1. Hypothermi
a
- The silent killer in the
Cold
Presented By:
Ganesh Gupta
2. Introduction
• Derived from Greek word: υποθερμία which means Hypo: less
and thermia: temperature
• A condition in which the internal body temperature falls below
37oC (95 F)
• Prolonged exposure to cool or freezing temperatures
• It DOES NOT need to be below freezing temperatures
• Shivering and mental confusion is the most common symptom.
• Water, wind & cold combination is especially dangerous 2
3. History
Martime / War litérature
Hannibal expérience in 218 B.C
Battle of Stalingrad in World War II
Civilian Loss of life due to sinking of
RMS Titanic (1912) and
RMS Lusitania (1917)
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5. Epidemiology
• Defined as temperature <35O C (<95O F)
• 900 die each year in US from hypothermia
• ½ of those are 65+ years old
• Individuals at age extremes and those with Acute
Mountain Sickness (AMS) are at greatest risk
• Not confined to any country or region.
• Most common in Alaska, North America and
Europe, Quebec Province of Canada and Siberia
Region.
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6. Température Classification:
Normal 36.5–37.5 °C (97.7–
99.5 °F)
Hypothermia <35.0 °C (95.0 °F)
Fever >37.5–38.3 °C (99.5–
100.9 °F)
Hyperthermia >37.5–38.3 °C (99.5–
100.9 °F)
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7. Hypothermia Classification:
Hypothermia: <35.0 °C
Based on Severity, it is futher classified:
Mild : 32-35°C
Moderate : 28-32°C
Severe : < 28°C
Injuries that can either be present alone or in combination
with hypothermia include:
Chilblains ,Frostbite ,Frostnip ,Trench foot 7
8. Mild Hypothermia (> 32 °C)
• Increase metabolic rate
• Maximum shivering thermogenesis
• Amnesia / dysarthria / ataxia
• Hyperglycemia / Loss of coordination
• Tachycardic, tachypneic
• Normal BP
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9. Moderate Hypothermia (28– 32 °C)
• Stupor
• Violent shivering
• Low Bradycardic and Blood Pressure
• Pupils gets dilated (< 30°C)
• Body skins turns pale or white
• Lips, ears, fingers and toes may become blue.
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10. Severe Hypothermia (<28 °C )
• Coma
• Difficulty in speaking / sluggish thinking /amnesia
start
• Inability to use hands / Stumbling
• Cellular metabolic processes shut down.
• No corneal or oculocephalic reflexes
• Apnea /Asystole
• Low Pulse rate but fast Heart Rate
• Flat EEG (19°C)
Beyond 28 °C, the brain activity stop and the
person is dead. 95% true in all cases. 10
11. Paradoxical Undressing
• 20 – 50% of hypothermia deaths
• Occurs during moderate to severe hypothermia
• Person becomes disoriented, confused, and combative
• They begin discarding their clothing, which, in turn,
increases the rate of heat loss
Terminal Burrowing
• Hypothermia is also known as Hide – die Syndrome.
• The process is similar to Hibernation
• Indoors: enter small enclosed spaces such as wardrobes,
cupboards and closets
• Outdoors: piles of leaves, crevices between rocks or 11
fallen trees.
13. Who are at the Risk Factors for
Hypothermia?
• Age : Young / Old age is at higher risk.
• Mental status : Impaired Judgment.
• Substance Abuse: Alcohol and drug abuse
• Mental Conditions: Spinal cord Injuries, strokes or brain
tumors.
• Medications: Some medicines limit the shivering action.
e.g. psychiatric medications 13
14. How is Hypothermia Treated
• Initiate First Aid & stop further heat loss.
• Hot water should not be used
• Avoid rough movements and activities because it may
cause ventricular fibrillation
• Hydrate with warm liquids, and treat any injuries
Mild Hypothermia :Use fast rewarming methods
Severe Hypothermia: Use slow rewarming methods
• Handle victim gently during CPR, intubation, BVM 14
15. Hypothermia: Known No’s
• No rush &o rough handling
• No body to body re-warming - rescuer risk
• No giving up until they are warm and dead
• No immediate rewarming
• Individuals with a detectable heart beat, no matter how
slow, should not receive CPR or rescue breathing
• If the victim is breathing, oxygen administration at a
generous flow rate prior to transport may reduce the risk
of fibrillation.
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16. Conclusion
• Hypothermia is rare but treatable
• Requires good planning and good judgment.
• Wear appropriate clothing for the weather.
• Prepare for the worst when enjoying an outdoor activity if
cold weather is a possibility.
• Communities ensuring safe housing for poor and elderly
people.
• Shut-ins should have routine social service or family
contacts.
• Prevention is still the best and ….
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historically, hypothermia has been described widely in maritime accident victims and war casualities. The aviation litterature as a matter of fact is very rich in case reports on hypothermia. Much earlier, in 218 B.C., Hannibal, for those who heard about him, this conquerent who fought against the Rome Empire, (change slide!) lost half of his army of 46 000 soldiers in the cold, while traversing the Pyrenees (PIreniz) with his elephants.
hypothermia < 35…though you will read in the ACLS (and it’s the only place), it is < 36 degrees. I haven’t seen one single article where they define hypothermia as < 36 in there methodology…I just wanted to mention it. There is a little bit of variability in these definitions depending on where you read… (Severe : 20-28 C) (Profound : 14-20 C) (Deep : < 14 C)
So the clinical presentation for mild hypothermia… More or less like a drunk guy…without the breathe…
multiple case reports of patients with temperature in low 20’s who survived neurologically intact. 1 case: 13.5 (peds). That’s why many people claims that you are not dead until warm and dead…
Radiation ~60%, Conduction and convection, ~15% (conductive heat loss increases 25 times in cold water). Baseline 25% heat loss from respiration and evaporation affected by relative humidity and ambient temperature
good outcome have been reported… Differential diagnosis because it can manifests by many different ways from tachy/bradycardia to a coagulopathy… 5th vital sign after HR, RR, BP, O2sat, … … and…don’t forget, …