Furosemide Stress test guided early versus late renal Replacement therapy in mechanically ventilated patients with Acute kidney injury

Background: Acute kidney injury (AKI) in the ICU is one of the life-threatening situations that may need renal replacement therapy (RRT). Survival benefit of early initiation of RRT is still not proven. There is still a debate whether early or late RRT significantly affects morbidity and mortality. Methods: This is a randomized controlled trial (RCT) that was conducted on 94 critically ill subjects with stage 2 AKI, according to KDIGO classification, who were on invasive mechanical ventilation. Recruited subjects were selected only if they failed to respond to furosemide stress test after volume status optimization. Subjects were randomly assigned into two groups according to timing of RRT initiation. In the early group, RRT was initiated without the presence of urgent indications for hemodialysis, whereas in the late group, RRT was implemented only in the presence of one or more of urgent indications such as severe metabolic acidosis or hyperkalemia. Primary outcomes of the study were ICU mortality and length of stay. Secondary outcomes included recovery of renal function in addition to duration of mechanical ventilation. Results: There was no statistically significant difference in the primary outcomes, namely ICU mortality and ICU length of stay. About 51.1% of the subjects survived in the early RRT group, whereas 46.8% survived in the late group (p = .680). Although duration of mechanical ventilation was not significantly different (p = .486), recovery of renal function and less dependency on RRT after discharge, were significantly higher in the early RRT group (p = < .001). Conclusion: Even after choosing AKI patients who failed to respond to furosemide stress test, timing of RRT initiation did not affect survival, ICU length of stay or duration of mechanical ventilation. However, early RRT may have positive effect on RRF for survived patients.