KDIGO Clinical Practice Guideline for Acute Kidney Injury
Fluids: Recommendations and Rationale

Fluids

• 3.1.1: In the absence of hemorrhagic shock, we suggest using isotonic crystalloids rather than colloids (albumin or starches) as initial management for expansion of intravascular volume in patients at risk for AKI or with AKI. (2B)

Rationale

Despite the recognition of volume depletion as an important risk factor for AKI, there are no randomized controlled trials (RCTs) that have directly evaluated the role of fluids vs. placebo in the prevention of AKI, except in the field of contrast-induced acute kidney injury (CI-AKI) (see Chapter 4.4). It is accepted that optimization of the hemodynamic status and correction of any volume deficit will have a salutary effect on kidney function, will help minimize further extension of the kidney injury, and will potentially facilitate recovery from AKI with minimization of any residual functional impairment. AKI is characterized by a continuum of volume responsiveness through unresponsiveness (Figure 8),^78,82 and large multicenter studies have shown that a positive fluid balance is an important factor associated with increased 60-day mortality.^78,83,84

The amount and selection of the type of fluid that should be used in the resuscitation of critically ill patients is still controversial. This guideline focuses on the selection of the fluid (colloid vs. crystalloid fluid in the prevention and early management of AKI). The three main end-points of the studies explored were the effects on mortality, need for RRT, and—if possible—the incidence of AKI. Although many trials have been conducted to compare fluid types for resuscitation, studies without AKI outcomes were not systematically reviewed for this Guideline. Suppl Table 1 summarizes the RCTs examining the effect of starch for the prevention of AKI.