Okay, guys. We have a extremely important question here.
I almost am willing to bet you, you will see something like this on your board exam
and I'm sure you'll be tested on it on your shelfs, so let’s jump right in.
A 69-year-old male with a long-standing history of hypertension and high cholesterol
presents with abdominal pain and bruising on his feet.
The patient states that his symptoms started about a week ago and have steadily worsened.
He describes the abdominal pain as mild to moderate dull and deeply localized in the umbilical region.
The past medical history is significant for two transient ischemic attacks six months prior,
characterized by a sudden, right sided weakness and trouble speaking
but recovered fully within 30 minutes.
His current medications are sildenafil 100 mg orally as needed.
The patient reports a 30-pack-year smoking history and heavy alcohol use on the weekends.
Review of systems is significant for decrease appetite and feeling easily full.
His vital signs are a temperature of 37°C, blood pressure is 155/89, his pulse is 89,
respirations are 16, and his oxygen saturation is 98% on room air.
On physical examination, the patient is alert and cooperative, the cardiac exam is normal.
His lungs are clear to auscultation but a carotid bruit is present on his right side.
The abdomen is soft and nontender, but bowel sounds are present
and a pulsatile abdominal mass is felt in the lower umbilical region.
The patient’s feet have an appearance as seen in the image below.
Abdominal ultrasound reveals the presence of an abdominal aortic aneurysm, AAA.
Contrast CT reveals a small unruptured AAA, measuring a diameter of 4.1 cm.
High flow supplemental oxygen and fluid resuscitation are initiated.
Morphine sulfate and metoprolol are administered.
Which of the following is the best course of treatment for this patient?
Answer choice A: Discharge with clinical surveillance and annual ultrasound;
Answer choice B: Discharge with clinical surveillance and ultrasound every six months;
Answer choice C: Elective endovascular repair;
Answer choice D: Elective open surgical repair; or
Answer choice E: Emergency open surgical repair.
Now take a moment to come to the answer choice yourself before we go through it together.
Okay, like I was saying this is a very high-yield question
and I'm even willing to bet you will see it on real test day and you should see it on your shelf.
Now, let’s look at our question characteristics.
Well, this is a surgical question.
We have a patient coming in with a AAA, you call surgeons when you have AAA problems.
Now this is a two-step question.
The first thing we have to do is figure out what’s the diagnosis.
Yeah, the question tells you it’s a AAA, but there's a lot of subtleties we need to figure out.
And based on our understanding of what the diagnosis is we need to come to the best course in management
and of course here the stem is required because there's lots of detailed
and critical information that we need to go through to come to the correct answer choice.
So let’s go through it.
Here we have a male who's got a hypertension history and also a history of high cholesterol
and he’s coming in with the chief complaint of abdominal pain.
Now when you hear abdominal pain really our differential diagnosis involves the systems of the GI, the Urinary, and Cardiovascular.
Now, let’s go through the characteristic of this patient’s pain using the Socrates mnemonic.
Now starting with the site -- he’s noticing that the abdominal pain is around the umbilical origin.
Now here, we wanna make sure that we rule out appendicitis so we put that in the back of our mind.
The onset was about a week ago, the characteristic is dull, there is no comment of radiation,
and the association is bruising on his feet.
And remember that he has an underlying condition of hypertension so this could potentially be an acute or chronic problem.
Now, the timing of his pain is constant and for exacerbating
or relieving factors nothing is really mentioned that makes it better but it is gradually becoming worse.
And the severity is mild to moderate.
Now when going to the characteristics of this patient’s pain, nothing really here suggests a GI or urinary involvement.
For GI we wanna hear things like stool changes, abnormal bowel sounds or for urinary changing in urinary frequency, etc.
So really, our focus is going to switch to the cardiovascular system.
Now, you could make the argument to me but Mo, someone mentioned to me,
if you're in the question stem -- loss of appetite, early onset satiety -- well, that’s fine,
but those are really nonspecific and they're not specific to GI or urinary so focus on cardiovascular.
Now when looking at the cardiovascular system, you were told that the patient has an abdominal aortic aneurysm.
Abdominal ultrasound, remember, revealed the presence of the abdominal aortic aneurysm
and they got a contrast CT that showed an unruptured abdominal aortic aneurysm measuring 4.1 cm.
Now, this patient absolutely has risk factors to have a AAA,
he’s male, he's got a significant smoking history, he's got hypertension history,
and on exam, he has a pulsatile abdominal mass so this is all consistent and it makes sense for him to have a AAA.
Now, what's subtle about this question and makes it actually much, much more testable
is that he has signs and symptoms of embolization being present.
Now, the first thing you're going to see is that in the picture, they're showing you what's called livedo reticularis
which is something you can see in atheroembolic disease.
Also we're told he's had multiple TIAs where he has this right sided weakness and speech problems,
left MCA territory of course, so we're really told this guy has symptomatic embolization,
the feet are bruising and he's having emboli to his brain where he's having weakness and speech problems.
This is a problem, this is scary.
So our diagnosis is, this guy has symptomatic abdominal aortic aneurysm
because there is distal embolization involving the brain and his extremities.
Now, that we know, okay, we're gonna call it the diagnosis of symptomatic abdominal aortic aneurysm,
we need to figure out the best course of treatment.
Now, when trying to figure out the management for AAAs, it really depends on the size
and the presence and absence of symptoms.
Now size is the main risk factor for rupture, which would be a medical emergency.
Now, this patient actually has a small AAA, it’s measuring 4.1 cm.
Surgical repair is indicated if the AAA is greater than 5.5 cm,
but this patient has signs and symptoms like we said, of distal embolization involving the brain and his extremities,
so because he has a AAA with embolization, hence a symptomatic AAA,
this is now considered a medical emergency just like if it was very dilated.
Now, the complication here is that this guy could have a real stroke,
he has been lucky to be having TIAs or he could have embolization to another organ and fairly damage another one,
so the only answer choice here that will be applicable that sounds emergent is answer choice E, emergency open surgical repair.
Answer choices A and B, discharging or answer choices C and D elective repair,
would not be appropriate, this is a medical emergency
and that’s why I keep telling you with so high-yield,
the boards want you to know how to manage certain emergency conditions and this is one of them.
They don’t want you out there in the community practicing being oblivious to this.
So thus the best choice here is emergency open surgical repair.
Now, let’s go through this answer choices in a little bit more detail to make sure it makes sense to you, it’s that important of a question.
Now, this patient showing up, like we said, a symptomatic abdominal aortic aneurysm.
Now he has of course risk factors for these: high cholesterol, hypertension, smoking,
and we see the AAA on ultrasound and CT and see that its 4.1 cm wide.
Now he's got a history of TIAs, we even have signs and symptoms of wide spread atherosclerotic disease.
We are told he has a carotid bruit and we even see livedo reticularis in his feet.
Now, livedo reticularis can also be called blue feet syndrome which is caused by having atheroemboli to the lower extremities.
Now, given that he has distal emboli to brain and extremities,
emergency open surgical repair is indicated irrespective of the size of the AAA.
Now let’s go through why the other answers are wrong because that will also really give you better learning.
Now, answer choice A, discharge with annual surveillance with ultrasound.
Now, discharging -- this is recommended for asymptomatic AAAs that have a diameter of 3-4 cm,
and if continued dilation is found then you can refer to surgery for appropriate intervention.
Now, this patient’s coming in with a 4.1 cm so annual ultrasound would not be appropriate,
that’s why you can delete that one. Now, answer choice B, which is discharge with ultrasound ever six months,
now that’s recommended for asymptomatic patients that have a AAA diameter of 4-5 cm.
Now again our patient has 4.1 cm so annual ultrasound would be appropriate if he was asymptomatic,
but he has atheroemboli, so this is not applicable but you could see,
if they would have give you that diameter, now you know when to pick annual versus every six months ultrasound.
Now let’s look at Answer choice C, elective endovascular repair.
Now endovascular repair as opposed to open repair is a minimally invasive approach to repair a AAA.
There is significantly less surgical risk of course than an open repair
and it’s indicated for those who cannot tolerate surgery or for whom open surgery is contraindicated.
Now, of course, endovascular repair is less surgical risk
but often requires some degree of replacement or some type of revision in most cases.
Now, answer choice D, elective open surgical repair is indicated for those who are hemodynamically stable,
not at an immediate risk of rupture and for whom the diameter is greater than 4-6cm.
Now in this patient, the atheroembolic require that the event be emergently done not electively.
Now let’s review some high-yield facts.
Aortic aneurysms, that a dilation of the aorta and generally it’s caused by a combination of aortic wall abnormalities,
that is dysfunctional elastin or collagen within the wall and also hemodynamics, you know, having hypertension.
Now an aortic aneurysm can be seen in the aortic root, the thoracic root, or the abdominal aorta.
Important for you to know, abdominal aortic aneurisms are by far the most common.
Now the complication here is an aortic rupture which of course can lead to death
and the main risk factors for an aortic aneurism is your older age, being male, having a smoking history and having hypertension.
And you can diagnose aortic aneurysms with either ultrasound or a CT
and the need for repair really depends on the size of the aneurysm, greater than 5.5 cm
or growing greater than 1 cm per year or the presence or absence of associated symptoms.