39 - hypothemia and cold

Question 1

6 groups and increased risk

Answer 1

1. extremes of age
2. altered sensorium
3. acute incapacitating illness
   - infections, DKA,
4. metabaolic abnomalities
5. immersion in cold water
6. deficiency in muscle or fat
7. peripheral or autonomic neuropathy

Question 2

4 types of heat loss

Answer 2

1. radiation - 55%
2. evap - 30%
3. conduction - 15% - worse in water
4. convection - minor

Question 3

2 CNS Sx

Answer 3

1. LOC

2. shivering

Question 4

ECG sign

Answer 4

J waves right after QRS

Question 5

resp sign

Answer 5

initial tach followed by decrease

Question 6

5 CV signs

Answer 6

1. brady
2. afib
3. slow vent response
4. V fib
5. asystole

Question 7

behavior signs

Answer 7

undressing and burrowing

Question 8

mgmt steps

Answer 8

1. ABC
2. intubate if necc
3. check glucose and D50W if needed
4. bloodwork
5. assume dehydration
6. hypotension should get dopa
7. begin rewarming

Question 9

3 methods of rewarming

Answer 9

1. passive external
   - for mild
   - warm blankets
2. active external
   - healthy, acute and hemo unstable
   - may be assoc. with arrythmias due to after drop
   - immersion in warms water
3. active core rewarming
   - Tx of choice for those who have arrested, but no sig. trauma
   - warms IV fluids
   - warm humidified O2
   - warm peritoneal lavage
   - warm saline pleural irrigation

Question 10

3 predisposing factors for frostbite

Answer 10

1. prior cold injury
2. conditions that impede circ.
3. conditions affecting judgement

Question 11

4 forms of peripheral cold injuries

Answer 11

1. chillblains
   - mild from drycold
   - young females with raynauds
   - pruritis, erythemia, mild edema
2. trench foot
   - prolonged exposure to wet cold above freezing
   - bullae can dev. and leads to gangrene
   - pain during weight bearing, cold sens
3. frostnip
   - supeficial - like 1st degree burn
4. frsot bite
   - actual freezing of tissue

Question 12

ominous presentation of frost bite

Answer 12

1. not possible to roll dermis over bony promininces
2. small hemmoargic blebs
3. residual hue
4. lack of edema

Question 13

3 stages of cold injury

Answer 13

1. burning and numbness warms to pallor and edema
2. insensate, warms to blistering, still perfuses
3. insensate, warms to blister, necrosis

Question 14

steps to rewarm peripheral

Answer 14

1. remove non-adherent wet cloths
2. immerse in warm water bath
3. don’t end warming early
4. avoid refreezing at all costs
5. avoid direct heat

Question 15

adjunt therapy

Answer 15

• active gentle movement
• parenteral analgesia
• keep elevated
• admit for all but minor