Balanced Crystalloid Solutions

Area of Science:

• Critical Care Medicine
• Nephrology
• Emergency Medicine

Background:

• Intravenous fluid therapy is a cornerstone of critical care.
• Saline (0.9% sodium chloride) has been the traditional fluid of choice.
• Balanced crystalloids offer an alternative with a composition closer to extracellular fluid.

Purpose of the Study:

• To review the evidence comparing saline with balanced crystalloids in acutely ill patients.
• To assess the impact of fluid choice on acid-base balance and clinical outcomes.
• To identify knowledge gaps in intravenous fluid therapy research.

Main Methods:

• Review of preclinical research, patient studies, and randomized trials.
• Analysis of observational studies in critically ill adults.
• Examination of recent large randomized trials comparing fluid types.

Main Results:

• Saline may cause hyperchloremic metabolic acidosis, inflammation, hypotension, and acute kidney injury.
• Balanced crystalloids prevent acidosis and may reduce vasopressor use in surgical patients.
• Observational data links balanced crystalloids to lower rates of acute kidney injury and death in critically ill adults.

Conclusions:

• Growing evidence raises concerns about using saline as the primary crystalloid in critically ill adults.
• Balanced crystalloids appear to be associated with improved patient outcomes.
• Further research is needed to fully elucidate optimal fluid therapy strategies in critical illness.