Medicine
Optimal Resuscitation Fluid Selection in Burn Patients
Quick fact
The Parkland formula, the most common burn resuscitation guideline, uses Lactated Ringer's—not normal saline—because it closely mimics blood plasma and helps prevent hyperchloremic acidosis.
Why this is interesting
A burn over 20% of the body can kill through dehydration within hours—but the fluid you give can also kill if it’s the wrong kind. How do doctors choose what to pour into a patient’s veins?
Read the full explanation
Understanding Optimal Resuscitation Fluid Selection in Burn Patients
When a large area of skin is burned, the body’s capillaries become leaky, allowing plasma to escape into the tissues. This creates massive fluid loss and shock. To keep the patient alive, doctors give intravenous fluids—but the choice is critical. The most common fluid is Lactated Ringer’s (a crystalloid), which is a balanced salt solution that resembles the body’s own electrolyte makeup. It spreads quickly into the bloodstream and then into tissues, helping to maintain blood pressure and perfusion. The Parkland formula helps calculate the volume needed in the first 24 hours, but the type of fluid is just as important. Normal saline, though similar, can cause too much chloride and lead to metabolic acidosis, making things worse.
A deeper explanation
The optimal fluid selection depends on the phase of injury. In the first 24 hours, capillaries are intensely leaky, so colloids (like albumin) would leak out too and worsen edema—thus crystalloids like Lactated Ringer’s are preferred. After that, the capillary leak begins to seal, and colloids may be added to reduce the total volume needed and limit edema. The mechanism behind this is the balance between hydrostatic and oncotic pressures in the vascular space. Crystalloids replace lost volume but dilute plasma proteins, lowering oncotic pressure, which can lead to more tissue edema. Colloids, when the capillaries are no longer leaking, can restore oncotic pressure and pull fluid back into the bloodstream. The choice is further refined by monitoring urine output and other endpoints, adjusting the fluid rate to avoid under- or over-resuscitation. Over-resuscitation can cause abdominal compartment syndrome, while under-resuscitation leads to kidney failure. Thus, 'optimal' is not a single fluid but a dynamic strategy that balances volume expansion with minimizing complications.