Anesthesia Considerations 

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