First signs of methanol poisoning

Methanol poisoning is quite common in modern medical practice. It is a very dangerous substance that acts quite quickly and leads to severe consequences, disability and even death. The danger is that this substance is very similar in appearance to ethyl alcohol. Most cases of poisoning are associated with the fact that a person drinks this substance, confusing it with ethyl alcohol. Moreover, many counterfeit alcoholic beverages contain methanol instead of ethanol.

In addition to alcohol products, methanol is used in production and research. Therefore, cases of industrial and professional poisoning are common. In most cases, professional poisoning occurs when inhaling vapors and is chronic. Poisoning is caused by the production of toxic substances and oxygen deficiency. A distinctive feature of methanol is that it is quickly absorbed and slowly excreted from the body.

Statistics

About 5% of methanol poisonings are fatal. In 35% of cases, there is a sharp impairment or complete loss of vision. Renal and hepatic impairments are observed in 29% of cases. Oxygen starvation of tissues and cells is observed in 78% of cases. The cause of poisoning in 85% is the ingestion of methanol instead of ethanol, which occurs as a result of drinking low-quality drinks. Chronic poisoning occurs in 19% of cases, most often among chronic alcoholics. Professional ethanol poisoning when working with it occurs in 9% of cases.

Causes of Methanol Poisoning

The main cause of poisoning is the ingestion of methanol, since it is very similar to ethyl alcohol, and it is confused when drinking alcohol. Many people drink drinks containing methanol without even knowing it, since methanol often does not differ from ethanol in taste or smell. The cause of poisoning is the purchase of cheap and counterfeit alcoholic beverages, drinking alcohol of unknown origin in unfamiliar places. The number of poisonings especially increases on holidays.

There are also cases of chronic poisoning. Basically, such poisoning occurs when working with methanol at enterprises, factories, and in production. Poisoning often occurs in laboratory conditions, especially if the work is carried out in closed rooms, with a non-working exhaust hood. Poisoning often occurs during research in testing shops, research centers and institutes, in pharmaceutical companies.

Poisoning also often occurs when using various solvents during construction and repair work, and even when washing windows inside a car with special solvents. In this case, methanol evaporates well and poisoning occurs with its vapors, which intensively penetrate the skin and respiratory tract. Poisoning often occurs against the background of alcohol abuse, or in a state of drug intoxication. Some use it for the purpose of committing suicide.

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Risk factors

Workers involved in construction and repair, people working in factories, plants, and laboratories are at risk of poisoning.

Also at risk are people who abuse alcohol: who drink in large quantities, over a long period of time. Also at risk are people who drink cheap and low-quality types of alcohol, mixtures, surrogates, counterfeits.

Pathogenesis

The pathogenesis is based on the ability of the poison to be quickly absorbed through the respiratory tract, skin, and mucous membranes of the digestive tract. It primarily affects the nervous system and blood vessels. The oxygen saturation of the blood decreases sharply, the amount of carbon dioxide increases. As a result, hypoxia and hypercapnia develop. Oxygen starvation progresses quite quickly, resulting in acidosis, changes in blood acidity, which leads to collapse.

The danger is also that methanol in the blood undergoes chemical reactions, during which formic acid and formaldehyde are formed, which are dangerous substances that provoke severe poisoning and changes in the main biochemical indicators. In addition, vision is sharply impaired, the optic nerve is damaged, and the retina is damaged. The mechanism of these injuries consists in the disruption of oxidative phosphorylation processes, and glycolysis processes are also disrupted, resulting in a sharp shortage of ATP, which is one of the main substances necessary for the normal functioning of the body. Failure to provide timely assistance can lead to complete loss of vision.

Damage to the mucous membranes also occurs. Normal cellular metabolism is disrupted in the cells, and irritation of the mucous membranes occurs. Methanol is excreted by the lungs and kidneys. At the same time, approximately 10% of the substance is excreted unchanged. Also, the mechanism of action is that it blocks the action of alcohol dehydrogenase, which should break down and neutralize the action of toxic substances. As a result, not only methanol poisoning and its metabolic products occur, but also autointoxication.

Symptoms of Methanol Poisoning

The severity of the symptoms of poisoning directly depends on the amount of alcohol that a person has consumed. In this case, a sharp headache develops, dizziness, nausea, and vomiting appear. When swallowing, pain and burning often occur, which intensify as the food bolus passes through the esophagus. Nausea gradually intensifies, profuse vomiting appears, sometimes with blood impurities. A distinctive feature of methanol poisoning is the appearance of muscle pain, as well as a feeling of pressure and pain in the joints. In severe poisoning, which is accompanied by damage to the digestive tract,bleeding develops. The source of bleeding is the esophagus, stomach, intestines. This is most often observed against the background of ulcers, small erosions.

The patient's pupils dilate, there may be bouts of euphoria, a feeling of intoxication, and an inability to control their movements. Confusion also develops, speech and coordination of movements are impaired. Gradually, the person loses sensitivity, perception is impaired, and visual acuity decreases. The person loses coordination, image clarity and clarity of perception are impaired. Many develop photophobia and lacrimation.

Methanol causes severe hyperemia, swelling, therefore inflammation and swelling of the mucous membrane of the throat, trachea, nasal cavity often occurs, and lymph nodes become inflamed. There is a risk of respiratory arrest as a result of swelling, especially in people with respiratory problems and a tendency to allergic reactions.

Also, a symptom of late and severe poisoning is a disruption of the normal functioning of the heart and circulatory system. Blood pressure may increase or decrease sharply, the pulse may quicken or slow down. In this state, a person may lose consciousness or fall into a comatose state. In this case, the skin turns blue, the mucous membranes swell sharply, and convulsions appear.

How long does it take for the first signs of methanol poisoning to appear?

Poisoning may manifest itself several hours after methanol enters the body, or several days after consumption. Everything depends on the dosage and the method of ingestion.

The first signs include nausea, vomiting, and dyspeptic disorders. A feeling of intoxication and euphoria appears. The person begins to feel dizzy and photophobia appears. In most cases, the person does not feel poisoned, but associates these symptoms with alcohol abuse, and believes that they simply “had too much to drink.” It is easier to notice early symptoms from the outside: the person’s pupils become sharply dilated. At the same time, the gaze does not react to light, breathing becomes frequent and shallow. A headache appears, and pain gradually joins in throughout the body, especially in the muscles and joints.

An early sign of chronic poisoning is considered to be a gradual decrease in vision, impaired color vision, reddening of the eyes and the appearance of a pronounced vascular pattern on the eye. The reaction to light also decreases. The number of platelets in the blood decreases and the cholesterol level increases. According to subjective signs, a person feels a decrease in performance and increased fatigue, as well as an acute headache in the first half of the day.

Methanol vapor poisoning

Occurs as a result of prolonged exposure to methanol on the body, or as a result of a single inhalation of a large amount of vapor. Most often observed in employees who work with methanol. Signs include sudden visual impairment, weakness, headache, stinging eyes, dryness and burning of the mucous membranes. Narrowing of the pupils and redness of the eyes occur. Consciousness is impaired: poisoning is often accompanied by euphoria and psychomotor agitation, against which disorientation develops, speech and coordination of movements are impaired.

Chronic intoxication is often accompanied by weakness, decreased endurance and resistance of the body, and a sharp deterioration in well-being. Vision is sharply reduced, and color perception is impaired.

Consequences and complications

Poisoning is dangerous primarily because it causes oxygen starvation (hypoxia). Against this background, the carbon dioxide content increases sharply and the oxygen content decreases. This leads to the fact that normal metabolic processes are disrupted, tissues and organs suffer from a lack of oxygen. Another danger is that methanol promotes the formation of toxic products such as formaldehyde and formic acid, which have an additional toxic effect on the body.

No less dangerous are severe damage to the cardiovascular and respiratory systems, renal and hepatic failure. Also, the functions and composition of the blood are disrupted, in particular, the number of platelets decreases, which entails a violation of blood clotting. The risk of bleeding increases. The risk is especially high for a person suffering from an ulcer. Methanol has an irritating effect on the mucous membranes, disrupting their integrity and permeability.

Dangerous consequences of poisoning include damage to the nervous system. Chronic poisoning is dangerous because anemia, hypoxia, and red blood cell breakdown can develop.

Metabolic processes, water-salt, acid-base balance are disrupted. As a result, alkaline acidosis develops, coma and brain damage may develop. Poisoning may end in death.

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Can methanol poisoning be fatal?

Methanol poisoning is often fatal, especially if first aid is not provided promptly. Death often occurs as a result of oxygen starvation, kidney and liver damage, disruption of normal blood circulation and vascular conditions.

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Poisoning can be diagnosed based on the characteristic clinical picture. Usually, poisoning is diagnosed by the ambulance doctor who provides first aid. The person's heart rate increases, they feel sharp dizziness, and they lose consciousness. Vomiting and convulsions may join in. The pupils are dilated and do not react to light. To clarify the diagnosis, laboratory tests and instrumental studies are prescribed. Particular attention is paid to assessing the condition and number of red blood cells, since they are the ones that suffer first.

Tests

The main tests that show the overall picture of changes occurring in the body are clinical tests: urine, blood, feces, methanol analysis. Biochemical analysis can provide more detailed information.

The clinical blood test reveals anemia and thrombocytopenia. Also, a change in the number of leukocytes is detected in a wide range: from several hundred to hundreds of thousands in one µl. In this case, cellular forms with normal and reduced - leukopenic and subleukemic numbers of leukocytes predominate.

The main diagnostic criterion is the presence in the peripheral blood of the youngest (blast) hematopoietic cells, which are identified in a light microscope when stained with the Romanovsky-Giemsa method by the specific delicate mesh structure of the nucleus, which almost always contains one or more nucleoli. Blast cells predominate in the leukocyte formula. Mature granulocytes are detected as single rod-shaped and segmented neutrophilic granulocytes.

Mature granulocytes are practically not detected in the intermediate form, which reflects a failure in hematopoiesis. There is a sharp decrease in the number of erythrocytes. Basophilic granularity of erythrocytes is manifested when studying their morphology. In this case, erythrocytes acquire the form of blue grains. As for leukocytes, relative leukocytosis is noted, in which the number of leukocytes in the blood decreases sharply. In the blood against the background of intoxication, an increase in the number of neutrophils, a decrease in the number of eosinophils, monocytes is detected, ESR - erythrocyte sedimentation rate increases. The level of platelets also drops sharply, which reduces the blood's ability to clot. As a result, a tendency to bleeding develops.

Urine analysis allows to assess the stage and severity of damage to the main functional systems. Intoxication is always noticeable by the appearance of additional salts and formations in the urine ( oxalates, salicylates, bilirubin ). It is also possible to assess the condition of the kidneys, the degree of their damage (important, since methanol has a nephrotoxic effect). A large amount of protein, leukocytes in the urine indicate the development of an acute inflammatory process. A bad sign is the appearance of blood in the urine, which indicates severe degenerative changes in the kidneys and liver, as well as a significant decrease in platelets in the blood, which led to bleeding.

By examining feces, it is possible to obtain a clinical picture of pathological processes occurring in the gastrointestinal tract, liver, which also suffer from the effects of methanol. The main diagnostic criterion is the detection of occult blood in feces. Sometimes blood is simply detected during defecation, without additional studies. This symptom may indicate the development of necrotic, degenerative processes in the intestines, stomach.

In order to accurately determine the active substance that has a toxic effect on the body and that caused the intoxication, a toxicological study is carried out. If necessary, additional biochemical research methods are prescribed.

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Instrumental diagnostics

Instrumental diagnostics is rarely used, mainly at the recovery stage, after first aid has been provided and the necessary basic treatment has been carried out. It is necessary when signs of damage to internal organs appear, with various complications. Thus, poisoning is often accompanied by damage to the digestive tract, since it is the first to come into contact with the toxic substance.

Gastroscopy may be required if there is a suspicion of an esophageal burn, inflammatory diseases in the esophagus and stomach. For this, the patient swallows a special instrument - a gastroscope, which allows, with the help of a camera located at the end, to examine the walls and mucous membranes of the upper digestive tract. This makes it possible to identify inflammatory processes, tumors, especially in the early stages of their formation. The advantage of this procedure is that it can develop from diagnostic into therapeutic at any time. For example, if bleeding areas or severe damage to the mucous membrane are detected, small areas are removed, vessels are cauterized. During the procedure, biological material can be taken for further histological examination if there is a suspicion of an oncological process or degeneration of the mucous membrane.

Ultrasound is also often used to track the main processes occurring in the body in dynamics. This is an excellent addition to gastroscopy, which allows you to examine the digestive tract from a different angle. It allows you to get a general picture, study the topography of the organs, their anatomical and morphological features. Also, with the help of ultrasound, you can visualize many processes. These methods are very informative in combination, since they allow you to comprehensively assess the pathology, and even find out its causes.

The most basic method is magnetic resonance imaging, but it is used as a last resort, mainly when it is impossible to establish an accurate diagnosis using the two previous methods. It allows you to examine both soft tissues and the skeletal system. In addition, processes can be examined dynamically. This is one of the methods of early diagnostics, which allows you to visualize pathological processes at an early stage, and take the necessary measures in a timely manner.

It is used to accurately identify the cause of the development of a pathological process in the body and to determine the substance that has a toxic effect on the body. The main method is toxicological research, as well as a number of other biochemical methods.

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Antidote for methanol poisoning

If methanol poisoning occurs, an antidote must be administered. Ethyl alcohol acts as an antidote. If other measures cannot be taken, it is simply drunk. If possible, it is better to administer intravenously a mixture of 5% ethyl alcohol with 5% glucose. Administer 200 ml every 4 hours for 72 days. In this case, it is necessary to monitor the amount of alcohol in the blood.

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Prevention

For prevention, first of all, it is necessary to instill and observe the culture of alcohol consumption, since the main cause of poisoning is the use of low-quality alcohol, which contains methanol instead of ethanol. These are various counterfeit products purchased in dubious places, without a license. You cannot mix different types of alcohol, drink very cheap drinks. You should also carefully store methanol at home, if such a need arises. The bottle is labeled and placed away from food products, hidden from children. When working with methanol in industrial and laboratory conditions, it is necessary to strictly observe safety precautions.

Forecast

If first aid is provided promptly, the poison is neutralized, and removed from the body, methanol poisoning may have a favorable outcome. After emergency aid is provided, further supportive and restorative treatment is required. If first aid is not provided and an ambulance is not called, the consequences may be extremely unfavorable, even fatal.

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