What are the treatment options for intracranial hypertension?

Treatment for Intracranial Hypertension

Treatment of intracranial hypertension should follow a stepwise approach, beginning with simple measures and progressing to more aggressive interventions as clinically indicated, with external ventricular drainage being a highly effective option for persistent intracranial hypertension despite initial measures.

Initial Assessment and Monitoring

• Intracranial hypertension is defined as sustained ICP >20 mmHg 1
• ICP monitoring is recommended in patients with:
  • Signs of high ICP on brain CT scan
  • Extracranial surgical procedures (except life-threatening conditions)
  • When neurological evaluation is not feasible 2

Treatment Algorithm

First-Tier Interventions

1. Basic Measures:

   • Head elevation (30°) to improve venous drainage
   • Proper positioning of the head in neutral alignment
   • Adequate analgesia and sedation to control pain and agitation 2
   • Temperature control to prevent fever
   • Maintain normocapnia through controlled ventilation with end-tidal CO2 monitoring 2

2. CSF Drainage:

   • External ventricular drainage is highly effective for persistent intracranial hypertension despite sedation and correction of secondary brain insults 2
   • Even small volume CSF removal can markedly reduce intracranial pressure
   • Can be inserted using neuronavigation in cases of small ventricles 2

3. Osmotic Therapy:

   • Mannitol:

     • Dosage: 0.25 g/kg IV infused over 30 minutes, repeated every 6-8 hours as needed 3
     • Monitor fluid/electrolytes, serum osmolarity, and renal/cardiac/pulmonary function
     • Discontinue if renal, cardiac, or pulmonary status worsens 3
     • Caution: Can cause hypovolemia, renal failure, and rebound intracranial hypertension 2

   • Hypertonic Saline:

     • Alternative to mannitol, effective even in cases refractory to hyperventilation and mannitol 2
     • Optimal concentration and administration mode still being investigated

4. Controlled Hyperventilation:

   • Rapidly reduces ICP but should be used judiciously
   • Transient effect as brain tissue accommodates to pH changes
   • Risk of cerebral ischemia due to vasoconstriction
   • Not recommended for prolonged use or aggressive reduction of PaCO2 2

Second-Tier Interventions (for Refractory Intracranial Hypertension)

1. Barbiturate Coma:

   • For refractory intracranial hypertension when other measures fail
   • Reduces cerebral metabolic activity and subsequently ICP
   • Monitor cerebral electrical activity (aim for burst suppression)
   • Major risks: hypotension, cardiovascular depression, respiratory depression 2
   • Requires intensive monitoring and management of side effects

2. Decompressive Craniectomy:

   • Consider for refractory intracranial hypertension in multidisciplinary discussion 2
   • Large temporal craniectomy (>100 cm²) with enlarged dura mater plasty is commonly used
   • RESCUE-ICP study showed reduced mortality (26.9% vs 48.9%) compared to barbiturates but with more patients having poor neurological outcomes 2
   • Decision should be case-by-case, considering age and other factors

Special Considerations

• Surgical Indications:

  • Removal of symptomatic extradural hematoma
  • Removal of significant acute subdural hematoma (thickness >5mm with midline shift >5mm)
  • Drainage of acute hydrocephalus
  • Closure of open displaced skull fracture
  • Removal of brain contusions with mass effect 2

• Glucose Management:

  • High blood glucose on admission predicts increased 28-day case-fatality rate
  • Control hypoglycemia or hyperglycemia 2

Pitfalls and Caveats

1. Monitoring-related:

   • ICP must be measured invasively for accurate assessment
   • Consider ICP dynamics, not just absolute values

2. Treatment-related:

   • Mannitol: Check for crystallization before administration; warm to dissolve if present
   • Avoid mannitol in patients with anuria, severe hypovolemia, or pulmonary edema 3
   • Hyperventilation: Rapid normalization after prolonged use can cause rebound ICP increase
   • Barbiturates: Significant cardiovascular side effects; avoid in patients with hemodynamic instability

3. Patient-specific:

   • Many patients with smaller intracranial hemorrhages may not have increased ICP and require no specific measures 2
   • Young patients with absent perimesencephalic cisterns and tight brain on CT may respond better to hyperventilation and hypnotics than osmotic agents 4

The treatment approach should progress systematically through these tiers, with careful monitoring of patient response and adjustment of therapy accordingly.