Treatment of Pulmonary Embolism in ESRD Patients on Hemodialysis
In patients with End-Stage Renal Disease (ESRD) on hemodialysis who develop pulmonary embolism (PE), unfractionated heparin (UFH) is the recommended initial anticoagulant due to its predictable clearance and ability to be monitored in renal dysfunction. 1
Initial Anticoagulation Strategy
High-Risk PE (with hemodynamic instability)
- Immediate intravenous UFH should be initiated without delay with an 80 U/kg bolus followed by 18 U/kg/h continuous infusion 1
- Target aPTT should be 1.5-2.5 times normal (corresponding to anti-Xa activity of 0.3-0.6 IU) 1
- Adjust UFH dosing according to weight-based nomogram with first aPTT check at 4-6 hours after initiation 1
- Thrombolytic therapy should be considered in patients with cardiogenic shock and/or persistent arterial hypotension 1
- Surgical pulmonary embolectomy may be considered when thrombolysis is contraindicated or has failed 1
Non-High-Risk PE (hemodynamically stable)
- UFH remains the anticoagulant of choice in ESRD patients due to severe renal dysfunction 1
- Initial UFH therapy should be continued for at least 5 days 1
- Transition to vitamin K antagonists (VKAs) should occur only after achieving target INR levels for at least 2 consecutive days 1
UFH Dosing Adjustment Protocol
| aPTT | Adjustment |
|---|---|
| <35 s (<1.2× normal) | 80 U/kg bolus; increase rate by 4 U/kg/h |
| 35-45 s (1.2-1.5× normal) | 40 U/kg bolus; increase rate by 2 U/kg/h |
| 46-70 s (1.5-2.3× normal) | No change |
| 71-90 s (2.3-3.0× normal) | Decrease rate by 2 U/kg/h |
| >90 s (>3.0× normal) | Stop infusion for 1 h, then decrease rate by 3 U/kg/h |
| [1] |
Long-Term Anticoagulation
- Vitamin K antagonists (VKAs) are the preferred long-term anticoagulant for ESRD patients on hemodialysis 1
- Target INR should be 2.0-3.0 (target 2.5) 1
- Duration of anticoagulation depends on whether PE was provoked or unprovoked, with a minimum of 3-6 months 1
- LMWH should generally be avoided for long-term use in ESRD due to bioaccumulation, though some studies suggest it may be safe during hemodialysis sessions specifically 2
Special Considerations in ESRD Patients
- ESRD patients have both increased bleeding risk and thrombotic risk, requiring careful monitoring 3
- Peritoneal dialysis patients may have a higher risk of PE than hemodialysis patients 3
- PE can occur as a complication of arteriovenous fistula thrombosis and thrombolysis procedures 4, 5
- Regular monitoring of anti-Xa levels may be necessary in cases where aPTT is unreliable 1
- Direct oral anticoagulants (DOACs) are generally not recommended in ESRD patients due to limited data and concerns about drug accumulation 1
Monitoring and Follow-up
- Frequent aPTT monitoring is essential during UFH therapy to maintain therapeutic anticoagulation 1
- Platelet count should be monitored to detect heparin-induced thrombocytopenia 1
- When transitioning to VKAs, overlap with UFH for at least 5 days and until INR is therapeutic for 2 consecutive days 1
- Regular assessment of bleeding risk throughout treatment is crucial 1
Pitfalls and Caveats
- Avoid LMWH for initial treatment of PE in ESRD patients due to unpredictable pharmacokinetics and bioaccumulation 1
- Avoid aggressive fluid challenges in PE patients with right ventricular dysfunction 1
- Be cautious with thrombolysis in ESRD patients due to increased bleeding risk; reserve for high-risk PE with hemodynamic compromise 1
- Recognize that ESRD patients may have atypical presentations of PE due to comorbidities 3
- Consider that PE may occur as a complication of arteriovenous access thrombosis and thrombolysis procedures 4, 5