Description frostbite
Frostbite rank among dermatoses caused by thermal effects. It is the damage to the skin, which is exposed to low temperatures for longer periods. The fundamental difference between frostbite and burns except for the temperature which acts on the body, is the fact that the origin and course of frostbite is highly dependent on the body’s immunity.
Risk factors for frostbite
Unique is the risk of circulatory disorders of the extremities, which may be congenital or may be caused by medications or diabetes (diabetes mellitus). And other common risk factor is smoking.Frostbite most commonly affects the toes, hands, ears, nose.
The influence of cold on the body can be divided into general (establishment of hypothermia) and local (frostbites). For an explanation of frostbite we have more familiar with the effects of cold on the body, and also with how the body can defend against the cold.
Chill effect on the human body as a significant stressor. Stressor is defined as a factor that induces the body in a state of inner tension – stress. The organism has created stress response, which is called the general adaptation syndrome, which includes a uniform neurohormonal response (brain activity and hormones).
Chill induced in the body response, which is to increase sympathetic tone vegetative system, resulting in vasoconstriction of blood vessels in the skin (vasoconstriction = narrowing of the cross section of the vessel, which gets into the tissue less blood).
Normally blood returns to the heart through the veins, which produces the extremities two systems: one surface that we see on his legs, and a deep system, which runs along the arteries between the muscles. Vasoconstriction redirects blood in the deep veins where blood which is relatively cooler (returning from the extremities towards the heart), heats the blood arteries which are adjacent.
This is the first adjustment mechanism to cold. The body in this case has only one purpose, namely to keep the body’s core temperature, which holds the key bodies for life. Limbs in this regard are not a priority for the body.
If a person moves in the cold longer, blowing on his wind and rising humidity of the ambient air, a situation occurs that alone will not be sufficient vasoconstriction of blood vessels and core body temperature will decline. The body has so far hindered say passively, ie so that prevent heat loss.However, the body can create extra heat. It happens so that the cold one tries to move as much as possible, and further the formation of the shivering. Both of these processes are very energy intensive, but can increase heat production of several minutes.
If it fails, this mechanism leads to the so-called. Hypothermia – decrease in body core temperaturebelow 35 ° C. When core body temperature drops below 34 ° C leads to disorders of consciousness, about two degrees less arises unconscious. Man dies when the body’s core temperature drops to 24 ° C due to respiratory failure or heart failure.
For comprehensive information on the problem, it should be noted that newborns have a different strategy to deal with the cold. The child is unable to end the first month of life to create warm tremor. In order to create a warm, has a special fat tissue, which is called brown adipose tissue.The metabolism of this tissue does not produce energy primarily for humans (like normal adult adipose tissue), but the heat.
Despite this ingenious mechanism to generate heat, a small child very prone to chills. There are two reasons, firstly, the child is not properly developed thermoregulatory mechanisms, and secondly the weight of the newborn small compared to its relatively large body surface so easily from cold.
Signs and symptoms of frostbite
Frostbite or congelationes arise when local exposure to cold at the most peripheral areas of the human body, which are at the expense of vital organs less heat supply blood from the body core.
Manifestations of the disease are divided into three groups, hence the designation then frostbite 1st, 2nd and 3rd degree.
Frostbite First Instance
The first stage will be reflected constriction of blood vessels in the skin (see above), resulting in awhitening of the affected skin. Subsequent opening of blood vessels when in gets more blood, is the characteristic redness – dermatitis acuta erythematosus: painful and bounded erythema, which is accompanied by swelling.
Second-degree frostbite
The second stage, referred to as dermatitis bullosa acuta, characterized in that on the affected skin forms blisters with bloody content.
Third degree frostbite
Third and heaviest degree is referred to as dermatitis acuta necrotica. This stage is characterized by the formation of necrosis. The affected tissue area struck deeper subcutaneous tissue damaged afferent vessels. Leather is insensitive, and it is on blackening.
Oznobeniny (perniones)
Perniones are defined as skin changes that are caused by the cold in susceptible individuals with peripheral vascular disorders. Perniones arise mainly from the skin of their hands after repeated prolonged exposure to the cold (temperatures are above freezing).
Predisposing factors are circulatory disorders, increased sweating, etc. Are most often affected women.
Clinical findings are highlighted spots or pimples that are cool and warm red-light red. Perniones found on the skin of hands, but also on the feet, legs, nose. Patient symptoms can itch, pallets.Symptoms worsen in the heat or during rapid temperature fluctuations.
Treatment is vasodilating preparations (pentoxiphylin) and guidance to the patient rather stayed in a warmer environment.
frostbite treatment
For the treatment of frostbite is important in its own first aid to help prevent frostbite or reduce their impact. The best prevention is therefore not to move in the mountains, and if so, only on marked trails, and keep account of the weather and also on your own physical abilities.
Light frostbite is relatively easy to treat, and to get the leg warmer environment (above 15 ° C), in no case, however, do not expose it to direct heat (fire) or at the moment extreme temperatures (heating, hair dryer). It is important to realize that frostbite, although slight, is significant damage skin, which becomes susceptible to further damage (and heat, cold, infections).
Severe cases are treated as in burns, applied to the wound with saline, which is bounded at the correct temperature. It must also prevent ingress of bacteria into the skin.
In necrotic areas can be performed cuts, which releases the pressure which would cause ischemia. After some time removes necrotic skin and covers the graft. For completely dead fingers or other peripheral tissues is performed amputation.
Overall, the patient is given fluid (infusion), painkillers.
Other names: congelatio, pernio, congelationes, dermatitis acuta erythematosus, frostbite first degree, second degree frostbite, chilblains third degree acuta dermatitis bullosa, dermatitis acuta necrotica, oznobeniny, perniones
