What are the symptoms of snake bite?

Snakes mostly live in cool and humid places and generally don't take the initiative to attack people. They only bite when they are accidentally trampled or bumped by pedestrians. People are easily bitten by poisonous snakes when cutting grass, chopping wood, picking wild fruits, pulling vegetables, walking and military training. When encountering natural disasters (such as floods and earthquakes), snakes will flee to a safe place to meet people, and then be bitten by snakes. Snakes can be divided into poisonous snakes and non-poisonous snakes. Most poisonous snakes have triangular heads, thin necks, short and thick tails and bright spots on their bodies. When they bite, their mouths are wide open and their teeth are long. The tooth marks left by non-poisonous snakes are very small, arranged in two rows in a figure of eight; Two large and deep tooth marks are common on the skin after being bitten by a poisonous snake. If it is uncertain whether there is a poisonous snake bite, first aid should be given according to the poisonous snake bite.

(1) symptoms

After being bitten by a poisonous snake, the speed and severity of symptoms are obviously related to the type of poisonous snake, the dosage and nature of snake venom. Of course, the location of the bite, the depth of the wound and the patient's resistance also have some influence. Poisonous snakes take the initiative to hurt people when they are hungry, which has a large amount of detoxification and serious consequences.

1. Manifestations of neurotoxic injury

The wound is numb, unconscious or only slightly itchy. The wound is not obviously red and swollen, and there is not much bleeding. About half an hour after the injury, I felt dizzy, sleepy, nausea, vomiting and fatigue. Severe cases include dysphagia, hoarseness, aphasia, ptosis and diplopia. Finally, I may have difficulty breathing, blood pressure drop and shock, leading to hypoxia, cyanosis and total paralysis. If the rescue is not timely, respiratory and circulatory failure will eventually occur, and the patient can die quickly. Neurotoxins are absorbed quickly and dangerously, and are often ignored because of mild local symptoms. The critical period is 1 ~ 2 days after injury. Once you get through this period, the symptoms will get better quickly, and there will be no sequelae after cure.

2. The manifestations of blood poisoning injury

Bite local rapid swelling, proximal development, wound pain, bleeding. The skin around the wound is often accompanied by blisters or blood bubbles, subcutaneous ecchymosis, tissue necrosis, and severe bleeding. Such as subconjunctival blood stasis, nosebleed, hematemesis, hemoptysis and hematuria. Individual patients will also have thoracic and abdominal hemorrhage and intracranial hemorrhage, which will eventually lead to hemorrhagic shock. Patients may be accompanied by headache, nausea, vomiting, diarrhea, joint pain and high fever. Because symptoms appear earlier and general treatment is timely, the mortality rate can be lower than that of patients with neurotoxic injury. However, due to the acute onset, long course of disease and long dangerous period, if the treatment is too late, the consequences will be serious. After healing, there are often local and visceral sequelae.

3. The manifestations of mixed toxic injuries

It has symptoms of neurotoxicity and blood toxicity. Local wounds are similar to those caused by blood poisoning, such as local redness, ecchymosis, blood bubbles, tissue necrosis and lymphadenitis. From the whole body, it is similar to neurotoxic injury. Neurotoxicity is still the main cause of death of this kind of wounded.

(2) treatment

After being bitten by a poisonous snake, on-site first aid is very important. Don't panic when bitten by a snake. You should examine the wound at once to determine whether the bite is poisonous or not. If there is no poisonous snake bite, no special treatment is needed, just apply some mercuric chloride or iodine to the wound. If it is definitely a poisonous snake bite or it is impossible to judge whether the biting snake is poisonous at that time, it should be treated as a poisonous snake bite: tie it to the upper side of the wound with a rubber tube, belt, cloth and rope, and take the venom out of the wound as much as possible; Rinse the wound with hydrogen peroxide or cold boiled water, salt water, etc. Then cut the skin between the teeth marks with a sterilized (such as burning) knife or blade; Fingers are squeezed on both sides of the wound to expel venom. In case of emergency, you can inhale directly through your mouth (be careful not to break it in your mouth), spit out the inhaled liquid immediately after inhalation, and rinse your mouth: if you have snake medicine or lobelia chinensis, you can apply it to the wound. After emergency treatment, the injured person should be sent to a medical unit for further treatment, as follows:

1. Stop venom absorption

After being bitten, snake venom quickly enters the body within 3 ~ 5 minutes, and effective measures should be taken as soon as possible to prevent the venom from being absorbed.

Binding method (1)- is a simple and effective method, and it is also an easy-to-do self-help and mutual rescue method on site. That is, after being bitten by a poisonous snake, immediately wrap the injured limb 5 ~ 10 cm or the root of the injured finger (toe) with cloth, towel or bandage to reduce the reflux of veins and lymph, thus temporarily preventing the absorption of snake venom. On the way to evacuation, the bandage should be loosened every 20 minutes 1 ~ 2 minutes each time to prevent congestion and tissue necrosis. After thorough debridement and taking snake pills for 3 ~ 4 hours, the bandage can be loosened.

(2) Ice compress method —— When conditions permit, ice is applied to the injured limb at the same time of dressing, so that blood vessels and lymphatic vessels contract and the absorption of snake venom is slowed down. You can also immerse the injured limbs or fingers in cold water at 4 ~ 7℃, and then apply cold compress with ice packs for 24 ~ 36 hours after 3 ~ 4 hours, but you should pay attention to keep the whole body warm while cooling locally.

(3) Braking the injured limb-walking slowly after injury to reduce the absorption of toxins. It is best to temporarily brake the injured limb and send it to the medical station. If necessary, give the patient an appropriate amount of sedative to keep the patient quiet.

2. Promote the discharge and destruction of snake venom.

Corresponding measures should be taken to promote the discharge or destruction of residual snake venom in wounds. The easiest way is to inhale through your mouth and rinse your mouth with clean water after each inhalation. Of course, the mucous membrane and lips of the sucker should not fester, and the snake venom in the wound can also be sucked out with a breast pump and cupping, and the effect is ideal. If the wound is deep and contaminated, it should be thoroughly debrided. After disinfection, the wound should be cut into the shape of "+"or "++",so that the residual snake venom can easily flow out, but the incision should not be too deep to avoid hurting blood vessels. When biting hands or feet, you can also use a triangular needle or a knife tip to pierce the proximal subcutaneous one centimeter, and then gently massage from near to far to accelerate the discharge of snake venom. After the wound is enlarged, various drugs can also be used for local wet compress or irrigation. In order to achieve the purpose of destroying or neutralizing snake venom. Commonly used drugs for external use are 30% normal saline or alum water, and 1: 5000 potassium permanganate solution and 5% ~ 10% normal saline for wound irrigation.

Local injection of trypsin has a certain effect, which can decompose and destroy snake venom, thus alleviating or inhibiting the poisoning symptoms of patients. The usage is that trypsin is dissolved in 2 ~ 4 ml physiological saline and injected around the wound basal layer, and can be repeatedly injected after 12 ~ 24 hours; Injection of furosemide, diuretic sodium or mannitol can accelerate the excretion of snake venom from the urinary system.

3. Snake venom inhibition

Oral administration and external application are mainly effective Chinese herbal medicines and snake tablets, which can achieve the functions of detoxification, anti-inflammation, hemostasis, heart strengthening and diuresis. Antivenom has been widely used in clinic and has a good effect on treating similar snake bites.

(1) various kinds of snake pills-there are more than ten kinds of snake pills used in clinic at present. When using them, it is necessary to find out which poisonous snakes are effective. Secondly, the drug should be taken early, the dose should be large and the course of treatment should be long; Finally, we must adopt other auxiliary treatments of traditional Chinese and western medicine. Nantong Snake Pill (also known as Ji Desheng Snake Pill) is the most widely used in clinical practice, and 20 tablets should be taken immediately after injury, and then 10 tablets should be taken every 6 hours until the poisoning symptoms are obviously alleviated. At the same time, the tablets are made into paste with warm water and applied around the wound and 3 ~ 4 cm above the swollen limbs. Guangzhou snake pill (He snake pill) is also effective. Take 5 tablets immediately after injury, and then take 5 tablets every 3 hours. In severe cases, the dose is doubled. In addition, Shanghai Snake Pill is mainly used to treat Agkistrodon halys, and Shesanquan Snake Pill is mainly used to treat Bungarus multicinctus and Bungarus multicinctus bites.

(2) 30-60g of fresh Lobelia Chinensis (whole herb), the juice of which is mashed and taken orally, has the functions of detoxification, diuresis and detoxification; You can also use 30 grams of fresh bird buds, mash the juice for oral administration, and apply the residue externally to prevent snake venom from attacking the heart.

(3) Serum treatment-Antivenom has a certain effect on snake bites. The curative effect of monovalent serum can be as high as 90%, while the curative effect of multivalent serum is only 50%. At present, the serum that has been successfully tested includes anti-Agkistrodon halys venom serum, anti-cobra venom serum, anti-Agkistrodon acutus venom serum, anti-bungarus venom serum, etc. Some of them are refined into powder, which is convenient for storage. Skin allergy test should be done before using antivenom, and those with negative test results can be injected.