Comparison of Urine Output among Patients Treated with More Intensive Versus Less Intensive RRT: Results from the Acute Renal Failure Trial Network Study.
BACKGROUND AND OBJECTIVES
Intensive RRT may have adverse effects that account for the absence of benefit observed in randomized trials of more intensive versus less intensive RRT. We wished to determine the association of more intensive RRT with changes in urine output as a marker of worsening residual renal function in critically ill patients with severe AKI.


DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS
The Acute Renal Failure Trial Network Study (n=1124) was a multicenter trial that randomized critically ill patients requiring initiation of RRT to more intensive (hemodialysis or sustained low-efficiency dialysis six times per week or continuous venovenous hemodiafiltration at 35 ml/kg per hour) versus less intensive (hemodialysis or sustained low-efficiency dialysis three times per week or continuous venovenous hemodiafiltration at 20 ml/kg per hour) RRT. Mixed linear regression models were fit to estimate the association of RRT intensity with change in daily urine output in survivors through day 7 (n=871); Cox regression models were fit to determine the association of RRT intensity with time to ≥50% decline in urine output in all patients through day 28.


RESULTS
Mean age of participants was 60±15 years old, 72% were men, and 30% were diabetic. In unadjusted models, among patients who survived ≥7 days, mean urine output was, on average, 31.7 ml/d higher (95% confidence interval, 8.2 to 55.2 ml/d) for the less intensive group compared with the more intensive group (P=0.01). More intensive RRT was associated with 29% greater unadjusted risk of decline in urine output of ≥50% (hazard ratio, 1.29; 95% confidence interval, 1.10 to 1.51).


CONCLUSIONS
More intensive versus less intensive RRT is associated with a greater reduction in urine output during the first 7 days of therapy and a greater risk of developing a decline in urine output of ≥50% in critically ill patients with severe AKI.
['Mc Causland|Finnian R|FR|', 'Asafu-Adjei|Josephine|J|', 'Betensky|Rebecca A|RA|', 'Palevsky|Paul M|PM|', 'Waikar|Sushrut S|SS|']
D058186:Acute Kidney Injury D000328:Adult D000368:Aged D005260:Female D017583:Hemodiafiltration D006801:Humans D008297:Male D008875:Middle Aged D011446:Prospective Studies D006435:Renal Dialysis D014556:Urine
critical illness hemodialysis Acute kidney injury Humans Randomized trials as topic renal dialysis renal replacement therapy