Study protocol for the Balanced Solution versus Saline in Intensive Care Study (BaSICS): a factorial randomised trial

Area of Science:

• Critical Care Medicine
• Fluid Resuscitation
• Clinical Trials

Background:

• The optimal fluid choice for critically ill patients remains debated, with unclear evidence on balanced crystalloid solutions versus saline.
• The impact of fluid infusion rates on patient outcomes in intensive care is not well-established.

Purpose of the Study:

• To determine if balanced crystalloid solutions reduce 90-day mortality compared to saline in critically ill patients.
• To investigate whether slow fluid infusion rates decrease 90-day mortality compared to rapid infusion in this patient population.

Main Methods:

• The Balanced Solution versus Saline in Intensive Care Study (BaSICS) is a pragmatic, 2x2 factorial, randomized controlled trial.
• 11,000 patients from over 100 Brazilian intensive care units were randomized to receive either Plasma-Lyte 148 or saline, and assigned to rapid (999 mL/h) or slow (333 mL/h) infusion rates.
• Blinding of solutions was maintained for patients, providers, and investigators, though infusion rates were not blinded.

Main Results:

• The primary outcome, 90-day all-cause mortality, was assessed.
• Secondary outcomes included renal failure requiring RRT, acute kidney injury, non-renal organ dysfunction (SOFA score), and mechanical ventilation-free days.

Conclusions:

• The BaSICS trial provides robust evidence regarding the comparative effectiveness of balanced crystalloids versus saline in critically ill patients.
• The study also offers insights into the effect of fluid bolus infusion rates on patient outcomes in the intensive care setting.