Treatment: ETV & Other Procedures
External ventricular drain (EVD)
An external ventricular drain is a temporary catheter that drains cerebrospinal fluid from a ventricle to an external collection system, used in urgent or short-term situations.
In short: External ventricular drain (EVD)
- It temporarily drains CSF from a ventricle to outside the body.
- It is used in urgent or short-term situations.
- It allows pressure monitoring and CSF drainage.
- It is a temporary measure, not a permanent solution.
What it is
An external ventricular drain (EVD) is a temporary catheter placed into a ventricle and connected to an external collection system, draining cerebrospinal fluid out of the body. It is used in urgent or short-term situations to relieve pressure and drain CSF.
Understanding External ventricular drain (EVD)
An EVD is often placed in emergencies or critical settings — for example, in acute hydrocephalus, after a severe hemorrhage, or temporarily during the management of an infection — to drain CSF and control pressure. It also allows direct measurement of intracranial pressure and sampling of CSF. Because it connects to an external system, the amount of drainage can be precisely controlled, but the EVD is a temporary measure: it requires the person to remain in the hospital, carries a risk of infection over time, and is eventually removed or replaced by a permanent solution (such as a shunt or ETV) if ongoing CSF diversion is needed. The EVD is a key tool for urgent, controllable CSF drainage.
Why it matters
Understanding the EVD helps families see how CSF can be drained urgently and controllably in critical situations, while recognizing it is a temporary measure that is eventually removed or replaced if long-term diversion is needed.
Common questions
What is an external ventricular drain?
A temporary catheter draining CSF from a ventricle to outside the body.
When is it used?
In urgent or short-term situations.
Is it permanent?
No — it is temporary and is removed or replaced by a permanent solution if needed.
Bottom line
An external ventricular drain temporarily drains CSF from a ventricle externally in urgent situations, allowing pressure control until a permanent solution if needed.
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