Burn Fluid Resuscitation Calculator

Formula used

This calculator estimates initial crystalloid volume using a coefficient-based approach:

• Total 24h volume (mL) = Coefficient × Weight(kg) × TBSA(%) × Adjustment
• First 8h target = 50% of total
• Next 16h target = remaining 50%
• Rate for first 8h = First8 target ÷ Hours left in initial 8h

Pediatric maintenance (optional) uses the 4-2-1 rule in mL/hr and is added to the calculated burn resuscitation rates.

How to use this calculator

1. Estimate TBSA (%) using standard burn assessment methods.
2. Enter weight, TBSA, and time since injury in hours.
3. Select a protocol coefficient or set a custom value.
4. Press Calculate to view 24h volume and infusion rates.
5. Titrate fluids to clinical endpoints, especially urine output.
6. Export results to CSV or PDF for documentation and handoffs.

Why early resuscitation matters

Significant burns produce capillary leak and rapid intravascular volume loss. Early crystalloid resuscitation reduces shock risk and supports organ perfusion during the first inflammatory day. The calculated volume is a starting point, not a fixed prescription, and should be rechecked after reassessment.

Core inputs and measurement quality

Weight (kg) and TBSA (%) drive the estimate, so measurement quality matters. A 70 kg patient at 30% TBSA with a 4 mL/kg/% approach estimates 8,400 mL in 24 hours. Revising TBSA to 25% changes the estimate to 7,000 mL, while 20% yields 5,600 mL. Small TBSA errors can materially change hourly rates. Recheck TBSA after debridement, edema changes, or improved exposure.

Protocol coefficients and what they change

Many services start at 4 mL/kg/%TBSA (Parkland) or 2 mL/kg/%TBSA (Modified Brooke). In the 70 kg, 30% TBSA example, 2 mL/kg/% yields 4,200 mL instead of 8,400 mL. That difference is 175 mL/hr across 24 hours, before any catch‑up timing. Coefficients differ, but endpoints decide the final rate.

Time since burn and catch‑up dosing

Half of the 24‑hour volume is targeted within the first 8 hours from burn time. If the patient presents 4 hours after injury, the remaining first‑8‑hour target must be delivered over the next 4 hours, effectively doubling mL/hr compared with immediate presentation. If presentation is after 8 hours, the calculator sets the first‑8‑hour rate to zero and reports the next‑16‑hour rate for ongoing planning.

Endpoints for titration

Titrate to physiology rather than totals. Common urine output goals are about 0.5–1.0 mL/kg/hr in adults and around 1.0 mL/kg/hr in children, alongside improving mentation, perfusion, and lactate/base deficit trends. Many teams also watch heart rate, mean arterial pressure, capillary refill, and serial electrolytes to keep resuscitation balanced. Escalating edema, tense extremities, or rising airway pressures can signal over‑resuscitation. Low urine output with cool peripheries may indicate the opposite and warrants reassessment.

Documentation, exports, and safer handoffs

For continuity, document TBSA method, assumed weight, coefficient, burn time, current infusion rate, and response (urine output and vitals). Include when TBSA was last recalculated and what change triggered it. Clear notes speed consults, transfers, and multidisciplinary decisions today. CSV/PDF exports reduce transcription errors and support clear shift‑to‑shift decisions when the plan evolves.