Recognition of symptoms in this nonverbal age group is challenging. Often it is the vigilance of healthcare professionals in developmental and growth assessment with charted documentation that bring signs, rather than true symptoms, to light.
- Failure to thrive: Failure to thrive may be especially true of infants with diencephalic tumors (6, 21).
- Feeding difficulty: Feeding difficulty may be a nonspecific feature of malaise in an infant or associated specifically with a neurological deficit related to the tumor such as oropharygeal dysfunction.
- Delayed development: There may be failure to meet motor developmental milestones.
Symptoms of elevated ICP
- Due to hydrocephalus: Elevated ICP is most commonly due to hydrocephalus.
- Vomiting: Although vomiting is an important feature of elevated ICP, gastroesophageal reflux is probably the most common cause of vomiting in infants. One must also consider pyloric stenosis, especially in the male infant.
- Accelerated head growth: Cross-centile head circumference growth may be present.
- Bulging fontanelle: There may be bulging anterior fontanelle/failure to close.
- Sutural diastasis: Sutural diastasis and, therefore, cranial expansion may accommodate the rise in ICP and mask the sign of a bulging or tense anterior fontanelle in the early stages until decompensation occurs. Observation of serial head circumference measurements are therefore critically important
- “Sun-setting” eyes: An upgaze paresis associated with hydrocephalus caused by pressure on the periaqueductal brainstem structures. The sclera above the iris in the downward gaze position gives rise to the ‘setting sun’ description.
Focal neurological signs and symptoms
- Varies with location: These depend on the location of the tumor.
- Focal weakness
- Truncal ataxia
- Extraocular muscle paresis
- Seizures: More common with cortical tumors.
- Fluid resuscitation: If possible, enteral fluid resuscitation should be encouraged, either by oral administration or nasogastric tube. A dietician can aid with choice of rehydration solution. Intravenous therapy is not usually required unless the infant is to be kept fasting for investigation or urgent intervention.
- Electrolyte imbalance: Electrolyte imbalance is especially common in infants with a history of prolonged vomiting.
- Corticosteroids: Corticosteroids may be administered intravenously or orally. The most common agent is dexamethasone. The recommended dose for dexamethasone for brain tumor-associated edema is 250–500 µg/kg/24 hours in divided doses (15). [NB: This dosage recommendation is taken from a publication in 2003 by the Royal College of Paediatrics & Child Health (UK), which has been superseded by the Children’s British National Formulary (CBNF). The latter does not carry a specific dosage schedule for tumor-associated edema. Dose regimen should be confirmed with local pharmaceutical guidelines.]
- Ventricular tap: The presence of an open anterior fontanelle allows for emergency needle ventriculostomy in the case of acute life-threatening hydrocephalus. More formal external ventricular drainage may subsequently be performed, or an ETV considered in the older infant (≥ 6 months of age).
- BP parameters, 70–90 mmHg systolic: As a rule of thumb, the patient’s age in years x2 + 80 mmHg is the target systolic blood pressure in children.
- IV fluids and rate for infant – 4ml/kg/hr: The 4,2,1 rule is a simple formula to calculate baseline fluid requirements for children. The rule states that the total hourly rate of IV fluids for a child is 4 ml/kg/hr for the first 10 kg of body weight, plus 2 ml/kg/hr for the next 10 kg, plus 1 ml/kg/hr for the remainder of body weight. Most infants weigh less than 10 kg. Volumes included in IV drug preparations and volumes lost by wound or CSF drainage become important factors in calculating replacement volumes in infants because of their small fluid volume.
- CSF drainage parameters: The CSF production rate is 0.3 ml/kg/hr. CSF drainage therefore should equate to production. One must of course take into account increases in CSF production with choroid plexus tumors. Adjusting the drainage receptacle to impart a calculated resistance that allows drainage only when the ICP exceeds the set resistance can also control the drainage rate. Replace drainage by adding to fluid intake ml for ml with 0.9% NaCl.