Subarachnoid Hemorrhage

 

 

Considerations

 

  • Emergency, full stomach 

  • Unsecured aneurysm with potential for rebleeding:

    • Avoid hypertension & changes in transmural pressure

    • Potential massive hemorrhage

  • ↑ ICP & prevent secondary injury:

    • Avoid cerebral ischemia: CPP 60-70/MAP 80-90 mmHg

    • ↓ ICP

    • ↓ CMRO2: barbiturate coma, burst suppression, mild hypothermia 

    • Maintain euglycemia, normocapnia

  • Neurologic complications:

    • Rebleed

    • Cerebral vasospasm

    • Obstructive hydrocephalus

    • Seizures

  • Medical complications:

    • Neurogenic pulmonary edema

    • Myocardial dysfunction, arrhythmias 

    • Electrolyte imbalances (hyponatremia due to cerebral salt wasting, SIADH)

 

 

Goals

 

  • Hemodynamic control & monitoring:

    • Minimize transmural pressure to avoid rebleed 

    • Avoid acute hypertensive episodes (essential because rebleed is often fatal)

    • Keep SBP < 160 mmHg (AHA guideline 2012) & keep MAP > 85 mmHg (to prevent ischemia) 

  • Facilitate surgical exposure/control ICP

  • Protect from secondary brain injury:

    • CPP 60-70/MAP 80-90 mmHg

    • ↓ ICP

    • Normocapnia

    • ↓ CMRO2: mild hypothermia, barbiturates, DHCA (deep hypothermic circulatory arrest)

    • Euglycemia: glucose < 11 mmol/L

    • Prevent vasospasm (nimodipine, pravastatin)

 

 

Conflicts

 

  • Aspiration risk (RSI) vs tight hemodynamic control to prevent rebleed/cerebral ischemia (titrated induction)

  • Minimize transmural pressure (deep induction to prevent rebleed) vs maintain CPP (hemodynamic support to prevent ischemia)

 

 

Pregnancy Management of Acute Intracranial Bleed 

 

  • Decision to proceed with surgery:

    • If 3rd trimester (>32 weeks)

      • Consider simultaneous procedure, or cesarean section first followed by intracranial procedure 

    • If pre-term viable (24-32weeks):

      • Do intracranial surgery, then wait for fetal maturity 

      • Deliver if fetal distress 

    • If pre-term non-viable (<24weeks):

      • Do intracranial surgery, then wait for fetal maturity 

  • Induction:

    • Titrated to protect against rebleed vs secondary brain injury

    • Accept aspiration risk 

  • Mannitol:

    • Risk of fetal dehydration 

    • If tight head → give 

    • If non urgent indication → discuss with neurosurgery, avoid if possible 

  • PaCO2 management:

    • Maintain around 30 mmHg

    • Consider maintaining in high 20's if tight head