Hyperammonemia and neonatal cardiac failure
T Adamovic1, P Jouvet, S Vobecky
1Department of Pediatrics, Sainte-Justine Hospital, University of Montréal, QC, Montréal, Canada.
Minerva Anestesiologica
|May 5, 2011
Summary
Severe hyperammonemia (hyperNH3) in neonates is rare, especially after cardiac surgery. This case shows multifactorial causes can overwhelm liver ammonia detoxification in infants with congenital heart disease.
Area of Science:
- Neonatal Medicine
- Pediatric Cardiology
- Gastroenterology
Background:
- Neonatal cardiac failure post-surgery presents unique challenges.
- Severe hyperammonemia (hyperNH3) is an uncommon complication in this population.
- Complex congenital heart disease requires multidisciplinary management.
Observation:
- A 37-week gestation infant with complex congenital heart disease developed severe hyperNH3 (467 µmol/L).
- The infant had truncus arteriosus type III, interrupted aortic arch, and tricuspid valve insufficiency.
- Despite elevated ammonia, liver function tests (INR 1.9) indicated no severe liver failure.
Findings:
- Multifactorial causes of hyperNH3 included a congenital porto-caval shunt limiting liver detoxification.
- Liver ischemia, high protein intake, and increased protein catabolism contributed to ammonia buildup.
- Treatment with protein restriction, phenylacetate, and sodium benzoate partially reduced ammonia levels.
Implications:
- Liver ammonia detoxification capacity is limited in neonates with multifactorial insults.
- Early recognition and management of hyperNH3 are crucial in critically ill neonates.
- This case underscores the interplay between cardiac function, liver perfusion, and ammonia metabolism.
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