A Hierarchical End Point Analysis of the Worldwide Exploration of Renal Replacement Outcomes Collaborative in Kidney Disease (WE ROCK) Cohort.

KEY POINTS: Early trial of liberation from continuous renal replacement therapy was associated with improved patient-important clinical outcomes in children with preserved urine output. Hierarchical composite end point analysis demonstrated greater intensive care unit and hospital-free days among patients who underwent a liberation trial. These findings supported early assessment of readiness for liberation using urine output to guide decision making for children receiving continuous renal replacement therapy.

BACKGROUND

Data to guide assessment of readiness for liberation from continuous renal replacement therapy (CRRT) in children are limited, and hierarchical composite end points have not been applied in this setting. We evaluated whether performing a trial of CRRT liberation among patients with preserved urine output is associated with improved outcomes using a hierarchical end point approach.

METHODS

We conducted a retrospective cohort study of patients aged≤25 years from the multicenter Worldwide Exploration of Renal Replacement Outcomes Collaborative in Kidney Disease registry. Patients with urine output >0.5 ml/kg per hour for≥24 hours within the first 5 days after CRRT initiation were included. The primary exposure was a trial of CRRT liberation by day 5. The primary outcome was a hierarchical composite of: ( 1 ) 90-day mortality, ( 2 ) 90-day KRT dependence, ( 3 ) intensive care unit-free days, and ( 4 ) hospital-free days. Inverse probability weighting was used to balance baseline characteristics, and outcomes were compared using a win ratio analysis.

RESULTS

Among 366 eligible patients, 192 (53%) underwent a liberation trial by day 5. These patients were older, had higher reference serum creatinine levels, and exhibited lower illness severity when compared with those who did not undergo a trial of liberation. In adjusted analyses, a liberation trial was associated with an improved hierarchical outcome (win ratio, 2.14 [95% confidence interval, 1.56 to 2.94], P < 0.001), driven primarily by greater intensive care unit- and hospital-free days.

CONCLUSION

Among CRRT recipients with preserved urine output, a trial of liberation by day 5 was associated with improved outcomes, supporting the early assessment of liberation readiness in patients with a urine output >0.5 ml/kg per hour.