Hypothermia and Hyperthermia

Question 1

What is mild hypothermia?

Answer 1

32-35 degrees body temperature

Question 2

What is moderate or severe hypothermia?

Answer 2

<32 degrees body temperature

Question 3

What are the causes of hypotheramia in the elderly?

Answer 3

Exposure to cold in the environment
Inadequate insulation in the operating theatre
Cardiopulmonary bypass

Question 4

What are the risk factors for hypothermia?

Answer 4

General anaesthesia
Substance abuse
Hypothyroidism
Impaired mental status
Homelessness
Extremes of age

Question 5

What are the signs of hypothermia?

Answer 5

Shivering
Cold and pale skin
Slurred speech
Tachypnoea
Respiratory depression
Bradycardia
Confusion

Question 6

What are the investigations for hypothermia?

Answer 6

12 lead ECG
Temperature
FBC
Blood glucose
ABG
Coagulation factors
CXR

Question 7

What would be seen on an ECG in hypothermia?

Answer 7

Acute ST elevation
J wave

Question 8

What might be seen on bloods in someone with hypothermia?

Answer 8

Elevated haemoglobin and haematocrit
Hypokalaemia

Question 9

What is the initial management of hypothermia?

Answer 9

Remove patient from environment
Remove wet blankets or clothing
Warm the body with blankets
Secure the airway and monitor breathing
Warm IV fluids or passing warm air over the patient

Question 10

What is the definition of hyperthermia?

Answer 10

Body temperature of more than 40 degrees

Question 11

What features of the elderly make them more susceptible to hyperthermia?

Answer 11

Reduced cardiac output
Chronic volume depletion
Normal deficiencies in heat shock protein

Question 12

What are the features of hyperthermia?

Answer 12

Agitation
Lethargy
Seizures
Hot dry skin
Elevated core body temperature
Intense thirst
Weakness
Syncope
Headache
Tachypnoea
Tachycardia

Question 13

What are the risk factors for hyperthermia?

Answer 13

Age > 65
Pre-existing dehydration
Obesity
Environmental factors
Diabetes
Cardiovascular disease
Congenital disorders
Drug and alcohol misuse
Medications
- Diuretics
- Beta blockers
- Anticholinergics
- Antidepressants
- Antihistamines

Question 14

What investigations should be performed in someone with hyperthermia?

Answer 14

FBC
LFTs
Renal function
Rectal temperature
Glucose
U&E
ABG
Creatinine Kinase
Urinalysis
ECG

Question 15

What electrolyte abnormalities might be seen in hyperthermia?

Answer 15

Hypokalaemia
Hyponatraemia

Question 16

What other blood tests results might be seen in hyperthermia?

Answer 16

Elevated CK
Elevated urea
Elevated ALT and AST

Question 17

What is the management of hyperthermia?

Answer 17

Remove excess clothing
Rapid active cooling:
- Wetting and fanning the skin
- Wetted ice packs
Oxygen
IV fluids
Small dose benodiazepines

Question 18

What temperature should patients with hyperthermia be cooled to?

Answer 18

No less than 39 derees

Question 19

Why are IV benzodiazepines sometimes given in hyperthermia?

Answer 19

IV benzos increase shivering, which causes heat gain and makes cooling less effective
- this ensures that patients are not cooled too much or too quickly