How to manage a patient with severe heat stroke and altered mental status?

Management of Severe Exertional Heat Stroke with Altered Mental Status

This patient requires immediate ice-water immersion cooling, intravenous volume resuscitation, and ICU admission for monitoring of multi-organ failure.

Immediate Cooling Intervention

Cold-water or ice-water immersion is the mandatory first-line treatment and should be initiated immediately. 1 The Society of Critical Care Medicine's 2025 guidelines provide a strong recommendation that active cooling measures, specifically cold- or ice-water immersion (14-15°C/57.2-59°F), achieve the fastest cooling rate and should be prioritized where available. 1, 2

Cooling Protocol Specifics:

• Target cooling rate: ≥0.155°C/min 2, 3
• Duration: Continue for 15 minutes OR until neurological symptoms resolve, whichever occurs first 2, 3
• Target temperature: Cool to below 39°C/102.2°F 2
• Method: Whole-body (neck-down) immersion in ice water 2, 3

Why Ice-Water Immersion is Critical in This Case:

This is a young, fit military patient with exertional heat stroke—the exact population where ice-water immersion has proven most effective and safe. 1 While evaporative cooling methods are better tolerated in elderly patients with classic heat stroke, they are significantly slower and less effective. 1 The prognosis worsens dramatically when treatment is delayed >2 hours, making rapid cooling the primary determinant of survival. 4, 5

Alternative if Immersion Unavailable:

If a tub is not available, a body bag filled with ice water can be used as an effective alternative. 6 Apply ice packs to neck, axilla, and groin while using evaporative cooling with wet skin and continuous fanning. 2, 3

Concurrent Fluid Resuscitation

Establish IV access immediately and begin aggressive fluid resuscitation while cooling is underway. 2, 3

Fluid Management Strategy:

• Initial approach: Administer crystalloids titrated to restore blood pressure and tissue perfusion 3
• Monitoring target: CVP of 3-8 cm H₂O if central access is obtained 1
• Volume range: Typically 500-2,500 mL titrated to hemodynamic response 1
• Critical consideration: This patient's hypotension (BP 100/60) with tachycardia (HR 120) indicates significant volume depletion from fluid losses during exertion 3

The mortality rate is 33% in hypotensive heat stroke patients compared to 10% in normotensive patients, making aggressive fluid resuscitation essential. 3 Consider invasive hemodynamic monitoring if hypotension persists after initial cooling and fluids. 3

Why Oral Rehydration is Inadequate:

With minimal responsiveness to sternal rub and absent response to verbal stimuli, this patient cannot safely receive oral fluids and requires IV access. 2, 3

ICU Admission and Multi-Organ Monitoring

ICU admission is mandatory for monitoring and managing multi-organ dysfunction. 2, 3

Essential Monitoring Parameters:

• Continuous core temperature monitoring (rectal or esophageal) 2, 3
• Frequent neurological assessments to detect improvement or deterioration 2, 3
• Renal function: Monitor for acute kidney injury and rhabdomyolysis (CK levels) 3, 4
• Hepatic function: Assess for liver injury 3, 4
• Coagulation studies: Screen for disseminated intravascular coagulation 3, 4
• Cardiac monitoring: Evaluate for cardiac dysfunction 3, 4
• Electrolyte panels: Correct disturbances as they develop 2, 4

Airway Management:

Maintain airway patency given her altered mental status; consider intubation if she cannot protect her airway during aggressive cooling. 3 Monitor for recurrent seizures during the cooling process. 3

Critical Pitfalls to Avoid

Do NOT Use Antipyretics or Dantrolene:

Antipyretics (aspirin, acetaminophen) and dantrolene are ineffective in heat stroke and should be avoided. 1, 3 Antipyretics may aggravate coagulopathy and liver injury. 1, 3

Do NOT Delay Cooling for Diagnostic Workup:

Cooling must begin immediately and should not be delayed for laboratory results, imaging, or other diagnostic procedures. 3, 5 The degree and duration of hyperthermia are the major determinants of outcome. 5

Pseudoephedrine Consideration:

The patient's use of pseudoephedrine 120 mg daily is a significant risk factor, as sympathomimetics impair heat dissipation and increase heat production. This medication history supports the diagnosis but does not change immediate management priorities.

Why Other Options Are Inadequate

Evaporative cooling alone (rest in cool environment with loose clothing): Too slow for this critically ill patient with severe CNS dysfunction and hypotension. 1

Supine position with oral rehydration: Patient cannot safely receive oral fluids given her altered mental status; IV access is mandatory. 2, 3

Ice bath with oral electrolytes only: Inadequate monitoring and supportive care for a patient at high risk of multi-organ failure. 3, 4