Synopsis
Detect neurological deterioration caused by acute hydrocephalus after spontaneous haemorrhage or an intracranial tumour, separate their mechanisms, and coordinate urgent CSF diversion with definitive cause control.
- After aneurysmal SAH, hydrocephalus can be acute from ventricular/outlet obstruction by blood or later from impaired absorption; diagnose from symptoms and change on imaging.
- In spontaneous ICH with intraventricular extension, hydrocephalus contributing to impaired consciousness is an accepted indication for EVD to reduce mortality, although functional-outcome evidence is less certain.
- Posterior-fossa haemorrhage is not simply supratentorial ICH in a different location: direct brainstem compression and a tight compartment can make evacuation or decompression central to rescue.
Key red flags
Any fall in GCS or new pupil, gaze, motor or respiratory abnormality after subarachnoid, intraventricular or intracerebral haemorrhage.
Rapid vomiting, headache, reduced alertness or new sixth-nerve or upgaze abnormality in a patient with a third-ventricular or posterior-fossa tumour.
Intraventricular extension with enlarging ventricles and impaired consciousness supports urgent EVD assessment in spontaneous ICH.
Cerebellar haemorrhage or posterior-fossa tumour with hydrocephalus and brainstem compression may need lesion evacuation or decompression; ventricular drainage alone may be insufficient or hazardous.
A blocked or dislodged CSF drain, sudden cessation or excess of drainage, new wound leak or acute neurological change is an immediate device-and-patient emergency.
Anticoagulant use changes haemorrhage management, but reversal agent, dose and availability must follow the current haemorrhage-specific UK and local pathway.
Reassess headache, vomiting, GCS components, pupils and focal signs. Compare CT for new ventricular enlargement, intraventricular blood and cisternal obstruction while also considering rebleeding, seizure, ischaemia, sodium disturbance and infection.
Reduced consciousness with IVH and hydrocephalus supports urgent EVD assessment. Keep spontaneous ICH distinct from traumatic bleeding, and remember that EVD treats hydrocephalus rather than the parenchymal haematoma itself.
Look for declining consciousness, gaze abnormality, ataxia when testable, cranial-nerve signs and brainstem compression on CT. Adult spontaneous cerebellar ICH with hydrocephalus or brainstem compression requires urgent direct neurosurgical assessment rather than assuming an EVD alone completes treatment.
New deterioration, unexpectedly absent drainage, loss of an expected CSF waveform, fluid leakage, tubing disruption or a changed drain position requires immediate escalation without unsupervised flushing or re-levelling.
Reasoning priorities
Identify acute hydrocephalus, intraventricular blood, haematoma expansion, posterior-fossa compression and gross tumour mass effect.
Compare with the prior scan and correlate ventricular change with neurological trajectory. Basal-cistern effacement, transependymal oedema and a visible obstruction increase concern, but absence of dramatic enlargement does not dismiss a deteriorating examination.
Worked reasoning
An adult with spontaneous ICH and intraventricular extension becomes drowsier and CT shows acute hydrocephalus.
- Recognise hydrocephalus contributing to impaired consciousness, call neurosurgery and critical care immediately, and stabilise airway, oxygenation and circulation.
- Repeat and document GCS components, pupils and motor findings, obtain urgent comparison CT, and assess the haemorrhage-specific blood-pressure, haemostasis and cause pathway in parallel.
- Prepare for EVD insertion by the neurosurgical team because current spontaneous-ICH guidance recommends ventricular drainage in this clinical pattern to reduce mortality.
- Do not treat the EVD as definitive control of the parenchymal bleed; continue spontaneous-ICH monitoring and assess whether evacuation or other surgery is indicated by location, mass effect and trajectory.
- After insertion, use the named unit/device protocol for level, drainage, clamping, sampling and troubleshooting, and verify response through examination, imaging and authorised device observations.
A stable patient has ventriculomegaly caused by a third-ventricular, aqueductal or posterior-fossa lesion.