Will changing maintenance intravenous fluid from 0.18% to 0.45% saline do more harm than good?

Area of Science:

• Pediatrics
• Nephrology
• Intensive Care Medicine

Background:

• Current recommendations suggest changing maintenance intravenous fluid in children from 0.18% to 0.45% saline.
• This change may lead to an increase in hypernatraemia cases, potentially outweighing benefits of preventing hyponatraemia.
• A simplified approach to fluid management based solely on plasma sodium and dehydration estimates is insufficient.

Purpose of the Study:

• To evaluate the potential risks and benefits of changing maintenance intravenous fluid composition in children.
• To advocate for a more physiologically-based approach to fluid management in pediatric care.
• To determine the optimal maintenance fluid for pediatric patients.

Main Methods:

• Analysis of the physiological impact of different saline concentrations (0.18% vs. 0.45%) on fluid and electrolyte balance in children.
• Emphasis on incorporating urinary volume, sodium, and creatinine measurements.
• Calculation of fractional excretion of water and sodium for informed fluid regimen decisions.

Main Results:

• The shift to 0.45% saline may cause more harm than good by increasing hypernatraemia incidence.
• Simple formulas and plasma sodium levels are inadequate for determining safe fluid regimens.
• 0.18% saline is a more physiological standard, comparable to oral intake, and should remain the primary maintenance fluid.

Conclusions:

• A shift to 0.45% saline in pediatric maintenance fluids is not recommended due to increased hypernatraemia risk.
• Fluid management must be based on comprehensive physiological assessment, including fractional excretion calculations.
• 0.18% saline offers a safer and more physiological maintenance fluid option for children.