Heat stroke: Difference between revisions
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==Background== | ==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 | |||
**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}} | ||
== | ==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== | ==Treatment== | ||
===General=== | ===General=== | ||
*IVF | |||
**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 | |||
*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== | ==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== | ==See Also== | ||
| Line 108: | Line 108: | ||
*[[Acute Fever (DDX)]] | *[[Acute Fever (DDX)]] | ||
== | ==References== | ||
[[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
- Classic (nonexertional)
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
- Symptoms seen in Heat Exhaustion may also be present
Differential Diagnosis
Environmental
Environmental heat diagnoses
Non-Environmental
- Infectious
- Endocrine
- Neurologic
- Hypothalamic bleeding or infarct
- CVA
- Status epilepticus
- Toxicologic
- Anticholinergic toxidrome
- Sympathomimetic overdose
- Salicylate overdose
- Serotonin syndrome
- Malignant hyperthermia
- Neuroleptic Malignant Syndrome
- Withdrawal (ETOH, benzo)
Altered mental status and fever
- Infectious
- Sepsis
- Meningitis
- Encephalitis
- Cerebral malaria
- Brain abscess
- Other
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
- Evaporative
Complications
- Hypotension
- BP will usually respond to small fluid bolus (500cc) and body cooling
- If ineffective consider pressors (dopamine or dobutamine)
- BP will usually respond to small fluid bolus (500cc) and body cooling
- Electrolyte abnormalities
- Variable: hypokalemia and hyper or hyponatremia may be seen
- Hematologic
- DIC or abnormal bleeding
- Renal failure
- ARDS
- Seizure
- Treate with benzos