Obstetrics & PediatricsEvidence-Based Golden Standard
Pediatric Maintenance IV Fluids (Holliday–Segar 4-2-1)
Calculates hourly and 24-hour maintenance fluid requirement from weight using the 4-2-1 rule, plus deficit and standard isotonic replacement fluid choice.
Holliday–Segar (4-2-1): first 10 kg → 4 mL/kg/h · next 10 kg → +2 mL/kg/h · each kg above 20 → +1 mL/kg/h
Energy method: 100 mL/kg/day (first 10 kg) + 50 (next 10) + 20 (remaining)
Maintenance fluid: isotonic crystalloid (0.9% saline or balanced) + 5% dextrose + 20–40 mmol/L KCl (once urine output confirmed)
Published Clinical Benchmark Cases
Clinical Parameters & Inputs
Unit: kg
kg
Clinical estimate of fluid deficit, e.g. 5 = 5% dehydration.
Computed OutputMaintenance 44 mL/h
44mL/h
Diagnostic Interpretation
Maintenance fluid for a 12 kg child is 44 mL/h (1056 mL/24 h) by the Holliday–Segar 4-2-1 rule. Use an isotonic crystalloid with 5% dextrose once glucose is confirmed safe; add potassium only after urine output.
Calculation Breakdown
Holliday–Segar (4-2-1)
40 mL/h (first 10 kg) + 2 mL/kg/h × 2 kg = 44 =44 mL/h
24-hour Volume
44 mL/h × 24 =1056 mL
Clinical Decision Pearls
- Use ISOTONIC crystalloid for maintenance in children (0.9% saline or balanced solution) to avoid iatrogenic hyponatremia — avoid hypotonic fluids.
- Add 20–40 mmol/L KCl only after the child has passed urine and the serum potassium is known.
- Reassess weight, urine output, and electrolytes at least daily; sick children (SIADH) retain free water.
Limitations & Confounders
- The 4-2-1 rule covers insensible + urinary losses only — it does NOT account for ongoing losses (NG aspirate, drains, fever).
- Overweight children: use ideal body weight for maintenance to avoid fluid overload.
Evidence & Citations
- Holliday MA, Segar WE. The maintenance need for water in parenteral fluid therapy. Pediatrics. 1957;19(5):823-832.