Recovery From Surgery for Hydrocephalus due to Posterior Fossa Tumors in Children

Postoperative Orders 

  • ICU vs. standard care unit: A patient in good clinical condition preoperatively and after an uneventful tumor resection can be extubated and followed on a ward. If any concerns arise with regard to a poor level of consciousness or respiratory abnormalities, an ICU is the best option.
  • VS: Very close monitoring of vital signs (HR, BP, respiratory pattern) is of paramount importance. Major postoperative complications (e.g., posterior fossa bleeding) can present with bradycardia, hypertension, or respiratory abnormalities, and immediate management is essential. Reference values vary with age:
Vital sign < 1 year of age > 12 years of age
Respiratory rate 30–60 breaths/min 12–60 breaths/min
Heart rate 110–160 bpm 60–100 bpm
Blood pressure 55–75/35–45 mmHg 110–130/65–80 mmHg

 

  • BP parameters: In the ICU invasive BP monitoring from an indwelling peripheral line is the preferred method for any patient. Otherwise, BP should be monitored noninvasively for all children, taking care to use the correct cuff size.
  • IVF and rate: Fluid for maintenance typically is NaCl 0.9% + 20 mEq/l KCl or NaCl 0.45%. Its rate of infusion is calculated as 4 ml/kg for the first 10 kg, plus 2 ml/kg for the second 10 kg, and plus 1 ml/kg for each subsequent kg (15).
  • Ventilator support: Ventilator support is provided according to ICU protocols.
  • ICP parameters: Direct ICP monitoring should be considered for intubated and sedated patients in the ICU. If an EVD is already inserted, then the ICP can be monitored through the CSF column. Otherwise ICP-driven management is initiated (maintain at < 20 mmHg in older children and < 15 mmHg in children younger than 10 years). Accordingly, CPP is maintained as > 45–60 mmHg (age < 10 years) and > 50–70 mmHg (age > 10 years).
  • CSF drainage parameters/drainage bag setup: Initially, use a high set-up because of upward herniation risk (if tumor not resected yet) and because of subdural collections risk (after tumor resection): 15–20 cmH20. Aim for a drain of 2–5 ml/hour for babies or children with no tumor resection yet. In older children the draining rate can rise to 5–10 ml/hour but has to be < 20 ml/hour.
  • Diet: After the removal of a posterior fossa tumor, the swallowing mechanism should be assessed properly before feeding is begun. Paresis of the lower cranial nerves is dangerous for aspiration and lower respiratory infections. If such paresis occurs, then a nasogastric tube can be inserted or, in more severe and chronic cases, a gastrostomy tube.
  • HOB, positioning, activity, bathing: If the patient is in an ICU with increased ICP, then the HOB should be raised up to 45 degrees or even 60 degrees. Otherwise, there are no specific limitations for a child whose recovery is smooth and uneventful.

Medications and dosages including PRN drugs

Postoperative medication should be kept to minimal and only necessary requirements. Antibiotics for prophylactic purposes are of no use in the postoperative period.

  • Analgesia: Patients should receive proper analgesics at the appropriate doses according to pain scores. Some examples are as follows (3):
Class Agent Route Dose Frequency
Opioids        
  Morphine IV

< 50 kg: 0.1 mg/kg

> 50 kg: 5–8 mg

Every 2–4 hours

Every 2–4 hours

  Codeine IM

< 50 kg: 0.5–1 mg/kg

> 50 kg: 30–60 mg

Every 3–4 hours

Every 3–4 hours

Non-opioids
  Paracetamol (acetaminophen) PO

< 60 kg: 10–15 mg/kg

> 60 kg: 650–1000 mg

Every 4 hours

Every 4 hours

  Ibuprofen PO

< 60 kg: 5–10 mg

> 60 kg: 400–600 mg

Every 6 hours

Every 6 hours

 

  • Steroids: Usually dexamethasone, if it was commenced preoperatively. After a couple of days it can be tapered off.
  • Antiemetics: Ondansetron: For children 1 month to 18 years, give 100 micrograms/kg (maximum dose 4 mg) as a single dose before, during, or after induction of anesthesia (20).

Laboratory studies

  • Routine postoperative lab studies: CBC, ABG, BUN, and serum electrolytes are requested.
  • Evaluation for SIADH, salt wasting, etc.: Plasma and urine osmolality are analyzed.
  • CSF analysis: If an EVD is in situ, CSF samples (one or two/week) are taken for microbiology analysis and sensitivities and WBC counts.

Radiology studies

  • Plain x-rays: After ventriculoperitoneal shunt insertion, some surgeons like to have a baseline shunt series for future comparisons.
  • CT: A CT scan is obtained only when the patient’s condition deteriorates postoperatively or if there is evidence of pseudomeningocele or persistent CSF leak.
  • MRI: An MRI is obtained within the first 48 hours postoperatively with contrast enhancement for tumor residual. CSF flow studies can also be done to confirm ETV patency (if done preoperatively) or to assess third ventricle anatomy in case an ETV is needed after the tumor resection.

Physical therapy and orthotics

  • Rehabilitating deficits: After a smooth operation with no new deficits, the patient is encouraged to mobilize as soon as possible. If any degree of preexisting ataxia or other gait disturbances is present, then the patient can be supported by the physical therapy team for the appropriate time period.

Postoperative Morbidity

No unique morbidities are expected that would not be seen after a routine shunt placement or ETV.