Pearls and pitfalls to calculating fluid requirements for patients.
A 65-year-old patient with a history of congestive heart failure is brought to your emergency department after sustaining second and third degree burns to her chest and upper extremities. Once the patient is stabilized, you use MDCalc to determine the patient’s initial fluid requirements using the Parkland Formula. As you write your orders, you pause to consider the utility of the Parkland Formula and contemplate how to best monitor and observe this patient’s cardiopulmonary status.
| Parkland Formula:
Fluid Requirements = TBSA burned (%) x wt (kg) x 4 mL Give 1/2 of total requirements in first eight hours, then give second half over next 16 hours. |
| The Good (Why Use It) |
| ● The Parkland Formula is an effective and validated approach to guide the initial fluid management requirements of the acutely burned patient.
● The original and validation studies demonstrated the optimal volume of fluid resuscitation required to reduce rates of hypovolemic shock.[1,2] ● The Parkland Formula is the most widely utilized thermal injury resuscitation formula in North America and is endorsed by the American Burn Association. |
| The Bad (Limitations) |
| ● Overly aggressive fluid resuscitation, termed “fluid creep,” may occur due to lack of emphasis on clinical of endpoints and the nature of goal-directed resuscitation.[3]
● Many severely burned patients have been found to receive considerably more resuscitation fluid than predicted by the Parkland Formula.[3] ● Despite Parkland’s acceptance, there is currently no universal consensus on the appropriate assessment of fluid resuscitation and its effect on outcomes. |
| The Ugly (Misapplication) |
| ● The overestimation of fluid requirements, such as including first-degree burns in the calculation, can lead to hypervolemia and may precipitate complications such as compartment syndrome.[4]
● Burn patients with concomitant cardiovascular or pulmonary disease or those sustaining multisystem trauma may require more or less fluids than the calculated needs.[5] ● Fluid resuscitation is best guided by utilizing the Parkland Formula in conjunction with cerebral perfusion, mean arterial perfusion pressure and urine output (MAP >60 and urine output 0.5-1 mL/kg/hr for adults).[5] |
| Derivation |
| Study: Baxter CR. Fluid volume and electrolyte changes of the early postburn period. Clin Plast Surg. 1974;1(4):693-703.
Methods: A series of experiments conducted on mongrel dogs (n=12) with severe burns resuscitated using varying fluid volumes to elicit a fluid resuscitation formula.
Results: Canine study data was used to develop a fluid resuscitation formula that maintained adequate cardiac output in a cohort of adult patients (n=11) with severe burns. |
| Validation |
| Study: Carotto RC, et. al. How Well Does The Parkland Formula Estimate Actual Fluid Resuscitation Volumes? Journal of Burn Care and Rehabilitation. 2002. Volume 23, Number 4.
Methods: Single center retrospective cohort study that looked at 31 patients admitted to a burn center with >15% BSA burns.
Results: The Parkland formula accurately estimated the initial fluid requirements in these patients although the vast majority of patients required significantly more total fluids than predicted. |
Using the rule of nines, you calculate that your 65-year-old patient (60 kg) has sustained burns totaling 36% of her body surface area. You calculate that according to the Parkland Formula, [LR 4 (ml) x weight (kg) x % BSA burned = LR (ml) over initial 24 hours] her total fluid requirements are 8,640 ml, half of which are to be administered over the first eight hours. You recognize that it’s important to be smarter than the score and therefore guide your fluid resuscitation by careful observation of cardiorespiratory status that includes maintaining a MAP >60 and urine output 0.5-1 mL/kg/hr.
Abbreviations:
LR: Lactated Ringer’s BSA: Body Surface Area (2nd and 3rd degree burns only), MAP: Mean Arterial Pressure.
| Bottom Line |
| The Parkland Formula can help to guide initial fluid management in acutely burned patients and is best utilized in conjunction with careful observation of cardiopulmonary predictors such as cerebral perfusion, mean arterial pressure, and urine output. |
References:
- Baxter CR. Fluid volume and electrolyte changes of the early postburn period. Clin Plast Surg. 1974;1(4):693-703.
- Carotto RC, et. al. How Well Does The Parkland Formula Estimate Actual Fluid Resuscitation Volumes? Journal of Burn Care and Rehabilitation. 2002. Volume 23, Number 4.
- Blumetti J et. al. The Parkland formula under fire: is the criticism justified? J Burn Care Res 2008 Jan-Feb;29(1):180-6.
- Friedstat J, Endorf FW, Gibran NS. Burns. In: Brunicardi F, Andersen DK, Billiar TR, Dunn DL, Hunter JG, Matthews JB, Pollock RE. eds. Schwartz’s Principles of Surgery, 10e. New York, NY: McGraw-Hill; 2014.
- DeKoning E. Thermal Burns. In: Tintinalli JE, Stapczynski J, Ma O, Yealy DM, Meckler GD, Cline DM. eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e. New York, NY: McGraw-Hill; 2016.