Difference between revisions of "Heat stroke"

(Treatment)
Line 66: Line 66:
  
 
==Treatment==
 
==Treatment==
===General===
+
General
*IVF
+
*Remove from environment
**Initiate at a rate that ensures adequate (start w/ NS 250cc/hr)
+
*Address airway, breathing and circulation
 +
*IV normal saline
 +
**Bolus if hypotensive
 +
**Titrate to urine output, start at 250mL/hour
 +
**Avoid aggressive IV fluid resuscitation unless severely dehydrated
  
===Cooling===
+
Cooling
 +
*Mainstay of treatment
 
*Goal is to reduce temp to 39C (102.2F) and then stop to avoid overshoot hypothermia
 
*Goal is to reduce temp to 39C (102.2F) and then stop to avoid overshoot hypothermia
 
*Antipyretics (ASA and acetaminophen) and dantrolene have no role  
 
*Antipyretics (ASA and acetaminophen) and dantrolene have no role  
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***Spray cool water (15C (59F)) on most of pt's body surface; turn on fan
 
***Spray cool water (15C (59F)) on most of pt's body surface; turn on fan
 
***Complications
 
***Complications
****Shivering (occurs when skin temp is <30C (86F): tx w/ short-acting benzos
+
****Shivering (occurs when skin temp is <30C (86F): treat with short-acting benzodiazepines
 
****Electrodes not sticking: place on pt's back instead
 
****Electrodes not sticking: place on pt's back instead
 
**Ice-water immersion
 
**Ice-water immersion
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****Inability to perform defibrillation or resuscitative procedures
 
****Inability to perform defibrillation or resuscitative procedures
 
**Invasive
 
**Invasive
***Consider if evaporative cooling / immersion is insufficient
+
***Consider if evaporative cooling or immersion is insufficient
***Examples: cold water gastric lavage, bladder lavage, rectal lavage
+
***Cardiopulmonary bypass
 +
***Cold water gastric, bladder or rectal lavage
  
 
==Complications==
 
==Complications==

Revision as of 02:11, 26 August 2015

Background

  • Universally fatal if left untreated
  • Types
    • Classic (nonexertional)
      • Seen in children and elderly
    • Exertional
      • Seen in otherwise young, healthy individuals

Clinical Features

  • Heat exposure + elevated temperature >40C (>104F) + neurologic abnormalities:
  • Anhidrosis is frequently present; however, its absence does NOT rule out heat stroke

Differential Diagnosis

Environmental

Environmental heat diagnoses

Non-Environmental

Altered mental status and fever

Diagnosis

  • Diagnosis is made by history and physical exam and exclusion of other diseases
  • Blood glucose
  • CBC
  • Chemistry
  • Arterial blood gas or Venous blood gas
    • PaCO2 is often <20 2/2 hyperventilation
  • Lactate
    • Often elevated in exertional heat stroke
  • Coagulation studies
  • Creatine phosphokinase
  • Urinanalysis
  • ECG
  • Chest x-ray
  • CT brain and/orLP as needed

Treatment

General

  • Remove from environment
  • Address airway, breathing and circulation
  • IV normal saline
    • Bolus if hypotensive
    • Titrate to urine output, start at 250mL/hour
    • Avoid aggressive IV fluid resuscitation unless severely dehydrated

Cooling

  • Mainstay of treatment
  • Goal is to reduce temp to 39C (102.2F) and then stop to avoid overshoot hypothermia
  • Antipyretics (ASA and acetaminophen) and dantrolene have no role
  • Cooling blankets work too slowly to be employed as sole treatment
  • Ice packs to neck, axillae, groin are useful as adjunct only
  • Cold IVF is not effective
  • Techniques
    • Evaporative
      • Method of choice
      • Spray cool water (15C (59F)) on most of pt's body surface; turn on fan
      • Complications
        • Shivering (occurs when skin temp is <30C (86F): treat with short-acting benzodiazepines
        • Electrodes not sticking: place on pt's back instead
    • Ice-water immersion
      • Consider especially in young, healthy pts
      • Complications
        • Shivering
        • Inability to perform defibrillation or resuscitative procedures
    • Invasive
      • Consider if evaporative cooling or immersion is insufficient
      • Cardiopulmonary bypass
      • Cold water gastric, bladder or rectal lavage

Complications

  • Hypotension
    • BP will usually respond to small fluid bolus (500cc) and body cooling
      • If ineffective consider pressors (dopamine or dobutamine)
  • Electrolyte abnormalities
    • Variable: hypokalemia and hyper or hyponatremia may be seen
  • Hematologic
    • DIC or abnormal bleeding
  • Renal failure
  • ARDS
  • Seizure

See Also

References