Cold Temperature-related Emergencies

Definition/Etiology:

Cold Emergencies:

• Hypothermia
• Mild: 93-95
• Moderate: 86-93
• Severe: <86F

Frostbite:
Traumatic condition results from the formation of ice crystals in the extracellular spaces. Once the cells are frozen, the damage is irreversible.

Pathophysiology:

Hypothermia: Heat loss through convection, conduction, radiation or evaporation. Heat loss can overwhelm the body’s ability to compensate. Most of the body’s processes are temp related and changes evolve with decreasing temps.

Frostbite: Frostbite tends to occur when the body is exposed to intense cold, resulting in vasoconstriction. The resulting decrease in blood flow fails to deliver heat to the tissues and eventually leads to ice crystal formation. Body parts most prone to frostbite include the feet, hand, ears, lips, and nose.

Clinical Presentation:

Hypothermia:
Different systems will show different symptoms as the temp drops:

CNS: Progressive decline in LOC

• Sluggish pupils
• Unconsciousness may result between 89.6 and 86F

Cardiovascular:

• Initially – tachycardia, HTN, & cardiac output.
• Later – Bradycardia
• A-fib
• Prolonged QT
• Asystole almost universal at 64.4F

Respiratory:

• Depressed cough reflex
• Increased secretions can lead to aspiration

Renal:

• “Cold Diuresis” – peripheral vasoconstriction leads to central hypovolemia

Hematologic:

• Coagulopathies and DIC

Digestive:

• Slowed peristalsis
• Slowed hepatic function
• Insulin ineffective at 86F

Frostbite:

Superficial-

• Local burning, numbness, tingling
• Whitish, waxy skin
• Stinging during rewarming
• Large blisters

Deep Frostbite-

• Slight burning followed by numbness as the area freezes
• Whitish or yellow-white discoloration
• Swelling and intense burning during rewarming
• Blisters
• Edema that may persist for months
• Severe discoloration and gangrene are late findings

Collaborative Management:

Hypothermia:

• Not dead till warm and dead!
• Rewarm!
• Heating blankets
• Bair hugger
• Apply external heat
• Warm IV solution
• Peritoneal lavage
• Severe may require extracorporeal circulation via cardiac bypass, or hemodialysis. Yes, these patients may be so cold that the only way to warm them is to remove their blood, warm it, and put it back.
• Give meds judiciously – basically be careful and remember what you give! Hypothermic patients metabolize drugs poorly and may receive a large bolus once warmed.

Frostbite:

• Protect injured part from further damage
• Do not use friction for rewarming – makes things worse
• Immerse part in temp controlled water t 98.6-104F
• Encourage gentle motion in water, but no rubbing
• Once thawed, protect and immobilize the extremities. Use bulky sterile dressings and avoid pressure
• NSAIDS and more if needed
• Rehydrate and address any other concerns

Evaluation | Patient Monitoring | Education:

Number 1 eval….core temp!
For hypothermia, are they getting warmer? Temp sensing foley is probably a good initial intervention for evaluation.

Frostbite –
Evaluate injured areas. Treat for pain during rewarming. Assess perfusion during rewarming.
Education: Well, what happened, why did the frostbite occur? Were they shoveling snow or are they homeless and don’t have warm clothing?
Remind not to smoke or drink in extreme cold. Keep skin and clothing dry.

Linchpins: (Key Points)

• NDTWD – Not dead till warm and dead
• Fast or slow – rewarming in hypothermia – fast. In frostbite – not so much
• Pain control – this is going to hurt
• Blinders – what are the underlying causes or concurrent conditions