Rebleeding

¹⁰

• 
  

  Suspect if early deterioration occurs. Mortality is reported to be as high as 80%.

  
  
• 
  

  There is higher risk if patient has a poor-grade SAH, previous sentinel headache, or a large aneurysm.

  
  
• 
  

  Rebleeding is at its highest risk within 12 to 24 hours, with rates of rebleeding estimated to occur at 30% within 3 hours, 50% within 6 hours, and 4 to 13% in first 24 hours. Time to treatment is crucial.

  
  
• 
  

  To minimize the risk of rebleeding prior to securing the aneurysm, current recommendations include ¹¹ :

  
  
  
  
  • 
    

    Early repair (>6 hours post rupture) when appropriate

    
    
  • 
    

    Blood pressure control with systolic blood pressure (SBP) < 160 mm Hg or mean arterial pressure (MAP) < 110 mm Hg; care should be taken to avoid extremes in either direction

    
    
  • 
    

    Early use of anti-fibrinolytics can be considered from admission until time of aneurysm securing. Anti-fibrinolytics should not be started >48 hours or used longer than 72 hours due to risk of rebleeding. ^{4 , 10 , 11}

    
    
  • 
    

    Anyone treated with anti-fibrinolytics should be screened for deep vein thrombosis.

  
  
• 
  

  No current consensus on blood pressure management prior to securing the aneurysm. Current recommendation for SBP < 160 mm Hg or MAP < 110 mm Hg.

Aneurysm Treatment

There are two current methods for securing aneurysms: surgical clipping or endovascular coiling/embolization. The details regarding aneurysm treatment are outside the scope of this book.

Hydrocephalus

^{4 , 5 , 12}

1. 
   

   Acute hydrocephalus occurs in about 30% of patients but can vary widely from 15 to 87%. Drainage with external ventricular drainage (EVD) is associated with improved neurologic status.

   
   
2. 
   

   In a recent study comparing management of EVDs, the majority of institutions preferred to keep the EVD continuously open in both the unsecured and secured aneurysm (81 and 94%, respectively). ¹³

   
   
3. 
   

   Most institutions favor a gradual wean (96 hours) over a rapid wean (< 24 hours). Shunt placement has not been clearly associated with either weaning method. ^{5 , 12}

Seizures and Prophylactic Anticonvulsant Use

^{11 , 14}

• 
  

  Up to 26% of SAH patients have seizure-like episodes.

  
  
• 
  

  Risk factors include age >65 years old, thick SAH clot, intraparenchymal hemorrhage, rebleeding, and cerebral infarct.

  
  
• 
  

  There is no randomized controlled trial on prophylactic antiepileptic drug (AED) in SAH.

  
  
• 
  

  Nonconvulsive seizures are detected in 10 to 20% of comatose SAH patients.

  
  
• 
  

  Current recommendations include:

  
  
  
  
  • 
    

    Phenytoin should NOT be used for routine prophylaxis as it has been associated with worse outcome. Other anticonvulsant agents may be considered for prophylaxis.

    
    
  • 
    

    A short course of anticonvulsant (3–7 days) may be considered for patients without a history of seizure. Long-term use of anticonvulsant is NOT recommended.

    
    
  • 
    

    For patients with a seizure on admission, anticonvulsant agents should be continued at the discretion of the management team.

    
    
  • 
    

    Continuous electroencephalography (EEG) monitoring should be considered for high-grade SAH patients in coma and patients with acute neurologic decline.

Cardiopulmonary Complications

^{11 , 14 , 15}

• 
  

  Sympathetic stimulation and catecholamine surge mediate myocardial injury.

  
  
  
  
  • 
    

    35% elevated troponins, 35% arrhythmias, and 25% wall motion abnormalities

  
  
• 
  

  “Neurogenic Stress Cardiomyopathy” or “Stunned Myocardium”

  
  
  
  
  • 
    

    Syndrome of chest pain, dyspnea, hypoxemia, and cardiogenic shock

    
    
  • 
    

    Occurs within hours of aneurysm rupture

    
    
  • 
    

    Risk of sudden death in approximately 12% of the patients

    
    
  • 
    

    Symptoms are transient and can resolved within 1 to 3 days

    
    
  • 
    

    Supportive management

  
  
• 
  

  Cardiac abnormalities in patients who develop delayed cerebral ischemia have worse outcomes.

  
  
• 
  

  Symptomatic pulmonary complications can occur in approximately 20% of the patients while up to 80% may have impaired oxygenation.

  
  
  
  
  • 
    

    Neurogenic or cardiogenic pulmonary edema

    
    
  • 
    

    Acute lung injury

    
    
  • 
    

    Acute respiratory distress syndrome (ARDS)

  
  
• 
  

  Pulmonary complications are associated with higher clinical grade SAH and higher mortality.

  
  
• 
  

  Current recommendations include:

  
  
  
  
  • 
    

    Baseline electrocardiogram (ECG), transthoracic echocardiogram (TTE), and cardiac enzymes must be obtained on admission.

    
    
  • 
    

    Target euvolemia: If pulmonary edema is present then avoiding increased fluids and careful use of diuretics should be considered.

    
    
  • 
    

    Standard management of heart failure is indicated although tempered by the BP/cerebral perfusion pressure (CPP) goals needed to maintain neurologic stability.

Volume Assessment and Management

^{11 , 15 , 16}

• 
  

  Target fluid balance of euvolemia.

  
  
• 
  

  Avoid hypovolemia. It is associated with cerebral infarcts and worse outcome.

  
  
• 
  

  Isotonic fluids are recommended for volume replacement.

  
  
• 
  

  Avoid hypotonic fluids.

  
  
• 
  

  Regular assessment of volume status with both clinical data and physical examination can be supplemented by the use of noninvasive or invasive monitoring technologies when needed.

  
  
• 
  

  Routine use of pulmonary artery catheter is NOT recommended and central venous pressure (CVP) monitoring is NOT recommended as the sole measurement for volume status.

  
  
• 
  

  Fludrocortisone or hydrocortisone can be considered in patients who persistently maintain a negative fluids balance.