How this instrument works
A serious burn does more than damage skin — it triggers a body-wide capillary leak, letting fluid and protein escape from the bloodstream into surrounding tissue for roughly the first day after injury. Replacing that lost volume fast enough to keep organs perfused, without drowning the patient in fluid, is the whole problem burn resuscitation exists to solve. The Parkland formula, published by Baxter and Shires in 1968, reduces the starting estimate to two numbers: body weight and the percentage of total body surface area burned, counting only second- and third-degree burns since a first-degree burn doesn't leak fluid the same way.
Multiply weight in kilograms by percentage TBSA burned by 4 mL, and the result is the estimated total crystalloid — specifically lactated Ringer's, chosen because its electrolyte mix resembles what burns actually lose more closely than plain saline does — needed over the first 24 hours. That total splits in half: the first portion runs over just 8 hours, the second over the following 16, because capillary leak is steepest right after injury and tapers as the hours pass. Critically, the 8-hour clock starts at the moment of the burn itself, not when the patient reaches a hospital or a clinician starts writing orders — a patient who took 3 hours getting to care only has 5 hours left in that faster first window, not a fresh 8.
This is a starting estimate, not a fixed prescription. Actual delivery is titrated hour by hour against urine output — targeting roughly 0.5 to 1 mL/kg/hour in adults — plus heart rate, blood pressure, and mental status, adjusting the rate up or down as the patient responds rather than running the calculated total on autopilot. The formula also covers only fluid lost through the burn itself; ordinary maintenance fluid needs are calculated separately and added on top. Giving too much by either the formula or its downstream titration carries its own well-documented risk, sometimes called fluid creep, including abdominal or limb compartment syndrome — resuscitation aims for the target urine output, not simply the largest volume that seems safe.
- Enter Weight in kilograms.
- Enter Burned body surface area as a percentage — second- and third-degree burns only.
- Read Total fluid, first 24h, then First 8 hours and Next 16 hours, and remember the clock on the first window starts at the time of injury.
Worked example — 70 kg, 30% TBSA burned
A 70 kg patient with 30% TBSA burned: 4 × 70 × 30 = 8,400 mL estimated over the first 24 hours. Half of that, 4,200 mL, has to run in the first 8 hours — counted from the moment of the burn, not from arrival at the emergency department. The remaining 4,200 mL follows over the next 16 hours, at roughly a third of the earlier rate.
Scale it up: an 80 kg patient with 40% TBSA burned needs 4 × 80 × 40 = 12,800 mL total, with 6,400 mL of it due in that same fast first-8-hour window — nearly 800 mL every hour before the pace eases for the rest of the day.
Questions
Why does the first 8-hour window start at the time of the burn, not on arrival at the hospital?
Because the capillary leak driving fluid loss starts at the moment of injury, not when treatment begins, so the formula's clock follows the physiology rather than the paperwork. A patient who spent 3 hours reaching a burn center only has 5 hours left in that faster first-half window — the remaining fluid still has to go in on the original 8-hour schedule, not a fresh one starting at arrival.
Does this formula include a patient's normal daily fluid needs too?
No — it covers only the extra crystalloid lost through the burn injury itself. Ordinary maintenance fluid, the baseline amount anyone needs regardless of burns, is calculated separately using standard weight-based methods and added on top of the Parkland total, not folded into it.
Is the Parkland formula the exact amount of fluid a patient will receive?
No — it's a starting estimate for the first 24 hours, not a fixed prescription. Clinicians adjust the actual infusion rate hour by hour against urine output, generally targeting 0.5 to 1 mL/kg/hour in adults, along with heart rate, blood pressure, and mental status, since real fluid needs vary from the formula's prediction in either direction.
What counts toward the %TBSA figure in this calculation?
Only second-degree (partial-thickness) and third-degree (full-thickness) burns count — superficial, first-degree burns like ordinary sunburn are excluded because they don't cause the same capillary leak. TBSA is usually estimated at the bedside with the rule of nines, which assigns each major body region a percentage of total surface area.
Why lactated Ringer's specifically, rather than normal saline?
Lactated Ringer's electrolyte composition is closer to what's actually being lost from burned tissue than normal saline is. Large-volume resuscitation with saline instead has been linked to hyperchloremic metabolic acidosis, so lactated Ringer's became, and remains, the standard crystalloid for this formula.
Can giving too much fluid by this formula cause harm?
Yes — over-resuscitation, sometimes called fluid creep, is a recognized risk in its own right, associated with complications including abdominal and limb compartment syndrome. That's exactly why the formula's total is treated as a starting point to be titrated against urine output and clinical signs, not a volume to be infused regardless of how the patient is actually responding.
References
- Baxter CR, Shires T 1968, Ann N Y Acad Sci — original study (PubMed)
- StatPearls (NCBI Bookshelf) — Parkland Formula
Read this first: This instrument computes a screening figure from population formulas — it is not a diagnosis, and it cannot see the whole picture a clinician can. Use it to inform a conversation, not to replace one.