What is the recommended anticoagulation method for pediatric patients undergoing Continuous Renal Replacement Therapy (CRRT)?

Anticoagulation for Pediatric Continuous Renal Replacement Therapy (CRRT)

For pediatric patients undergoing CRRT, regional citrate anticoagulation is suggested as the preferred method when there are no contraindications, though the choice should be guided by patient characteristics, local expertise, and available monitoring capabilities. 1

Anticoagulation Options for Pediatric CRRT

Regional Citrate Anticoagulation

• Regional citrate anticoagulation is suggested as the preferred option for CRRT in pediatric patients who do not have contraindications for citrate 1
• Citrate significantly prolongs circuit survival time compared to heparin (median 45.2 hours vs 21 hours), which increases CRRT efficiency in small children 2
• Citrate anticoagulation has been demonstrated to be safe and effective in children with body weights as low as 15 kg when using integrated citrate software and commercially available solutions 3
• Sufficient citrate clearance to prevent toxic accumulation can be achieved by convective clearance (CVVH) alone; diffusive clearance (CVVHDF) is not mandatory 4

Important Considerations for Citrate Use

• Monitoring should include evaluation of anticoagulant effect, filter efficacy, circuit life, and complications 1
• Regular assessment of post-filter and serum-ionized calcium should be performed to appropriately titrate the dose of citrate and calcium replacement solutions 1
• Monitoring of systemic acid-base balance is advisable in patients at high risk for citrate accumulation 1
• Potential complications include metabolic alkalosis, though studies show citrate toxicity is rare when properly monitored 2, 5

Heparin Anticoagulation

• For patients with contraindications to citrate, unfractionated or low-molecular-weight heparin is suggested 1
• Heparin anticoagulation requires monitoring of activated clotting times (ACT) or systemic partial thromboplastin time (PTT) 1
• Routine measurement of platelets should be performed to monitor for heparin-induced thrombocytopenia 1

No Anticoagulation Option

• In patients who are auto-anticoagulated or at high risk of bleeding, CRRT can be carried out without anticoagulation, although circuit life may be less than 24 hours 1

Clinical Decision Algorithm

1. Assess bleeding risk:

   • If patient has no increased bleeding risk or impaired coagulation → Consider anticoagulation 1
   • If patient has increased bleeding risk → Consider regional citrate or no anticoagulation 1

2. Evaluate for citrate contraindications:

   • Severe liver dysfunction (may impair citrate metabolism)
   • Severe shock with muscle hypoperfusion
   • If contraindications present → Use heparin or no anticoagulation 1

3. Consider local factors:

   • Availability of monitoring capabilities
   • Staff experience with citrate protocols
   • Availability of appropriate citrate solutions 1

Important Caveats and Pitfalls

• In the United States, citrate is not FDA-approved as an anticoagulant for CRRT, and commercially available citrate solutions are hypertonic, which may increase the risk of metabolic complications 1
• Standardized citrate administration and monitoring protocols are essential for safe implementation 1
• Danaparoid, fondaparinux, and hirudin are all renally excreted with extended half-lives in AKI and have no specific antidote - use with caution 1
• For patients with heparin-induced thrombocytopenia (HIT), direct thrombin inhibitors (such as argatroban) or Factor Xa inhibitors should be used 1
• Argatroban has been used at doses ranging between 0.7 and 1.7 μg/kg/min as anticoagulation for CRRT in patients with HIT 1
• Recent comparative studies show that nafamostat mesilate (commonly used in Japan and Korea) may provide similar filter life to citrate with comparable safety profiles 6