Solvent poisoning is a pathology that occurs when inhaling toxic vapors or ingesting a chemical compound. It can occur in an acute or chronic form. The main symptoms of prolonged intoxication are tremor, memory impairment, emotional lability. With the simultaneous intake of a large amount of xenobiotic, arrhythmia develops, blockage of the respiratory center, impaired consciousness, hemolysis of erythrocytes. The diagnosis is established on the basis of anamnesis, clinical picture, data of toxicological analysis of blood and urine. Specific treatment: gastric lavage, extracorporeal detoxification, forced diuresis.
X46 Accidental poisoning and exposure to organic solvents, halogen-containing hydrocarbons and their vapors
The term “solvents” includes a large number of chemicals. This includes aliphates and aromatic hydrocarbons, alcohols, glycols, ketones, esters. Dichloroethane, trichloroethylene and carbon tetrachloride have the greatest toxicity. The lethal dose of EDC and TCE is 20-40 ml, CHU — 80-100 ml. Chronic poisoning with solvents in 85% of cases occurs in specialists engaged in construction and finishing works. Acute lesion occurs when the toxicant is ingested unintentionally or intentionally. Such exotoxicoses account for 30-40% of all industrial poisonings requiring hospitalization of the victim.
The most common cause of chronic damage is long—term inhalation of solvent vapors by painters. If during the preparation of paint mixtures a person does not use protective equipment for the nose and mouth (respirator, cotton gauze bandage, gas mask), after a few years he develops a characteristic clinical picture. Other possible ways of poisoning:
- An attempt at alcoholization. Methyl and ethyl alcohol in industrial liquids usually act as a toxicant. Ethanol causes acute conditions only with the simultaneous use of excessive amounts (4-7 g / l). Methanol is the strongest poison, severe exotoxicosis occurs with oral administration of 10-20 ml. The risk group is alcohol–dependent people.
- Substance abuse. Due to the ability of solvent molecules to adsorb on the surface of neurons and weaken their spontaneous activity, solvents are used to achieve a narcotic effect. The route of entry of the poison is inhalation, the type of lesion is chronic. The risk group is teenagers from disadvantaged families.
- An erroneous reception. Poisoning with solvents may be the result of accidental ingestion. This is possible if the toxicant is stored in food containers. Cases of erroneous use are rare, since the substance has a sharp unpleasant odor. The risk group includes children, the elderly and people suffering from mental illness.
- Accidents at work. Damage is possible if large-volume containers in which the solvent is stored at enterprises are damaged. The substance evaporates, making the air unsuitable for breathing. Such incidents are especially dangerous if the tanks with the toxicant are located inside a closed room. The risk group is employees of enterprises.
- Suicide attempt. As a means of self-retirement, dichloroethane is usually used, which has the maximum toxic ability. Death occurs within a few hours of ingestion of the poison through the mouth. The risk group is persons with mental pathology, patients with depression at the resolution stage, adolescents.
Organochlorine compounds are rapidly absorbed and distributed in tissues with a high lipid content (liver, brain, kidneys, adrenal glands, subcutaneous fat). After 6 hours, about 70% of the toxicant is deposited in the parenchyma of the organs. It binds to cell membranes, reduces the contractile capabilities of the myocardium, promotes the destruction of red blood cells. Then the poison begins to transform with the formation of toxic metabolites.
Solvent decomposition products stimulate the process of fat peroxidation, have alkating properties, and disrupt the work of enzymatic systems. In addition, the tricarboxylic acid cycle is disorganized, the calcium mechanism of cell death is activated. At the macro level, there is a central or aspiration-obturation type of respiratory disorder. Insufficiency of parenchymal organs develops, exotoxic shock, hemodynamic disorders. There is DIC, necrotic and dystrophic changes in the kidneys, liver, brain.
Solvent poisoning is divided by reasons (suicidal, domestic, professional), nature (acute, chronic), toxic agent (alcohols, aliphates, glycols), the condition of the victim (mild, moderate, severe). The classification according to the stage of the disease has the greatest clinical significance:
- Latent. It is noted only in chronic lesions. There are no obvious symptoms, but pathological changes are formed in the body. The stage can last from several months to 5-10 years, the duration depends on the intensity and frequency of the poison.
- Toxicogenic. It begins from the moment the xenobiotic enters the body, ends with a decrease in its concentration to indicators that are unable to have a toxic effect. It is characterized by the direct poisoning effect of the poison. Somatic reactions of the compensatory-adaptive type occur.
- Somatogenic. Occurs after the elimination or destruction of the poison. It is determined by the residual lesion of various body systems. Clinical manifestations are not directly related to the influence of a toxic substance. The patient develops renal and hepatic insufficiency, encephalopathy, pancreatitis, myocardiodystrophy.
Immediately after taking the poison, the pathology is manifested by the development of salivation, vomiting, nausea, dizziness, psychomotor agitation. After 1-3 hours, signs of enteritis appear: pain in the lower abdomen, flaky liquid multiple stools. Euphoria, delirium, hallucinations are noted. Later, these phenomena are replaced by depression of consciousness up to coma. Convulsions are possible. At the initial stage, the toxicant inhibits the activity of the respiratory center, which causes respiratory failure, bradypnea, apnea.
Comatose states when affected by organochlorine substances are initially caused by the direct narcotic effect of the toxicant. Then they acquire a secondary character. The duration is several hours. The patient has dilated pupils, hypertonicity of muscles, preservation of pain sensitivity, respiratory disorders, hemodynamics. In the exhaled air there is a sharp smell of used solvent, especially noticeable after taking dichloroethane through the mouth.
Exotoxic shock resulting from the use of high doses of a toxic substance is manifested by the centralization of blood circulation and hemodynamic disorders. The patient’s skin acquires a marble hue, blood pressure decreases to critical values, tachycardia is present. At the same time, DIC syndrome develops, which is more often diagnosed at the stage of hypocoagulation, accompanied by bleeding, hemorrhagic rash, blood seepage around catheters and from injection sites.
The clinical picture of the somatogenic stage differs in the polymorphism of symptoms, varies depending on the damage to certain structures, the degree of pathological changes. The most common signs of liver damage are determined (jaundice, ascites, hepatic breath, increased organ size), kidneys (decreased diuresis), heart (arrhythmias, left ventricular failure with the appearance of shortness of breath, forced position, foaming from the mouth), central nervous system (psychosis, sopor, coma).
Gradual poisoning with solvents is the cause of increased fatigue, depression, irritability. A specific cerebellar and pyramidal symptom complex is formed: headaches, tremor of the extremities, impaired coordination. There may be complaints of sleep deterioration, numbness of the legs. The earliest phenomena are sensory anesthesia, a decrease in the rate of passage of a nerve impulse. All the described signs gradually progress over several years.
The most common complication is exotoxic shock, which occurs in 35-40% of cases of severe intoxication. Pathology may be accompanied by internal bleeding on the background of pronounced coagulopathy, similar phenomena occur in 3-5% of patients admitted to the intensive care unit. The cardiotoxic effect of xenobiotic leads to the development of fibrillation followed by asystole. The toxicogenic stage is complicated by similar phenomena in 2-3% of cases.
There is a risk of acute left ventricular failure with interstitial pulmonary edema. Intracardiac conduction blockages may form up to the complete termination of the AV node. A number of patients are diagnosed with severe secondary kidney damage requiring hemodialysis. Due to the weakening of the immune system and prolonged ventilation, pneumonia occurs, the number of which reaches 18-20 for every hundred patients.
The pathology is determined by the ambulance doctor. The toxicologist of the specialized center confirms the diagnosis based on the results of a toxic-chemical and clinical-instrumental examination, a characteristic symptom complex. You may need to consult a cardiologist, gastroenterologist, differential diagnosis with food poisoning, drug poisoning, acute neurological pathology. The following types of examination are used:
- Physical. Upon examination, the doctor discovers characteristic clinical signs: the smell of a toxicant, mental agitation or depression of consciousness, a rash on the body, traces of vomit. Blood pressure is below 100/60, pulse is above 90 beats per minute. During auscultation, moist pulmonary wheezing can be heard. Of great importance in the diagnosis of chronic processes is the collection of anamnesis of life and illness.
- Laboratory. Toxico-chemical analysis of biological fluids allows you to identify a toxic substance within 1-3 days. Then a biopsy of subcutaneous fat is used for the study. In the acute stage, the patient has water-electrolyte disorders, a pH shift to the acidic side. Further, an increase in the activity of liver enzymes, the accumulation of creatinine and urea is diagnosed.
- Hardware. During sonography of the abdominal cavity, hepatomegaly is detected, rhythm disturbances (tachycardia, conduction blockages, fibrillation) are present on the ECG. Conducting an EEG in comas allows you to detect signs of suppression of the cerebral cortex. CT in chronic intoxication confirms a decrease in the volume of the brain, an increase in its ventricles.
Pathology requires complex treatment. In the toxicogenic stage, therapeutic measures are aimed at binding and removing the xenobiotic from the body. The purpose of further therapy is the correction of existing somatic disorders, restoration of all systems, elimination of clinical symptoms. The victim needs inpatient treatment in a specialized toxicology center. In the absence of such a unit, the patient is placed in the ICU of the nearest medical facility. Chronic lesions are eliminated on an outpatient basis.
The basis of first aid is gastric lavage. It is carried out by the ambulance team using a thick or nasogastric probe. Water is used as a washing liquid. The procedure is carried out until a clean substrate is obtained, this requires 12-15 liters of H2O. After the end of the manipulation, activated charcoal is injected into the stomach through a probe at the rate of 1 tablet per 10 kg of weight. For convenience, the drug can be crushed and stirred in water until a fine suspension is obtained.
Further therapy is determined taking into account the existing symptoms. Artificial ventilation of the lungs may be required by means of a combitube or laryngeal mask, administration of dopamine in order to maintain cardiac activity and blood pressure, infusion therapy with crystalloid and colloidal solutions. Transportation is carried out on a stretcher with connection to an anesthesiological monitor. Dynamic monitoring of vital signs (blood pressure, pulse, saturation, level of consciousness) is required.
Within 2 days, therapy is aimed at the speedy removal of the toxicant from the body. The victim is prescribed activated charcoal for a course of 10 days 3 times a day. In the first 4 hours, hemosorption is effective. If a lot of time has passed since the poisoning, peritoneal dialysis is used, which allows you to remove the deposited substrate from the fatty tissue of the abdomen. Forced diuresis as an independent method of detoxification is ineffective, but can be used as part of complex therapy.
The drug regimen depends on the existing damage. The patient may be prescribed glucocorticoids, proteolysis inhibitors, inotropic agents, unithiol or sodium thiosulfate. Anticoagulants are used to prevent internal combustion. B vitamins, medications designed to correct the water-salt balance, glucose are needed. Hyperbaric oxygenation with an excess pressure of 0.7-1 atmospheres is moderately effective. A diet with a reduced energy value is recommended: the amount of protein is no more than 20 grams / day, the rejection of foods rich in potassium.
Treatment of chronic poisoning is carried out on an outpatient basis or after a planned hospitalization of the victim. A complete exclusion of contact with the toxicant, a change of activity is required. The therapy is symptomatic, the use of antidotes is unreasonable. It is necessary to administer nootropic drugs, antioxidants, antidepressants, analgesics, medications that improve the conduct of the nerve impulse. The measures carried out stop some of the symptoms, there is no complete recovery of the affected functions.
Patients receive inhibitors of microsomal enzymes that slow down the rate of toxicant metabolism. Attempts are being made to treat the victims with the help of amidoisovaleric acid, acetylcysteine, vitamin “E”. Taking into account the fact that part of the xenobiotic is released through the lungs, the method of moderate hyperventilation is considered justified. The above methods are effective, but insufficiently studied for widespread use.
Prognosis and prevention
The prognosis for poisoning with dichloroethane, carbon tetrachloride, trichloroethylene is sharply unfavorable. The mortality rate reaches 60% of the total number of hospitalized patients. Methanol intoxication is partially corrected with intravenous administration of ethyl alcohol, which increases the chances of survival. When ingesting ethylene glycol, exotoxicosis with esters, mortality does not exceed 20-25%. Ethanol damage causes death in no more than 1-3% of cases, and complete recovery is more often observed in the long-term period.
Poisoning with solvents of a chronic type usually does not lead to the death of the patient, but there is also no sufficient restoration of the functions of the central nervous system. Observations show that 2 years after the cessation of contact with the toxic substance, subjective symptoms decrease, the degree of brain atrophy and decrease in intellectual functions remains the same in 70%, progresses in 30% of cases. In the interval of 3-9 years, objective signs of the disease increase in the majority of victims.
Prevention consists in the use of special respiratory protection equipment. At home, the solvent should be stored in a factory container outside the living room. It is forbidden to pour the substance into containers from under edible products. Children, the elderly and people with mental illnesses should not have access to toxic substances. If the solvent gets on the skin, you need to remove it with a rag, wipe the affected area with alcohol and rinse with soap and water. If you feel worse after working with the paintwork, you should call the ambulance or visit a doctor yourself.