Heat Stroke

Question 1

What is the pathophysiology of heat stroke?

Answer 1

Heat stroke is a medical emergency in which body temperature may exceed 104°F (40°C). It has a high mortality rate if not treated in a timely manner. The victim’s thermoregulation mechanisms fail and cannot adjust for a critical elevation in body temperature. If the condition is not treated or the patient does not respond to treatment, organ dysfunction and death can result.

Exertional heat stroke has a sudden onset and is often the result of strenuous physical activity (especially when wearing too heavy clothing) in hot, humid conditions. Classic heat stroke, also referred to as nonexertional heat stroke, occurs over a period of time as a result of chronic exposure to a hot, humid environment such as living in a home without air conditioning in the high heat of summer.

Question 2

What are some assessment findings that would be seen in a patient with heat stroke?

Answer 2

Victims of heat stroke have a profoundly elevated body temperature (above 104°F [40°C]). Although the patient’s skin is hot and dry, the presence of sweating does not rule out heat stroke—people with heat stroke may continue to perspire.

Mental status changes occur as a result of thermal injury to the brain and are the hallmark findings in heat stroke. Key Features: Heat Stroke demonstrates common signs and symptoms of this condition. Cardiac troponin I (cTnI) is frequently elevated during nonexertional heat-related illnesses; research indicates that this test can be used to cost effectively predict severity and organ damage at the beginning of heat stroke, even in a remote setting.

Question 3

What happens to body temperature?

Answer 3

Body temperature more than 104°F (40°C)

Question 4

What happens to the skin?

Answer 4

Hot and dry skin; may or may not perspire

Question 5

What mental status changes may occur?

Answer 5

• Acute confusion
• Bizarre behavior
• Anxiety
• Loss of coordination
• Hallucinations
• Agitation
• Seizures
• Coma

Question 6

What vital sign changes may occur?

Answer 6

• Hypotension
• Tachycardia
• Tachypnea (increased respiratory rate

Question 7

Which main electrolytes may be imbalanced?

Answer 7

Sodium and potassium

Question 8

What happens to renal function?

Answer 8

Decreased renal function (oliguria)

Question 9

What happens to the patients ability to clot?

Answer 9

Coagulopathy (abnormal clotting)

Question 10

What does the patient exhibit pulmonary wise?

Answer 10

Pulmonary edema (crackles)

Question 11

What is done to the patient at the scene?

Answer 11

• Ensure a patent airway.
• Remove the patient from the hot environment (into air-conditioning or into the shade).
• Contact emergency medical services to transport the patient to the emergency department.
• Remove the patient’s clothing.
• Pour or spray cold water on the patient’s body and scalp.
• Fan the patient (not only the person providing care, but all surrounding people should fan the patient with newspapers or whatever is available).
• If available, place ice in cloth or bags and position the packs on the patient’s scalp, in the groin area, behind the neck, and in the armpits.
• If immediate immersion in cold water is possible, support the patient in the water for rapid cooling and protect the patient’s airway. (Note: this is the best method to treat heat stroke.

Question 12

What is done for the patient at the hospital?

Answer 12

• Give oxygen by mask or nasal cannula; be prepared for endotracheal intubation.
• Start at least one IV with a large-bore needle or cannula.
• Administer fluids as prescribed, using cooled solutions if available.
• Use a cooling blanket.
• Obtain baseline laboratory tests as quickly as possible: urinalysis, serum electrolytes, cardiac enzymes, liver enzymes, and complete blood count (CBC).
• Do not administer aspirin or any other antipyretics.
• Insert a rectal probe to measure core body temperature continuously or use a rectal thermometer and assess temperature every 15 minutes.
• Insert an indwelling urinary drainage catheter.
• Monitor vital signs frequently as clinically indicated.
• Assess arterial blood gases.
• Administer muscle relaxants or benzodiazepines as prescribed if the patient begins to shiver.
• Measure and monitor urine output and specific gravity to determine fluid needs.
• Stop cooling interventions when core body temperature is reduced to 102°F (39°C).

Question 13

What is done as far as first aid and prehospital care?

Answer 13

Do not give food or liquid by mouth because vomiting and aspiration are risks in patients with neurologic impairment. Immediate medical care using advanced life support is essential.

Question 14

What is done at the hospital to care for the patient?

Answer 14

• The first priority for interprofessional collaborative care is to monitor and support the patient’s airway, breathing, and circulatory status.
• If shivering occurs during the cooling process, midazolam or propofol may be prescribed. Be aware that midazolam places the patient at high risk for delirium, and propofol carries a risk of hypotension. Seizure activity can further elevate body temperature and is also treated with an IV benzodiazepine. Once the patient is stabilized, admission to a critical care unit may be warranted to monitor for complications such as multisystem organ dysfunction syndrome and severe electrolyte imbalances, both of which increase mortality risk.