebrospinal fluid collection in order to reduce the disruption of the closed EVD system and reduce the risk of infection. It is also controversial whether regular changes of EVDs can reduce CSF infection (Crane & King, 2015;Wong, 2011).…”