Has the time come to abandon chloride-rich resuscitation fluids?

Over the past several years, there has been an increasing focus on the potential impact of resuscitation fluid composition on outcomes in critically ill patients (1-3). Chloride is the most abundant anion in the extracellular fluid, and plays an essential role in many body functions including acid-base balance, muscular activity, osmosis, and immunomodulation (4). Yet in both animal models and observational clinical studies, the use of hyperchloremic (physiologically “unbalanced”) solutions has been linked to increased risk of acute kidney injury (AKI) and/or mortality. However, these associations have not been consistent across studies, and have not been confirmed in clinical trial settings (5). Currently, in the United States, 0.9% saline (chloride content 154 mEq/L) remains the predominant solution used for resuscitation in critically ill patients.