In less severe burns, intravenous therapy may not be required, as oral therapy can suffice to meet the fluid replacement needs. Oral replacement therapy can be used in:
(1) adults with < 15% BSA involved by severe burns
(2) children with < 10% BSA involved by severe burns.
In patients with more extensive burns, intravenous fluid administration is required. Sites of venous access are (in order of preference):
(1) peripheral vein in a nonburned area
(2) central vein in a nonburned area
(3) peripheral vein in a burned area
(4) central vein in a burned area.
Losses of fluid due to evaporative losses can be estimated as:
losses by evaporation in mL/hour =
= (25 + (percent BSA burned)) * (BSA in square meters)
Losses by evaporation are affected by the extent of uncovered wounds, air flows in the room and respiratory ventilation.
The Parkland formula for fluid therapy:
(1) uses Ringer's lactate
(2) is 4 mL per kg per percent BSA burned for the 1st 24 hours
(3) with half in the first 8 hours and the remaining half over the next 16 hours, in addition to maintenance rates.
(4) At the end of the first 24 hours, fresh frozen plasma (FFP) is given at a dosage of 0.5 mL per kg body weight per percentage BSA severely burned.
The Mount Vernon formula
(1) uses 4.5% human albumin
(2) with 3 mL per kg body weight per percentage BSA severely burned.
(3) One sixth of this is infused over each of the following periods: 0-4 hours, 4-8 hours, 8-12 hrs, 12-18 hrs, 18-24 hrs and 24-36 hrs.
Unlimited water drinking should be avoided due to the possible risk for dilutional hyponatremia.
After the initial fluid management, fluid therapy should be adjusted to maintain urine output at about 30-50 mL per hour in the adult (0.5 mL per kg per hour). Because of the risk of sepsis, intravenous access sites should be monitored for evidence of inflammation or infection.
