UMEM Educational Pearls

Category: Critical Care

Title: Fluids and AKI

Posted: 8/21/2012 by Mike Winters, MD (Updated: 4/12/2024)
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AKI and Fluid Balance

  • Up to 70% of critically ill patients develop acute kidney injury (AKI), with 5-6% of ICU patients requiring renal replacement therapy (RRT). 
  • Maintaining adequate renal perfusion is central to the management of AKI in the critically ill patient.  As such, fluids are frequently administered.
  • As we've highlighted in previous pearls, there is mounting evidence to indicate that a positive fluid balance may be detrimental for select critically ill patients.
  • Results from a recent publication suggest a positive fluid balance in patients with AKI may be harmful.
    • Bellomo, et al analyzed data from the RENAL trial to determine the association between daily fluid balance and outcomes.
    • Investigators found a 70% reduction in 90-day mortality for critically ill patients who had a negative mean daily fluid balance compared to those that had a positive balance.
    • A negative fluid balance was also associated with decreased ICU length of stay and the need for RRT.
  • Take Home Point: Once critically ill patients with AKI are resuscitated, maintaining a slightly negative daily fluid balance may be beneficial.


Bellomo R, et al. An observational study fluid balance and patient outcomes in the Randomized Evaluation of Normal vs. Augmented Level of Replacement Therapy trial. Crit Care Med 2012; 40:1753-60.