Cold-Related Injuries #9 Hypothermia – The Alligators

Alligators:
Like alligators, these are some of the problems that seem to sneak up and bite you when you least expect them.

1.  Not recognizing cold, stiff, cyanotic patient as resuscitatable.
The unconscious hypothermia victim, <86°F, has stopped shivering and is in a state of suspended animation (not hibernation). 
They appear breathless – a slow, shallow breath every 10 – 15 seconds.
They appear pulseless; at <90°F the blood is 190% thicker than usual, therefore, the pulse is not palpable, and the heart valves are not slamming shut, so no heart sounds.
The skin is very cool, pale gray or cyanotic, and firm to the touch.
If alive, they are curled up in the fetal position. 
When they die, they tend to extend their limbs and may have vomitus in or around their mouth.
If alive, when you gently pull on an arm, it will extend out; when released, it will flex back against the body.  It takes life to contract a muscle.

2.  Field use of CPR on a functional heart.
If possible, attach to a cardiac monitor. If flatline, they are in arrest.
If they have a cardiac rhythm, they are not in PEA – you just can’t feel the weak pulse.

3.  Criteria for pronouncing dead:
No palpable pulse and ECG is flat line.
No respirations.
Skin color is pale gray, cyanotic, and cold.
They have rigidity.
Pupils are fixed.
Failure to revive after rewarming –  “Not dead until warm and dead.”

4.  Continuing active rewarming past 32°C with a high K and a low pH.
Remember, hypothermia is not a disease.  Take your time.
These folks have normal physiology for that temperature.  With rewarming, the cells hve to have time to adjust the chemistry and move the K back into the cells.

5.  Using too many drugs when cold; anti-arrhythmics, calcium channel blockers.
We do not know how drugs affect the body at subnormal core temperatures, this has never been studied.  Hypothermics have poor peripheral circulation.  Drugs end up pooling in the peripheral circulation. With rewarming, the peripheral circulation is re-established. The drugs will flood into the system with potentially disasterous consequences, i.e. post rewarming overdose.

6.  Confusing immersion with submersion.
Immersion
– When immersed, the airway does not go below the surface of the water.
This is shell hypothermia not drowning, and patients are easily resuscitated.
Submersion – their airway went below the surface; they have drowned, have core hypothermia, and are harder to resuscitate.

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