Recall your medical school application?  Do you remember what you wrote about in your personal statement?  I would be willing to bet that a good majority of you wrote about wanting to “make a difference.”  Those of us that spend time in the ED certainly place ourselves in the position to be able to make that difference during acute life-altering moments!  The child who was healthy at 7:59am and then seizing at 8:00am comes to mind.  While an AVM is rare, it has a powerful ability to acutely alter the course of a life and those lives around it.

Arteriovenous Malformations

• Tangle of blood vessels that bypass the normal brain tissue and diverts blood directly to the venous system.
• The blood vessels are weaker than normal and can become more dilated, and thus even more fragile.
• They are uncommon, but true incidence is not fully known.
  • Estimated annual incidence of symptomatic AVMs = 1.1 per 100,000
  • Autopsy data suggests overall frequency of ~4.3% of population
• Often considered to be congenital; however, some have shown that kids that had them removed later developed new AVMs, so obviously there are other factors involved.

Pediatric Specific Considerations

Presentations

• Children with AVMs are more likely to present with hemorrhage than adults.
  • 80-85% will initially present with hemorrhage.
  • Also carries a mortality rate of 25%
• Very young children (< 2yrs), may actually present with High-Output Heart Failure due to the arteriovenous shunting.
• Seizures is another common presentation.
• Headache and isolated neurologic deficit also have been seen.
• Some will be incidentally picked up on imaging for other reason.

Risk of Hemorrhage

• There are several models that are used to attempt to help predict the natural course of the AVM… but they aren’t perfect.
• The Lifetime risk of hemorrage can be estimated with the formula:
  • Lifetime Risk % = 105 – (age of patient in years)
  • Obviously, young patients are more likely to develop a hemorrhage.
• If the AVM has already bleed, there is a higher risk of it bleeding again during the first year (up to ~18%).

Neurosurgical Options

• Resection
• Endovascular embolization
• Radiofrequency ablation (radiosurgery)
• Multimodality

• All are useful.  Generally, pediatric patients do warrant a more aggressive strategy given higher incidence of hemorrhage.

Simple Actions Matter

If you have determined that your patient has a bleed and has increasing ICPs… do some simple things that can make a difference:

• Elevate Head of Bed to 30 degrees
• Sedate… perhaps intubate (consider your drugs carefully and have excellent technique — First Pass Success is imperative as always!)
• Control pain

References