Difference between revisions of "Heat stroke"

(Differential Diagnosis)
Line 1: Line 1:
 
==Background==
 
==Background==
#Universally fatal if left untreated
+
*Universally fatal if left untreated
#Types
+
*Types
##Classic (nonexertional)
+
**Classic (nonexertional)
###Seen in children and elderly
+
***Seen in children and elderly
##Exertional
+
**Exertional
###Seen in otherwise young, healthy individuals
+
***Seen in otherwise young, healthy individuals
  
==Diagnosis==
+
==Clinical Features==
#Heat exposure + elevated temperature >40C (>104F) + neurologic abnormalities:
+
*Heat exposure + elevated temperature >40C (>104F) + neurologic abnormalities:
##Inappropriate behavior
+
**Inappropriate behavior
##Confusion
+
**Confusion
##Delirium
+
**Delirium
##Ataxia
+
**Ataxia
##Coma
+
**Coma
##Seizures
+
**Seizures
#Anhidrosis is frequently present; however, its absence does NOT rule out heat stroke
+
*Anhidrosis is frequently present; however, its absence does NOT rule out heat stroke
##Symptoms seen in [[Heat Exhaustion]] may also be present
+
**Symptoms seen in [[Heat Exhaustion]] may also be present
  
 
==Differential Diagnosis==
 
==Differential Diagnosis==
Line 49: Line 49:
 
{{AMS and fever DDX}}
 
{{AMS and fever DDX}}
  
==Work-Up==
+
==Diagnosis==
#Blood sugar
+
*Blood sugar
#CBC
+
*CBC
#Chemistry
+
*Chemistry
#VBG
+
*VBG
##PaCO2 is often <20 2/2 hyperventiltaion
+
**PaCO2 is often <20 2/2 hyperventiltaion
##Exertional heat stroke often results in lactic acidosis
+
**Exertional heat stroke often results in lactic acidosis
#Coags
+
*Coags
#CK
+
*CK
#UA
+
*UA
#ECG
+
*[[ECG]]
#CXR
+
*CXR
#?CT/LP
+
*?CT/[[LP]]
  
 
==Treatment==
 
==Treatment==
 
===General===
 
===General===
#IVF
+
*IVF
##Initiate at a rate that ensures adequate (start w/ NS 250cc/hr)
+
**Initiate at a rate that ensures adequate (start w/ NS 250cc/hr)
  
 
===Cooling===
 
===Cooling===
#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  
#Cooling blankets work too slowly to be employed as sole treatment
+
*Cooling blankets work too slowly to be employed as sole treatment
#Ice packs to neck, axillae, groin are useful as adjunct only
+
*Ice packs to neck, axillae, groin are useful as adjunct only
#Cold IVF is not effective
+
*Cold IVF is not effective
#Techniques
+
*Techniques
##Evaporative
+
**Evaporative
###Method of choice
+
***Method of choice
###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): tx w/ short-acting benzos
####Electrodes not sticking: place on pt's back instead
+
****Electrodes not sticking: place on pt's back instead
##Ice-water immersion
+
**Ice-water immersion
###Consider especially in young, healthy pts
+
***Consider especially in young, healthy pts
###Complications
+
***Complications
####Shivering
+
****Shivering
####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 / immersion is insufficient
###Examples: cold water gastric lavage, bladder lavage, rectal lavage
+
***Examples: cold water gastric lavage, bladder lavage, rectal lavage
  
 
==Complications==
 
==Complications==
#Hypotension
+
*[[Hypotension]]
##BP will usually respond to small fluid bolus (500cc) and body cooling
+
**BP will usually respond to small fluid bolus (500cc) and body cooling
###If ineffective consider pressors (dopamine or dobutamine)
+
***If ineffective consider pressors (dopamine or dobutamine)
#Electrolyte abnormalities
+
*[[Electrolyte abnormalities]]
##Variable: hypokalemia and hyper or hyponatremia may be seen
+
**Variable: hypokalemia and hyper or hyponatremia may be seen
#Hematologic
+
*Hematologic
##DIC or abnormal bleeding
+
**[[DIC]] or abnormal bleeding
#Renal failure
+
*Renal failure
#ARDS
+
*[[ARDS]]
#Seizure
+
*[[Seizure]]
##Tx w/ benzos
+
**Treate with benzos
  
 
==See Also==
 
==See Also==
Line 108: Line 108:
 
*[[Acute Fever (DDX)]]
 
*[[Acute Fever (DDX)]]
  
==Source ==
+
==References==
Tintinali
 
  
 
[[Category:Environ]]
 
[[Category:Environ]]

Revision as of 13:49, 28 June 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:
    • Inappropriate behavior
    • Confusion
    • Delirium
    • Ataxia
    • Coma
    • Seizures
  • 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

  • Blood sugar
  • CBC
  • Chemistry
  • VBG
    • PaCO2 is often <20 2/2 hyperventiltaion
    • Exertional heat stroke often results in lactic acidosis
  • Coags
  • CK
  • UA
  • ECG
  • CXR
  • ?CT/LP

Treatment

General

  • IVF
    • Initiate at a rate that ensures adequate (start w/ NS 250cc/hr)

Cooling

  • 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): tx w/ short-acting benzos
        • 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 / immersion is insufficient
      • Examples: cold water gastric lavage, bladder lavage, 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
    • Treate with benzos

See Also

References