Mild Hypothermia

Scenario:

You are working at the Marathon de Sables, an ultramarathon through the Sahara desert. One of the runners has been running through the night and has collapsed on the course.

The casualty doesn’t know where they are, is taking off layers, struggling with any fine motor skills, complaining in general; they may try to wander off and keep going with the race.

D – nil

R – they are responsive to voice but confused and disorientated, taking off their layers etc.

(C) - Nil

A – airway patent, trachea central.

B – equal bilateral chest expansion, equal bilateral air entry, O2 sats are 98%, RR is 12.

C – BP is 121/78, HR is 65bpm. Chest, abdo, pelvis, long bones are clear. No obvious bleeding. Capillary refill > 2 sec peripherally, < 2 sec centrally, pale skin.

D – temperature is 34.5C, BM is 4.8mmol/L, pupils equal and reactive to light.

E – 

SAMPLE History:

S+S – confusion, poor co-ordination, shivering, change of personality.

A – nil

M – taking ibuprofen for muscle pain

P – nil significant

L – has been eating reasonably regularly but has lost their appetite somewhat, regularly rehydrating with electrolytes added to water.

E - started to struggle with running 6 hours ago, was chilly as had forgotten to bring extra layers for the overnight portion of the run. Casualty has become increasingly tired, fallen to the back of the race. Stumbling somewhat on the sand. Complaining for the past couple of hours.

Priorities for management: 

Identify the casualty is hypothermic (temperatures at night in the Sahara desert average -4C) and take steps to warm them up (limit convection, conduction, radiation).

Discuss: 

• methods to keep a casualty warm (reducing heat loss to the ground, hot water in Nalgene bottles, layering with warm clothes, remove wet layers, bothy shelters).

• Signs and symtpoms of mild-moderate hypothermia: umbles (stumbles, mumbles, fumbles, grumbles)

• Approximate temperature (Celsius) and associated signs and symptoms: 37 – normal. 33-35 – umbles, personality change, shivering, falling, confused. 32-33 – shivering stops, incoherent. 31-32 – unconscious, risk of cardiac arrest. 30-31 – pulse and breathing undetectable.

• Management: minimising heat loss with insulation, rewarming, consider evacuation.