Environmental: hypothermia

Question 1

Shivering

Answer 1

Increases metabolic requirements of O2 (MRO2) up to 600%
Limited by available glycogen stores
Ceases at 32 degrees C

Question 2

Metabolic response to hypothermia

Answer 2

Initial increase to produce heat

- decreases by half q drop in core temp of 10 degrees C

Question 3

BGL response to hypothermia

Answer 3

• Will decrease with mild chronic hypothermia

- sever hypothermia inhibits insulin thus BGls spike

Question 4

Respiratory reactions to hypothermia

Answer 4

• Respiratory minute volume decreases

- rate becomes inadequate to blow off CO2 = respiratory acidosis

Question 5

Cardiovascular considerations with hypothermia

Answer 5

CO decreases, increased SVR, capillary leakage

-pt becomes hypovolemic

Question 6

Hypothermia metabolic considerations

Answer 6

O2 demand is very high due to shivering,
-increases SVR, decrease CO/RR/Ve decrease O2 to muscles
=anaerobic metabolism / acidosis

Question 7

Enzymatic and medication considerations with hypothermia

Answer 7

Enzymatic function decreases = decrease clotting factors

• enzymes no longer process drugs in liver
• medication bio transformation decreases

Question 8

Hypothermia mild stage

Answer 8

> 32-34 degrees C

-increased BMR, CO, HR begins to fall at 32 degrees

Question 9

Hypothermia moderate stage

Answer 9

29-32 degrees Celsius

• no more attempts to preserve or produce heat
• LOC and SVR fall, acidosis, hyperglycemia, CO falls

Question 10

Hypothermia severe stage

Answer 10

28 degrees C or less. 
Poikilothermic stage. 
-hypotension, ECG changes
-PT, aPTT increase by 50%
-platelets decrease by 40%

Question 11

Hypothermia EKG changes

Answer 11

Prolonged PR, QRS and QT intervals.
VF risk highest at 22 degrees C
Osborne waves evident at 25 degrees C

Question 12

Poikilothermic

Answer 12

Animal kingdom: Animals who assume environmental temps.

Question 13

Hypothermia intubation consideration

Answer 13

Can induce VF

Question 14

When to start CPR

Answer 14

VF or asystole only

Not with PEA

Question 15

Hypothermia medication considerations

Answer 15

Do not administer if less than 30 degrees C

Enzymatic retardation at 33 degrees C

Question 16

Rewarming: Afterdrop

Answer 16

Warming increases CO

• cold stagnant blood from periphery enters core
• acidotic blood, watch for arrhythmias

Question 17

Active internal rewarming

Answer 17

IVF, hemodialysis, gastric lavage, rectal lavage, ECMO

Question 18

Body’s response to cold

Answer 18

Peripheral vasoconstriction, skeletal muscle vasodilation, increased cardiac output and, shivering