Aortic dissection

Score: one point for each category (conditions, pain, exam) with at least one feature, so 0 to 3 (ACC/AHA 2022 Table 24). ACC/AHA tiers: 0 low, 1 moderate, 2–3 high. ESC 2024: under 2 low risk, 2 or more high risk.

Blank is not normal: each category needs a tick or "None of these". If two categories are already positive, the score is at least 2 and the imaging step shows even with the third unanswered.

ADvISED (1,850 patients, 13% with AAS; D-dimer negative if under 500 ng/mL): D-dimer sensitivity 96.7%, specificity 64%. ADD-RS 0 with negative D-dimer: failure rate 0.3% (95% CI 0.1–1.9), efficiency 15.9%. ADD-RS 0–1 with negative D-dimer: failure rate 0.3% (95% CI 0.1–1.0), efficiency 49.9%. No rule-out was tested at ADD-RS 2–3.

ESC 2024 algorithm: ADD-RS 2 or more → CT without delay (focused TTE and ECG; TTE or TEE first if unstable). Under 2 → ECG to exclude STEMI, then chest X-ray, D-dimer and POCUS; any compatible finding → CT.

Unstable or shocked: if "Hypotension or shock" is ticked, the tool never offers the D-dimer or "unlikely" steps; ESC 2024 (Figure 30 footnote) puts bedside TTE or TEE first in unstable patients, then CT.

ADD-RS 1 with a negative D-dimer is a rule-out in ESC 2024 and ADvISED. ACC/AHA calls a score of 1 moderate risk and supports exclusion only with a low score plus a low D-dimer, so the tool flags it rather than showing green. A green result also needs a negative chest X-ray, which is part of the ESC algorithm; without it the result is labeled "ADvISED only".

Assay: labs report D-dimer in fibrinogen-equivalent units (FEU) or D-dimer units (DDU), with assay-specific cutoffs. Confirm your lab's unit type and cutoff before applying 500 ng/mL.

Rounding: D-dimer is shown as a whole number of ng/mL and is negative only if that number is under 500. µg/mL × 1000 = ng/mL. A value that looks like the other unit is held until you confirm it; tapping the other unit relabels the number instead of converting it.

ACC/AHA 2022 (Class 1): heart rate 60–80 bpm; SBP under 120 mm Hg or the lowest pressure that keeps end-organs perfused. IV beta-blocker first; IV diltiazem or verapamil if beta-blockers are contraindicated (Class 2a); add an IV vasodilator if BP stays high after the beta-blocker is started. Avoid vasodilators as initial therapy (reflex tachycardia). Arterial line, ICU, pain control.

ESC 2024 (Class I): heart rate 60 bpm or less and SBP under 120 mm Hg; keep MAP higher with spinal cord ischemia or brain injury, and tolerate higher pressure with malperfusion. Labetalol or esmolol first; vasodilator added once rate control is on board.

ESVS 2026 (European vascular), acute type B: SBP under 120 mm Hg and heart rate under 60 bpm, adjustable to maintain organ perfusion (Recommendation 36, Class I, LOE C). It warns that rapid lowering can cause renal, cardiac and cerebral ischemia.

Shock, or SBP under 90 mm Hg (a conventional hypotension threshold; AAS guidelines give no number): no anti-impulse step or dose is shown. Hypotension in AAS points to tamponade, rupture, acute severe aortic regurgitation or coronary involvement.

Esmolol (10 mg/mL vial and bag; 20 mg/mL double-strength bag): 500 mcg/kg over 1 min, then 50 mcg/kg/min; titrate at intervals of at least 4 min in 50 mcg/kg/min steps. Little added rate control above 200; hypertension may need 250–300; above 300 mcg/kg/min not studied. Maintenance infusions may continue up to 48 h. Contraindicated with severe sinus bradycardia, heart block beyond first degree, sick sinus syndrome, decompensated heart failure, cardiogenic shock, pulmonary hypertension, or IV verapamil given close by.

Labetalol: 20 mg over 2 min, then 40 or 80 mg every 10 min to a total of 300 mg; or 2 mg/min infusion. Usual effective total 50–200 mg.

Nicardipine: 5 mg/h, +2.5 mg/h every 5–15 min, maximum 15 mg/h; reduce to 3 mg/h at goal after rapid titration. 0.1 mg/mL: 50–150 mL/h. 0.2 mg/mL: 25–75 mL/h. Contraindicated in advanced aortic stenosis.

Clevidipine (0.5 mg/mL, about 0.2 g lipid per mL): 1–2 mg/h, double every 90 s early, then smaller steps every 5–10 min. Usual 4–6 mg/h; most patients 16 mg/h or less; limited experience to 32 mg/h. No more than 1,000 mL per 24 h — about 20.8 mg/h at 0.5 mg/mL; the label rounds this to an average of 21 mg/h. Contraindicated with soy or egg allergy, defective lipid metabolism, severe aortic stenosis.

Diltiazem, verapamil and nitroprusside are named but not dosed here. Educational — verify against your local protocol and pharmacist.