What is the best approach for Venous Thromboembolism (VTE) prophylaxis in a 49-year-old bedbound man with End-Stage Renal Disease (ESRD) on Hemodialysis (HD), Type 2 Diabetes Mellitus (T2DM), Hypertension (HTN), Hypothyroidism, Peripheral Vascular Disease (PVD), Heart Failure with preserved Ejection Fraction (HFpEF), Morbid Obesity, Gastroesophageal Reflux Disease (GERD), Anemia, and multiple other comorbidities?

VTE Prophylaxis for a Bedbound Patient with ESRD on Hemodialysis and Multiple Comorbidities

For this 300 lb (BMI ~50) 49-year-old bedbound man with ESRD on hemodialysis and multiple comorbidities, unfractionated heparin (UFH) 5000 units subcutaneously every 8 hours is the recommended VTE prophylaxis regimen.

Risk Assessment

This patient has multiple risk factors for VTE:

• Bedbound status (immobility)
• Morbid obesity (BMI ~50)
• Heart failure with preserved ejection fraction
• Peripheral vascular disease
• Recent surgery (implied by wound dehiscence)
• Critical limb ischemia
• Infection (wound infection, gangrene)

These factors place him at high risk for VTE, making pharmacological prophylaxis essential 1.

Recommended Prophylaxis Regimen

First-line Recommendation

• Unfractionated heparin (UFH) 5000 units subcutaneously every 8 hours

This recommendation is based on:

1. The patient's ESRD status - UFH is preferred in severe renal impairment 1
2. The 2023 WSES guidelines specifically recommend "5000 U of UFH every 8 h in case of renal failure" for elderly trauma patients, which can be extrapolated to this high-risk patient 1
3. The patient's morbid obesity (Class 3 obesity) requires more frequent dosing to maintain adequate anticoagulation levels 1

Why Not LMWH?

Low molecular weight heparins (LMWHs) like enoxaparin are generally not recommended in ESRD patients on hemodialysis due to:

• Risk of drug accumulation and increased bleeding risk 2
• A retrospective study showed a concerning 6.8% major bleeding or clinically relevant non-major bleeding rate with enoxaparin in ESRD patients on hemodialysis 2

Why Not DOACs?

Direct oral anticoagulants (DOACs) are not recommended for this patient due to:

• Limited data in patients with severe renal impairment 1
• Lack of sufficient clinical data in patients with multiple comorbidities 1

Special Considerations

Obesity-Specific Considerations

For Class 3 obesity (BMI ≥40), the European Society of Cardiology recommends:

• More frequent monitoring for possible overdosing with UFH 1
• Careful aPTT monitoring 1

Renal Considerations

• ESRD on hemodialysis significantly impacts anticoagulant clearance
• UFH is preferred over LMWH in severe renal impairment as it has hepatic clearance rather than renal elimination 3

Mechanical Prophylaxis

• Intermittent pneumatic compression devices should be added to pharmacological prophylaxis given the patient's extremely high risk profile 1
• If pharmacological prophylaxis becomes contraindicated (e.g., active bleeding), mechanical prophylaxis should be continued 1

Monitoring Recommendations

1. Monitor for signs of bleeding (especially at surgical sites and stump)
2. Monitor platelet count for heparin-induced thrombocytopenia
3. Regular assessment of renal function during hospitalization
4. Careful monitoring of aPTT if therapeutic anticoagulation becomes necessary

Pitfalls to Avoid

1. Do not use fondaparinux - contraindicated in patients with creatinine >2 mg/dL (180 μmol/L) 4
2. Do not use standard prophylactic doses of LMWH - risk of accumulation and bleeding in ESRD 2
3. Do not use fixed twice-daily dosing of UFH - insufficient for this high-risk, morbidly obese patient 1
4. Do not overlook mechanical prophylaxis - should be used in conjunction with pharmacological methods in this high-risk patient 1

Duration of Prophylaxis

VTE prophylaxis should be continued throughout the entire period of immobility/hospitalization, with reassessment if the patient's mobility status improves.