Parkland Formula · What Is It, When It Is Used, and More

The Parkland formula calculates the amount of fluid that should be administered to critically burned patients over the first 24 hours post-injury. Developed in 1968, this formula has led to better patient outcomes and has become an integral part of burn protocols. The first half of the fluid calculated should be administered within the first eight hours, while the second half should be administered over the next 16 hours. Suppose there has been a significant portion of time between the burn injury and the time of hospital admission. In that case, the first half of the fluid should still be administered within eight hours of the burn injury and may need to be administered at a faster rate.

The Parkland formula is as follows: total crystalloid fluid (i.e., a solution with small molecules that can move into cells) over the first 24 hours = 4 milliliters x % TBSA (total body surface area burned) x body weight (kg). In children, the formula is edited to 3 ml x % TBSA x weight (kg). Often lactated ringers (i.e., a solution containing sodium chloride, sodium lactate, potassium chloride, and calcium chloride) are used. Subsequently, maintenance fluids composed of normal saline with 5% dextrose may also be administered to children to prevent hypoglycemia and electrolyte abnormalities.

The Parkland formula may be used by licensed healthcare clinicians, including emergency department clinicians or providers in burn units, when calculating fluid resuscitation requirements for a recent critical burn injury. This formula is used for burns that encompass more than 20% of the total body surface area or 10% of the body surface in children or the elderly, that are either deep partial thickness (i.e., second-degree burns) or full thickness (i.e., third-degree burns). The Parkland formula is not used for first-degree burns as these burns do not typically cause significant hemodynamic shifts. A deep partial thickness burn destroys the epidermis (i.e., the outer layer of skin) and portions of the deeper dermis (i.e., the middle layer of skin, between the epidermis and subcutaneous tissue). Comparatively, a full thickness burn affects the epidermis and dermis and may also destroy the underlying subcutaneous tissue. The Parkland formula is not used for first-degree burns as these burns do not typically cause significant hemodynamic shifts. The Parkland formula is not used for first-degree burns as these burns do not typically cause substantial hemodynamic shifts.

The Parkland formula calculates the ideal amount of fluid required to rehydrate and prevent further damage to an individual burn patient. Life-threatening burns may activate an inflammatory response system, which can increase the capillary permeability, thereby shifting the fluid dynamics and causing intravascular (i.e., within blood vessels) fluid, plasma proteins, and electrolytes to relocate to the interstitial space (i.e., area in the tissue surrounding cells). This fluid shift leads to insufficient intravascular fluid causing hypoperfusion, decreased cardiac output, and consequently cardiogenic shock and tissue damage. If left untreated, hypoperfusion can lead to end organ ischemia. This process begins immediately after a burn and peaks eight to twelve hours later. Therefore, the first 24 hours after a burn injury are critical for fluid resuscitation.