Post-Haemorrhagic Hydrocephalus

Post-haemorrhagic hydrocephalus is ventricular enlargement from impaired cerebrospinal fluid circulation or absorption after intracranial bleeding. It follows intraventricular haemorrhage in preterm infants, subarachnoid haemorrhage, intracerebral haemorrhage with ventricular extension, and trauma.

It develops in about 20 to 30% of survivors of aneurysmal subarachnoid haemorrhage and in 25 to 50% of preterm infants with severe intraventricular haemorrhage.

Pathophysiology. Early obstruction comes from clot in the ventricles or aqueduct. Late communicating hydrocephalus comes from scarring of arachnoid granulations and basal cisterns by blood breakdown products.

Acute presentation is headache, vomiting, falling consciousness, and impaired upgaze. Subacute and chronic presentation is gait apraxia, cognitive slowing and urinary urgency. Infants show rapid head growth, a tense fontanelle, sunsetting eyes and apnoea.

Red flags.

• Falling Glasgow Coma Scale score after haemorrhage.
• Pupil change, bradycardia with hypertension.
• Wound swelling or fever in a child or adult with a shunt.

Repeat CT or MRI shows ventricular size, with transependymal oedema in active hydrocephalus. Cranial ultrasound is used in infants, with serial head circumference. Lumbar puncture with opening pressure and a drainage test help in chronic cases. Exclude infection and rebleeding.

Acute. Raise the head to 30 degrees and place an external ventricular drain for obstructive hydrocephalus with reduced consciousness. Do not perform lumbar puncture when there is a mass effect or obstruction. Hyperosmolar therapy is a bridge: 3% sodium chloride 250 mL IV over 15 to 20 minutes, or mannitol 20% 0.5 to 1 g/kg IV over 15 to 20 minutes.

Subacute. Serial lumbar puncture or lumbar drain may allow recovery without a shunt, particularly after subarachnoid haemorrhage.

Permanent diversion. Ventriculoperitoneal shunt with programmable valve for persistent hydrocephalus. Endoscopic third ventriculostomy for obstructive cases.

Infants. Ventricular access device or ventriculosubgaleal shunt as a temporary measure until weight and cerebrospinal fluid protein permit a permanent shunt.

Shunt failure and infection. Treat headache, vomiting or drowsiness as failure until proven otherwise. Suspected infection needs cerebrospinal fluid culture and prolonged antibiotics with shunt removal or externalisation.

Monitoring. Ventricular size, head growth, neurodevelopment, vision and shunt function.

Referral and escalation. Refer urgently to neurosurgery.