Adult Hypothermia

Question 1

SD4 Mgx

Answer 1

1) R+R
2) Pos - POC (supine)
3) MICA C1
4) Remove wet clothing and pat dry pt
5) Warming blankets/space sheet
6) Heaters in ambulance/house wherever situated
7) IV Access - 18G R)CF
8) Fluids (warmed) if req.
9) MICA up/downgrade/sitrep
10) Extrication
11) Reassess 5/60
12) Load Sig 1 with notification

Question 2

Hypothermia Classifications

Answer 2

Mild 32 – 35°C
Moderate 28 – 32°C
Severe < 28°C

Question 3

Cardiac Arrhythmias

Answer 3

Associated with temperatures < 33°C.
Gentle handling of the patient is essential to avoid stimulating lethal arrhythmias.
Atrial arrhythmias, bradycardias or A-V blocks will generally resolve on rewarming. Antiarrhythmic
medications or trans-thoracic pacing are usually not required unless decompensation has occurred.
Defibrillation and cardioactive medications may not be effective at temperatures < 30°C. VF may
resolve spontaneously upon rewarming.

Question 4

Target temperature for pt’s in AV care

Answer 4

≥24ºC

Question 5

In cardiac arrest if the patient has a temperature < 30°C, why is the interval between doses of adrenaline or amiodarone is doubled

Answer 5

The onset and duration of medications is prolonged during hypothermia.

Question 6

Hypothermia Patho

Answer 6

Exposure to cold stimulus/environment
↓
Peripheral vasoconstriction, ↑catecholamine release, ↑metabolic rate
↓
Sympathetic nervous system initiates ↑HR, ↑BP, ↑RR
↓
Shivering begins to allow muscles to provide heat
↓
Temp falls below 35º - ECG changes (Osbourne waves present)
↓
Temp falls below 32º - shivering stops, body no longer compensates
↓
Temp falls below 30º - glucose transfer ceases and glycogen stores are exhausted
↓
HR, BP, RR, Vt, Blood pH all ↓
↓
Fluid shifts into interstitial space
↓
Progressive bradycardia and further ECG changes, AF, VF, Asystole
↓
Temp falls below 20º - cardiac and resp arrest

Question 7

Shock CPG - pts with inadequate/extremely poor perfusion

Answer 7

O2 if required

Normal Saline 1000mL - 2000mL (warmed in hypothermic pt)

1000mL for pts who have hx of cardiac failure, chronic renal failure, or are elderly. All other pts to receive 2000mL

Question 8

Definition of shock

Answer 8

Shock is a state of cellular and tissue hypoxia due to either reduced oxygen delivery, increased
oxygen consumption, inadequate oxygen utilization, or a combination of these processes.

The strongest indicator of shock is profound hypotension but this may be transiently offset by a
compensatory tachycardia.

Question 9

Signs and Symptoms of shock include

Answer 9

Altered conscious state
Tachypnoea
Diaphoresis, pallor, cold
Hot, flushed (due to vasodilation)
Increased thirst

Question 10

Mild Moderate and Severe Hypothermia Signs and Symptoms

Answer 10

Mild: shivering, tachycardia, Osbourne’s waves, numbness to extremities, drowsiness, lethargy, pallor and cool to touch
Moderate: shivering stops, body no longer compensates, altered conscious state, slurred speech
Severe: slow shallow breathing, loss of conscious, arrhythmias