Parkland Formula Burn Fluid Calculator
Parkland Formula Burn Fluid Calculator
4 mL per kg per %TBSA of crystalloid over 24 hours, half in the first 8 from the TIME OF THE BURN. The formula is a starting estimate that modern guidance has halved and that is titrated against urine output, not followed.
Parkland formula
Weight × %TBSA × rate70 kg adult, 30% TBSA partial- and full-thickness burn, Parkland rate of 4 mL/kg per per cent
Formula
Half in the first 8 hours from the time of the burn · the remaining half over the next 16 hours
Parkland rate = 4 mL/kg/% · ABA 2023 starting rate = 2 mL/kg/% · modified Brooke = 2 mL/kg/%
- the clock starts at the burn, not at arrival
- this is the commonest practical error with the formula. The first 8-hour period runs from the moment of injury, so a patient who arrives three hours later has five hours left in which to receive the first half. Scotland’s national paediatric burn guideline states the first period as “24 hours from the time of burn injury” and explicitly subtracts the lag from injury to presentation
- rate × weight × %TBSA, and nothing else
- the formula contains no term for depth beyond the inclusion rule, no term for inhalation injury, no term for age and no term for the fluid already given. All of those change the volume a patient actually needs, which is why the computed figure is a starting point
- the halves and the two rates
- half the total over 8 hours and half over 16, so the first-8-hour rate is exactly twice the next-16-hour rate. Equivalently the starting hourly rate is the 24-hour total divided by 16, which is how several protocols write it
- fluid creep, and the move downward
- the ABA’s 2023 guideline calls fluid creep “a phenomenon recognized over two decades ago” and states that excessive resuscitation fluid “leads to increased morbidity and mortality in major burn patients”. One critical-care reference reports that patients receive more fluid than any formula predicts, with about 6 mL/kg/h and up to roughly 250 mL/kg described in published series, and that a permissive-hypovolaemia approach at 3 mL/kg/% reported better organ function. Hence the ABA’s recommendation to start at 2
- titrated against urine output
- the ABA refers to “the standard target of 0.5 mL/kg/hour”, with several of the trials it reviewed using 30 to 50 mL/h. A critical-care reference gives a goal of 0.5 to 1.0 mL/kg/h and cites a 2014 systematic review that found no survival advantage for haemodynamic monitoring over hourly urine output. Paediatric targets are different and higher — see the paediatric burn fluid calculator
- after the first 24 hours
- the formulas diverge. Classical Parkland gives no further crystalloid and uses albumin at 0.3 to 1.0 mL/kg per per cent burn over 16 hours; the modified Brooke uses albumin at 0.3 to 0.5 mL/kg per per cent. Scotland’s paediatric guideline moves to human albumin solution for the second period from the outset. This page covers the first 24 hours only
Worked example
70 kg adult, 30% TBSA partial- and full-thickness burn, Parkland rate of 4 mL/kg per per cent
4 × 70 × 30 = 8,400 mL in the first 24 hours
Half of it, 4,200 mL, in the first 8 hours from the time of the burn — 525 mL/h
The remaining 4,200 mL over the next 16 hours — 263 mL/h, exactly half the first rate
If the patient arrives 3 hours after the burn, 4,200 mL has to be delivered in the 5 hours remaining of that first period: 840 mL/h. Starting the clock on arrival instead would deliver it over 8 hours and leave the patient behind
At the ABA's 2023 starting rate of 2 mL/kg/% the total is 4,200 mL — half as much, and the recommendation exists because the larger volume is associated with harm
Re-estimate the burn at 35 per cent and the Parkland total becomes 9,800 mL. That is 1,400 mL from five percentage points of TBSA, 16.7 per cent more fluid, from one limb segment scored differently
8,400 mL in a 70 kg patient is 120 mL/kg. At 60 per cent TBSA in an 80 kg patient the formula gives 19,200 mL, which is 240 mL/kg — the volume range the over-resuscitation literature is about
Published starting rates for the first 24 hours
| Formula or guideline | Crystalloid rate | Scope |
|---|---|---|
| Parkland, as published 1968 | 4 mL/kg/%TBSA (original range 3.7 to 4.3) | Adults; the reference against which the others are compared |
| Modified Brooke | 2 mL/kg/%TBSA, no colloid in the first 24 h | Adults |
| American Burn Association 2023 | Start at 2 mL/kg/%TBSA “in order to reduce resuscitation fluid volumes” | Adults with burns of 20% TBSA or more; children not addressed |
| Permissive hypovolaemia (one reported approach) | 3 mL/kg/%TBSA, with better reported organ function | Adults; a single series, not a guideline |
| COBIS Scotland, paediatric | 1.5 mL/kg/%TBSA of balanced crystalloid in the first 8 h, then albumin, plus maintenance | Children; a materially different protocol, not a Parkland variant |
Urine output targets as published, with their source
| Target | Population | Source as read |
|---|---|---|
| 0.5 mL/kg/h | Adults | ABA 2023 guideline, “the standard target of 0.5 mL/kg/hour”; its reviewed trials used 30 to 50 mL/h |
| 0.5 to 1.0 mL/kg/h | Adults | Critical-care reference, described as well validated, citing a 2014 systematic review that found no survival advantage for haemodynamic monitoring over hourly urine output |
| 0.5 to 1 mL/kg/h | Young children, under about 30 kg | COBIS Scotland paediatric guideline monitoring section |
| 0.9 to 1.1 mL/kg/h | Children under 30 kg | A paediatric burn centre protocol; 0.4 to 0.6 mL/kg/h at 30 kg and above, and 1 to 2 mL/kg/h with myoglobinuria |
A starting estimate that is widely over-shot
The Parkland formula gives four millilitres of crystalloid per kilogram per percentage point of burn over the first twenty-four hours, half of it in the first eight. Baxter and Shires published it in 1968 with an original range of 3.7 to 4.3 millilitres, and it became the standard because burn shock kills and because the formula is simple enough to start at the roadside. It contains no term for burn depth beyond the inclusion rule, none for inhalation injury, none for age, and none for the fluid already given.
The single most consequential practical detail is that the clock starts at the burn and not at arrival. A patient who reaches hospital three hours after injury has five hours left of the first period in which to receive its half of the volume, so the hourly rate is higher than a naive calculation suggests. Scotland’s national paediatric guideline states this explicitly and subtracts the lag from injury to presentation. Restarting the clock on arrival is a common error and leaves the patient behind from the first hour.
The second thing a reader needs is that the formula is routinely over-shot, and that this is now understood as a harm rather than a margin of safety. The American Burn Association’s 2023 guideline calls fluid creep a phenomenon recognised over two decades ago, and states that excessive resuscitation fluid leads to increased morbidity and mortality in major burn patients and that resuscitation can itself cause harm. Published series describe patients receiving far more than any formula predicts — figures around six millilitres per kilogram per hour and totals of up to a quarter of body weight — with facial swelling, abdominal compartment syndrome and extremity compartment syndrome as the consequences. The guideline’s response is to recommend starting at two millilitres per kilogram per percentage point rather than four, specifically to reduce total volume, with Parkland’s figure as the comparator. The modified Brooke formula has used two for decades, and one reported permissive-hypovolaemia approach used three.
What this means for the number above is that it is where resuscitation starts and not what the patient receives. The quantity actually governing the infusion is the urine output: the ABA refers to a standard target of 0.5 mL/kg/h, a critical-care reference gives 0.5 to 1.0 mL/kg/h and cites a systematic review finding no survival advantage for haemodynamic monitoring over hourly urine output, and paediatric targets are higher again. This page computes what the formula yields and names the published targets. It recommends no volume for any patient, and the decision to start, continue or reduce fluid belongs to the clinician at the bedside.
Frequently asked questions
What is the Parkland formula?
4 mL of crystalloid per kilogram of body weight per percentage point of partial- and full-thickness burn, given over the first 24 hours, with half in the first 8 hours and half over the next 16. Published by Baxter and Shires in 1968 with an original range of 3.7 to 4.3 mL/kg per per cent.
Does the first 8 hours run from the burn or from arrival?
From the burn. This is the commonest practical error with the formula. A patient arriving three hours after injury has five hours left in which to receive the first half of the volume. Scotland’s national paediatric burn guideline states the period as 24 hours from the time of burn injury and subtracts the lag from injury to presentation.
Why do some guidelines now use 2 mL/kg instead of 4?
To reduce total volume. The American Burn Association’s 2023 guideline recommends initiating resuscitation at 2 mL/kg per %TBSA in order to reduce resuscitation fluid volumes, with Parkland’s 4 as the comparator, because excessive resuscitation fluid is associated with increased morbidity and mortality. The modified Brooke formula has used 2 for far longer.
What urine output is the resuscitation titrated to?
The ABA refers to a standard adult target of 0.5 mL/kg/h, and several trials it reviewed used 30 to 50 mL/h. A critical-care reference gives 0.5 to 1.0 mL/kg/h and cites a 2014 systematic review that found no survival advantage for haemodynamic monitoring over hourly urine output. Paediatric targets are roughly double, and two paediatric sources read for this page differ from each other.
Are superficial burns included in the percentage?
No. Only partial- and full-thickness burn is counted; the American Burn Association states that superficial, sunburn-type burns are not counted in TBSA. Including erythema is the classic over-estimate, and because the formula multiplies TBSA by weight and by the rate, a few unnecessary percentage points become litres — 5 points is 1,400 mL at 70 kg on the Parkland rate.
Related calculators
References
- Cartotto R, Johnson LS, Savetamal A, Greenhalgh D, Kubasiak JC, Pham TN, Rizzo JA, Sen S, Main E. American Burn Association Clinical Practice Guidelines on Burn Shock Resuscitation. J Burn Care Res. 2023. doi:10.1093/jbcr/irad125
- Resuscitation of patients with burns: guidelines from the American Burn Association. Am Fam Physician, August 2025 — practice-guideline summary of the 2023 ABA recommendations.
- Deranged Physiology. Fluid resuscitation for the burns patient, Required Reading chapter on environmental injuries — the Parkland, modified Brooke and permissive-hypovolaemia volumes with their sources.
- American Burn Association. Burn Center Referral Criteria — including that superficial burns are not counted in TBSA. ameriburn.org/burnreferral
- Care of Burns in Scotland, NHS National Services Scotland. Paediatric Fluid Resuscitation, NSD610-006.06 version 2.0, 2024.
Not medical advice. For healthcare professionals and education. Reference intervals vary by laboratory and assay — always use your own laboratory's. Never base a dose or a treatment decision on this page alone. Full disclaimer at calcengines.com/disclaimer/