Pre-Test: Peripheral Vascular Problems / DVS Flashcards
What are matrix metalloproteinases (MMPs) and what is their role in AAA formation?
MMPs are important for collagen turnover, which is vital to inflammation and wound healing. Patients with AAA have abnormally high levels of MMP activity in the aortic wall, which weakens the arterial wall and contributes to the dilation of the aneurysm over time.
For the first 6 hrs following a long and difficult surgical repair of a 7 cm AAA, a 70 y/o man has atotal urinary output of 25 mL since the operation. Which of the following is the most appropriate dx test to evaluate the cause of his oliguria?
a. Renal scan
b. Aortogram
c. Left heart preload pressures
d. Urinary sodium concentration
e. Creatinine clearance
c. Left heart preload pressures
By far the most likely cause of the oliguria observed in this patient is hypovolemia. Volume status would be best assessed by placing a Swan-Ganz catheter to measure the preload pressures in the LA. Patients who undergo long, difficult operations in large surgical fields collect third-space fluids and become intravascularly depleted despite large volumes of IV fluid and blood replacement.
Proper mgmt usually involves titrating the cardiac output by providing as much fluid as necessary to keep the wedge pressures near 15 mm Hg
A 60 y/o man is found on route exam to have a 3 cm pulsatile mass in the R popliteal fossa. What is the most appropriate mgmt of this pt?
a. Antiplatelet therapy
b. Anticoagulation
c. Thrombolytic therapy
d. Surgery
d. Surgery
The pt has a popliteal artery aneurysm. Popliteal artery aneurysms = most common peripheral arterial aneurysms and are bilateral in >50% of pts. Many pts are asymptomatic when diagnosed, but they can present with chronic limb ischemia or acute thromboembolism.
Unlike AAA, popliteral artery aneurysms RARELY RUPTURE. All symptomatic popliteal aneurysms should undergo surgical repair with exclusion of the aneurysm (which is ligated and left in situ) combined with a surgical bypass.
A 25 y/o woman presents to the ER complaining of redness and pain in her R foot up to the level of the midcalf. She reports that her R lower extremity has been swollen for at least 15 years, but her left leg has been normal. On physical exam, she has a temperature of 102.2, and the RLE is non-tender with nonpitting edema from the groin down to the foot. There is cellulitis of the R foot without ulcers or skin discoloration. The left leg is normal. Which of the following is the underlying problem?
a. Congenital lymphedema
b. Lymphedema praecox
c. Venous insufficiency
d. DVT
e. Acute arterial insufficiency
b. Lymphedema praecox
This pt’s underlying problem is unilateral primary lymphedema. Lymphedema is classified as primary when etiology is unknown. Hypoplasia of the lymphatic system of the lower extremity accounts for more than 90% of cases of primary lymphedema.
If edema is present at birth, it is referred to as congenital; if it starts early in life (as in this woman), it is called praecox; if it appears after age of 35 y/o, it is tarda.
The inadequacy of the lymphatic system accounts for the repeated episodes of cellulitis that the patients experience.
Swelling is NOT seen with acute arterial insufficiency
A 58 y/o man presents with pain in the left leg after walking more than one block that is relieved with rest. On exam, distal pulses are not palpable in the left foot and their is dry gangrene on the tip of his left fifth toe. An ABI on the same side is 0.5. Which of the patient’s symptoms or signs of arterial insufficiency qualifies him for reconstructive arterial surgery of the left lower extremity?
a. ABI < 0.7
b. Rest pain
c. Claudication
d. Absent palpable pulses
e. Toe gangrene
e. Toe gangrene
The major threat to patients with arterial occlusive disease is limb loss. Rest pain and gangrene represent advanced stages of arterial insufficiency and warrant arterial reconstructive surgery whenever clinically feasible. This patient does not have rest pain which is defined as persistent pain in the extremity.
A 60 y/o is admitted to the coronary care unit with a large anterior wall MI. On his second hospital day, he begins to complain of the sudden onset of numbness in his R foot and an inability to move his R foot. One xam, the R femoral, popliteal, and pedal pulses are no longer palpable. The left lower extremity is normal. Which of the following is the most appropriate mgmt of this patient?
a. Duplex imaging of the R lower extremity arteries
b. CT angiogram of the RLE
c. CT angiogram of b/l lower extremities
d. Embolectomy of the R femoral a
d. Embolectomy of the R femoral a
Immediate surgical intervention is the appropriate mgmt for pts presenting with acute arterial insufficiency with neurologic compromise of the lower extremities from thromboembolic disease.
The heart is the most common source of arterial emboli and accounts for 90% of cases. Sources include diseased valves, endocarditis, the LA in pts with unstable atrial arrhythmias, and mural thrombus on the wall of the LV in pts with MI.
Two days after admission to the hospital for an MI, a 65 y/o man complains of severe, unremitting midabdominal pain. His cardiac index is 1.6 Exam is remarkable for an absence of peritoneal irritation or distention despite the patient’s persistent complaint of severe pain. Serum lactate is 9 mmol/L (normal is < 3 mmol/L). Which of the following is the appropriate next step in this patient’s mgmt?
a. Perform CT
b. Perform mesenteric angiography
c. Perform laparoscopy
d. Perform flexible sigmoidoscopy to assess distal colon and rectum
b. Perform mesenteric angiography
Abdominal pain out of proportion to findings on exam is characteristic of intestinal ischemia (small intestine and R colon). The etiology of ischemia may be embolic or thrombotic occlusion of the mesenteric vessels or nonocclusive ischemia due to low cardiac index or mesenteric vasospasm.
Differentiation among these etiologies is best made by mesenteric angiography.
C. Non-contrast CT brain
Patients who present with symptoms concerning for stroke should undergo a non-contrast CT scan of the brain to r/o intracranial hemorrhage
Once hemorrhage has been ruled out, consideration should be given for thrombolytic therapy for an ischemic stroke (IV if within 3 h of symptom onset, intra-arterial if within 6 hr of onset).
Doppler U/S, CTA of neck may be useful to determine cause of the stroke (carotid plaque vs. cardioembolic), but they are not part of the acute mgmt of the pt
C.
The United States Preventive Services Task Force (USPSTF) recommends a one-time screening for AAA but U/S in men aged 65-75 that have any smoking hx.
There is no recommendations for women and men who have never smoked.
B.
The most likely etiology is a DVT given the swelling and hx of colon cancer (hypercoagulability).
Best dx test = venous duplex scan
An ABI is appropriate for suspected peripheral arterial disease (PAD), however, that would not cause swelling. CTA would be auseful f/u study for PAD prior to a planned intervention
A.
The patient has PAD, manifested by claudication, which is not immediately limb threatening. The dx is confiemd by the ABI < 0.9. Further testing is not necessary at this time to confirm the dx.
Additional imaging (B-D) should be reserved for pts in whom an intervention is being planned. Initial mgmt of claudication includes smoking cessation, a walking program, and modification of rsik factors (lipid-lowering agents, HTN control).
A. Labetolol
This pt is suffering from an ischemic stroke. Permissive HTN is considered beneficial following an ischemic stroke so as to maximize cerebral perfusion pressure (CPP).
For ischemic strokes, do not use antihypertensive medications to lower BP unless diastolic is greater than 120 or systolic greater than 220, to ensure proper cerebral perfusion.
Avoid nitroglycerin/nitroprusside, which can serve as potent vasodilators in cerebral arteries and veins, increasing ICP which can further compromise CPP (CPP = MAP-ICP)
C.
Buerger’s disease, also known as thromboangiitis obliterans, is a non-atherosclerotic vascular occlusive disease seen in young (<40), mostly male smokers. It predominantly involves arteries in the leg below the knee (popliteal and tibial arteries). It also causes venous thrombosis. The cause is unknown.
B.
This pt has ischemic rest pain and a nonhealing ulcer, both of which are manifestations of critical peripheral artery diseae (PAD) that are considered limb threatening. The pt will likely progress to an amputation unless blood flow is improved.
As such, the next step is to obtain arterial imaging of the lower extremities via CTA, MRA, or formal transfermoral arteriography in anticipation of either balloon angioplasty, stenting, or arterial bypass.
A.
Pt presents with classic case of venous stasis ulcer. Unna boot is a compressive gauze that contains zinc oxide and calamine to promote wound healing.
