0071643192.pdf

■ MRI

■ Good visualization, but limited utility in the ED

■ Aortography

■ The classic “gold standard,” but largely supplanted by CT angiography

TREATMENT

■ Goal (after resuscitation) is to decrease shearing forcesby reducing BP

and the rate of rise of the arterial pulse (dP/dT).

■ If hypotension present:

■ Intravenous fluids, pressors

■ Consider pericardiocentesis, if tamponade.

■ If systolic BP >120:

■ Start with IV b-blockers(esmololor labetalol drip).

■ Add IV nitroprusside, if needed.

■ Goal is systolic BP 100–120.

■ Avoid: Nifedipine.

■ Type A: Surgical repair

■ Type B: Admit to ICU for medical management.

■ Indications for OR: Rupture limb or organ ischemia, progression of

dissection, uncontrolled HTN

COMPLICATIONS

■ Free rupture through adventitia, nearly always fatal

■ Aortic regurgitation and CHF in proximal dissection

■ MI if coronary arteries involved

■ Tamponade if dissection ruptures into pericardium

■ CVA or paresis if carotid or spinal arteries involved

■ Limb or organ ischemia

Occlusive Arterial Disease

ACUTEARTERIALTHROMBOEMBOLISM

Arterial thromboembolism is a limb-threatening emergency that requires

rapid diagnosis and intervention. It often occurs in patients withoutchronic

atherosclerotic disease. Because such patients lack extensive collateral arterial

circulation, severe ischemia results.

PATHOPHYSIOLOGY

■ Thrombus forms in region of turbulent flow →embolus to distal artery.

■ Common sources of thrombus:

■ LV mural thrombusfollowing MI (most common)

■ Left atrial thrombusfrom mitral valve disease and atrial fibrillation

■ Mechanical valve

■ Mural thrombus from large arterial aneurysms

■ Most common sites of embolism:

■ Bifurcation of common femoral artery (#1)

■ Popliteal artery

SYMPTOMS/EXAM

■ Pain

■ Pallor

■ Paresthesias (indicates limb-threatening ischemia)

■ Pulselessness

CARDIOVASCULAR EMERGENCIES

Initial drug of choice in aortic

dissection is IV esmolol (or

labetalol)→decrease

shearing forces.

Inferior MI is the most

common injury pattern seen

in aortic dissection due to

involvement of the RCA.

Common sources of emboli

are cardiac in origin.

The most common site of

acute arterial embolism =

bifurcation of common

femoral artery.