The case below is a composite drawn from real presentations, de-identified for educational purposes. Heatstroke in brachycephalic breeds is a recurring critical care challenge, and this case illustrates several management decisions that are worth examining carefully.
Presentation
A 4-year-old intact male French Bulldog, 12 kg, presented on a Saturday afternoon after being left in a parked car for an estimated 45–60 minutes in 31°C ambient temperature. The owner noted the dog was unresponsive when found.
On presentation:
- Temperature: 42.4°C (108.3°F)
- Heart rate: 188 bpm, weak and thready
- Respiratory rate: 68 breaths/min, labored
- SpO₂: 88% on room air
- Mucous membranes: brick red, tacky
- Mentation: obtunded, non-responsive to stimulation
Blood was drawn for a stat CBC, serum chemistry, and coagulation profile while the dog was positioned in front of a floor fan and alcohol was applied to the footpads.
Cooling: What We Did and Why
This is where the first divergence from common practice occurred. Many clinicians reach for ice water immersion or ice packs in heatstroke. We did not. The rationale: peripheral vasoconstriction from cold application to the skin paradoxically insulates the core and slows cooling. We used evaporative cooling (fan + room-temperature or slightly cool water misting) targeting a temperature endpoint of 39.5°C, at which point active cooling was stopped to prevent overshoot hypothermia.
The cooling phase took approximately 20 minutes. Core temperature reached 39.4°C within 25 minutes of presentation.
Laboratory Findings
Initial labs were sobering:
- ALT: 740 U/L, ALP: 420 U/L
- Creatinine: 3.4 mg/dL (baseline unknown)
- PT: 24 seconds (reference: < 12 seconds)
- PTT: > 120 seconds
- Fibrinogen: 0.6 g/L (markedly decreased)
- Platelet count: 38,000/µL
This constellation—elevated liver enzymes, azotemia, prolonged coagulation times, thrombocytopenia, and hypofibrinogenemia—is consistent with disseminated intravascular coagulation (DIC) superimposed on multiorgan dysfunction. Heatstroke is one of the most potent triggers of DIC in veterinary medicine, reflecting direct thermal injury to endothelium and systemic inflammatory activation.
Management Decisions
Fluid therapy: We initiated isotonic crystalloid (Lactated Ringer's) at 10 mL/kg/hr, avoiding bolus therapy given the coagulopathic state. The goal was euvolemia and urine output ≥ 1 mL/kg/hr rather than aggressive pressure normalization.
Coagulopathy: Fresh frozen plasma (10 mL/kg IV over 4 hours) was administered to address factor depletion. We did not use heparin—evidence for its use in heatstroke-associated DIC is not compelling, and the bleeding risk in a thrombocytopenic patient is significant.
Gut protection: Heatstroke causes significant gastrointestinal mucosal injury. Sucralfate and omeprazole were initiated empirically.
Nutrition: Despite clinical complexity, we initiated nasoesophageal feeding within 18 hours of stabilization, providing 30% of resting energy requirement initially and titrating up over 48 hours.
Outcome and Lessons
The dog was discharged on day 6 with resolving laboratory abnormalities. ALT at discharge was 320 U/L and trending down; creatinine had normalized.
Key takeaways from this case:
- Evaporative cooling is superior to ice water immersion in heatstroke. Set a target temperature and stop active cooling to prevent overshoot.
- DIC is common in severe heatstroke and should be anticipated, not discovered reactively.
- Early enteral nutrition supports intestinal mucosal integrity in this setting.
- The coagulopathic heatstroke patient requires careful, conservative fluid management—not the aggressive resuscitation approach appropriate for eucoagulable distributive shock.