Pre-Hospital Care Podcast Exertional Heat Injury with Harvey Pynn
In this session we will examine Exertional Heat Injury (EHI) within individuals undertaking endurance races, military exercises, or extreme activity. We will draw contrast and parallels to acute behavioural disturbance, what is happening both at the physiological level and some of the autonomic positive feedback mechanisms within EHI. To do this I have Harvey Pynn with me, Harvey is a Lieutenant colonel within the British Military and an Emergency Medicine and air ambulance consultant with GWAAC. In the episode we examine:
· Definitions, spectrum of disease – EHI as a broad definition and spectrum of states
· How are thinking has changed on heat illness and what is happening on a physiological level
· Incidence of EHI; anecdotal and empirical
· The hierarchy of ‘exercise-state’ heat loss – evaporative, convective, conduction, then radiation.
· Heat acclimatisation: Salt concentration (aldosterone mediated), sweating initiation and rate.
· Risk factors (individual, environmental)- concomitant disease or drugs (dehydration, alcohol, co-morbid disease, medication)
· Subtle and not so subtle prodromal signs and symptoms of heat injury & why urine colour isn’t a great marker (lack of micturition during dehydration).
· Preventative measures and treatment modalities in severe EHI
· Analogues of comparison and symptomatology – ABD, drug induced hyperthermia.
· Differential diagnosis and an anecdotal case from Harvey
Please find some related research produced by Harvey pertaining to measuring dehydration and the sequlae of EHI:
Please also see relevant empirical literature that is congruent with the podcast:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5819979/
Please enjoy this episode with an engaging and informative guest.