What is the purpose of EVD?
External ventricular drain (EVD): A temporary system that allows drainage of cerebral spinal fluid (CSF) from the ventricles to an external closed system.
How does EVD drain work?
An external ventricular drainage (EVD) system drains CSF by using a combination of gravity and intercerebral pressure. The drainage rate depends on the height at which the EVD system is placed relative to the patient’s anatomy.
Why do you raise EVD?
For a patient with SAH and an unsecured aneurysm it is important to set the initial height of the EVD “high” so that CSF is not drained too quickly to avoid a rapid change in transmural pressure across the aneurysm wall which may lead to re-bleeding.
Why do you need a lumbar drain?
A lumbar drain is often needed to collect CSF from the spine after surgery or to reduce pressure in the spinal cord or brain. Too much pressure in the spinal cord can slow blood flow to the area and can lead to confusion and trouble thinking, pain, weakness, and even paralysis.
Is EVD serious?
EVD application is frequently complicated by misplacement, hemorrhage, dislodgement, blockage, and most importantly infection (6). EVD infection rate ranges from 0 to 22% (7–9) resulting in a significant increase in cost, hospital stay, morbidity, and mortality (6, 10).
What is an external ventricular drain (EVD)?
(October 2017) An external ventricular drain (EVD), also known as a ventriculostomy or extraventricular drain, is a device used in neurosurgery to treat hydrocephalus and relieve elevated intracranial pressure when the normal flow of cerebrospinal fluid (CSF) inside the brain is obstructed.
Can an EVD dislodge the tip of the drain?
However, it is possible for the EVD to dislodge or migrate. This will cause the tip of the drain to migrate away from its intended position and provide inaccurate ICP measurement or lead to occlusion of the drain. The EVD is a foreign body inserted into the brain, and as such it represents a potential portal for serious infection.
What is the role of EVD in the intensive care unit?
Insertion of an external ventricular drain (EVD) is arguably one of the most common and most important lifesaving procedures encountered in the neurologic intensive care unit.[5]
What is the role of external ventricular drain in head injury?
CSF drainage via an external ventricular drain (EVD) or ventriculostomy is a highly effective and physiologic method of ICP reduction in head-injured patients. The utility of the ventriculostomy catheter, however, may be compromised in the presence of considerable brain edema and subsequent ventricular collapse.