Continuous renal replacement therapy amino acid, trace metal and folate clearance in critically ill children

Purpose: We hypothesized continuous veno-venous hemodialysis (CVVHD) amino acid, trace metals and folate clearance impacts nutrient balance. Methods: Critically ill children receiving CVVHD were studied prospectively for 5 days. Blood concentrations (amino acids, copper, zinc, manganese, chromium, selenium and folate) were measured at CVVHD initiation, and Days 2 and 5. CVVHD clearance, losses and nutrient balances were calculated on Days 2 and 5. Results: We studied 15 children aged 7.7 +/- 6.7 years. Nitrogen balance was negative on Days 2 and 5. Amino acid clearances ranged from 2.8 to 51.1 ml/min per 1.73 m(2). CVVHD losses corresponded to 20% of intake. Days 2 and 5 balances were negative for selenium, but positive for other trace metals. Folate clearance was 16 ml/min per 1.73 m(2) on Days 2 and 5 and serum concentrations decreased significantly from initiation to Day 5 (P < 0.05). Conclusions: Nutrient losses by CVHHD may impact adequate nutrition provision.