What underlying cause explains edema at the burned areas in a patient with severe burns?

Edema at the burned areas is primarily attributed to the inability of damaged capillaries to maintain fluids. In patients with severe burns, the integrity of the capillary walls is compromised due to thermal injury, which leads to increased vascular permeability. This allows fluid, proteins, and electrolytes to leak out of the blood vessels into the surrounding tissue, resulting in localized swelling (edema).

In addition to direct injury, the inflammatory response that follows a burn injury further exacerbates this condition, leading to additional fluid accumulation in the interstitial space. Therefore, the damaged capillaries cannot effectively retain fluids within the vascular system, contributing to the development of edema in the affected areas. This understanding is crucial for managing fluid resuscitation and monitoring the patient's condition in the context of burn treatment.