What is the inpatient management and treatment plan for pulmonary embolism (PE)?

Inpatient Management and Treatment of Pulmonary Embolism

Immediate Anticoagulation

Start anticoagulation immediately upon suspicion of PE, even before diagnostic confirmation is complete, in patients with intermediate or high clinical probability. 1

Anticoagulation Options for Hemodynamically Stable Patients:

For most hemodynamically stable inpatients, initiate treatment with either a DOAC (apixaban or rivaroxaban as single-drug regimens) or LMWH/fondaparinux followed by oral anticoagulation. 1

DOAC Regimens (Preferred):

• Apixaban: 10 mg PO twice daily for 7 days, then 5 mg twice daily 2
• Rivaroxaban: 15 mg PO twice daily for 21 days, then 20 mg once daily (take with food) 3
• Edoxaban or Dabigatran: Require LMWH lead-in for at least 5 days before starting 1

LMWH/Fondaparinux Regimens:

• Enoxaparin: 1.0 mg/kg SC every 12 hours OR 1.5 mg/kg SC once daily 1
• Tinzaparin: 175 IU/kg SC once daily 1
• Fondaparinux: Weight-based dosing (5 mg if <50 kg, 7.5 mg if 50-100 kg, 10 mg if >100 kg) SC once daily 1

Anticoagulation for Hemodynamically Unstable/High-Risk PE:

Use unfractionated heparin (UFH) for patients with hemodynamic instability, those being considered for thrombolysis, or those with severe renal impairment (CrCl <30 mL/min). 1

• UFH dosing: 80 U/kg IV bolus, then 18 U/kg/hour continuous infusion 1
• Monitor aPTT and adjust to maintain 1.5-2.3 times control (46-70 seconds) 1

Risk Stratification

All patients must be stratified based on hemodynamic stability to determine treatment intensity. 1

High-Risk PE (Hemodynamically Unstable):

• Sustained hypotension (SBP <90 mmHg for ≥15 minutes)
• Requiring vasopressors
• Cardiogenic shock
• Cardiac arrest 1

Intermediate-Risk PE:

• Hemodynamically stable BUT with evidence of RV dysfunction (on echo or CT) or elevated cardiac biomarkers (troponin, BNP/NT-proBNP) 1

Low-Risk PE:

• Hemodynamically stable with no RV dysfunction or biomarker elevation
• PESI class I-II or sPESI = 0 1

Diagnostic Workup

Immediate Testing:

For suspected high-risk PE, obtain bedside echocardiography or emergency CTPA within 1 hour. 1

For suspected non-massive PE, obtain CTPA as the primary diagnostic test, ideally within 24 hours. 1

Essential Initial Laboratory Tests:

• D-dimer (only if low/intermediate clinical probability; do NOT order if high probability) 1
• Troponin (high-sensitivity troponin I or T) 1
• BNP or NT-proBNP 1
• Complete blood count (baseline for monitoring anticoagulation)
• Renal function (creatinine/eGFR to guide anticoagulant choice) 1
• Liver function tests 1
• Baseline coagulation studies (PT/INR, aPTT) 1

Imaging Studies:

• CTPA: Primary diagnostic modality; a negative CTPA in low/intermediate probability patients excludes PE 1
• Compression ultrasound of lower extremities: If positive for proximal DVT in a patient with suspected PE, confirms VTE and treatment can begin 1
• Echocardiography: For risk stratification in intermediate-risk patients or when CTPA unavailable in high-risk patients 1
• Chest X-ray: To exclude alternative diagnoses 1
• ECG: To assess for RV strain and exclude MI 1

Reperfusion Therapy for High-Risk PE

Administer systemic thrombolysis immediately for high-risk PE (hemodynamically unstable patients). 1

• Alteplase: 50 mg IV bolus (can be given on clinical grounds alone if cardiac arrest imminent) 1
• Do NOT routinely use thrombolysis for intermediate or low-risk PE 1

Rescue Interventions:

• Surgical pulmonary embolectomy: For patients with contraindications to thrombolysis or failed thrombolysis 1
• Catheter-directed therapy: Consider as alternative to surgery when thrombolysis contraindicated or failed 1

Monitoring and Supportive Care

Hemodynamic Monitoring:

• Continuous cardiac monitoring for high and intermediate-risk patients 1
• Serial vital signs every 4 hours minimum
• Oxygen supplementation to maintain SpO2 >90% 1

Laboratory Monitoring:

• Daily CBC to monitor for bleeding complications
• Renal function every 2-3 days if on LMWH/fondaparinux 1
• aPTT monitoring every 6 hours initially if on UFH, then daily once stable 1
• Platelet count on day 3-5 and day 7-10 to screen for heparin-induced thrombocytopenia 1

Repeat Risk Assessment:

• Reassess PESI/sPESI at 48 hours in intermediate-risk patients admitted to hospital; those reclassified as low-risk can be considered for early discharge 1
• Repeat echocardiography or biomarkers in those with initial RV dysfunction or biomarker elevation before discharge 1

Special Considerations

Contraindications to DOACs (Use VKA or LMWH instead):

• Severe renal impairment (CrCl <15-30 mL/min depending on agent) 1, 2, 3
• Antiphospholipid antibody syndrome 1
• Pregnancy or breastfeeding 1
• Active cancer (consider LMWH, though apixaban, edoxaban, rivaroxaban are alternatives) 1, 4

When to Use UFH Over LMWH:

• Hemodynamic instability (high-risk PE) 1
• Severe renal impairment (CrCl <30 mL/min) 1
• Severe obesity 1
• Primary reperfusion therapy planned (short half-life allows rapid reversal) 1

Transition to Oral Anticoagulation (if using VKA):

• Start warfarin on day 1 alongside parenteral anticoagulation 1
• Continue parenteral anticoagulation for minimum 5 days AND until INR 2.0-3.0 for two consecutive days 1
• Target INR 2.0-3.0 1

Duration of Anticoagulation

All patients require therapeutic anticoagulation for at least 3 months. 1, 4

• Provoked PE with major transient risk factor: Discontinue after 3 months 1, 4
• Unprovoked PE or persistent risk factors: Continue indefinitely 1, 4
• Active cancer: Continue indefinitely or until cancer cured 1, 4
• Recurrent VTE: Continue indefinitely 1

Criteria for Early Discharge/Outpatient Transition

Patients initially admitted with intermediate-risk PE (PESI class III) can be considered for early discharge when they meet low-risk criteria (PESI class I/II or sPESI = 0) at 48-hour reassessment. 1

Absolute Contraindications to Early Discharge:

• Hemodynamic instability 1
• Severe pain requiring opiates 1
• Active bleeding or high bleeding risk 1
• Severe renal impairment (CrCl <30 mL/min) or severe liver disease 1
• Social factors (inability to return home, inadequate care, lack of communication) 1
• Other medical comorbidities requiring hospitalization 1