Bivalirudin use in an infant with persistent clotting on unfractionated heparin

Area of Science:

• Cardiology
• Pharmacology
• Pediatric Critical Care

Background:

• Heparin-induced thrombocytopenia (HIT) presents challenges in pediatric anticoagulation due to variable anti-thrombin levels.
• Direct thrombin inhibitors like bivalirudin offer an alternative with a more predictable mechanism of action.
• Bivalirudin's use is expanding in pediatrics for its anti-thrombin-independent properties.

Observation:

• A 2-month-old female with recurrent systemic thrombi despite unfractionated heparin infusion was treated with bivalirudin.
• Initial bivalirudin dosing at 0.1 mg/kg/h was increased to 0.58 mg/kg/h to achieve therapeutic activated partial thromboplastin time (aPTT) values.
• Therapeutic aPTTs were achieved, but the patient developed worsening renal impairment, drug accumulation, and sepsis.

Findings:

• Bivalirudin achieved therapeutic aPTTs in a pediatric patient with HIT.
• Worsening renal impairment led to bivalirudin accumulation and necessitated discontinuation.
• The patient ultimately succumbed to overwhelming sepsis.

Implications:

• Bivalirudin can be considered for pediatric HIT when heparin is ineffective or contraindicated.
• Careful monitoring for renal function and potential drug accumulation is crucial in pediatric bivalirudin therapy.
• Further research is needed to establish optimal dosing and safety profiles for bivalirudin in neonates and infants.