Interactive Guide: Heat Stroke in Children

What is Heat Stroke?

Heat stroke is the most severe form of heat illness, defined by a triad: 1) Exposure to an external heat load, 2) central nervous system (CNS) dysfunction, and 3) a core body temperature that typically (but not always) exceeds 40.5°C (105°F).

Main Types:

Classic (Not for Effort)

It affects vulnerable populations (infants, the elderly, chronically ill) during heat waves. Basal thermoregulation is compromised. The skin is usually hot and dry.

By Effort

It occurs in healthy and active individuals. The metabolic heat generated by intense exercise exceeds the body's ability to dissipate it. The skin is usually hot and sweaty.

Cascade Pathophysiology:

Thermoregulatory failure starts a devastating chain reaction:

Direct Cell Damage: Heat denatures proteins, destabilizes cell membranes and can induce apoptosis (programmed cell death).
Systemic Inflammatory Response (SIRS): Endothelial damage and translocation of endotoxins from the intestine cause a massive release of proinflammatory cytokines.
Multiorgan Dysfunction: The combination of direct thermal damage and SIRS leads to coagulopathy (CID), rhabdomyolysis, acute renal failure, liver injury, and cerebral edema.

Keys to a Quick Diagnosis

The diagnosis is clinical and is based on suspicion in a patient with neurological alteration and hyperthermia in a context of heat exposure.

Heat Exhaustion vs. Heatstroke

Feature	Heat Exhaustion	Heatstroke
CNS	Dizziness, syncope, headache. No severe changes.	Confusion, delirium, seizures, coma.
Temp. Central	Elevated, but < 40.5°C	Typically > 40.5°C
Management	Rest, cooling, oral/IV rehydration.	MEDICAL EMERGENCY: Rapid cooling + Life support.

Suggestive Laboratory Findings

Request tests to evaluate organic dysfunction:

Hemogram: Hemoconcentration, thrombocytopenia.
Biochemistry: Hyponatremia or hypernatremia, hypokalemia, acute kidney injury (elevated Cr/Urea), elevated transaminases (AST > ALT).
Coagulation: Lengthened times, elevated D-dimer (suggestive of DIC).
Others: Elevated CPK (rhabdomyolysis), metabolic acidosis on blood gas analysis.

The Absolute Priority: Cool

The prognosis depends directly on the cooling speed and efficiency. The goal is to lower the core temperature to < 39°C in the first 30-60 minutes.

DON'T!

Never administer antipyretics (paracetamol, ibuprofen). They do not act on hyperthermia due to thermoregulatory failure and can worsen liver or kidney damage.

Cooling Strategies:

Immersion in cold water (2-15°C): It is the gold standard, especially in exertional heat stroke. Immerse the child, monitoring rectal temperature continuously. Remove when reaching 38.5-39°C to avoid overcooling.
Evaporative cooling: If immersion is not feasible. Undress the patient, spray him with warm water (to avoid vasoconstriction), and use powerful fans to maximize convection and evaporation.
Adjuvant measures: Apply ice packs to areas of large vessels (neck, armpits, groin). Infusion of cold IV fluids.

Systemic Support:

ABCDE: Ensure airway, oxygen therapy, cardiac monitoring and IV access.
Fluids: Resuscitation with cold isotonic crystalloids (0.9% Saline). Guide fluid therapy according to hemodynamic response.
Management of complications: Benzodiazepines for seizures, vasopressor support if hypotension persists after fluid therapy, and aggressive management of rhabdomyolysis and DIC.

Lipman GS, et al. Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Heat Illness: 2019 Update. Wilderness Environ Med. 2019.
Bouchama A, et al. Cooling and hemodynamic management in heatstroke: practical recommendations. Crit Care. 2007.
American Academy of Pediatrics. Climatic Heat Stress and Exercising Children and Adolescents. Pediatrics. 2011.
Gauer R, Meyers BK. Heat-Related Illnesses. Am Fam Physician. 2019.
Leon LR, Helwig BG. Heat stroke: a comprehensive review. Annu Rev Physiol. 2010.