Key points: -Remember the 4-2-1 rule for calculating maintenance fluids in children -Use of hypotonic fluids is based on historical data in healthy children -Data now supports use of isotonic fluids like NS or LR to reduce risk of hyponatremia and SIADH -Newer data may support LR over NS

Supplemental information AAP 2018 Maintenance Fluid Guidelines: https://publications.aap.org/pediatrics/article/142/6/e20183083/37529/Clinical-Practice-Guideline-Maintenance