Thermal biology of the laboratory rat.

Objective The authors provide an update on a multidisciplinary approach to the treatment of severely burned patients. A review of studies and clinical trials from the past to the present include fluid resuscitation, sepsis, immune function, hypermetabolism, early excision, wound healing, scar formation, and inhalation injury. Summary background data Advances in treating initial burn shock, infection control, early wound closure, and modulation of the hypermetabolic response have decreased morbidity and mortality in the last two decades. Specialized burn care centers, using a multidisciplinary approach, not only successfully treat large burns and their complications, but provide the necessary rehabilitation and psychological support required for readjustment back into society. Conclusions Thermal injury results in a number of physiologic alterations that can be minimized by adequate fluid resuscitation to maintain tissue perfusion, early excision of burn wounds, and rapid wound coverage. These measures, in combination with antibiotic coverage and nutritional support in the form of early enteral tube feedings, will decrease the hypermetabolic response and the incidence of sepsis that can lead to hemodynamic instability and organ failure. Ongoing clinical trials using anabolic agents (e.g., recombinant human growth hormone) and pharmacologic agents that modulate inflammatory and endocrine mediators (e.g., ibuprofen and propranolol) show promise in the treatment of severe burn injuries.

Current treatment of severely burned patients.

The euthermia-to-hibernation Q10 of metabolic rate (MR) for some hibernators is reported to be greater than 3.0, which suggests that decrease in tissue temperature alone cannot explain the decrease in MR observed in hibernation. It has been proposed that respiratory acidosis is a possible mechanism for suppressing MR below basal levels during entrance into torpor. Data from 11 ground squirrels (Citellus lateralis) indicate that respiratory acidosis occurs during hibernation but that its role may be limited to suppression of thermoregulatory thermogenesis and not suppression of metabolism below basal levels. Retention of CO₂ and onset of acidosis are reflected in transient decreases in respiratory quotient (RQ) during early entrance (.81–.74–.87). Reversal of the acidosis is indicated by transient increases in RQ immediately prior to arousal (.78–1.10–.78). However, Q10 calculations reveal that differences between sleeping MR at thermoneutrality and deep hibernation MR can be explained by the influence of ...

Suppression of Metabolism during Hibernation in Ground Squirrels (Citellus lateralis)

CNS control of body temperature during hibernation

Publisher Summary The nature and severity of an injury, whether arising by accident, necrotizing agent, radiation, or by elective surgery, condition the character of both the immediate and subsequent biochemical changes that occur locally and generally Subject's nutritive state at the time of injury, particularly in respect to labile protein reserves and glycogen, also affects the scale of these changes along with restitution of the lost blood or plasma The environmental temperature, at the time and during the days immediately following the injury or operation, affects the condition too Physical injury results in damage to and loss of body protein locally at the site of injury, either by physical separation of tissue from the rest of the body or by destruction of it in situ  At this time, there is initially a depression in vitality, the ebb phase, which can be transitory or more manifest and there can also be some degree of primary or neurogenic shock The situation can also deteriorate further by loss of blood or plasma oligemia For defense and to initiate repair of the damaged tissues, the injury is generally followed by an increase in metabolic reactions, the flow phase, involving local and general components, which together constitute the inflammatory response and beginning of repair

Dolan F

Papers

A calorimeter for simultaneous determination of heat production and heat loss in the rat.

Determination of energy balance following thermal burns by using gradient calorimetry.