What is hypothermia ?
Hypothermia is a condition in which the central body temperature (the highest temperature in the middle of the hull) of a person has fallen so far that the normal metabolism. Body temperature varies at normal healthy people between approximately 37.5 (sometimes higher in effort) and 35.5 degrees Celsius, or sometimes somewhat lower, early in the morning during sleep. Hypothermia begins when the body temperature drops below 35 ° c. If the body temperature drops below 32 ° c, the situation is critical. Body temperatures below 27 ° c are almost always fatal without medical intervention, although there are known cases in which a body temperature of 14 ° c was survived.
Hypothermia can also be life-saving. The brain die off already when the circulation just minutes stops, but at lower temperature can that much longer (other organs are less at risk, they can be a circulatory arrest survive longer). Because of this, it is sometimes possible to survive in very cold water drowning. The victim loses consciousness and the heart rate (circulatory system) stops. The victim seems clinically dead. By the cold of the water hitting the brain not yet irreversibly damaged as fast. In some cases it is still possible to resuscitate such victims. Therefore, also in lifeless and supercooled victims sometimes said "someone is only dead if he is warm and (still) dead".
Especially small children are in favor, because by their relatively large body surface area they will cool much faster than adults.
There are roughly two types of hypothermia, acute and chronic. Acute hypothermia is the most dangerous; body temperature drops quickly, often within seconds or minutes as a victim through the ice (of a frozen lake) drops. Chronic hypothermia occurs when the body over long periods of time becomes supercooled. Someone who touches in ice cold water to water will generally within minutes too cold to swim still active. Also someone who even in Dutch inland waters to water at non-summer temperatures touches (sailors, surfers) can quickly cool down so far that swimming becomes impossible. The danger of a fatal outcome can be increased by severe fatigue or exhaustion.
Diagnosis
In practice, hypothermia is easiest to determine on the basis of the situation in which the victim is: someone who has lain in cold water, has fallen through the ice, in a snow storm is got lost or in the cold rain and wind has wrong, especially in high winds, cold weather or in the mountains, one will be created on the possibility.
In otherwise healthy people indoors is virtually impossible for hypothermia, except in very young and premature babies (usually less than 10 days old). Also in sick elderly in bad condition will be that they no fever can make more and more chronic temperature. General practitioners are sometimes called by anxious mothers at their children themselves have measured a temperature of 33 or 34 degrees or even lower. If the child is not sick and no further very young baby is concerned this almost always is based on a measurement error.
If someone has a remarkably low body temperature continuously without obvious ill have an underactive thyroid gland as a possible cause.
Hypothermia symptoms
- A low body temperature. This is the only sure and reliable symptom. Ideally located in the esophagus with a measured temperature probe; that, however, we will not find much outside specialized medical clinics. Rectal or with a special ear thermometer in the ear measured temperatures than the second choice. Measurements under the armpit, certainly in this problem, completely unreliable, measurements under the tongue are almost as unreliable. Also with a ear thermometer one can carry far too low an incorrect measuring values, e.g. for measurement, or much ear wax.
- Shivering-only in the beginning. In severe hypothermia (more than a few degrees) shivers the victim no longer.
- Dry skin-not at supercooled victims who are taken out of the water, of course.
- Sluggishness and drowsiness
- A slow heart rate and a slow breathing
- Drowsiness-sometimes mistaken for drunkenness-can develop into a coma.
- Pale skin-difficult to determine objectively (the pale skin is a result of vasoconstriction)
Hypothermia and frostbite
In addition to hypothermia may also be freezing, with fingers, toes, limbs or other body parts (such as the nose, ears, lips, penis) have cooled down such that there is ice formation in the cells has occurred. This is another problem with its own specific causes and treatment. Freezing may occur usually locally on. That someone supposedly could "freeze to death" is strictly speaking a (frequent) misconception: the death of the victim may occur with hypothermia on long before freezing (of the now defunct) occurs.
This misconception is in the Dutch language driven by incorrect translation of the English expression "to freeze to death" (to freeze means freeze, not only literally but in the spoken language also more figuratively the cold).
Hypothermia treatment
By the victim's body temperature to rise.
- Do not rub or massage, and certainly not with snow.
- No alcohol (alcohol causes vasodilation in the skin and in the limbs and leads to a warmer-feeling skin but a lower core temperature)
- Seek medical assistance
- Body heat sharing with the victim. (For example, use a sleeping bag.)
- The victim give warm drinks if conscious. Shivering takes a lot of energy to be replenished. Energising give sugary drinks or food if the victim can obtain. An unconscious never give drinking or try to stop food in the mouth.
- The victim monitor and if necessary resuscitation.
- A hot bath or shower may only if the victim is fully conscious. If the victim is too strong hypothermia, a too can fast heating and displacement or movement be perilous: then it could endanger the rescue death: the phenomenon that occurs when rescued drowning victims and victims of avalanches, since cooled down blood from the limbs then mixes with the warm bodies remained, thereby than just to cool below a critical threshold for survival.
- In the hospital, the victim is sometimes heated by peritoneal lavage with warm liquid, which is therefore being introduced into the free abdominal cavity and always refreshed. It will be the victim preferably warm humidified air breathing (hot dry air does not make sense for this, the evaporation in the respiratory system cools the victim down again). Also, a warm-up mattress under the fuselage through which hot water circulates in the hospital is a commonly used method. This method has above the warm bath is not only the advantage that it is more practical, but also that the hull is heated selectively, so that the body of the blood vessels to the limbs themselves can go open up at the moment that it is ready for it, with less danger for shock than when placed in a hot tub with not only the body but also the arms and legs.
Hypothermia in medicine
Sometimes in medicine the body deliberately cooled for a medical intervention to slow the metabolism as the surgery makes a brief cardiac arrest inevitable (surgery on the heart or the blood vessels of the brains). The surgeon then has more time. The development of the heart-lung machine that has now become a rarity. In the brain is now also experimented with cooling of the head in order to reduce the oxygen demand of the brains after the accident causing the injury subsequently would perhaps be less.
Hypothermia prevention
Hypothermia in cold environments can also be prevented by covering the head (with a hat / cap) because (when dressed people) relatively much heat is lost through the head. It goes without saying that you have to adapt your clothing to the circumstances. Absorbent clothing is a risk factor, because here in draws sweat, which then cools or natural cold water absorbs the case becomes the victim water. However, it is better to be dressed in cold water than bare - insulating clothes also insulate underwater somewhat, though they make swimming difficult. Moisture resistant or fast-drying clothes is the country's best. More layers of thin clothing are better than one thick sweater. For boaters a life jacket is always recommended - who is too cold can no longer swim, although he is an accomplished swimmer. Remember that cooling water is 30 times faster than in air, draw a wetsuit or survival suit on if there is a chance to hit the water.