What Is Chymopapain?

Paraquat, whose chemical name is 1-dimethyl-4-4-bipyridyl cation salt, is a fast-killing herbicide with contact killing and certain systemic action. Can be quickly absorbed by the green tissue of the plant, causing it to die. Has no effect on non-green organizations. It quickly combines with the soil in the soil to passivate, and has no effect on plant roots and perennial underground stems and perennial roots.

Paraquat

Paraquat, chemical name is 1-dimethyl-4-4-bipyridine cation salt, is a fast

Quick-acting

Controls various annual weeds; right

1. Use in orchards, mulberry orchards, tea orchards, rubber orchards, and forest belts: When weeds are in full bloom and in a vigorous period, use 100-200 ml of 20% water solution per acre and 25 kg of water, spray the weed stems and leaves evenly. When weeds grow to more than 30cm, the dosage should be doubled.

Paraquat is biocidal

Paraquat is also known as fast-to-grass. This product has two kinds of dichloride and methyl disulfate, the former code is PP148, the latter code is PP910, chemically belongs to the bipyridine heterocyclic compound, the chemical name is 1,1-dimethyl-4,4-bipyridine di Chloride and methyl disulfate.

Animal experiments are highly toxic. The oral LD50 dichloride in rats is 155-203mg / kg, and the methyl disulfate salt is 320mg / kg. However, it is extremely toxic to humans. Adults estimate that the lethal amount of 20% aqueous solution is about 5-15ml or 40mg / kg. It is human

(1) The poisoning caused by absorption through various ways, the systemic poisoning manifestations are similar, but the symptoms of field spray poisoning are relatively mild, and the probability of lung damage is relatively low.

(B) local irritation symptoms:

1. Skin contamination can cause contact dermatitis and even burn damage, manifested as erythema, blisters, ulcers and necrosis. Nails can also be severely damaged or detached. Oral poisoning can sometimes cause erythema.

2. Eye contamination such as shame, tearing, eye pain, conjunctival congestion and corneal burns.

3. Nasal blood and nasopharyngeal irritation symptoms (sneezing, sore throat, congestion, etc.) and irritating cough occur in the respiratory tract.

4. Oral, throat, and esophageal mucous membranes are corroded and ulcerated by mistake.

(3) The signs of systemic poisoning affect multiple organ systems. Except for a large number of oral swallows and rapid pulmonary edema and bleeding, most of them develop progressively. Necrosis of the lungs, kidneys, liver, heart, and adrenal glands will occur within about 1-3 days. Fever may be associated with the course of the disease.

1. Digestive system: Nausea, vomiting, abdominal pain, diarrhea, and bloody stools appeared early, liver damage such as jaundice, abnormal liver function, and even liver necrosis appeared after several days (about 3-7 days). One case was reported in Dalian in China. The poisoned died of acute liver necrosis.

2. Urinary system: urinary bladder irritation symptoms such as frequent urination, urgency, and dysuria can be seen, abnormal urine tests, changes in urine output, and even occur

Diagnosis is mainly based on the history of exposure and the clinical manifestations of lung damage, with multiple systemic damage. All patients with obvious lung damage had a poor prognosis. Clinical tests and abnormalities in lung function and chest radiographs are not diagnostic specific.

Paraquat cleansing detox

1. Skin surface contamination should be removed from contaminated clothing and thoroughly washed with soapy water before washing with water. Eye contamination was rinsed with 2% -4% sodium bicarbonate solution for 15 minutes and then washed with normal saline. Sudden oral administration at the scene should immediately take soapy water, which can induce vomiting and promote paraquat inactivation. White clay (30%) or bentonite can absorb paraquat, but the effect is better if taken within 1 hour. If there is no white clay (also known as bleaching clay) or bentonite, it can also be filtered with gauze, and then take mud water. , Or use activated carbon adsorption (per 100g of white clay or bentonite can absorb about 6g of paraquat). The gastric lavage action should be gentle. The gastric lavage solution should use 2% -5% sodium bicarbonate solution plus an appropriate amount of soap or detergent to promote the inactivation of poisons. It is better to manually inject the liquid. The volume of each exchange is 200-300ml. It is not appropriate to use a perfusion-type automatic gastric lavage machine without pressure indication alarm, because paraquat has a large corrosive effect. After gastric lavage, 30g of activated carbon suspension can be given, and catharsis can be carried out with a salt laxative. Perfusion of blood poisoning is better than hemodialysis. Since the peak concentration of blood poisoning in dogs is 70-120min after poisoning, the sooner the better. Japanese scholars advocate the use of positive hemoperfusion, that is, within 24 hours after poisoning, to receive hemoperfusion treatment for not less than 10 hours, and think that starting within 15 hours of poisoning, continuous hemoperfusion treatment for 10 hours can effectively improve the survival rate of patients.

2. Clean the skin: Give the whole body a bath in time, change the clothes, remove the poison that may be left on the clothes and skin, and reduce the absorption and damage of the poison.

3. Establish venous channels quickly: Establish one or two venous channels immediately, give intravenous rehydration and other treatments, diuretic to accelerate the discharge of poisons, while maintaining electrolyte balance. Use a large number of antioxidants such as hormones and vitamins to suppress pulmonary fibrosis and use gastric mucosal protective agents.

4. Nursing of the respiratory system: As the lung injury is most severe after paraquat poisoning, it is easy to cause respiratory distress syndrome at the early stage of poisoning. Care should be taken to keep the airway open, clean the respiratory tract in time, observe the breathing, and monitor blood gas analysis regularly. Low blood oxygen saturation Low-flow oxygen can be given when needed, tracheal intubation can be performed when necessary, and ventilator assisted breathing can be given. Perform regular X-rays to check your lungs.

5. Nursing of the digestive tract: temporarily abstain from diet, leave the gastric tube, and perform gastrointestinal decompression. The movement of the gastric tube should be gentle, record the color, nature and amount of drainage fluid, and observe whether there is gastrointestinal bleeding. Oral care was carried out 3 times a day with oral solution to prevent oral infection. Observe the frequency, color, nature, and amount of stool in the patient, and make a record. Monitor electrolytes to prevent electrolyte disturbances.

6. Nursing of deep venous catheterization: Patients are instructed to rest in bed and minimize flexion movements in the right lower limb. Observe the puncture site for signs of redness, swelling, exudation and bleeding, keep the puncture catheter properly fixed, and give heparin diluent 5- 10ml sealed tube. Regular puncture point disinfection and dressing change. Observe the sensory movement of the right lower limb to prevent venous thrombosis.

7. Nursing of blood perfusion: The blood poisoning components can be removed by blood perfusion, so as to reduce or relieve the damage of the poison to the organs. During the blood perfusion, the flow rate of the blood pump should be adjusted according to the blood pressure to ensure that the patient's blood is better heparin. To prevent blood clots and air embolism, and to keep warm if necessary. Within 3 hours after the end of the perfusion, we should still pay attention to observe the patients for bleeding signs such as hematuria and local bleeding points.

8. Liver and kidney function monitoring: Paraquat has various degrees of damage to the liver and kidneys of the body. The 24-hour intake and output should be accurately recorded, and liver and kidney function should be monitored regularly. ^[4]

9. Elimination of oral poisons: Allow patients to gargle with a large amount of normal saline (250-500ml), remove poisons remaining in the oral cavity, do not induce vomiting, because paraquat can corrode the oral cavity and esophageal mucosa, and take a small amount of egg white to reduce Damage to the esophageal mucosa.

Paraquat medication

At present, there is no specific antidote, and paraquat-specific antibodies are still in the experimental research stage. The clinical drug treatments are:

1. Competitive agents: Propranolol can compete with lung-bound poisons, release them, and then clear them. Imipramine also has a similar effect, but it is difficult to make a positive evaluation of the clinical use effect.

2. High-dose cyclosexamide and dexamethasone treatment: intended to prevent pulmonary fibrosis, and was once considered to be quite effective, but after a prospective study with control observations, it was found that the mortality rate was still as high as 60%, which was not as high as the control. Significant differences, so further research and observation are needed.

3. Iron deficiency and N-acetylcysteine therapy: intended to inhibit paraquat from forming oxygen free radicals in the lungs, which has achieved certain effects in animal experiments (100 mg · kg-1 · d-1 of iron deficiency) ). Deferoxamine can effectively reduce the generation of peroxide anions and has a protective effect on lung tissue. N-acetylcysteine can increase the reducing substance glutathione in cells and counteract the oxidative toxicity of paraquat. In 1995, there were the first reports of successful clinical treatment of a large number of oral paraquat poisoning, which deserves further observation. The dosage of deferoxamine is less than 5g per day, 1g for the first time for adults, and 0.5g every 4h thereafter, and then diluted intravenously; N-acetylcysteine is used 0.25g each time. Inhaled in liquid, 3-4 times a day.

Paraquat other treatments

1. Anti-peroxidation and free radical scavengers use vitamin C, peroxidase dismutase (SOD), etc., the effect is uncertain, and most of the lung injury is ineffective.

2. Early use of corticosteroids before the occurrence of lung damage, and appropriate use of antibiotics to prevent secondary infections.

3. Rehydration and diuresis to promote excretion of poison.

4. Symptomatic and supportive treatment, special attention should be paid to handling life-threatening toxic effects such as ARDS, liver necrosis and acute renal failure.

5. Oxygen therapy should be very careful. Never use high concentration oxygen, otherwise the harm outweighs the benefits. Generally, the oxygen inhalation should be limited. Only when the oxygen partial pressure in blood is lower than 5.3kPa (40mmHg), can oxygen inhalation with concentration> 21% be used. .

6. Cases of delayed pulmonary fibrosis, which have been treated with lung transplantation abroad.