Pulmonology / Emergency Medicine
Acute Pulmonary Embolism
Obstruction of pulmonary arteries by thrombus; management stratified by hemodynamic status and RV strain.
I26.99
I26.09
Reviewed 2026-08-30- SBP < 90 mmHg for > 15 min or vasopressor need = HIGH-RISK (massive) PE → systemic thrombolysisGRADE 1B
- Cardiac arrest with suspected PE: give thrombolysis during CPR
- RV dysfunction on echo/CT + raised troponin = intermediate-high risk → monitored bed
- Start anticoagulation immediately if high/intermediate pretest probability and no contraindicationGRADE 1A
- Apply Wells score → D-dimer (age-adjusted) if PE unlikelyGRADE 1A
- CT pulmonary angiography — gold standard imagingGRADE 1A
- V/Q scan if contrast allergy, severe CKD or pregnancy
- Bedside echo for RV dilatation in unstable patients
- Troponin, BNP, ECG (S1Q3T3, RV strain), lower limb compression US
Wells (PE)
≤ 4 PE unlikely → D-dimer · > 4 PE likely → CTPA
PERC
All 8 negative in low pretest → no further testing
sPESI
0 = low risk, consider outpatient · ≥ 1 = admit
- Hemodynamically stable: DOAC preferred over VKAGRADE 1B
- High-risk PE: UFH infusion + systemic alteplaseGRADE 1B
Apixaban
PO
- Adult
- 10 mg BID × 7 days, then 5 mg BID
- Renal
- Avoid if CrCl < 25 (limited data)
- Duration
- ≥ 3 months
Enoxaparin
SC
- Adult
- 1 mg/kg q12h
- Renal
- CrCl < 30: 1 mg/kg q24h
- Duration
- Bridge / cancer-associated
1/kg
Unfractionated heparin
IV
- Adult
- 80 U/kg bolus → 18 U/kg/h
- Renal
- No adjustment (preferred in severe CKD)
- Titration
- aPTT 1.5–2.5× control or anti-Xa 0.3–0.7
- Duration
- Until transition
Alteplase
IV
- Adult
- 100 mg over 2 h
- Renal
- No adjustment
- Duration
- Single dose
- Contraindication to thrombolysis: catheter-directed therapy or surgical embolectomy
- Contraindication to anticoagulation: retrievable IVC filter
- Pregnancy: LMWH throughout; DOACs and warfarin contraindicatedGRADE 1B
- Antiphospholipid syndrome (triple positive): warfarin, avoid DOACGRADE 1B
- Cancer-associated: DOAC (apixaban/edoxaban) or LMWH
- Continuous telemetry and SpO2 for 24–48 h if intermediate-high risk
- Watch for bleeding, recurrent VTE, decompensation (rising lactate, hypotension)
- Discharge when sPESI 0, stable on oral anticoagulation, follow-up arranged
- Review at 3 months: extended therapy if unprovoked; screen for CTEPH if dyspnea persists
- guidelineESC Guidelines for Acute Pulmonary Embolism — ESC/ERS, 2019
- guidelineAntithrombotic Therapy for VTE Disease — CHEST, 2021
- trialAMPLIFY: apixaban for acute VTE — NEJM, 2013
- trialPEITHO: tenecteplase in intermediate-risk PE — NEJM, 2014
- fda labelEliquis (apixaban) prescribing information — DailyMed, 2025
Decision support only. Verify against local protocols and current labeling.