Hypothermia

Question 1

What are the two classifications of hypothermia?

Answer 1

Primary and secondary

Question 2

What is primary hypothermia?

Answer 2

Environmental, occurring after immersion in cold water or prolonged exposure to cold weather conditions

Question 3

What is secondary hypothermia?

Answer 3

Occurs secondary to an insult or illness such as infection, alcohol excess, hypothyroidism or major trauma

Question 4

How is hypothermia classified by core body temperature?

Answer 4

• Mild - 32 to 35°C
• Moderate - 28 to 32°C
• Severe - 20 to 28°C
• Profound - < 20°C

Question 5

List three symptoms of hypothermia.

Answer 5

• Shivering
• Hunger
• Dizziness

Question 6

What are two signs of severe hypothermia?

Answer 6

• Bradycardia with arrhythmias
• Cool peripheries secondary to vasoconstriction

Question 7

True or False: Tachycardia is a common initial sign of hypothermia.

Answer 7

True

Question 8

What bedside test is indicated if drug intoxication is suspected in a hypothermic patient?

Answer 8

Urine toxicology screen

Question 9

What might an arterial blood gas show in hypothermia?

Answer 9

Initial respiratory alkalosis, followed by respiratory acidosis as hypothermia worsens

Question 10

What ECG findings are associated with hypothermia?

Answer 10

• Prolonged PR, QRS and QT intervals
• Osborn (or J) waves
• Bradyarrhythmias
• Ventricular ectopics
• Cardiac arrest

Question 11

What blood tests should be performed in suspected hypothermia?

Answer 11

• FBC and CRP for inflammatory markers
• U&Es for renal complications
• Coagulation screen
• Creatinine kinase
• Amylase
• Bone profile and magnesium
• Blood cultures if sepsis is suspected

Question 12

What imaging studies may be indicated in hypothermia?

Answer 12

• Chest X-ray for aspiration pneumonia and pulmonary oedema
• CT head for elderly patients post-fall

Question 13

What is the initial approach for conservative management of hypothermia?

Answer 13

Take an A to E approach; patients may require escalation to intensive care for intubation and ventilation

Question 14

What are the types of rewarming in hypothermia management?

Answer 14

• Passive rewarming
• Active external rewarming
• Active core rewarming

Question 15

Fill in the blank: In severe hypothermia, _______ monitoring may be required.

Answer 15

[core temperature]

Question 16

What should be monitored during fluid resuscitation in hypothermia patients?

Answer 16

Careful fluid balance monitoring due to the risk of fluid overload

Question 17

What is the mainstay of treatment for cardiac complications in hypothermia?

Answer 17

Rewarming

Question 18

What should be considered for malnourished or critically unwell hypothermia patients?

Answer 18

Thiamine

Question 19

What guidelines should be followed in case of cardiac arrest secondary to severe hypothermia?

Answer 19

Resuscitation Council guidelines

Question 20

What invasive management options exist for severely hypothermic patients not responding to other treatments?

Answer 20

• Cavity lavage using warm fluids
• Extracorporeal blood rewarming

Question 21

List two complications of hypothermia.

Answer 21

• Frostbite
• Cardiac arrest

Question 22

What can severe frostbite lead to?

Answer 22

Amputation of non-viable tissues

Question 23

What complication can occur during rewarming in hypothermia?

Answer 23

Hypotension due to vasodilation

Question 24

True or False: Pulmonary oedema is a potential complication of hypothermia.

Answer 24

True

Question 25

What are the complications of peri operative hypothermia?

Answer 25

Impairs blood clotting, leading to increased bleeding times Prolonged recovery Impaired wound healing

Question 26

Which patients are at risk for hypothermia?

Answer 26

A higher ASA grade (2 or above) Major surgery Low body weight Large amounts of cold IV infusions and blood transfusions

Question 27

What is heat stroke?

Answer 27

Core body temp over 40 degrees and CNS dysfunction like coma, seizures or dizziness

Question 28

Which medications shold not be given to patients with heat stroke?

Answer 28

Dantrolene Antipyretic

Question 29

What are the types of heat stroke?

Answer 29

Exertional hat stroke Classic heat stroke from environmental heat

Question 30

What is the target core temperature for treatment of heat stroke?

Answer 30

39 degrees

Question 31

What is heat exhaustion?

Answer 31

mild/moderate illness defined as a core temperature of 38-40°C

Question 32

What is the management of classic heat stroke?

Answer 32

Evaporative cooling (Wetting and fanning of the skin

Question 33

What is the management of exertional heat stroke?

Answer 33

Cold/Ice water immersion (do not use in patients with reduced consciousness)

Question 34

What clotting disorder may occur with heat stroke?

Answer 34

Coagulopathy and bleeding

Question 35

How should core temperature be measured in heat stroke?

Answer 35

Rectal thermometer

Question 36

What hormonal response occurs from hypothermia!

Answer 36

hypothalamus to stimulate the release of TSH and ACTH.

Question 37

What is severe hypothermia?

Answer 37

Below 32

Question 38

What increases risk of hypothermia,

Answer 38

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

Question 39

How do infants with hypothermia present!

Answer 39

limp, unusually quiet and refuse to feed. Heat loss in newborns is extremely common, hence a hat and clothing/ blankets will be applied soon after birth.

Question 40

When do ECG changes occur with hypothermia.

Answer 40

Temperature approaches 32°C to 33°C

Question 41

How are blood results affected in hypothermia?

Answer 41

Haemoglobin and haematocrit can be elevated (due to haemoconcentration). Platelets and WBCs are low due to sequestration in the spleen

Question 42

What is a risk with rapid re-warming!

Answer 42

Distributive shock from peripheral vasodilation

Question 43

What should be avoided in hypothermia!

Answer 43

Don't put the person into a hot bath. Don't massage their limbs. Don't use heating lamps. Don't give them alcohol to drink.