After invading the body, it is mainly metabolized in the liver and quickly excreted. The main target organ is the liver, and the kidney is also damaged to a certain extent, and it is moderately poisoned.
clinical picture
Acute poisoning usually occurs 6 ~ 12 hours after respiratory inhalation; Skin invasion, the incubation period can be longer, and there are reports of poisoning after skin burns are basically healed. For subacute poisoning cases, the time from exposure to onset is 2 ~ 4 weeks.
clinical features
Irritation symptoms: DMF vapor has mild and moderate irritation to eyes and upper respiratory tract.
Skin: Contaminated skin can cause mild to severe burns, wrinkled skin, pale face and burning sensation. In severe cases, it can make the skin swell, and in severe cases, it can burn.
Eyes: polluted eyes cause burning pain, tears and conjunctival congestion; Severe cases can cause corneal necrosis.
Gastrointestinal symptoms: patients often have loss of appetite, nausea, vomiting, abdominal discomfort and constipation, and a few cases have upper-middle abdominal pain.
Liver: In acute poisoning, liver damage is often prominent. The patient has obvious fatigue, swelling and pain in the right upper abdomen, discomfort, jaundice, gradually enlarged liver and tenderness. The routine examination of liver function is abnormal, among which the serum transaminase is obviously increased. The lesions are generally not serious, and can be gradually relieved after treatment, and the condition can be fully recovered within a few weeks.
Severe acute poisoning: severe toxic liver disease, and occupational poisoning is rare. Contact with high concentrations, especially those with serious skin pollution, should be alert to serious poisoning.
Life poisoning: There was once a patient with chronic ulcerative colitis who used DMF enema as a therapeutic drug and caused liver disease. The condition gradually worsened, similar to subacute hepatic necrotizing hepatitis, and hepatic coma occurred within 2 weeks, with a dangerous prognosis.
Special risk: patients with liver diseases of various reasons are sensitive to DMF.
diagnose
Clinical manifestations: gastrointestinal symptoms first, then toxic liver disease.
Biological detection: determination of dimethylformamide in blood or monomethyl formamide in urine as an indicator of absorption products.
Abnormal liver function test can be used as an index of liver lesions.
It is generally not difficult to make a diagnosis by comprehensively analyzing the location and clinical characteristics of the disease. When a group of people have liver diseases one after another, it is necessary to make on-the-spot investigation and epidemiological investigation in order to make a correct diagnosis.
differential diagnosis
Mainly differentiated from acute viral hepatitis, toxic liver disease caused by this product is often misdiagnosed as viral hepatitis, and more attention should be paid to it in the early stage. The key points of differential diagnosis are to pay attention to inquiring about the contact history of poisons, on-site investigation, closely observing the progress of the disease and correctly evaluating the diagnostic significance of serum markers of viral hepatitis.
In addition, it should be differentiated from drug-induced liver disease.
deal with
This product has no specific antidote.
When the skin is polluted, rinse thoroughly with plenty of water. If the skin burns, please refer to: .
When eyes are polluted, rinse them thoroughly with clear water, and have an eye examination if necessary.
Oral poison must be thoroughly gastric lavage.
Main points of treatment
Pay attention to toxic liver disease: A. Stay in bed. A light and digestible diet rich in vitamins. C. give vitamin b group. Inject glucose solution. E. Choose one or two commonly used therapeutic drugs such as yeast tablets, Gantaile, Gan Le, vitamin C, choline, etc. F. Glucocorticoid can be used in severe patients. Dexamethasone is generally 20 ~ 60mg/ day, and it is injected into muscle for several times for less than one week, and gradually reduced. Pay special attention to side effects, especially gastrointestinal bleeding.
Other symptomatic and supportive treatments. Syndrome differentiation and treatment in traditional Chinese medicine. See:; .
Matters needing attention
1 can show the liver lesions after skin burn healing, so we should pay attention to it in the early stage and give necessary treatment, such as vitamin B, C and glucose. And closely observe whether there is delayed liver disease.
When this product is used in small factories, we don't know its toxicity and pay attention to protection, so the reports of acute poisoning have increased. The health department should strengthen education, introduce the poisoning symptoms caused by this sample to doctors and infectious disease doctors, and improve the quality of early diagnosis and treatment.
standard
Hygienic standard of workplace air: China MAC 10 mg/m 3. American ACGIH TLV-TWA 30mg/m3 (10ppm) (skin)
Hazard code: GB3.3 class 33627. UN No.2265 .IMDG Code 3 132-2 Page, Category 3.3.
Dimethylformamide (DMF) is a transparent liquid, which is miscible with water and most organic solvents. It is a common solvent for chemical reactions.
Pure dimethylformamide is tasteless, but industrial or deteriorated dimethylformamide has a fishy smell because of impurities containing dimethylamine.
The name comes from the fact that it is a dimethyl substitute of formamide (amide of formic acid), and both methyl groups are located on the N (nitrogen) atom. Dimethylformamide is a polar (hydrophilic) aprotic solvent with high boiling point, which can promote the reaction mechanism of SN2.
Dimethylformamide is made of methyl formate and dimethylamine. Dimethylformamide is unstable (especially at high temperature) in the presence of strong alkali such as sodium hydroxide or strong acid such as hydrochloric acid and sulfuric acid, and it is hydrolyzed into formic acid and dimethylamine. Hydrogen cyanide +H2O-(CH3)2NH+HCOOH.