March 4, 2009
The Parkland Burn Formula
When dealing with a casualty who has suffered partial thickness or full thickness burns, intravenous fluid replacement is a treatment of choice. Too little fluid replacement may prove useless and too much replacement will cause complications such as pulmonary edema. The Parkland Formula was designed as a quick method of establishing proper fluid amounts.
The total body surface area (TBSA) of the burn is first determined by using the palmar method (how many areas the size of the casualty's palm would cover the wound) or by the rule of nines: The adult body is divided into areas consisting of multiples of nine percent...each arm is 9%, each upper or lower leg is 9%, the frontal trunk is 18%, the back 18%, the head is 9%, leaving 1% for burns to the genitalia. In infants the estimate changes as in the figure below.
The casualty's weight is then estimated in Kilograms (1 Kg=2.2 lbs) and multiplied by 4.
To arrive at the total CCs of fluid needed for proper resuscitation we then multiply this number by the percent of body surface burned.
Our casualty has a burn to his legs approximating 18% of body surface: 18
He weighs approximately 100 Kilograms: 100
Therefore 100 x 4 = 400, 400 x 18 = 7200
7200 CCs of fluid are needed.
If we gave this to our casualty in a massive bolus we will not be helping...the lungs will fill with leached fluids, tissues will swell, and lawyers will call... so we divide the fluid amount in half (3600) and give the first half over the first eight hours with the remaining half being administered over the next sixteen hours. Our fluid will be Lactated Ringers, although if only normal saline is available we will have to use that.
Standard IV drip sets for Prehospital cases are usually called Macrodrip sets...they deliver one Ml of fluid for every ten drops in the drop chamber...a Ml (millilitre) equals one CC. In order to deliver 3600 CCs of fluid in eight hours we would set the drip rate at 75 drops per minute, or 7.5 CCs per minute.
7.5 CCs x 480 minutes (8 hours) = 3600 CCs or 3.6 Litres (1000 CCs per Litre)
For the remaining sixteen hours we would reduce to drip rate to 37.5 drops per minute to avoid fluid overload in the body.
3.75 CCs x 960 = 3600 CCs or 3.6 Litres
If all you had was a Microdrip set you would have to calculate with sixty drops equalling one Ml...so use a Macrodrip set!!
In order to simplify the math, I have prepared a Microsoft Excel calculator HERE for downloading
Back to the Article Index