frozen
Introduction
Introduction to freezing Freezing, also known as accidental hypothermia, is a serious systemic disease caused by hypothermia caused by cold environment and mainly caused by nervous system and cardiovascular damage. Frostbite (forstbite) is a local tissue damage caused by cold, which is more common in limbs and face. Freezing often occurs when staying in a cold environment and working for too long, and its lack of warmth and cold protection measures can also occur when it is buried in snow or immersed in ice water. Patients with frozen stiffness have headaches, anxiety, muscles and joints in the limbs, skin pale and cold, rapid heartbeat and breathing, increased blood pressure, lethargy when the body temperature is lower than 33 °C, memory loss, heartbeat and respiratory slowness, weak pulse Feeling and unresponsive, body temperature below 26 °C, coma, decreased cardiac output, decreased blood pressure, arrhythmia, and even ventricular fibrillation, hepatocyte hypoxia, affecting glucose metabolism, lowering blood glucose and increased potassium, cold affects kidney The reabsorption of tubule water and sodium increases the amount of urine, reduces blood volume, and stops the heartbeat at 20 °C. basic knowledge The proportion of illness: 0.001% Susceptible people: no specific people Mode of infection: non-infectious Complications: thrombosis, arrhythmia, pericarditis
Cause
Cause of freezing
Cold environment (30%):
Freezing often occurs when staying in a cold environment and working for too long, and its cold and cold measures are insufficient. It can also occur when it is buried in snow or immersed in ice water. Frostbite can occur at a low temperature or even Above 0 °C, often caused by wearing tight or wet shoes, old people, infants, extremely debilitated and chronic cardiovascular disease, forebrain pituitary and hypothyroidism, cerebrovascular accident sequelae, occasionally under temperature It can also cause freezing and frostbite in the room, and it is more likely to induce the disease due to hunger, fatigue and alcohol.
Physiological effects (30%):
Freezing is a skin temperature and deep-temperature receptor that stimulates the anterior view of the brain. The adrenergic sympathetic nerve contracts the surface to maintain body temperature, while the motor nerves increase muscle tension and jitter to generate heat, but the added heat. They are all limited, only 40% to 60% more than in the quiet state. The cold increases oxygen consumption and cardiac output. In the environment of 5 °C, the oxygen consumption is increased by about 3 times, and the cardiac output is increased by 95%. The cold affects consciousness and thinking activities, reduces the reactivity and working ability to the outside world, when the cold continues to exist, the body temperature drops below 35 ° C, called low temperature, low temperature affects brain and heart function, and impedes energy metabolism such as glucose, body temperature is 26 At ~33 °C, cold directly acts on the myocardium, causing slow heartbeat and arrhythmia; at 17-26 °C, hemoglobin and oxygen have increased affinity, oxygen release is reduced, and tissue is hypoxic; at 12 °C, cell membrane sodium channel is blocked, Sodium ions can not enter the cell, so that the muscle fiber has no stress reaction, and there is sensory and motor nerve paralysis. The surrounding blood vessels dilate and cause heat loss, further causing the body temperature to drop. If the hypothermia is short, the function of the nerves and muscles can be restored when the body temperature rises. If the hypothermia lasts for several hours, the nerves and muscles will undergo degeneration. Even if the body temperature returns to normal, its function is difficult to recover. After thawing, thrombus is easily formed in the lumen of the blood vessel and tissue ischemic necrosis is caused.
Vascular contraction (30%):
Frostbite is a local temperature that is too low, resulting in local vasoconstriction, post-expansion, increased capillary wall permeability, plasma exudation, tissue edema, intravascular blood concentration and vascular wall damage, thrombosis leading to tissue necrosis, lesions may only Limited to the skin or involving deep tissues, including muscles and bones.
Prevention
Frozen prevention
Prevention is mainly to keep warm, local application of frostbite syrup or ointment, blister should not be punctured, let it dry naturally, to prevent secondary infection of the wound.
Complication
Frozen complication Complications thrombosis arrhythmia pericarditis
Old people, infants, extremely debilitated and chronic cardiovascular disease, forebrain pituitary and hypothyroidism, cerebral vascular sequelae, occasionally in the low temperature room can also occur frozen and frostbite.
Symptom
Symptoms of freezing symptoms Common symptoms Hand frostbite coma face cracked face frostbite foot frostbite wet gangrene reaction slow skin pale secondary infection dry gangrene
Patients with frozen stiffness have headaches, anxiety, muscles and joints in the limbs, skin pale and cold, rapid heartbeat and breathing, increased blood pressure, lethargy when the body temperature is lower than 33 °C, memory loss, heartbeat and respiratory slowness, weak pulse Feeling and unresponsive, body temperature below 26 °C, coma, decreased cardiac output, decreased blood pressure, arrhythmia, and even ventricular fibrillation, hepatocyte hypoxia, affecting glucose metabolism, lowering blood glucose and increased potassium, cold affects kidney Reabsorption of tubule water and sodium increases urine volume, blood volume decreases, cardiac arrest at 20 °C, hypothermia can also cause gastric mucosal erosion and hemorrhage, and pancreatic inflammation. Thrombosis and tissue ischemic necrosis can occur after freezing and freezing.
Frostbite often occurs in the fingers, toes, ear shells and nose, and can also occur in the wrist, forearm, foot, face, elbow, ankle, etc., and can also occur in the buttocks, abdominal wall and external reproductive organs when trapped in snow. .
The skin of the frostbite is pale and cold, painful and numb. It is clinically divided into four degrees according to the degree of damage. The first and second degrees are mainly tissue blood circulation disorders, and the third and fourth degrees have tissue necrosis of different depths.
Once: shallow skin frostbite, pale skin at the beginning, followed by blue-violet, after the redness, itching, tingling and paresthesia.
Second degree: for the whole layer of frostbite of the skin, in addition to redness and swelling, blistering occurs, and the blister is easily infected after being broken. If there is no infection, the water will dry up and become sputum after 2 to 3 weeks.
Third degree: frostbite affects the whole layer and subcutaneous tissue of the skin. The skin changes from pale to blue, and turns to black. The feeling disappears. The necrotic tissue falls off to form an ulcer. It is easy to secondary infection. It can leave scar after healing and can affect function. .
Four degrees: skin, subcutaneous tissue, muscles, and even bones are frostbitten. The frostbite is dark gray, edema and blisters on the edges, and the feeling and movement are completely lost. After 2 to 3 weeks, the necrotic tissue is clearly defined and forms dry gangrene. There are edema and secondary infections turned into wet gangrene, often with disabilities and dysfunction, a small number of pneumonia, pericarditis and other infections.
Examine
Frozen check
Patients with frozen stiffness have headaches, restlessness, muscles and joint stiffness in the limbs, pale and cold skin, rapid heartbeat and breathing, and increased blood pressure. When the body temperature is lower than 33 ° C, there is drowsiness, memory loss, heartbeat and respiratory slowness, weak pulse, feeling and unresponsiveness. Body temperature below 26 ° C, coma, decreased cardiac output, blood pressure, arrhythmia, and even ventricular fibrillation. Hypoxia in hepatocytes affects glucose metabolism and lowers blood glucose and blood potassium. Cold affects the reabsorption of renal tubule water and sodium, resulting in increased urine output and reduced blood volume. The heartbeat stops at 20 °C. Low temperatures can also cause gastric mucosal erosion and bleeding as well as pancreatic inflammation. Thrombosis and tissue ischemic necrosis can occur after freezing and freezing.Diagnosis
Frozen diagnosis
The skin of the frostbite is pale and cold, painful and numb. It is clinically divided into four degrees according to the degree of damage. The first and second degrees are mainly tissue blood circulation disorders, and the third and fourth degrees have tissue necrosis of different depths.
Once: shallow skin frostbite, pale skin at the beginning, followed by blue-violet, after the redness, itching, tingling and paresthesia.
Second degree: for the whole layer of frostbite of the skin, in addition to redness and swelling, blistering occurs, and the blister is easily infected after being broken. If there is no infection, the water will dry up and become sputum after 2 to 3 weeks.
Third degree: frostbite affects the whole layer and subcutaneous tissue of the skin. The skin changes from pale to blue, and turns to black. The feeling disappears. The necrotic tissue falls off to form an ulcer. It is easy to secondary infection. It can leave scar after healing and can affect function. .
Four degrees: skin, subcutaneous tissue, muscles, and even bones are frostbitten. The frostbite is dark gray, edema and blisters on the edges, and the feeling and movement are completely lost. After 2 to 3 weeks, the necrotic tissue is clearly defined and forms dry gangrene. There are edema and secondary infections turned into wet gangrene, often with disabilities and dysfunction, a small number of pneumonia, pericarditis and other infections.
