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Put any two — or three — conditions side by side, adult or pediatric, to spot the look-alike differences fast, row by row.

Aortic Dissection

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In one line

·A tear in the innermost layer of the aorta (the smooth lining) allows blood to split the wall into two channels—one true, one false—and that false channel can block the arteries feeding your brain, heart, kidneys, intestines, and legs.

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Normal physiology

·The aortic wall has three layers: the intima (smooth inner lining), media (muscular middle layer), and adventitia (tough outer coat). High-pressure pulsatile blood flow from the left ventricle (main pumping chamber) travels through the intact inner channel. Keep this picture in mind, because every unusual finding in dissection makes sense only as a change from this normal structure.

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What goes wrong

·Usually one upstream event—a tear in the intima—explains every downstream finding together.

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Hallmark signs

·Sudden severe tearing or ripping chest pain, often shooting straight through to the back or between the shoulder blades
·Blood pressure or pulse difference of 20 points or more between the two arms (or between an arm and a leg)
·Fainting (Syncope) (sudden fainting—you black out for a few seconds)
·One-sided weakness, trouble speaking, or sudden vision loss (stroke signs)
·Sudden trouble breathing, crackling sounds in the lungs, and low oxygen (acute heart failure)
·Severe constant belly pain, often with a high lactate level in the blood
·Very little urine (less than half a milliliter per kilogram of body weight per hour) or a rising creatinine (kidney-injury marker)
·Cold, pale leg with no pulse (acute limb starved blood flow (ischemia))

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Red flags · escalate now

·Sudden severe tearing chest or back pain with a blood-pressure difference of 20 points or more between the arms
·Fainting, new one-sided weakness, trouble speaking, or stroke signs in someone with chest pain
·Sudden heart failure, very low blood pressure, or signs that fluid is squeezing the heart (muffled heart sounds, neck veins bulging, low blood pressure) along with chest pain
·Severe belly pain with a high lactate level or signs the intestines are dying
·Cold leg with no pulse, or sudden kidney injury, in someone with sudden chest pain

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Workup

·CT angiography of the chest, abdomen, and pelvis with intravenous contrast
·Transthoracic echocardiography (ultrasound of the heart through the chest wall) or transesophageal echocardiography (ultrasound probe passed into the esophagus behind the heart)
·D-dimer blood test
·Electrocardiogram (ECG or EKG)
·Chest X-ray (posteroanterior and lateral views)
·Serum creatinine and blood urea nitrogen (BUN)
·Serum lactate

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Treatment

·Intravenous esmolol or labetalol to reduce heart rate to 60 beats per minute or lower
·Intravenous nicardipine, clevidipine, or nitroprusside (after beta-blocker is started) to lower systolic blood pressure to 100–120 mmHg
·Intravenous morphine or fentanyl for pain control
·Emergency open surgical repair (sternotomy and cardiopulmonary bypass) for Stanford Type A dissection (any involvement of the ascending aorta)
·Thoracic endovascular aortic repair (TEVAR) for complicated Type B dissection (descending aorta only) with malperfusion, uncontrolled pain, uncontrolled blood pressure, or enlarging aortic diameter
·Long-term beta-blocker therapy (metoprolol, atenolol, or carvedilol) plus additional blood pressure medicines (ACE inhibitors such as lisinopril, or angiotensin receptor blockers such as losartan) targeting blood pressure less than 120/80 mmHg, with serial CT or MRI imaging every 3–6 months for the first year, then every 6–12 months
·Avoid aortic valve replacement with a mechanical valve if the native valve can be repaired or if a tissue valve can be used instead, especially in patients with ongoing dissection in the descending aorta

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NCLEX trap

·Slow the heart rate FIRST with IV esmolol or labetalol to keep it under 60 beats per minute. Then lower blood pressure. In aortic dissection (a tear in the wall of the body's largest artery), lowering pressure before slowing the heart makes the tear grow faster because each strong pulse still pushes hard on the weakened wall.
·Aortic dissection can block the coronary arteries (vessels that feed the heart muscle) and raise troponin. Blood thinners and antiplatelet drugs make the dissection bleed more. Get imaging first. In aortic dissection, blood thinners are dangerous and can kill the patient.
·Unequal blood pressures in a patient with sudden tearing back pain means aortic dissection has blocked one of the branch arteries. This is an emergency. The tear is growing with every heartbeat and can rupture at any moment.
·In aortic dissection, stroke happens because the tear blocked the carotid artery (vessel to the brain), not because of a clot. Thrombolytic therapy will make the dissection bleed inside and can cause death. Get CT angiography (imaging that shows blood vessels) first. Thrombolytics are deadly in aortic dissection.
·Widened mediastinum in a patient with severe tearing chest pain radiating to the back is aortic dissection until proven otherwise. Blood in the false lumen (the new channel created by the tear) pushes the structures apart. Get a CT angiography right now, not antibiotics.
·Type B uncomplicated dissection can be managed with blood pressure and heart rate medicines only. Type B complicated (rupture, malperfusion meaning organs not getting enough blood, or growth on follow-up imaging) needs TEVAR (stent placed inside the aorta) right now. Do not assume Type B is safe without imaging proof that it is not growing or rupturing.

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