Hypothermia

Question 1

Define hypothermia

Answer 1

Hypothermia is defined as a core body temperature < 35oC. Cold injuries include frostbite and trench foot.

Question 2

Symptoms of hypothermia

Answer 2

change in personality, paradoxical undressing, rocking, dysarthria, ataxia, or frank confusion

Question 3

Frostbite symptoms

Answer 3

first experience pain in the affected areas, then numbness, and may have mistaken the disappearance of pain for improvement.

Question 4

Trench foot symptoms

Answer 4

Lower extremities with prolonged exposure!! to wet and cold conditions develop tissue damage, often presenting as paresthesias, pain, or numbness

Question 5

Mild Hypothermia

Answer 5

32-35 C, Tachypnea and Tachycardia without hemodynamic instability, shivering, hyperventilation, Dysarthria, ataxia, amnesia, altered judgment, apathy, fine and gross motor impairment: “Mumbles, grumbles, stumbles, fumbles, tumbles, and polyuria (cold diuresis)

Question 6

Moderate Hypothermia

Answer 6

28-32 C, Bradycardia, Bradypnea, stop shivering and hyperventilate, Arrhythmias, decreased cardiac output, Paradoxical undressing,
Decreased responsiveness,
Hyporeflexia,
Dilated and sluggish pupils,
Dysarthria
ataxia

Question 7

Severe Hypothermia

Answer 7

<28 C, Bradycardia, Hypotension, Pulselessness, Bradypnea/apnea, rigid muscles, pulmonary edema, V-fib and severely decreased cardiac output, Coma/unresponsiveness
Areflexia
Fixed pupils
Oliguria

Question 8

Trench foot physical exam

Answer 8

skin may appear red and swollen at first, progressing to blisters and bullae and finally hemorrhage in the skin and deeper tissues.

Question 9

Frost bite physical exam

Answer 9

Tissues appear pale and firm, with poor capillary refill and sensation. Severe frostbite appears purple due to blood sludging.

Question 10

Initial actions in a hypothermic patient

Answer 10

• Minimize jerky movement of the severely hypothermic patient as movement or exercise may precipitate ventricular fibrillation
• Stabilize airway: endotracheal intubation if needed for airway protection in the unresponsive patient
• Stabilize breathing: administer warm humidified O2, endotracheal intubation for respiratory failure
• Stabilize circulation: monitor, ECG, intravenous access, warm IV fluids
• Remove cold wet clothing, dry patient, cover with warm dry coverings or warming blanket (bear hugger). Initiate active rewarming measures.
• Look for signs of accompanying cold injury, trauma, or underlying illness (secondary hypothermia)

Question 11

What is the best method for monitoring core body temp?

Answer 11

The best method for measuring and monitoring core body temperature is a low-reading temperature probe in the esophagus or rectum

Question 12

Key facts about rectal probes

Answer 12

Rectal temperature probes (not thermometers) should be inserted five inches into the rectum; lodging the probe in feces will give a falsely low reading. Rectal temperature also lags behind true core temperature during rewarming.

Question 13

EKG changes in hypothermia

Answer 13

J (Osborne) waves in moderate-severe cases
prolonged intervals (PR, QRS, QT)
arrhythmias (atrial or ventricular)

Question 14

Rewarming, mild

Answer 14

Passive external rewarming.
Blankets (remove cold wet clothes first)
Oral hydration with sugared drinks

Question 15

Rewarming, moderate

Answer 15

Passive and Active external rewarming.

Electric or forced warm air blankets + often add noninvasive internal: warm intravenous fluids, warm humidified oxygen

Question 16

Rewarming, severe

Answer 16

Active internal rewarming
warm intravenous fluids, warm humidified oxygen, warm bladder and gastric, or sometimes thoracic or peritoneal lavage (rarely done anymore) central arteriovenous or venovenous rewarming, cardiopulmonary bypass, dialysis

Question 17

Hypothermic patient with dysrhythmia. Can you use lidocaine?

Answer 17

No. Lidocaine is ineffective in hypothermic patients

Question 18

How long should you continue to resuscitate a patient who is hypothermic?

Answer 18

Resuscitate patients in cardiac arrest while rewarming to a core temperature of 32oC before terminating resuscitation efforts, unless the patient’s chest is frozen or there is ice filling the airway.

Question 19

What is a complication of rewarming?

Answer 19

The patient’s temperature may decrease during rewarming (called afterdrop) as peripheral vessels dilate and increase return of cool blood from extremities to the core. Rewarming shock (hypotension) may occur as rewarming causes vasodilatation. Rewarming can also drop pH, electrolyte imbalances, and coagulopathy

Question 20

Treatment of frost bite

Answer 20

Immediately immerse the affected area in warm water (37-39oC).
Remove constricting clothing and jewelry.
Consult surgical services for exploration and debridement. Amputation is usually delayed until the gangrenous tissue has clearly demarcated, ma take months.
Treatment includes ibuprofen as an anti-inflammatory agent, tetanus toxoid, elevation of the affected area, and narcotic analgesia.
New, administration of tissue plasminogen activator to improve perfusion and decrease the incidence of amputation.
Observe for compartment syndrome.
Hypothermia should be treated first before frostbite.

Question 21

Treatment of trench foot

Answer 21

Keep feet warm, clean, and dry. Elevate the extremity.