In an adult with sudden severe abdominal or back pain, possible pulsatile abdominal mass, hypotension, signs of organ malperfusion, and risk factors such as hypertension, connective‑tissue disease, or recent aortic instrumentation, how should I diagnose and initially manage a suspected abdominal aortic dissection?

Dissection Aortic Abdominal: Diagnosis and Initial Management

Immediate Diagnostic Approach

In a patient with sudden severe abdominal or back pain and suspected abdominal aortic dissection, immediately transfer to an intensive care unit and obtain urgent CT angiography while simultaneously initiating aggressive hemodynamic control—do not delay treatment waiting for imaging confirmation. 1, 2

Clinical Recognition

• Suspect abdominal aortic dissection in patients presenting with sudden, severe abdominal or back pain described as "tearing" or "ripping," particularly with hypertension, connective tissue disorders, or recent aortic instrumentation 1, 3, 4
• Note that approximately 6.4% of patients may present without pain, making diagnosis particularly challenging 1
• Examine for pulse deficits between extremities, signs of organ malperfusion (acute kidney injury, intestinal ischemia, limb ischemia), hypotension, or pulsatile abdominal mass 1, 2
• Isolated abdominal aortic dissection occurs in only 1.3% of acute type B dissections when the intimal flap originates at or below the renal arteries 1

Diagnostic Imaging Strategy

CT angiography is the first-line imaging modality for suspected abdominal aortic dissection in hemodynamically stable patients, with sensitivity and specificity exceeding 90%. 1, 2, 5

• In hemodynamically unstable patients, consider bedside transthoracic echocardiography or transesophageal echocardiography as first-line techniques depending on local expertise and availability 1, 5
• Avoid using multiple imaging modalities sequentially, as this causes unnecessary time loss and delays definitive treatment 1
• The diagnostic goals include: confirming diagnosis, classifying dissection extent, differentiating true from false lumen, localizing intimal tears, assessing side branch involvement, and detecting extravasation 1

Laboratory Testing

• Obtain D-dimer levels immediately—values below 500 ng/mL make aortic dissection unlikely 1
• Draw blood for cardiac biomarkers, complete blood count, lactate dehydrogenase, and renal function, but do not delay imaging while awaiting results 1, 6
• The ADD-RS (aortic dissection detection-risk score) combined with D-dimer has excellent capacity to rule out acute aortic syndrome 1

Immediate Medical Management

Initiate intravenous beta-blockers immediately as first-line therapy before any other intervention, targeting heart rate ≤60 beats per minute and systolic blood pressure <120 mmHg. 1, 6, 2

Hemodynamic Control Protocol

• Labetalol is the preferred first-line agent due to its combined alpha- and beta-blocking properties 1, 2
• Alternative beta-blockers include esmolol (preferred for its ultra-short half-life allowing rapid titration), propranolol, or metoprolol 6, 2
• If beta-blockers are contraindicated, use intravenous non-dihydropyridine calcium channel blockers (e.g., diltiazem) for heart rate control 1, 2

Blood Pressure Management Algorithm

• Step 1: Achieve heart rate ≤60 bpm with beta-blockers first 1, 6
• Step 2: If systolic BP remains >120 mmHg despite adequate beta-blockade, add intravenous vasodilators such as sodium nitroprusside or nicardipine 1, 2
• Critical caveat: Never administer vasodilators before beta-blockade, as this causes reflex tachycardia and increases aortic wall shear stress 2, 5
• In cases of malperfusion syndrome, tolerate higher blood pressure (potentially >120 mmHg) to optimize perfusion to threatened organs 1, 2

Monitoring Requirements

• Place an arterial line immediately for invasive blood pressure monitoring 1, 2
• Establish continuous three-lead ECG monitoring 2
• Monitor urine output, neurological status, and signs of organ malperfusion continuously 6

Critical Contraindications

Absolutely avoid thrombolytics, antiplatelet agents, and anticoagulation in suspected aortic dissection, even if ECG shows ischemic changes, as these cause hemorrhage into the dissection. 6

• Aortic dissection can involve coronary arteries (particularly the right coronary artery) and mimic acute myocardial infarction 1, 3
• The mortality rate is 1-2% per hour in untreated patients, making rapid diagnosis critical 6, 4

Pain Management

• Administer morphine sulfate for pain control, which also reduces sympathetic stimulation and helps lower blood pressure 2, 5

Definitive Management Considerations

• Obtain urgent surgical consultation immediately upon diagnosis 2
• Abdominal aortic dissection typically represents extension of type B dissection and is initially managed medically unless complications develop 2
• Emergency intervention (preferably endovascular repair) is indicated for: malperfusion syndrome, intractable pain despite medical therapy, rapidly expanding aortic diameter, periaortic hematoma, or inability to control blood pressure 2, 5

Common Pitfalls to Avoid

• Do not perform pericardiocentesis as an initial therapeutic step before surgery in patients with cardiac tamponade, as reducing intrapericardial pressure may cause recurrent bleeding 1
• Do not delay transfer to a specialized center with interventional and surgical backup while pursuing extensive diagnostic workup 1
• Do not administer vasopressors in hypotensive patients if possible, as they may propagate false lumen extension—consider volume administration first 5
• Do not obtain routine chest radiography in unstable patients, as this delays definitive treatment despite being abnormal in 60-90% of cases 2