Shunt Complications in Children

• See also Adult hydrocephalus and shunt complications Adult Hydrocephalus and Shunt Complications.

Essentials

• The signs of shunt malfunction are similar to the signs of hydrocephalus:
  • the signs of shunt blockage and disconnection are the same as in hydrocephalus
  • if an infection is present the patient will also have signs of systemic inflammatory response
• Symptoms related to overdrainage (headache, tiredness, vomiting) are usually worsened by an upright position and therefore become prominent towards the evening.
• A suspicion of hydrocephalus or shunt malfunction in a child is an indication for an immediate referral to a paediatric hospital. The referral letter should include x-ray images of the head/brain and data relating to the growth of the child (height, weight and head circumference).
  • If the conscious level is affected or the child is unconscious, the medical staff at the hospital in charge of the child's care must be consulted regarding the need for a shunt or ventricular tap.
• Lumbar puncture is dangerous and contraindicated. The absence of papilloedema does not rule out increased intracranial pressure.

Hydrocephalus in a child

• In 90% of all cases, excluding tumours, hydrocephalus is diagnosed within the first year of life.
• In 45% of cases, the cause is prenatal (malformation, sequelae to cerebral haemorrhage/ischaemia/inflammation).
• Postnatal causes of hydrocephalus are cerebral haemorrhage (perinatal bleeds in small premature infants), infections (meningitis, encephalitis) and tumours.
• Patients with hydrocephalus are usually treated with a ventriculoperitoneal shunt, but nowadays a number of patients can be treated by an internal bypass operation, i.e. by endoscopic perforation of the bottom of the third ventricle.

Signs of disturbed circulation of cerebrospinal fluid (in hydrocephalus)

• Accelerated growth of head circumference in an infant or young child (head growth charts!) see Head Growth in Children.
• Tiredness, crying, difficulty feeding
• Headache (at night, first thing in the morning)
• Vomiting
• Blurred vision/impaired vision

Clinical findings in disturbed circulation of cerebrospinal fluid (in hydrocephalus)

• Infant: taut and bulging anterior fontanelle, widely open cranial sutures
• Impaired upgaze (”sunsetting”), strabismus (abducens nerve palsy), papilloedema
• Brisk tendon reflexes, ankle clonus
• Ataxia
• Dislike of being handled
• Decreased level of consciousness

Signs and symptoms of shunt complications: an emergency referral

• Swelling, redness or skin infection around the shunt site
• Vomiting, headache or irritability
• Abdominal pain
• Nuchal rigidity, opisthotonus
• Painful head or eye movements
• Abnormal eye movements on examination
• New-onset strabismus
• Recurrent seizures
• Headache or feeling unwell in the afternoons
• Decreased level of consciousness (shunt tap should be carried out before the transfer as the patient's condition may deteriorate rapidly whilst being transferred).
• Unexplained fever
• Immediate, sterile shunt tap, with a removal of 20-30 ml of cerebrospinal fluid is indicated as an emergency procedure in the following situations:
  • decreased level of consciousness with increased intracranial pressure being the only obvious cause
  • extensor rigidity
  • pupils dilated or not reacting to light
  • respiratory arrest.
• The medical staff at the hospital in charge of the child's care must be consulted before carrying out an emergency shunt tap.
• Also a perforation made at the bottom of the third ventricle may become obstructed, leading to similar symptoms and findings as seen in shunt obstruction.