Table 1.

Inclusion and exclusion criteria

Group	Criterion	Definition
Inclusion (determined on admission to PICU)
	Age	Birth to < 16 years of age
	Location	Admitted to PICU
	Time frame	New admission to PICU within the last 24 h and has received IVFT for ≤ 4 h in PICU
	Decision—clinician decides that IVFT is required	IVFT—all intravenous fluids (boluses and maintenance fluids but not drug dilutions) administered in PICU
	Biochemistry	Admission sodium > 130 mmol/L (measured on admission or no longer than 48 h before randomization)
Exclusion
	Age	≥ 16 years
	Time frame	Received IVFT for > 4 h in PICU
	Pre-existing conditions	- Admitted for a cardiac condition - Chronic kidney disease
	Disease-specific IVFT protocols	- Traumatic brain injury or at risk of cerebral oedema - Burns - Post-liver transplant - Post-renal transplant - Diabetic ketoacidosis - Oncology patients needing hyperhydration