Arteriovenous Malformations

AVM

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

Ogilvy CS, Stieg PE, Awad I, Brown RD Jr, Kondziolka D, Rosenwasser R, Young WL, Hademenos G; Special Writing Group of the Stroke Council, American Stroke Association. AHA Scientific Statement: Recommendations for the management of intracranial arteriovenous malformations: a statement for healthcare professionals from a special writing group of the Stroke Council, American Stroke Association. Stroke. 2001 Jun;32(6):1458-71. PMID: 11387517. [PubMed] [Read by QxMD]

Sean Fox

I enjoy taking care of patients and I finding it endlessly rewarding to help train others to do the same. I trained at the Combined Emergency Medicine and Pediatrics residency program at University of Maryland, where I had the tremendous fortune of learning from world renown educators and clinicians. Now I have the unbelievable honor of working with an unbelievably gifted group of practitioners at Carolinas Medical Center. I strive every day to inspire my residents as much as they inspire me.

You may also like...

4 Responses

  1. November 24, 2014

    […] you are currently completing a PICU term, you will know that AVMs are rare. But when they happen, the effects are alarmingly sudden. Sean Fox talks us through them at […]

  2. March 4, 2016

    […] Occupying Lesion (ex, AVMs, tumors, intracranial […]

  3. July 30, 2017

    […] Down’s Syndrome). We have also looked at what can happen when arteries form incorrectly (ex, AVM). Now let us take a moment to ponder the issues that can arise when an artery finds its origins […]

  4. July 30, 2017

    […] We have previously covered some important conditions to consider when evaluating headache (ex, AVM, RMSF, Meningitis, Post-LP, Moyamoya, Migraine, Pseudotumor, and Pheochromocytoma). Many of these […]

Leave a Reply

Your email address will not be published. Required fields are marked *