MWDs displaying any clinical signs of heat injury require emergency cooling measures. The rate of cooling should be as rapid as possible until the body temperature is 103-103.5°F (39.4-39.7°C). The most rapid, practical, and effective method to reduce body temperature is to soak the patient thoroughly to the skin under running tepid water (60-86°F or 15.6-30°C) or submerge partially in a tub of tepid water. 16-18 The key is to soak the entire MWD as rapidly as possible, and to soak through the hair coat to soak the skin thoroughly. Direct fans on the MWD to facilitate evaporative and surface cooling. If possible, move MWD to a cool room or reduce the ambient temperature of the treatment room.
The value of intravenous fluids in patient cooling and support cannot be overstated. Unless there are specific contraindications, intravenous fluid therapy using room-temperature fluids should be initiated for any MWD with heat stroke. Adequate circulating blood and plasma volume are required for conduction to maximize heat dissipation, and IV room-temperature fluids reduce core body temperature.
Intubate MWDs if apneic or not breathing adequately; maintain intermittent positive pressure ventilation (IPPV) at 8-12 breaths/minute. When intubated, make sure the cuff is properly inflated to protect the airway. Provide supplemental oxygen until pulse oximetry of >95% is confirmed with the MWD breathing room air. Use “blow by” technique to deliver oxygen if not intubated (see K9 Emergency Airway Management CPG), as oxygen masks can increase humidity and prevent heat dissipation.
Placing isopropyl alcohol on the footpads is commonly done and may have some effectiveness.17
Once the MWD’s body temperature is 103-103.5°F (39.4-39.7°C), cease all cooling efforts (e.g., remove fans, return room temperature to normal). Then, dry the MWD and provide passive warming support (such as covering with a blanket), if necessary. Monitor rectal temperature continuously and be prepared to actively warm the patient to prevent an excessive drop in body temperature (rebound hypothermia). Providers should anticipate a period of rebound hypothermia and understand that the delay between rectal temperature and true core temperature likely means that the true core temperature may be lower. Active rewarming (such as forced air warming) should be initiated if the rectal temperature falls below 100°F (37.7°C).
Providers should evacuate any MWD heat stroke casualty to veterinary facilities on an URGENT basis if feasible.