What is a key sign indicating need for escharotomy in a circumferential limb burn?

• A. Persistent pain with signs of ischemia (paresthesias, pallor, weakness) or absent distal pulses despite adequate perfusion pressures
• B. Pain with redness
• C. Itching with edema but normal pulses
• D. Warm limb with normal pulses

Answer: (A)

In a circumferential limb burn, escharotomy is needed when the tight eschar begins to compress underlying tissues and impair blood flow, causing limb ischemia. The most important sign is persistent severe pain with ischemic signs or a drop in distal perfusion such as paresthesias, pallor, weakness, or even absent distal pulses that cannot be explained by external perfusion pressures. This reflects rising compartment pressures from the leathery burn scar, which can cut off arterial inflow and venous outflow despite apparently adequate arterial pressure.

If you see redness alone, itching with edema, or a warm limb with normal pulses, these patterns suggest inflammation or normal perfusion without the critical compression seen in impending or actual ischemia, so they do not indicate the need for an escharotomy.