Parkland Formula Calculator

After a large burn, heat-damaged capillaries and a systemic release of histamine, prostaglandins, and other mediators make the microvasculature leak protein-rich plasma into the interstitium, both in burned tissue and in uninjured tissue. That loss is not blood loss; it is functional plasma volume disappearing into edema, and it peaks in the first hours and largely settles by 24 to 48 hours. The Parkland formula estimates the crystalloid needed to keep the intravascular compartment filled during that window: 4 mL x body weight in kg x percent TBSA of lactated Ringer solution over 24 hours, with half in the first 8 hours and half over the next 16. The clock starts at the moment of injury, not at arrival, so a patient presenting 3 hours late must receive the same first-half volume over the remaining 5 hours. Only partial-thickness and full-thickness burn area counts, and resuscitation is normally reserved for burns over 20 percent TBSA in adults and over 10 percent in children. Titration is driven by urine output, targeting about 0.5 mL/kg/hour in adults and 1 mL/kg/hour in children under 30 kg. The dominant modern caveat is fluid creep: audits of burn centers repeatedly find delivered volumes well above the Parkland prediction, and over-resuscitation carries real harm - abdominal and extremity compartment syndrome and pulmonary edema. That concern is why the modified Brooke formula at 2 mL/kg/percent TBSA is used as a lower starting point in many units and why the American Burn Association guidance emphasizes endpoint-guided titration over formula adherence.

Systematic burn fluid therapy dates to the Cocoanut Grove nightclub fire in Boston in 1942, after which Oliver Cope and Francis Moore at Massachusetts General Hospital quantified the plasma volume lost into burn edema and related it to burned surface area. Their work produced the first weight-and-area formula. The Evans formula followed in 1952 and the original Brooke formula, from the US Army Surgical Research Unit at Brooke Army Medical Center, in 1953; both combined crystalloid with colloid in the first 24 hours. Charles R. Baxter and G. Tom Shires at Parkland Memorial Hospital in Dallas revised that approach in the 1960s. Their laboratory and clinical studies indicated that colloid given during the first 24 hours largely leaks out through the still-permeable capillaries, so the practical requirement could be met with crystalloid alone, and they derived the 4 mL/kg/percent figure with the half-in-8-hours split. Baxter described the physiology and the resulting protocol in publications including a 1974 paper in Clinics in Plastic Surgery, and the formula acquired the Parkland name from the hospital. The modified Brooke formula, at half the crystalloid volume, was developed subsequently as concerns about volume excess grew. Both remain in the Advanced Trauma Life Support and Advanced Burn Life Support curricula, and the shift over the last two decades has been away from computing a fixed 24-hour volume toward using the formula only to set an initial infusion rate that is then adjusted hourly.