A review of heat stroke and its complications in the canine.

SUMMARY A review of heat stroke and its complications is presented. The etiology, physiology, clinical signs, secondary complications, diagnosis, treatment, necropsy results and prevention of heat stroke are discussed. A clinical case is then presented to illustrate the disorder of heat stroke. INTRODUCTION Adult dogs can survive in an environment in which there are wide variations oftemperature because of their ability to regulate their internal temperature. I The internal temperature, however, must be maintained within the range of SoC above normal to 15°C below the normal temperature of blood to avoid cellular injury or death. Thermal homeostasis occurs when there is a balance between "heat load" and heat dissipation. Heat load is defined as the summation of environmental and metabolic heat. 2 Heat stroke occurs when 'heat load markedly exceeds the ability of body compensatory mechanisms to promote heat loss. In man heat stroke is also due to ineffective ther-moregulation. It is caused by the cessation of sweating, which is the main thermoregulatory mechanism. Heat stroke is characterized by hyperthermia (above 105°F), often complicated by alterations in many systems and organs such as acid-base balance, kidney, liver, cerebral edema, and the blood clotting mechanism.