Exertional heat stroke during a cool weather marathon: a case study.

A well-trained male runner in his late 30s collapsed 10 m before the finish line, nearly completing the 42.1-km marathon course in 3 h, 15 min. He was responsive to pain, agitated, diaphoretic, and unable to walk. The race start temperature was 6 degrees C (43 degrees F) with relative humidity of 99% and the 3-h temperature was 9.5 degrees C (49 degrees F) with a 62% relative humidity. Approximately 27 min after his collapse, his rectal temperature in the emergency department was 40.7 degrees C (105.3 degrees F), and his failing respiratory status required intubation. His initial Glasgow coma score was 6-7 of 15. His renal output was minimal until he was cooled and given a large fluid flush. His initial echocardiogram showed a "stunned" myocardium with an ejection fraction of 35%. He had a viral syndrome the week prior to the race and was paced by a "fresh" runner the last 16 km of the race. He left the hospital in 5 d and has now returned to running without problems, although several months passed before he felt well while exercising. Exertional heat stroke can occur in cool conditions, and rectal temperature should be checked in all collapsed runners who do not progress with rapid recovery of vital signs and cognitive function. Runners should be instructed not to compete when ill and should not use nonparticipant pacers during the runs.