2.3 MTB Step 3 - General (Ischemia - Acute Mesenteric Ischemia, Ischemic Colitis, Chronic Mesenteric Ischemia, MALS)

Question 1

GENERAL

What are (4) General Considerations when you suspect Abdominal Ischemia?

Answer 1

1. Consider Acute Mesenteric Ischemia (in Older patients)
2. Consider Arrhythmia (A-Fib)
3. Consider Coronary Artery Disease (CAD)
4. Consider Recent Myocardial Infarction (MI)

Question 2

GENERAL

BASIC SCIENCE CORRELATE

1. Where do the Major Gastrointestinal Arteries that supply the Intestine arise from?
2. How many Major GI Arteries supply the Intestine?
3. What are the Names of the Major GI Arteries that supply the Intestine?

Answer 2

1. Abdominal AORTA
2. THREE Major GI Arteries
3. Names:
   
   • Celiac Axis
   • Superior Mesenteric Artery (SMA)
   • Inferior Mesenteric Artery (IMA)

Question 3

ACUTE MESENTERIC ISCHEMIA (AMI)

PRESENTATION

What is the Classical Presentation of Acute Mesenteric Ischemia (AMI)?

Answer 3

Mesenteric Angina

• AMI causes Mesenteric Angina.
• Mesenteric Angina = Postprandial Abdominal Pain that is Out of Proportion to the Exam

Question 4

ACUTE MESENTERIC ISCHEMIA (AMI)

DIAGNOSIS

How is Acute Mesenteric Ischemia (AMI) diagnosed?

Answer 4

Clinically

• Abdominal pain out of proportion to the exam.

Also, on Labs:

• Look for Acidosis
• Look for signs of Sepsis

Question 5

ACUTE MESENTERIC ISCHEMIA (AMI)

TREATMENT

If Acute Mesenteric Ischemia (AMI) is suspected what are the (2) possibilities considered the Next BEST Step in Management?

Answer 5

Surgery

or

Abdominal Angiography

Question 6

ACUTE MESENTERIC ISCHEMIA (AMI)

TREATMENT

1. If the Diagnosis of Acute Mesenteric Ischemia (AMI) is made during Surgery, what should you do next?
2. If the Diagnosis of Acute Mesenteric Ischemia (AMI) is made during Abdominal Angiography, what should you do next?

Answer 6

1. Embolectomy and Revascularization or Resection
2. Vasodilators or Thrombolytics

Question 7

ACUTE MESENTERIC ISCHEMIA (AMI)

BASIC SCIENCE CORRELATE

What is the Most Common Vessel affected in Acute Mesenteric Ischemia (AMI) and why?

Answer 7

Superior Mesenteric Artery (SMA)

due to the acuity of its angle and because it is a direct branch off the aorta

Question 8

ISCHEMIC COLITIS

DIAGNOSIS

What is the Best INITIAL and Most ACCURATE Test for Ischemic Colitis and what does it show?

Answer 8

CT Abdomen

shows Thickening of the Bowel in a Segmental pattern.

Question 9

ISCHEMIC COLITIS

TREATMENT

What are the (2) Treatments considered the Mainstays of Therapy for Ischemic Colitis?

Answer 9

1. IV Fluids - IVFs restore adequate Bowel Perfusion
2. Bowel Rest

Add Antibiotics for patients presenting with Ischemic Colitis + Fever

Question 10

CHRONIC MESENTERIC ISCHEMIA

ETIOLOGY

What is Chronic Mesenteric Ischemia usually the result of?

Answer 10

Chronic Mesenteric Ischemia is usually the result of Longstanding Atherosclerotic disease of 2 or more Mesenteric Vessels.

Question 11

CHRONIC MESENTERIC ISCHEMIA

MOA

What is the Mechanism of Abdominal Pain for Mesenteric Ischemia?

Answer 11

• Upon eating, the patient’s intestinal demand from oxygen is unmet because of atherosclerotic obstruction of blood flow.
• This causes excruciating pain and thus yields a patient with pain-induced anorexia.
• It is analogous to angina of the heart but affects only the gut.

Question 12

CHRONIC MESENTERIC ISCHEMIA

DIAGNOSIS

What Diagnostic Test for Chronic Mesenteric Ischemia is also Therapeutic?

Answer 12

Abdominal Angiography

Surgical correction requires, first, Abdominal Angiography to delineate the location of the Lesions, and then Stenting or Bypass to reestablish Blood Flow.

Question 13

MEDIAN ARCUATE LIGAMENT SYNDROME (MALS)

PRESENTATION

What is a common Presentation of Median Arcuate Ligament Syndrome (MALS)?

Answer 13

• MALS presents similarly to Chronic Mesenteric Ischemia (excruciating postprandial abdominal pain yielding pain-induced anorexia) but this is usually AFTER a recent Dramatic Weight Loss.

Question 14

MEDIAL ARCUATE LIGAMENT SYNDROME (MALS)

ETIOLOGY

What is the Pathophysiologic cause of Median Arcuate Ligament Syndrome (MALS)?

Answer 14

MALS is caused by External Compression of the Celiac Trunk by the Median Arcuate Ligament or the Celiac Ganglion.

MALS presents similar to CMI after dramatic weight loss, however, CMI is caused by Atherosclerotic Disease)

Question 15

MEDIAL ARCUATE LIGAMENT SYNDROME (MALS)

DIAGNOSIS

How is the diagnosis of Median Arcuate Ligament Syndrome (MALS) confirmed?

Answer 15

Abdominal Duplex Ultrasound

(measures Blood Flow through the Celiac Artery)

Blood Flow Velocity > 200 cm/s is suggestive of Celiac Artery Stenosis associated with MALS.

Question 16

MEDIAL ARCUATE LIGAMENT SYNDROME (MALS)

TREATMENT

What is the general approach to the treatment of Median Arcuate Ligament Syndrome (MALS)?

Answer 16

Surgical Decompression

of the

Celiac Artery