2009, Intensity of Continuous Renal-Replacement Therapy in Critically Ill Patients (RENAL), NEJM
The RENAL trial was one of the largest trials that addressed an important question of doing continuous renal replacement therapy (CRRT) in critically ill patients with renal impairment. Based on this trial, high intensity CRRT at flow rate of 40 ml/kg/hr was found to have no benefits when compared to conventional CRRT at 25 ml/kg/hr.
Prior to this trial, the ATN trial was done in 2008 and compared high intensity renal replacement therapy with conventional approach in similar critically ill population. Both trials showed no benefits in the high intensity approach. In ATN trial, the stable patients were randomized to intermittent hemodialysis (HD) and the CRRT was reserved for unstable patients only. In contrast, RENAL trial addressed the intensity of CRRT and didn’t involve HD.