Heat stroke: Difference between revisions

Revision as of 02:11, 26 August 2015

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

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

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

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

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

Authors:

@@ Line 66: / Line 66: @@
 ==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
 *Antipyretics (ASA and acetaminophen) and dantrolene have no role
@@ Line 81: / Line 86: @@
 ***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
+****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
@@ Line 89: / Line 94: @@
 ****Inability to perform defibrillation or resuscitative procedures
 **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==