AAA – Always Scary!

Photo Credit: Edward Horsford

AAAs are Always Scary! (for me)

It’s one of the hardest diagnosis to make, usually it’s diagnosed incidentally, and once it’s ruptured – the prognosis is extremely poor and highly fatal.  Some people look really good, are misdiagnosed with musculoskeletal back pain, and discharged home.

Abdominal Aortic Aneurysm (AAA) is a true emergency.

An aneurysm is a dilation of the arterial wall. A true aneurysm involves all 3 layers of the vessel wall (intimata, media, and adventitia).

A diameter of 3.0 cm or greater is considered an AAA. Aneurysms 3.0-5.0 cm are less likely to rupture. Prompt Repair is considered with an aneurysm of 5.0 cm or greater and has a greater chance for rupture.

Pseudoaneurysm (false aneurysm) develops at a site of previous AAA repair, vessel cauterizations, trauma, or infection. Consists only part of the vessel wall and surrounding tissue. Can spontaneously thrombose.

Most AAA are discovered incidentally.

You don’t have much to go on. Especially at triage or when they first come into your resus bay and you’re initially thinking this patient has a different diagnosis or rule out. This is one of the rare incidences when I will say it’s okay to go with your “gut feeling” – but try to back it up with clinical presentation.

Clinical Presentation

  • Sudden abdominal/chest/back pain
  • Low BP or high BP – variable at times
  • Pulsatile, abdominal mass 
    • Aortic bifurcation is at the level of the umbilicus. AAA can be palpated at or above this level. May extend below the umbilicus if the iliac arteries are also aneurysmal.
  • Hypotension associated w/poor prognosis
  • Lower peripherals are blue – already ruptured
  • Mental status
  • Diaphoresis
  • Syncope
  • Flank, groin/inguinal, hip, thigh, scrotum pain – less common

Ruptured AAA – Pain-Hypotension-Mass Triad

Reality is if you get 2 out of the 3, most likely the AAA is ruptured. Some present with only 1 or 2 symptoms. Others have ZERO components.

Risk Factors

  • Male 50+, Women 50+, Women who recently gave birth
  • Smoker
  • Familial history. First-degree relative with an aortic aneurysm
  • Peripheral arterial disease

Suspect AAA? Say Something!

If you suspect, even if it’s just to rule out a differential – say something! Not to yourself – but to the provider! They may not have reached the same conclusion at the same time. Provider may not received the same information as you. Time is of essence! Do not delay communication. Encourage the provider to perform a RUSH exam immediately. If dilation is found on the RUSH exam, Vascular must be consulted immediately!

Immediately prepare for CT with contrast, the OR, and a lot of blood products may be needed.

  • Get your Pt naked! Strip all clothing immediately before you start placing monitoring leads.
    • Include dentures, hearing aids, jewelry, wallet, phone.
    • Obtain family member’s name and telephone number that you gave the property to them. If not call security if you have time to obtain the property or per hospital protocol.
    • Document this in the chart!
  • Place on both a Travel monitor and Defib monitor.
    • Anticipate that you are going to CT immediately after labs and IVs are obtained.
    • If CT is going to be delayed, add on your normal telemonitoring. Yes, I put on all 3. You don’t have time to switch out once CT is ready. Just BE READY.
  • Provider is performing RUSH exam while you are doing all of this.
  • Get that CT with intravenous contrast ASAP! Call CT and tell them you’re pushing your patient in.
    • Do NOT wait for any creatinine level prior to obtaining the Ct w/IV contrast. Especially if suspicion is confirmed or high suspicion off the RUSH exam.
    • Exception: Known Renal Failure patients – you can use a regular CT to diagnose. Know your facility’s protocol.
  • Obtain code status.
  • Obtain 2-3 IV lines Get GOOD IVs.
  • Draw labs and pre-op labs. Get 2 Type & Cross – may not already be in your system.
  • Get a quick POCT Hct level!
    • If the Hct level is low – be prepared to transfuse blood.
    • If the Hct level is really low – be prepared to initiate massive blood transfusion.
  • Maintain SBP I like to my SBP to be around 95.
    • The goal is to not make the rupture worse.
    • Really watch mental status
    • HR, BP, and SpO2 – is there an increase in demand?
    • Color? Pale?
  • Prepare for Blood Transfusion
    • If an AAA is ruptured – it’s ominous and will most likely need lots of blood. Think Massive Transfusion Protocol (MTP) and using that Level 1 Rapid Infuser
    • Remember, O Negative for women of child-bearing age. Otherwise O Positive is okay to use for males and female 55+.
  • Transfusing Blood.
    • Base this on clinical presentation and Hct/Hgb/Plt levels if you have them.
    • Treat like a trauma patient with hemorrhagic blood loss.
    • Initiate MTP – this pt does NOT have the time to wait for a T&C and matching blood.
    • Obtain PRBC, FFP, Platelets, and CRYO
    • AAA is ruptured – I have my platelets running open in a peripheral line.
    • Then I’m rapidly infusing PRBC and FFP through my Level 1 Infuser. If you don’t have it or pushing pt to the CT/OR – use a pressure bag.
    • I think warm whole blood route is best. Alternate between PRBC and FFP for a 1:1 ratio.
      • For more info on whole blood resuscitation, click here

Definitive Treatment is surgical repair in the OR.

References

Rosen’s Emergency Medicine: Concepts and Clinical Practice, 9th edition. Ron Walls, Robert Hockberger, Marianne Gausche-Hill

Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8th Edition. Judith Tintinalli, J. Stapczynski, O. John Ma, Donald Yealy, Garth Meckler, David M. Cline

3 thoughts on “AAA – Always Scary!

  1. Hola ! Awesome overview of AAA. Only seen it once in ED, not a great outcome. Often times people would rush for pain relief and I totally agree with your comment on withholding analgesics. keep up the great work. Congratlations from the Elmhurst Crew 🙂