Citrate clearance in children receiving continuous venovenous renal replacement therapy

Area of Science:

• Pediatric Nephrology
• Critical Care Medicine
• Pharmacology

Background:

• Anticoagulation is essential during continuous renal replacement therapy (CRRT) to prevent circuit clotting.
• Heparin is common, but regional citrate anticoagulation is preferred for bleeding-risk patients.
• Concerns exist about citrate toxicity, often necessitating diffusive clearance in CRRT.

Purpose of the Study:

• To evaluate citrate clearance and safety during CRRT in children using regional citrate anticoagulation.
• To determine if diffusive clearance is mandatory for preventing citrate toxicity in this population.

Main Methods:

• Five children received CRRT with citrate anticoagulation using a COBE PRISMA machine and AN-69 filter.
• Citrate was infused to maintain circuit ionized calcium <0.5 mmol/l; CaCl2 infused systemically.
• Convective clearance (CVVH) was used, with some patients transitioned to hemodiafiltration (CVVHDF).

Main Results:

• Mean filter life was 51 hours; 24 filters were changed due to clotting.
• Mean patient citrate levels were 0.69 mmol/l, with similar clearance to urea (31-38 ml/min per 1.73 m(2)).
• Citrate clearance remained stable when convective clearance was partially substituted with diffusive clearance.

Conclusions:

• Regional citrate anticoagulation is feasible, effective, and safe in pediatric CRRT.
• Convective clearance alone adequately clears citrate, preventing toxic accumulation.
• Diffusive clearance is not mandatory for citrate anticoagulation during CRRT in children.