HWN Suggests

Heat-related Illness Deep Dive

When a patient presents to the emergency department by EMS for heat stroke, do not be fooled by the temperature in a partially cooled patient. Heatstroke is a clinical diagnosis and AMS or other CNS derangement in a hyperthermic patient, even if no longer >104°F should still be treated as an acute heatstroke. On arrival, first, repeat a primary survey and ensure the patient's ABCs are intact. If an airway is required, place it. These patients will generally be tachypneic and oxygen hungry. Every degree over euthermia is associated with a 10-13% increase in oxygen demand (28). Once the primary survey is complete and any required resuscitation is addressed, cooling the patient should become…

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 EM@3AM: Heat Stroke

Nonexertional (classic) heat stroke = evaporative and convective cooling. Exertional heat stroke = cold water immersion.

 Hyperthermia & heat stroke

preferred technique for severe heat stroke: immersive ice bath

 Management of Environmental Heat Injury in the ED

In many emergency departments, complete cold water immersion therapy may not be readily available and limited by the placement of cardiac leads, intubation, and IV access, so evaporative and convective cooling methods become first-line for both exertional and non-exertional heat stroke in the emergency department setting should cold water immersion be unavailable. Should shivering become problematic, benzodiazepines are considered first line therapy. In severe or refractory cases the patient may benefit from ECMO.

Articles of Interest

Emergency Management of Heat-Related Illness

Initial treatment of exertional heat stroke is directed at removing the patient from the offending environment and immediate cooling with cold-water immersion, as it has been shown to be the fastest cooling modality. If cold water immersion is not available, cold water dousing and wet ice towel rotation may be used, but these have not been found to be as efficient.

Environmental Hyperthermia

Ice bath immersion is superior to other forms of cooling. Remove from ice bath at 38.3oC to prevent iatrogenic hypothermia.

Evaluation and Management of Heat Stroke

Although the literature is sparse on the ideal cooling method for EXERTIONAL heat stroke, consider cold water immersion — associated with lowest morbidity and mortality 1 (Level C evidence)

Evidence-Based Heatstroke Management in the Emergency Department

Rapid recognition and management of heatstroke is critical for the healthcare system to successfully adapt to the increases in frequency, intensity and duration of heat waves as a result of climate change. The proposed heat alert algorithm is intended to help ED and prehospital teams identify heatstroke patients, implement critical treatments, and allocate resources in a timely fashion.

Exertional Heat Stroke

The goal of treatment is reducing core body temperature to less than 102F (39C) in less than 30 minutes of collapse or presence of other neurophysiologic deficits. The most rapid cooling rates are achieved with cold water immersion, making this the gold standard for treatment.

Management of exertional heat stroke: a practical update for primary care physicians

Exertional heat stroke (EHS) is a risk to athletes, the military, and others undergoing strenuous exertion, especially in temperate climates. It is defined as a core temperature of >40°C with neurological impairment. It is one of the three commonest causes of deaths in athletes, and, untreated, the mortality may be up to 80%. Even when treated, it is associated with significant short- and long-term morbidity. The number of cases of EHS appear to be on the rise; this may be due in part to increasing numbers of athletes participating in endurance events each year.

When Heat Stroke Strikes, Cool First, Transport Later

Heat stroke strikes when a mixture of physical exertion and weather causes body temperatures to soar to 104 degrees Fahrenheit or higher. Casa says that once body temperatures reach these extremes, irreversible cell damage can set in if the temperature isn't brought down fast — within a 30-minute window.

When Treating Athletes for Heat Stroke, 'Cool First, Transport Second'

The principle of "cool first, transport second" differs from the usual practice of calling 911 and getting to the hospital as soon as possible.

Resources

WikEM

Cooling end point should be ~39°C (102.2°F) - no good data for this goal.