Management and Treatment of Suspected Aortic Dissection
The management of suspected aortic dissection requires immediate anti-impulse therapy targeting systolic blood pressure between 100-120 mmHg and heart rate ≤60 beats/min using intravenous beta-blockers as first-line agents, followed by urgent diagnostic imaging with CT angiography and surgical consultation. 1
Initial Recognition and Assessment
Clinical Suspicion
- Use the Aortic Dissection Detection (ADD) score to assess probability 2
- High-risk features include:
- Acute onset of tearing/ripping chest or back pain
- Mediastinal/aortic widening on chest radiograph
- Pulse or blood pressure differentials (>20 mmHg between arms) 2
Immediate Actions
- Establish IV access and begin continuous ECG and blood pressure monitoring
- Measure blood pressure in both arms to detect differences
- Avoid unnecessary delays in obtaining definitive imaging 1
Medical Management
Blood Pressure and Heart Rate Control
First-line therapy: Intravenous beta-blockers
- Preferred agents: Labetalol, esmolol, propranolol, or metoprolol 1
- Target: SBP 100-120 mmHg and heart rate ≤60 beats/min
If additional BP control needed: Add vasodilators (only after beta-blockade)
- Options: Nicardipine, clevidipine, or sodium nitroprusside
- CAUTION: Never administer vasodilators before beta-blockers as this can worsen dissection by causing reflex tachycardia 1
Pain management: IV morphine sulfate, titrated to effect 1
Diagnostic Imaging
First-line Imaging
- CT angiography (CTA) with IV contrast (sensitivity and specificity >95%) 1
- Protocol should include non-contrast images first (to detect intramural hematoma)
- Imaging should extend from thoracic inlet to pelvis
- ECG-gating provides motion-free images of aortic root and coronary arteries
Alternative Imaging Options
- Transesophageal echocardiography (TEE) (sensitivity 99%, specificity 89%)
- Best for unstable patients who cannot be transported for CT 1
- Transthoracic echocardiography (TTE) (sensitivity 59-80%)
- Useful for initial bedside screening but insufficient for definitive diagnosis
- Do not rely on abnormal bedside TTE alone to establish diagnosis 2
- MRI (sensitivity and specificity approaching 100%)
- Reserved for stable patients with contrast allergy or renal dysfunction 1
Management Based on Dissection Type
Type A Dissection (Involving Ascending Aorta)
- Immediate surgical consultation for emergency aortic repair
- Transfer directly to operating room if diagnosis is confirmed 3
- Continue medical therapy to control heart rate and blood pressure en route to surgery
Type B Dissection (Involving Descending Aorta Only)
- Medical management is first-line for uncomplicated cases
- Surgical/endovascular intervention for complicated cases (malperfusion, rupture, refractory pain) 4
- Vascular surgery consultation for all Type B dissections
Transfer Considerations
- Transfer patients with high probability of aortic dissection (ADD score ≥1) to centers with:
- Direct admission to the operating room for confirmed cases can improve outcomes 3
Critical Pitfalls to Avoid
- Never administer thrombolytics or anticoagulants in suspected aortic dissection 2, 1
- Avoid aggressive fluid administration that could increase aortic wall stress 1
- Do not delay definitive imaging in patients with high clinical suspicion
- Never rely solely on clinical decision rules to rule out aortic dissection 2
- Do not perform pericardiocentesis in patients with cardiac tamponade due to aortic dissection as it may cause recurrent bleeding 1
Special Considerations
- For hemodynamically unstable patients with cardiac tamponade, consider immediate surgical intervention 1
- In cases with normal or low blood pressure, rule out volume depletion from blood sequestration in false lumen or pericardial/pleural spaces 1
- For patients with spinal ischemia or brain injury, maintain a higher mean arterial pressure 1