External ventricular drain insertion

Why are we operating?

A catheter into the lateral ventricle through a frontal burr hole at Kocher's point: the emergency treatment of hydrocephalus and raised intracranial pressure, and the ICU's window on the pressure itself.

Indication: Acute hydrocephalus (haemorrhage, tumour, infection), refractory intracranial hypertension needing CSF drainage, and pressure monitoring with a therapeutic option attached.

The operation in 4 steps

1. 01Kocher's point

   The entry is marked about 11 cm back from the nasion and 3 cm from the midline, at the mid-pupillary line, in front of the coronal suture on the non-dominant side where possible.

2. 02Burr hole and dural opening

   A small scalp incision, a burr hole through both tables of the skull, and a cruciate opening of the dura just wide enough for the catheter.

3. 03Ventricular cannulation

   The catheter is passed perpendicular to the skull, aimed at the ipsilateral medial canthus and the tragus, with CSF expected at 5 to 6 cm; it is never advanced past 7 cm.

4. 04Tunnelling and levelling

   The catheter is tunnelled under the scalp to a separate exit site, secured, connected to the drainage system, and the chamber levelled against the tragus at the prescribed height.

Anatomy you need

The brain and its ventricles: Kocher's point triangulates the frontal horn of the lateral ventricle you are looking at.

What can go wrong

• Postoperative bleeding

  Tachycardia first, hypotension late; falling urine output; a distending abdomen or rising drain output.

• Surgical-site infection

  Wound erythema, warmth, discharge, and pain out of proportion, typically from postoperative day 4–7.