Exertional heat stroke in a marathon runner with extensive healed deep burns: a case report

Exertional heat injuries are known to affect marathoners and army recruits under hot and humid environmental conditions [1,2]. This occurs when heat production exceeds the body's ability to dissipate heat. Since peripheral vasodilation and sweating can dramatically increase heat loss, the lack of these physiological responses seriously predisposes those with these conditions to exertional heat injuries. The authors report a unique case of a female marathon participant who suffered exertional heat stroke possibly caused by her inability to sweat over a large surface area of her body and thus accumulating heat rapidly.A 36-year-old female who had been running a marathon was brought to the emergency department (ED). She was brought in by the Civil Defence ambulance after she had collapsed at the 10 km mark. According to bystander accounts, she was unresponsive, trembling and her eyes were rolling up. There was no jerking of the limbs to suggest a generalised seizure according to the paramedics.The patient's sister, who was running ahead of her, said that the patient had been well before the marathon and that both had flown in from Australia for the event. The patient used to run regularly, but shorter distances.On arrival, the patient was noted to be obviously confused and disorientated, and kept trying to get off the bed. Her rectal temperature was 41.6°C initially and dropped to 38.4°C at the emergency department. The heart rate was 120 beats/min, blood pressure was 91/48 mmHg, and the oxygen saturation was 98% on room air. Normal saline was administered through an iv cannula in the left antecubital fossa. The cardiovascular and abdominal examination was unremarkable. She was able to move all four limbs, and her pupils were equal and reactive to light.She was noted to have extensive scarring all over her trunk and upper limbs except the hands and the upper part of her face. Previous case records showed that she had sustained deep second and third degree burns over 49