Heat tolerance in patients with extensive healed burns

Area of Science:

• Thermoregulation research
• Burn injury physiology
• Human heat tolerance

Background:

• Burn injuries can significantly affect the body's ability to regulate temperature.
• Understanding thermoregulatory responses in burn survivors is crucial for their long-term health and rehabilitation.

Purpose of the Study:

• To investigate thermoregulatory differences between burn survivors with varying burn percentages and healthy controls.
• To assess the impact of burn size on physiological responses during heat exposure and exercise.

Main Methods:

• Ten subjects with healed burns (divided into >40% and <30% groups) and healthy controls underwent heat stress testing in a climatic chamber.
• Participants performed bench stepping exercise under controlled temperature (40°C) and humidity (50%).
• Measured parameters included rectal temperature, skin temperature, heat storage, heart rate, and sweat rate.

Main Results:

• Subjects with >40% burns showed significantly higher rectal temperature, skin temperature, heat storage, and heart rate compared to smaller burn groups and controls.
• A strong positive correlation (r=0.89) was found between sweat rate and the percentage of burned area.
• A significant reduction in perspiration area was observed in individuals with larger burn areas, leading to premature study termination for some.

Conclusions:

• Burn survivors with extensive healed burns (>40%) demonstrate impaired thermoregulation and are classified as heat intolerant.
• Reduced sweating capacity due to decreased functional skin surface area is a primary factor in heat intolerance post-burn.
• These findings highlight the need for specific heat management strategies for individuals with significant burn histories.