A to E: Disability - Disorders of body temperature

Question 1

Define hypothermia

Classify its severity

Answer 1

Body core temperature <35^oC

Swiss staging system:

1. Mild: conscious; shivering; 35-32^oC
2. Moderate: impaired GCS; no shivering; 32-28^oC
3. Severe: unconscious; vitals present; 28-24^oC
4. Cardiac arrest/low flow: no/minimal vitals; <24^oC
5. Death due to <13.7^oC

Question 2

List three risk factors for hypothermia

Answer 2

• Infants or elderly
• Alcohol; drug use
• Exhaustion
• Concurrent illness; injury; or neglect
• Reduced GCS

Question 3

Outline the initial management of hypothermia

Answer 3

• A to E assessment; modified CPR as required
  
  • Check for signs of life up to 1min
• Dry and insulate
  
  • Removal from cold environment; remove wet clothes
  • Mobilise if conscious; otherwise minimal movement
• Rewarming
  
  • Blankets; aluminium foil; warm environment
  • Chemical heat packs
• Rapid transfer to hospital: consider ECLS centres (Swiss II-IV)
  
  • Active rewarming: warm air; warm IVI; ECLS

Question 4

Outline the spectrum of hyperthermia-related disorders

Answer 4

• Heat stress
• Heat exhaustion
• Heat stroke
• Multi-organ dysfunction; cardiac arrest

Question 5

What is heat stroke?

Answer 5

A systemic inflammatory response with:

• Core temperature >40.6^oC
• Altered mental state
• Varying levels of organ dysfunction

Question 6

Give two risk factors for heat stroke

Answer 6

• Elderly: declining thermoregulatory mechanisms
• Lack of acclimatisation
• Dehydration
• Obesity
• Alcohol
• CVD
• Psoriasis; eczema; sclerogerma; burns; CF
• Hyperthyroidism
• Drugs: ^eg. anticholinergics; cocaine; diamorphine

Question 7

Provide two presenting features of heat stroke

Answer 7

• Core temperature >40.6^oC
• Hot, dry skin
• Extreme fatigue; headache; syncope; facial flushing
• Vomiting; diarrhoea
• Arrhythmias; hypotension
• ARDS
• Seizures; coma
• Liver failure; renal failure; rhabdomyolysis

Question 8

Outline the initial management of heat stroke

Answer 8

• Cooling to target T 39^oC
  
  • Cool drinks; fanning; tepid water; ice packs
  • Immersion in cold water: requires cooperative patient
  • Cold IVI; IV cooling catheters; surface cooling; ECMO
• Haemodynamic monitoring; correct electrolytes
• CPR as needed

Question 9

What is malignant hyperthermia?

Answer 9

A genetic sensitivity of skeletal muscles to anaesthesia, characterised by muscle contracture and life-threatening hypermetabolic crisis.

Question 10

Outline the treatment of malignant hyperthermia

Answer 10

• Immediately stop triggering agents
• Oxygen; correct acidosis and electrolyte abnormalities
• Active cooling
• Dantrolene: muscle relaxant