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Ailmemts & Remedies

Hypothermia

Definition:-
Hypothermia  is a condition in which core temperature drops below the required temperature for normal metabolism and body functions which is defined as 35.0 °C (95.0 °F). Body temperature is usually maintained near a constant level of 36.5–37.5 °C (98–100 °F) through biologic homeostasis or thermoregulation. If exposed to cold and the internal mechanisms are unable to replenish the heat that is being lost, a drop in core temperature occurs. As body temperature decreases, characteristic symptoms occur such as shivering and mental confusion.

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When your body temperature drops, your heart, nervous system and other organs cannot work correctly. Left untreated, hypothermia eventually leads to complete failure of your heart and respiratory system and to death.

Hypothermia is most often caused by exposure to cold weather or immersion in a cold body of water. Primary treatments are methods to warm the body back to a normal temperature.

Hypothermia is the opposite of hyperthermia which is present in heat exhaustion and heat stroke. The lowest documented body temperature from which anyone has recovered was 13.0 °C (55.4 °F), in a drowning incident involving a 7-year-old girl in Sweden in December 2010

Clasification:
Normal human body temperature in adults is 34.4–37.8 °C (94–100 °F). Sometimes a narrower range is stated, such as 36.5–37.5 °C (98–100 °F). Hypothermia is defined as any body temperature below 35.0 °C (95.0 °F). It is subdivided into four different degrees, mild 32–35 °C (90–95 °F); moderate, 28–32 °C (82–90 °F); severe, 20–28 °C (68–82 °F); and profound at less than 20 °C (68 °F). This is in contrast to hyperthermia and fever which are defined as a temperature of greater than 37.5 °C (99.5 °F)-38.3 °C (100.9 °F).

Other cold-related injuries that can either be present alone or in combination with hypothermia include:

*Chilblains are superficial ulcers of the skin that occur when a predisposed individual is repeatedly exposed to cold.
*Frostbite involves the freezing and destruction of tissue.
*Frostnip is a superficial cooling of tissues without cellular destruction.
*Trench foot or immersion foot is due to repetitive exposure to wet, non-freezing temperatures

Symptoms:-
The signs and symptoms vary depending on the degree of hypothermia and may be divided by the three stages of severity.

Mild:
Symptoms of mild hypothermia may be vague  with sympathetic nervous system excitation (shivering, hypertension, tachycardia, tachypnea, and vasoconstriction). These are all physiological responses to preserve heat.  Cold diuresis, mental confusion, as well as hepatic dysfunction may also be present. Hyperglycemia may be present, as glucose consumption by cells and insulin secretion both decrease, and tissue sensitivity to insulin may be blunted. Sympathetic activation also releases glucose from the liver. In many cases, however, especially in alcoholic patients, hypoglycemia appears to be a more common presentation. Hypoglycemia is also found in many hypothermic patients because hypothermia often is a result of hypoglycemia.

Moderate:
Low body temperature results in shivering becoming more violent.(Shivering is your body’s automatic defense against cold temperature — an attempt to warm itself. Constant shivering is a key sign of hypothermia) Muscle mis-coordination becomes apparent. Movements are slow and labored, accompanied by a stumbling pace and mild confusion, although the victim may appear alert. Surface blood vessels contract further as the body focuses its remaining resources on keeping the vital organs warm. The victim becomes pale. Lips, ears, fingers and toes may become blue.

Severe:
Difficulty in speaking, sluggish thinking, and amnesia start to appear; inability to use hands and stumbling is also usually present. Cellular metabolic processes shut down. Below 30 °C (86 °F), the exposed skin becomes blue and puffy, muscle coordination becomes very poor, walking becomes almost impossible, and the victim exhibits incoherent/irrational behavior including terminal burrowing or even a stupor. Pulse and respiration rates decrease significantly, but fast heart rates (ventricular tachycardia, atrial fibrillation) can occur. Major organs fail. Clinical death occurs. Because of decreased cellular activity in stage 3 hypothermia, the body will actually take longer to undergo brain death.

As the temperature decreases further physiological systems falter and heart rate, respiratory rate, and blood pressure all decreases. This results in an expected HR in the 30s with a temperature of 28 °C (82 °F).

Paradoxical undressing:
Twenty to fifty percent of hypothermia deaths are associated with paradoxical undressing. This typically occurs during moderate to severe hypothermia, as the person becomes disoriented, confused, and combative. They may begin discarding their clothing, which, in turn, increases the rate of heat loss.

Rescuers who are trained in mountain survival techniques are taught to expect this; however, some may assume incorrectly that urban victims of hypothermia have been subjected to a sexual assault.

One explanation for the effect is a cold-induced malfunction of the hypothalamus, the part of the brain that regulates body temperature. Another explanation is that the muscles contracting peripheral blood vessels become exhausted (known as a loss of vasomotor tone) and relax, leading to a sudden surge of blood (and heat) to the extremities, fooling the person into feeling overheated.

Terminal burrowing:
In the final stages of hypothermia, the brain stem produces a burrowing-like behavior. Similar to hibernation behavior in animals, individuals with severe hypothermia are often found in small, enclosed spaces, such as under the bed or behind wardrobes.

Cause:
Hypothermia occurs when your body loses heat faster than it produces it. The most common causes of hypothermia are exposure to cold weather conditions or cold water, but prolonged exposure to any environment colder than your body can lead to hypothermia if you aren’t dressed appropriately or can’t control the conditions. Specific conditions leading to hypothermia include:

*Wearing clothes that aren’t warm enough for weather conditions

*Staying out in the cold too long

*Unable to get out of wet clothes or move to a warm, dry location

*Accidental falls in water, as in a boating accident

*Inadequate heating in the home, especially for older people and infants

*Air conditioning that is too cold, especially for older people and infants

How your body loses heat
The mechanisms of heat loss from your body include the following:

*Radiated heat. Most heat loss is due to heat radiated from unprotected surfaces of your body. Your head has a large surface area and accounts for about half of all heat loss.

*Direct contact. If you’re in direct contact with something very cold, such as cold water or the cold ground, heat is conducted away from your body. Because water is very good at transferring heat from your body, body heat is lost much faster in cold water than in cold air. Water that is 65 F (18 C) — a relatively mild air temperature — can lead to hypothermia very quickly. Similarly, heat loss from your body is much faster if your clothes are wet, as when you’re caught out in the rain.Wind.

*Wind removes body heat by carrying away the thin layer of warm air at the surface of your skin. A wind chill factor is important in causing heat loss. For example, if the outside temperature is 32 F (0 C) and the wind chill factor is minus 15 F (minus 26 C), your body loses heat as quickly as if the actual temperature outside were minus 15 F (minus 26 C).

Risk Factors:
A number of factors can increase the risk of developing hypothermia:

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*Older age. People age 65 and older are more vulnerable to hypothermia for a number of reasons. The body’s ability to regulate temperature and to sense cold may lessen with age. Older people are also more likely to have a medical condition that affects temperature regulation. Some older adults may not be able to communicate when they are cold or may not be mobile enough to get to a warm location.

*Very young age. Children lose heat faster than adults do. Children have a larger head-to-body ratio than adults do, making them more prone to heat loss through the head. Children may also ignore the cold because they’re having too much fun to think about it. And they may not have the judgment to dress properly in cold weather or to get out of the cold when they should. Infants may have a special problem with the cold because they have less efficient mechanisms for generating heat.

*Mental impairment. People with a mental illness, dementia or another condition that impairs judgment may not dress appropriately for the weather or understand the risk of cold weather. People with dementia may wander from home or get lost easily, making them more likely to be stranded outside in cold or wet weather.Alcohol and drug use.

*Alcohol may make your body feel warm inside, but it causes your blood vessels to dilate, or expand, resulting in more rapid heat loss from the surface of your skin. The use of alcohol or recreational drugs can impair your judgment about the need to get inside or wear warm clothes in cold weather conditions. If a person is intoxicated and passes out in cold weather, he or she is likely to develop hypothermia.

*Certain medical conditions. Some health disorders affect your body’s ability to regulate body temperature. Examples include underactive thyroid (hypothyroidism), malnutrition, stroke, severe arthritis, Parkinson’s disease, trauma, spinal cord injuries, burns, disorders that affect sensation in your extremities (for example, nerve damage in the feet of people with diabetes), dehydration and any condition that limits activity or restrains the normal flow of blood.

*Medications. A number of antipsychotic drugs and sedatives can impair the body’s ability to regulate its temperature.

Diagnosis:-
Accurate determination of core temperature often requires a special low temperature thermometer, as most clinical thermometers do not measure accurately below 34.4°C (94°F). A low temperature thermometer can be placed rectally, esophageally, or in the bladder. The classical ECG finding of hypothermia is the Osborne J wave. Also, ventricular fibrillation frequently occurs at <28°C (82.4°F) and asystole at <20°C (68°F). The Osborn J may look very similar to those of an acute ST elevation myocardial infarction. Thrombolysis as a reaction to the presence of Osborn J waves is not indicated, as it would only worsen the underlying coagulopathy caused by hypothermia.

As a hypothermic person’s heart rate may be very slow, prolonged palpation could be required before detecting a pulse. In 2005 American Heart Association recommended at least 30 – 45 seconds to verify the absence of a pulse before initiating CPR.

Most physicians are recommended not to declare a patient dead until their body is warmed to a normal body temperature, since extreme hypothermia can suppress heart and brain function.

Treatment:-
Aggressiveness of treatment is matched to the degree of hypothermia. Treatment ranges from noninvasive, passive external warming, to active external rewarming, to active core rewarming. In severe cases resuscitation begins with simultaneous removal from the cold environment and concurrent management of the airway, breathing, and circulation. Rapid rewarming is then commenced. A minimum of patient movement is recommended as aggressive handling may increase risks of a dysrhythmia.

Hypoglycemia is a frequent complication of hypothermia, and therefore needs to be tested for and treated. Intravenous thiamine and glucose is often recommended as many causes of hypothermia are complicated by Wernicke’s encephalopathy

Rewarming
Rewarming can be achieved using a number of different methods including passive external rewarming, active external rewarming, and active internal rewarming. Passive external rewarming involves the use of a person’s own heat generating ability through the provision of properly insulated dry clothing and moving to a warm environment. It is recommended for those with mild hypothermia. Active external rewarming involves applying warming devices externally such as warmed forced air (a Bair Hugger is a commonly used device). In austere environments hypothermia can sometimes be treated by placing a hot water bottle in both armpits and groin.  It is recommended for moderate hypothermia. Active core rewarming involves the use of intravenous warmed fluids, irrigation of body cavities with warmed fluids (the thorax, peritoneal, stomach, or bladder), use of warm humidified inhaled air, or use of extracorporeal rewarming such as via a heart lung machine. Extracorporeal rewarming is the fastest method for those with severe hypothermia.

Intravenous fluids:
As most people are moderately dehydrated due to hypothermia induced cold diuresis, intravenous fluids are often helpful ( 250-500 cc 5% dextrose and normal saline warmed to a temperature of 40-45 C is often recommended ).

Rewarming collapse:
Rewarming collapse (or rewarming shock) is a sudden drop in blood pressure in combination with a low cardiac output which may occur during active treatment of a severely hypothermic person. There is theoretical concern that external rewarming rather than internal rewarming may increase the risk. However, recent studies have not supported these concerns.

Prognosis:-
There is considerable evidence that children who suffer near-drowning accidents in water near 0°C (32°F) can be revived over an hour after losing consciousness. The cold water lowers metabolism, allowing the brain to withstand a much longer period of hypoxia. While survival is possible, mortality from severe or profound hypothermia remains high despite optimal treatment. Studies estimate mortality at between 38% – 75%. If there are obvious fatal injuries or chest is too frozen, compression resuscitation is futile

Prevention:
The Government offers extra support for some of the most vulnerable people in the form of winter fuel payments, to help keep their homes warm.

Other ways to prevent hypothermia include:
•Stay indoors as much as possible and limit your exposure to the cold
•Eat regularly and include plenty of carbohydrates (the body needs a reliable and constant energy supply to generate heat)
•Keep as active as possible
•Avoid alcohol – it causes dilation of peripheral blood vessel, increasing heat loss
•Avoid caffeine – it’s a diuretic and increases the risk of dehydration, which aggravates heat loss
•Avoid nicotine – it constricts blood vessels and increases the risk of cold damage such as frostbite
•Wear multiple thin layers of clothing that help to trap air layers and hence traps heat, rather than one thick jumper
•If you go outside, always wear a hat (it can prevent as much as 20 per cent of heat loss), scarf and gloves
•Take a flask of caffeine-free hot drink with you, and click-activated heat pads you can keep in your pockets to set off when you need them

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose

Resources:
http://www.bbc.co.uk/health/physical_health/conditions/hypothermia1.shtml
http://www.mayoclinic.com/health/hypothermia/DS00333
http://en.wikipedia.org/wiki/Hypothermia

http://trialx.com/curebyte/2011/05/22/clinical-trials-and-images-of-hypothermia/

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Ailmemts & Remedies

Frostbite

Alternative Names:- Cold exposure – arms or legs,congelatio in medical terminology

Definition:
Frostbite is damage to the skin and underlying tissues caused by extreme cold.It causes fluid in skin cells and the tissues beneath the skin to freeze and damages blood vessels. This leads to the formation of blood clots which block the flow of blood and prevent oxygen from getting to the tissues. All cells need oxygen to function properly, as without it they die.

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Frostbite  is the medical condition where localized damage is caused to skin and other tissues due to extreme cold. Frostbite is most likely to happen in body parts farthest from the heart and those with large exposed areas. The initial stages of frostbite are sometimes called “frostnip”.

Classification:-
There are several classifications for tissue damage caused by extreme cold including:

*Frostnip is a superficial cooling of tissues without cellular destruction.
*Chilblains are superficial ulcers of the skin that occur when a predisposed individual is repeatedly exposed to cold
*Frostbite involves tissue destruction.

Stages:-
At or below 0 °C (32 °F), blood vessels close to the skin start to constrict, and blood is shunted away from the extremities via the action of glomus bodies. The same response may also be a result of exposure to high winds. This constriction helps to preserve core body temperature. In extreme cold, or when the body is exposed to cold for long periods, this protective strategy can reduce blood flow in some areas of the body to dangerously low levels. This lack of blood leads to the eventual freezing and death of skin tissue in the affected areas. There are four degrees of frostbite. Each of these degrees has varying degrees of pain.

*First degree……..  CLICK & SEE

This is called frostnip and this only affects the surface skin, which is frozen. On onset there is itching and pain, and then the skin develops white, red, and yellow patches and becomes numb. The area affected by frostnip usually does not become permanently damaged as only the skin’s top layers are affected. Long-term sensitivity to both heat and cold can sometimes happen after suffering from frostnip.

*Second degree…… CLICK & SEE

If freezing continues, the skin may freeze and harden, but the deep tissues are not affected and remain soft and normal. Second degree injury usually blisters 1–2 days after becoming frozen. The blisters may become hard and blackened, but usually appear worse than they are. Most of the injuries heal in one month but the area may become permanently insensitive to both heat and cold.

*Third and Fourth degrees...  CLICK & SEE

If the area freezes further, deep frostbite occurs. The muscles, tendons, blood vessels, and nerves all freeze. The skin is hard, feels waxy, and use of the area is lost temporarily, and in severe cases, permanently. The deep frostbite results in areas of purplish blisters which turn black and which are generally blood-filled. Nerve damage in the area can result in a loss of feeling. This extreme frostbite may result in fingers and toes being amputated if the area becomes infected with gangrene. If the frostbite has gone on untreated they may fall off. The extent of the damage done to the area by the freezing process of the frostbite may take several months to assess, and this often delays surgery to remove the dead tissue

Symptoms:
The first symptoms are a “pins and needles” sensation followed by numbness. There may be an early throbbing or aching, but later on the affected part becomes insensate (feels like a “block of wood”).

Frostbitten skin is hard, pale, cold, and has no feeling. When skin has thawed out, it becomes red and painful (early frostbite). With more severe frostbite, the skin may appear white and numb (tissue has started to freeze).

Very severe frostbite(Third and Fourth degrees) may cause blisters, gangrene (blackened, dead tissue), and damage to deep structures such as tendons, muscles, nerves, and bone.

Causes:
Factors that contribute to frostbite include extreme cold, inadequate clothing, wet clothes, wind chill, and poor blood circulation. Poor circulation can be caused by tight clothing or boots, cramped positions, fatigue, certain medications, smoking, alcohol use, or diseases that affect the blood vessels, such as diabetes.

Exposure to liquid nitrogen, oxygen and other cryogenic liquids can cause frostbite.

Risk factors:
Risk factors for frostbite include using beta-blockers and having conditions such as diabetes and peripheral neuropathy.

Those with blood vessel damage caused by medical conditions, such as diabetes, or because of poor lifestyle habits such as smoking and high-fat diets, may also suffer frostbite more easily than others.

Drinking alcohol and taking certain medicines, such as beta blockers, also increases the likelihood of developing the condition.

Treatment:
When frostbite is suspected, the affected areas need to be warmed. However this should only be done when there’s no risk of them freezing again, which could cause further and possibly irreversible damage.

Ideally, warming should be performed under medical supervision, but this isn’t always possible.

It should be done slowly by immersing the areas in warm – not hot – water. As normal colour returns, they may appear red and swollen. Once this happens they can be removed from the water.

First Aid:

1. Shelter the person from the cold and move him or her to a warmer place. Remove any constricting jewelry and wet clothing. Look for signs of hypothermia (lowered body temperature) and treat accordingly.

2. If immediate medical help is available, it is usually best to wrap the affected areas in sterile dressings (remember to separate affected fingers and toes) and transport the person to an emergency department for further care.

3. If immediate care is not available, rewarming first aid may be given. Soak the affected areas in warm (never hot) water — or repeatedly apply warm cloths to affected ears, nose, or cheeks — for 20 to 30 minutes. The recommended water temperature is 104 to 108 degrees Fahrenheit. Keep circulating the water to aid the warming process. Severe burning pain, swelling, and color changes may occur during warming. Warming is complete when the skin is soft and sensation returns.

4. Apply dry, sterile dressings to the frostbitten areas. Put dressings between frostbitten fingers or toes to keep them separated.

5. Move thawed areas as little as possible.

6. Refreezing of thawed extremities can cause more severe damage. Prevent refreezing by wrapping the thawed areas and keeping the person warm. If protection from refreezing cannot be guaranteed, it may be better to delay the initial rewarming process until a warm, safe location is reached.

7. If the frostbite is extensive, give warm drinks to the person in order to replace lost fluids.

DO NOT

•Do NOT thaw out a frostbitten area if it cannot be kept thawed. Refreezing may make tissue damage even worse.
•Do NOT use direct dry heat (such as a radiator, campfire, heating pad, or hair dryer) to thaw the frostbitten areas. Direct heat can burn the tissues that are already damaged.
•Do NOT rub or massage the affected area.
•Do NOT disturb blisters on frostbitten skin.

Contact your health care professional if:-

•There has been severe frostbite, or if normal feeling and color do not return promptly after home treatment for mild frostbite
•Frostbite has occurred recently and new symptoms develop, such as fever, malaise, discoloration, or drainage from the affected body part
•Do NOT smoke or drink alcoholic beverages during recovery as both can interfere with blood circulation.

Surgery:
Debridement and or amputation of necrotic tissue is usually delayed. This has led to the adage “Frozen in January, amputate in July” with exceptions only being made for signs of infections or gas gangrene
You may click to see:Herbal treatment for frostbite

Prognosis:
A number of long term sequelae can occur after frost bite. These include: transient or permanent changes in sensation, electric shocks, increased sweating, cancers, and bone destruction/arthritis in the area affected

Research:
Evidence is insufficient to determine whether or not hyperbaric oxygen therapy as an adjunctive treatment can assist in tissue salvage. There have been case reports but few actual research studies to show the effectiveness.

Medical sympathectomy using intravenous reserpine has also been attempted with limited success.

While extreme weather conditions (cold and wind) increase the risk of frostbite it appears that certain individuals and population groups appear more resistant to milder forms of frostbite, perhaps due to longer term exposure and adaptation to cold weather environments. The “Hunter’s Response” or Axon reflex are examples of this type of adaptation.

Prevention:
Be aware of factors that can contribute to frostbite, such as extreme cold, wet clothes, high winds, and poor circulation. Poor circulation can be caused by tight clothing or boots, cramped positions, fatigue, certain medications, smoking, alcohol use, or diseases that affect the blood vessels, such as diabetes.

Wear suitable clothing in cold temperatures and protect exposed areas. In cold weather, wear mittens (not gloves); wind-proof, water-resistant, layered clothing; two pairs of socks; and a hat or scarf that covers the ears (to avoid substantial heat loss through the scalp).

If you expect to be exposed to the cold for a long period of time, don’t drink alcohol or smoke, and get adequate food and rest.

If caught in a severe snowstorm, find shelter early or increase physical activity to maintain body warmth.

Exposure to liquid nitrogen, oxygen and other cryogenic liquids should be avoided or to be handeled with care.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Resources:
http://www.bbc.co.uk/health/physical_health/conditions/frostbite.shtml
http://www.nlm.nih.gov/medlineplus/ency/article/000057.htm
http://en.wikipedia.org/wiki/Frostbite

http://healthwise-everythinghealth.blogspot.com/2010/01/frostbite.html

http://www.empowher.com/media/reference/frostbite

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