# Parkland Formula Calculator

> Calculates the first 24-hour crystalloid volume for burn resuscitation from body weight and percent total body surface area burned (4 mL × kg × %TBSA), split into the first 8 hours and the next 16 hours with hourly rates.

- Calculator id: `parkland-formula` · Category: Medical & Clinical (`medical`) · Tool name: `calculate_parkland_fluids`
- Canonical page: https://tttkmbb.com/medical/parkland-formula · This document: https://tttkmbb.com/medical/parkland-formula.md · JSON definition: https://tttkmbb.com/medical/parkland-formula.json

## Purpose

Calculates the first 24-hour crystalloid volume for burn resuscitation from body weight and percent total body surface area burned (4 mL × kg × %TBSA), split into the first 8 hours and the next 16 hours with hourly rates.

**Use when:** You need the Parkland (Baxter) starting fluid estimate for an adult with a burn of about 20% TBSA or more.

**Do not use when:** Burns are small (<15–20% TBSA in adults, <10% in children), for electrical or inhalation injury, or for the ongoing rate, which must be titrated to urine output rather than the formula.

## Input

| Parameter | Type | Unit | Required | Description |
| --- | --- | --- | --- | --- |
| `weight_kg` | number | kg | required | Body weight in kilograms. (> 0, max 500) |
| `tbsa_percent` | number | % TBSA | required | Percent of total body surface area with partial- or full-thickness burns (exclude superficial burns). (> 0, max 100) |
| `ml_per_kg_per_percent` | number | mL/kg/%TBSA | optional, default 4 | 4 for the classic Parkland formula; 2–3 for the modified Brooke / ABA consensus range. (min 2, max 4) |

## Output

| Field | Type | Unit | Description |
| --- | --- | --- | --- |
| `total_24h_ml` | number | mL | factor × weight × %TBSA. |
| `total_24h_liters` | number | L | Same volume in litres. |
| `first_8h_ml` | number | mL | Half of the total, given in the first 8 hours from the time of injury. |
| `first_8h_rate_ml_per_h` | number | mL/h | first_8h_ml / 8. |
| `next_16h_ml` | number | mL | Remaining half over the following 16 hours. |
| `next_16h_rate_ml_per_h` | number | mL/h | next_16h_ml / 16. |

## Formula

`total_24h_ml = ml_per_kg_per_percent × weight_kg × tbsa_percent; first_8h_ml = next_16h_ml = total / 2; rates = first_8h_ml / 8 and next_16h_ml / 16`

Baxter and Shires (1968) derived 4 mL/kg/%TBSA of lactated Ringer's; the 8-hour clock starts at the time of burn, and the ABA advises adjusting the rate to a urine output of 0.5 mL/kg/h in adults because formula volumes often over-resuscitate. Results are informational only and not a substitute for clinical judgement or medical advice.

## Data Sources

- Baxter CR, Shires T (1968) Physiological response to crystalloid resuscitation of severe burns, Ann N Y Acad Sci 150:874-894 — https://pubmed.ncbi.nlm.nih.gov/4973463/ (peer_reviewed, retrieved 2026-09-24)
- StatPearls – Burn Fluid Resuscitation (NCBI Bookshelf) — https://www.ncbi.nlm.nih.gov/books/NBK534227/ (reference, retrieved 2026-09-24)

Data freshness: `static`. Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output.

## API

- `GET https://tttkmbb.com/api/v1/calculate/parkland-formula?weight_kg=…&tbsa_percent=…`
- `POST https://tttkmbb.com/api/v1/calculate/parkland-formula` with JSON body `{"inputs": {…}}`
- Response: unified envelope (`success`, `request`, `result.values`, `result.units`, `sources`, `freshness`, `timestamp`, `next_actions`, `links`); see https://tttkmbb.com/docs/response-format.md
- Schema: https://tttkmbb.com/api/v1/calculators/parkland-formula · OpenAPI operationId `calculate_parkland_fluids` in https://tttkmbb.com/openapi.json
- Authentication: none. Rate limit: fair use, see https://tttkmbb.com/docs/rate-limits.md.

## MCP

- Server: `https://tttkmbb.com/mcp` (Streamable HTTP, JSON-RPC 2.0, no auth)
- Tool:  `run_calculator` with `{"calculator_id": "parkland-formula", "inputs": {…}}`

## Example

- 70 kg, 30% TBSA: inputs `{"weight_kg":70,"tbsa_percent":30}` → `{"total_24h_ml":8400,"total_24h_liters":8.4,"first_8h_ml":4200,"first_8h_rate_ml_per_h":525,"next_16h_ml":4200,"next_16h_rate_ml_per_h":262.5}`
- 80 kg, 45% TBSA: inputs `{"weight_kg":80,"tbsa_percent":45,"ml_per_kg_per_percent":4}` → `{"total_24h_ml":14400,"first_8h_rate_ml_per_h":900,"next_16h_rate_ml_per_h":450}`

```
GET https://tttkmbb.com/api/v1/calculate/parkland-formula?weight_kg=70&tbsa_percent=30
```

## Limitations

Burns are small (<15–20% TBSA in adults, <10% in children), for electrical or inhalation injury, or for the ongoing rate, which must be titrated to urine output rather than the formula. Baxter and Shires (1968) derived 4 mL/kg/%TBSA of lactated Ringer's; the 8-hour clock starts at the time of burn, and the ABA advises adjusting the rate to a urine output of 0.5 mL/kg/h in adults because formula volumes often over-resuscitate. Results are informational only and not a substitute for clinical judgement or medical advice. All values are computed from the formula above; no measurement or live data is involved.

## FAQ

**What if fluids start 2 hours after the burn?**

The first-8-hour half is still due 8 hours after the injury, so the remaining volume is given over 6 hours at a proportionally higher rate.

**How is %TBSA estimated?**

Rule of nines or a Lund-Browder chart for children; the patient's palm (including fingers) is about 1% TBSA. Only partial- and full-thickness burns count.

## Related

- [Maintenance Fluids Calculator](https://tttkmbb.com/medical/maintenance-fluids.md) — Children also need maintenance fluids in addition to resuscitation volume.
- [Body Surface Area Calculator](https://tttkmbb.com/health/body-surface-area.md) — Absolute body surface area from height and weight.