Renal complications and therapy in the PICU: hypertension, CKD, AKI, and RRT

The effect of continuous venovenous hemodiafiltration on amino acid delivery, clearance, and removal in children

BACKGROUND

In critically ill children with acute kidney injury (AKI), continuous kidney replacement therapy (CKRT) enables nutrition provision. The magnitude of amino acid loss during continuous venovenous hemodiafiltration (CVVHDF) is unknown and needs accurate quantification. We investigated the mass removal and clearance of amino acids in pediatric CVVHDF.

METHODS

This is a prospective observational cohort study of patients receiving CVVHDF from August 2014 to January 2016 in the pediatric intensive care unit (PICU) of a tertiary children's hospital.

RESULTS

Fifteen patients (40% male, median age 2.0 (IQR 0.7, 8.0) years) were enrolled. Median PICU and hospital lengths of stay were 20 (9, 59) and 36 (22, 132) days, respectively. Overall survival to discharge was 66.7%. Median daily protein prescription was 2.00 (1.25, 2.80) g/kg/day. Median daily amino acid mass removal was 299.0 (174.9, 452.0) mg/kg body weight, and median daily amino acid mass clearance was 18.2 (13.5, 27.9) ml/min/m², resulting in a median 14.6 (8.3, 26.7) % protein loss. The rate of amino acid loss increased with increasing dialysis dose and blood flow rate.

CONCLUSION

CVVHDF prescription and related amino acid loss impact nutrition provision, with 14.6% of the prescribed protein removed. Current recommendations for protein provision for children requiring CVVHDF should be adjusted to compensate for circuit-related loss. A higher resolution version of the Graphical abstract is available as Supplementary information.

A simple technique to achieve vascular access for continuous venous-venous ultrafiltration in a toddler

Acute renal failure is associated with increased mortality in the Pediatric Intensive Care Unit. When anuric or oliguric renal failure occurs, the associated fluid overload may compromise respiratory function and has been shown to be associated with worse outcomes. Renal replacement therapy using continuous venous-venous hemofiltration (CVVH) allows for fluid, solute, and nitrogenous waste removal. However, large bore vascular access with placement of a double-lumen dialysis catheter is necessary to ensure effective flow rates to allow for CVVH. We present a technique to facilitate exchange of a 4 Fr double-lumen central venous catheter to an 8 Fr double-lumen dialysis catheter for CVVH in a 2-year-old toddler who developed acute renal failure following surgery for congenital heart disease. This technique may be particularly valuable in patients with associated conditions including fluid overload and coagulation disturbances which may increase the morbidity of vascular access techniques.