A disadvantage of continuous renal replacement therapy with hemofiltration in the treatment of acute renal failure is that

• A. Increased risk of infection
• B. Constant heparinization during therapy is required
• C. Requires elevated dialysate flow rates
• D. Can cause hypothermia only in adults

Answer: (B)

Continuous renal replacement therapy with hemofiltration relies on an extracorporeal circuit that can clot if blood is not adequately anticoagulated, so ongoing systemic heparinization is typically required to keep the circuit patent. This introduces a clear disadvantage: the need for continuous anticoagulation raises the risk of bleeding and related complications, and it requires careful monitoring and adjustment, especially in patients who are already hemodynamically unstable or at high bleeding risk.

Infection risk is a concern with any indwelling catheter and extracorporeal circuit, but it is not the defining challenge of this therapy. The requirement for anticoagulation is the key issue that differentiates this modality. Elevated dialysate flow rates are not a requirement for hemofiltration and are not the primary limitation. Hypothermia is a potential concern with CRRT as a whole and is not restricted to adults—it can occur in children as well.