Froz bite events often occur in subtropical areas. Froz bite will cause tissue freezing. ice crystals are formed between the cells and grow at the expense of intracellular water. The resulting cellular dehydration combined with ischemia due to vasoconstriction and increased blood viscosity is a mechanism of tissue injury. Skin and muscle is much more susceptible to freezing damage of tendons and bones, which explains why the patient can still move.
cold exposure, the effect can be magnified by moisture or wind. For example, the effect of cold on the skin is the same as the air temperature by 6.7 ° C) and winds of 40 miles per hour as the air temperature of -40 ° C and only 2 miles per hour winds. Contact with metals or petrol in very cold weather can cause almost frozen for a moment. Increased risk of froz bite by general hypothermia, which results in peripheral vasoconstriction as part of a mechanism to maintain core body temperature.
Two related injuries, trench foot and immersion foot, involving prolonged exposure to cold and wet in above freezing (eg, 10 ° C). The resulting tissue damage produced by ischemia.
Frostnip, minor variants of this syndrome, is the temporary blanching and numbness in the open part that can develop into a froz bite if not promptly detected and treated. It often appears on the tip of the finger, ear, nose, chin, or cheeks and should be managed by rewarming through contact with warm parts of the body or hot air.
Frozen sections numb, painless, and white or waxy appearance. With the cold sting of a shallow, only skin and subcutaneous tissue is frozen, so the network is still compressible under pressure. Deep froz bite involves freezing the tissue beneath, which teaches that the consistency of wood to the end.
After rewarming, the clot becomes mottled blue or purple and painful and tender. Blisters appear that may take several weeks to complete. section becomes edematous and painful different.
Who suffered frostbite should direwarmed (thawed) water soak 40 to 42.2 ° C for 20-30 minutes. victims should be permanent until warm and rested. It is far better to continue to walk on frozen feet even during long hours than those in remote cold regions where definitive care can not be given. If no thermometer is available, the water temperature must be adjusted to be warm but not hot for the normal hand. Never use frozen sections to test the water temperature or exposed to direct heat sources like fire. Compounding the risk of serious injury by the method of thawing in addition to soaking in warm water.
Wa laupun disbursement has been completed, the patient should remain lying down and the wound was left open to air, protected from direct contact with the sheets, clothes, etc.. Blisters should be left intact and debridement of soft leather with a soak in a whirlpool bath for about 20 minutes twice a day. Do not rub or massage of the injured part should be allowed, and topical ointments, antiseptics, etc., which are worthless. Vasodilating agents and surgical sympathectomy are not shown to improve healing.
Tissue healing gradually, and the dead tissue will be restricted and will usually swamp spontaneously. At the beginning of the course, almost impossible, even for someone with considerable experience in the froz bite treatment, to assess the depth of injury: a preliminary assessment of the least likely to detect the extent of damage. Therefore, debridement therapy should be avoided even if the evolution of the injury requires many months. Surgery may be indicated to remove a circular constricting eschars, but rarely have spontaneous gangrenous tissue separation process will be facilitated through the surgery. Even in severe injury, amputation is rarely indicated unless the previous 2 months super invasive infection.
A fracture or dislocation creates problems that are challenging and complex. Dislocations should be reduced immediately after heating. open fractures require surgery, but closed fractures should be managed with a back slab.
After the eschar separates, leather note to be shrinking, shiny, soft, and sensitive to cold, sometimes it shows a tendency to sweat more easily. Gradually returned to normal, but the pain when exposed to cold can last forever.
Prognosis for normal function is excellent if proper care is provided. People who have recovered from the froz bite have increased susceptibility to other froz bite injury on exposure to cold.
Accidental Hypothermia state of decline in core body temperature is controlled below 35 ° C with exposure to cold. This syndrome can be seen in older people living alone in the house is not hot enough, the alcohol-exposed to cold during the party, to those involved in winter sports. Alcohol meprecipitasi hypothermia by producing sedation (inhibits shivering) and dilation of the skin. other sedatives, tranquilizers, and antidepressants are sometimes involved. Predisposing illnesses including hypothermia myxedema, hypopituitarism, adrenal insufficiency, cerebrovascular insufficiency, mental disorders, and cardiovascular disorders.
The liver is the organ most sensitive to cooling and is subject to ventricular fibrillation or asystole when the temperature drops to 21-24 ° C. Hypothermia affects the dissociation curve of oxyhemoglobin, so less oxygen is released to the network. Cardiac arrest may cause death in less than 1 hour in a shipwreck victims immersed in cold water (6.7 ° C). Increased capillary permeability, which is spoken by the general and pulmonary edema, liver, and kidney dysfunction, may develop as the patient rewarmed. Disseminated intravascular coagulopathy and coagulation are sometimes seen. Pancreatitis and acute renal failure is common in patients on admission temperature below 32 ° C.
A. Symptoms and Signs
Mentally depressed patients (drowsy, stuporous, or coma), cold, and pale to cyanotic. Clinical findings are not always obvious and can be mistaken for the effects of alcohol. Core temperature ranges from 21-35 ° C. Shivering was not present when the temperature is below 32 ° C. Respiration slow and shallow. Many patients with bronchopneumonia. Blood pressure is usually normal and slow heart rate. When the core temperature drops below 32 ° C, the patient may appear dead. Extremities may be frozen or frozen.
B. Laboratory Findings
Dehydration can increase blood concentrations of various constituents. plain of severe hypoglycemia, and unless detected and treated promptly, can be a dangerous bad as rewarming produces chills. Serum amylase increased at about half the cases, but the autopsy revealed that not necessarily reflect the pancreatitis. Diabetic ketoacidosis management problem in some patients with high amylase values in insert. AST, LDH, and CK enzymes are usually high but not too meaningful. ECG showed PR interval prolongation, interventricular conduction delay, and the pathognomonic J waves at the junction of the QRS complex and ST segment.
Hypothermia patients should not be considered dead until all the measures fail to capture cardiopulmonary resuscitation in hypothermia heavy long-compatible with complete recovery.
Mild hypothermia (body temperature 32-35 ° C) can be treated in most cases with passive rewarming clothing (heavy and blankets in a warm environment) for several hours, especially when the patient was shivering. The patient's temperature should be continuously monitored with a rectal or esophageal probe to reach normal body temperature. Because the volume of intravenous fluids needed for resuscitation are often large, their temperature can affect the results. As a result, intravenous fluids should be heated with a heat exchanger during administration.
Active rewarming is indicated for temperatures below 32 ° C, cardiac instability, or failure of passive rewarming. The method involves soaking in hot baths, hot air, pleural lavage, peritoneal lavage, and blood warming with Extracorporeal bypass machine. Active external rewarming is most often done by immersion in a (warm 40-42 ° C) water bath, which will increase body temperature by 1-2 degrees per hour speed. Loss of this method is that the core temperature may continue to decrease after initiation of rewarming efforts (known as the after-drop), which is associated with worsening of heart function.
Closed pleural irrigation should be done by flushing the right hemithorax with warm (40-42 ° C) saline solution through the tube torakostomi two large, one anterior and other posterior. Rewarming by peritoneal lavage involves the administration of warm (40-45 ° C) crystalloid solution, 6 L / hr, which increases core temperature by 2-4 degrees per hour.
Active core rewarming with partial cardiopulmonary bypass, the most efficient technique, indicated for patients with severe hypothermia and ventricular fibrillation or who had frozen feet. At flow rates of 6-7 L / min, core temperature can be raised by 1-2 ° C every 3-5 minutes.
In severe cases, endotracheal intubation should be used for better management of ventilation and protection against aspiration, common lethal complication. Arterial blood gases should be monitored frequently. Bretylium tosylate in the initial dose of 10 mg / kg is the best medicine for ventricular fibrillation. Antibiotics are often indicated to live with pneumonitis. Serious infection is often unsuspected on admission, and delay in appropriate therapy may contribute to disease severity. Hypoglycemia calls for the provision of 50% glucose solution intravenously. Fluid administration should be measured by the central venous pressure or pulmonary artery wedge, urine output and other circulatory parameters. Increased capillary permeability following rewarming predisposes to the development of pulmonary edema and compartment syndrome in the leg. To minimize complications, central venous or wedge pressure should be kept under 12-14 cm of water. Drugs should not be injected into the network edge, because the absorption will not occur while the patient is cold and because the drug can accumulate to produce serious toxicity occurred rewarming.
As a result of rewarming, the patient must be continually reassessed for signs of concurrent disease that may have been covered by hypothermia, especially myxedema and hypoglycemia. Any failure should be explained to respond suggest adrenal insufficiency.
Survival can be expected in only 50% of patients whose core temperature drops below 32.2 ° C. Living with the disease (eg, stroke, neoplasm, myocardial infarction) is common and increases mortality to 75% or more. Survival did not correlate closely with the absolute lowest temperature reached. Death may result from pneumonitis, heart failure, or renal insufficiency.