Shunt malfunction

Shunts sometimes go wrong. There are various reasons why they may malfunction and need specialist medical intervention, and being able to recognise the possible signs and symptoms can be vital.

If shunts block, they are unable to drain the excess CSF and the pressure within the head (intracranial pressure, or ICP) increases.

Acute shunt malfunction

Acute shunt malfunction in babies and very young children occurring before the bones of the skull begin to fuse together can lead to increase in head circumference before signs of raised intracranial pressure become obvious. Other signs include:

  • bulging or tense fontanelle (‘soft spot’)
  • separation of the bones of the head (looking like ridges or furrows across the top of the head, or down the centre of the forehead)
  • lethargy – not wanting to play or do anything when awake
  • sleepiness (babies and small children should be fully alert when awake)
  • needing to be woken for feeds, slow and reluctant to feed, falling asleep during feeds
  • irritability, high pitched crying
  • sunsetting eyes (eyes look downwards, showing white above the coloured part instead of below)
  • vomiting.

In older children and adults the signs and symptoms may vary from person to person, and in the same person from one shunt malfunction to the next. The signs and symptoms below should be for guidance only. Not everyone will present with all the symptoms.

Possible signs and symptoms of shunt malfunction include:

  • headaches
  • neck pain
  • dizziness
  • vomiting
  • photophobia (light sensitivity) or other visual disturbances
  • drowsiness
  • seizures
  • loss of consciousness

People who have had previous shunt malfunctions may recognise their own ‘individual’ symptoms of raised pressure, but sometimes new signs and symptoms can present from one shunt blockage to the next.

In cases of unusual drowsiness, becoming unresponsive, reducing level of consciousness or unconscious: THINK SHUNT

People with suspected acute shunt malfunction should be seen at a Neurosurgical Unit within four hours of the onset of symptoms.

In the event of suspected acute shunt malfunction:

  • Call 999; arrange transport to a local Accident & Emergency Unit. Ensure paramedics and A&E staff are aware of shunt / hydrocephalus - Shine Shunt Alert Cards may be helpful
  • Call the neurosurgical unit if the person is under a neurosurgical team. If delayed in A&E triage, call the neurosurgical unit again
  • Encourage liaison between emergency services and neurosurgical unit.

Some people/ families may have their own agreements with their neurosurgical units in event of emergencies, such as ‘open access’ arrangements. These should be clearly recorded in healthcare plans etc.

Unless you have arrangements in place to go straight to your neurosurgical centre, you should go to your local A&E. Trying to get yourself to another town or city could result in a delay in getting treated.

Shunts can also malfunction over a prolonged period, and symptoms may be less clear, possibly including:

  • fatigue
  • general feelings of being unwell, lethargy
  • new or worsening visual or perceptual problems
  • changes in behaviour
  • decline in academic / mental / cognitive performance.

Review by a neurosurgeon should be arranged if chronic shunt problems are suspected. The person with the shunt may be less aware of the changes than the people around them, so discuss what you’re noticing, and offer support and prompting to get medical attention.

Chronic VA shunt infection can present with anaemia, persistent cough or kidney problems. If you have a VA shunt and have felt generally unwell for some time, ask your GP to arrange a blood test.

Donate Become a member