Components and mechanisms of thermal hyperpnea

Area of Science:

• Physiology
• Thermoregulation
• Respiratory Control

Background:

• Hyperthermia triggers distinct breathing patterns, including thermal tachypnea (panting) and thermal hyperpnea.
• Thermal tachypnea, characterized by increased breathing frequency and decreased tidal volume, aids heat loss while maintaining blood gases.

Purpose of the Study:

• This review focuses on thermal hyperpnea, a breathing response observed in humans with elevated core temperatures.
• It aims to elucidate the unresolved causes and physiological mechanisms of thermal hyperpnea.

Main Methods:

• The review synthesizes findings from studies investigating the mechanisms of thermal hyperpnea.
• It discusses methodologies used to support or refute proposed mechanisms, examining additive or multiplicative effects of body temperature on the response.

Main Results:

• Thermal hyperpnea involves increased tidal volume and breathing frequency, leading to respiratory alkalosis.
• Evidence suggests modulators interact with body temperature to influence this response.

Conclusions:

• Thermal hyperpnea likely serves a crucial heat-loss function, potentially contributing to selective brain cooling in hyperthermic individuals.
• Understanding these mechanisms is vital for managing febrile and hyperthermic patients.