Correct Wilderness Medicine Definitions and Their Impact on Care
- PDF / 100,349 Bytes
- 2 Pages / 595.276 x 790.866 pts Page_size
- 91 Downloads / 221 Views
LETTER TO THE EDITOR
Correct Wilderness Medicine Definitions and Their Impact on Care Grant S. Lipman
Ó Springer International Publishing Switzerland 2014
To the Editor, The recent review piece on the management of collapsed or seriously ill participants of ultra-endurance events in remote environments [1] contained several inaccurate definitions pertaining to potentially critical environmental medical situations. This letter is written to correct these, provide more accurate wilderness medicine definitions, and discuss their potential impact on patient care. The limited diagnostic equipment available to the medical providers who routinely staff single and multi-stage ultra-endurance events require competent clinical assessment—and precise medical definitions can augment the decision making in the care of the seriously ill ultra-endurance participant. Firstly, exertional heat stroke (EHS) was erroneously described as a temperature threshold of 41 °C, when actually it’s well accepted definition is a core temperature of at least 40 °C (104 °F) (and, as stated in the review, with the presence of neurologic symptoms) [2]. At this core temperature, the expression of heat shock proteins is altered, direct tissue injury and death via apoptosis occurs, and systemic signs of heat-related injury may manifest. There is complete agreement with Dr. Hoffman et al. that a presumptive diagnosis should be made in the absence of a rectal temperature or temperatures that may be reduced by initial field treatment, but a correct definition may assist the first responder in preventing the possibility of a
G. S. Lipman (&) Division of Emergency Medicine, Department of Surgery, Stanford University School of Medicine, 300 Pasteur Drive, Alway Building, M121, Redwood City, CA 94305, USA e-mail: [email protected]
false-negative diagnosis. Furthermore, critical reviews [3] have shown the lack of utility of evaporative cooling by mist, and its ‘effectiveness’ is an order of magnitude less than conductive cooling. Also, this less efficacious evaporative cooling technique has only been described in ‘classic’ heat stroke, so caution should be applied in extrapolation to EHS. Multiple society position statements [2, 4] say that evaporative cooling be considered only if there are no immersive or conductive measures available for rapid cooling, and the review’s indication that evaporative cooling is similarly effective as the above mentioned techniques may be potentially misleading to providers. Second, in accidental hypothermia, altered consciousness is reportedly seen at temperatures lower than 32 °C (90 °F), with impaired shivering at 30 °C (86 °F), [5] not at 33 °C as stated in the review [1]. As dilutional hyponatremic encephalopathy has been reported in cold environments [6] and may be misdiagnosed as severe hypothermia, these temperature thresholds for clinical signs and symptoms are more than a purely academic discussion. Care of a cold individual with altered mental status whose temperature is above 32 °C and/or not shivering should
Data Loading...
