It is an antidote for organophosphate poisoning. Poisoning with organophosphorus compounds (OPCs). Pathogenesis (mechanism of development) of phos. poisoning. Signs (clinic) of poisoning with organophosphorus compounds. Phosphorus compounds in everyday life

Poisoning with organophosphorus compounds is often recorded, since the substances are widely distributed in everyday life and, in the absence of safety measures, easily lead to intoxication. In case of direct contact, it is necessary to call a medical team and, if possible, provide first aid. In this case, the risks of health complications will be significantly reduced.

Phosphorus compounds in everyday life

They are complex chemicals that are used not only in production, but also at home and in veterinary medicine. Currently, FOS is used:

The toxic properties of organophosphorus substances can be judged by army developments. Based on the chemical element, poisons such as Soman, Zorin, and V-gases have been developed.

FOS can be solid, volatile, liquid. Basically they have a specific garlic-kerosene aroma, dissolve well in fatty media and poorly in H2O. In this case, the toxicity of aqueous liquid when heated to 35° C increases 35 times.

Almost every day a person encounters such connections. The following organophosphorus agents are considered the most dangerous:

metaphos;
DCVF;
thiophos;
heterophos;
phthalophos;
methyl mercaptophos;
coral;
chlorophos;
dichlorvos;
karbofos.

In agriculture they use:

Dimethoate Plants are sprayed that become poisonous to sucking insects.
Fenitrothion. Used in industry to protect citrus and fruit crops. Also in demand for processing vegetable seeds.
Diazinon. Recommended for surface application and soil application. Over the course of several days, the roots absorb the substance, which saturates the entire bush.

The compositions of these phosphorus-containing drugs contain malathion, diazinon and pirimiphosmethyl, which are extremely dangerous for humans.

Routes of poisoning by FOS

Intoxication occurs in 3 ways:

Orally. It develops as a result of the ingestion of phosphates, phosphides, and phosphines through the gastrointestinal tract with water containing toxins, poorly washed fruits, and unsterilized milk.
Inhalation. The cause is inhalation of vapors.
Percutaneously. Direct contact with skin.

Penetrating into the body, phosphorus compounds block cholinesterase (AChE). An enzyme is formed that is highly resistant to the hydrolysis process. It destroys acetylcholine and gradually accumulates, leading to the development of a clinical picture. Effect classification:

At the slightest symptoms of poisoning with organophosphorus compounds, it is necessary to urgently call emergency help; it is advisable to show doctors the substance that caused it.

Signs of FOS poisoning

After contact, organic phosphorus compounds are absorbed into the blood. In this case, they can penetrate through the mucous membranes of the mouth, stomach and intestines, lungs, and skin. The processes are characterized by a cyclical feature. The chemical is transformed, creating new toxic substances, and repeated interaction with drugs is not required. Both adults and children are at risk from such chronic intoxication. According to statistics, relapses develop in approximately 10% of patients.

Stages of FOS poisoning

Phosphorus damage has a general clinical picture, which practically does not depend on the type of agent. Symptoms develop in 3 phases:

Excitation.

Already 15 minutes after intoxication with organophosphorus compounds, initial signs appear:

cephalgia;
attacks of nausea;
gagging;
abdominal pain;
constriction of the pupils;
increased salivation;
profuse sweat;
blood pressure jump;
increased heart rate.

It is advisable to provide first aid to the victim already at this stage.

2. Hyperkinesis and convulsions.

If no measures are taken, after a few hours, a person experiences the following symptoms of poisoning with organophosphorus compounds:

general malaise;
vision problems;
difficulty breathing;
profuse sweat;
pain when urinating and bowel movements;
muscle twitching.

Stupor is noted as coma progresses. In this case, the pupils do not respond to light, the tone of the skeletal muscles is increased, chest movements are limited, and blood pressure rises to critical levels. The spasms gradually move to the muscle tissues of the neck, synergists of the legs, and forearms. Collapse is likely.

At this stage, there are no tendon reflexes, bradycardia and a drop in blood pressure appear. Greater risk of death if left untreated.

Long-term consequences of poisoning with organophosphorus compounds can appear even after several years.

Symptoms of possible complications resulting from intoxication

Defeat of FOS negatively affects almost all groups of internal organs:

The cardiovascular system suffers. The pulse rate reaches 120–130 beats. Arterial hypertension is observed, after which collapse usually develops.
Excessive production of acetylcholine provokes profuse secretion of sweat and saliva. Miosis appears - a sharp constriction of the pupils, which is accompanied by loss of the light reflex.
Initial convulsions when cholinesterase is inhibited lead to paralysis of the striated and respiratory muscles. Muscle tone disappears, nervous activity is disrupted.

The comatose state can last up to 6 days.

Diagnosis of intoxication

The examination includes the study of indirect and direct signs of poisoning with organophosphorus compounds. For pathogenesis, it is advisable to have an idea of the location of the lesion and to warn doctors about the presence of a characteristic odor.

A biochemical study of blood composition helps confirm the presence of FOS. In addition, pay attention to the speed of the reaction - the clinic appears very quickly, which makes it possible to separate it from the manifestations of intoxication with chlorine, zinc, hydrogen sulfide, ammonia and other chemicals.

First aid

As soon as the victim shows signs of organophosphate damage, several steps must be followed in succession.

Algorithm of pre-medical actions:

In case of oral poisoning, it is recommended to rinse the stomach using such agents as magnesium sulfate, petroleum jelly, a universal antidote for poisoning - activated carbon, which is taken 1 tablet for every 10 kg of weight.
If vapors penetrate into the pulmonary system, the person is taken out into fresh air and the gastrointestinal tract is also cleaned. An antidote and laxative are indicated.
If the skin comes into contact with a substance that can poison, use a soap solution, 20% soda, or chloramine. When direct phosphorus damage is observed, the damaged area must remain moist, otherwise ignition is possible.
If necessary, resort to indirect massage of the heart muscle.

The patient is quickly transported by ambulance to the hospital, where further therapy will take place.

Treatment

People exposed to organophosphate toxic substances are sent to the intensive care unit.

The program includes diagnostics, on the basis of which an optimal scheme is developed:

In case of acute intoxication, it is recommended to administer 2–3 ml of Atropine 0.1% intravenously or subcutaneously. Injections are repeated every 15 minutes until symptoms such as sweating and saliva disappear. Dilated pupils and dry mouth are evidence indicating discontinuation of this treatment method. Sometimes the daily dosage reaches 50–70 ml. But usually 5–10 ml is enough to normalize the condition.
Antidotes are used to neutralize the poison - Dipiroxime 15%, 1 ml, Isonitrozine 40%, 2 ml. With their help, they eliminate cramps and restore breathing.
To reduce the absorption of organophosphorus compounds, the stomach is cleansed again with activated carbon.
For persistent high blood pressure, use 3% Dibazol, 25% magnesium sulfate. Drip administration of 2.5% Aminosine helps. But this drug must be used carefully, as there are risks of collapse.

Doctors need to select a specific antidote that will eliminate the severe symptoms of poisoning as soon as possible. Pharmacology offers an extensive list of drugs that can be included in the treatment program:

cholinesterase reactivators;
Pentafen;
Amizil;
Dipiroxime;
Isonitrosine;
Tropacin.

The following activities are carried out:

If necessary, connect to an artificial respiration apparatus.
Antibiotics are prescribed to exclude infection.
To prevent blood thickening, anticoagulants are used.

Antidote therapy is carried out depending on the degree of poisoning. Most effective in the first 6 hours. For damage caused by certain compounds, it is not required. For example, if avenin or methylacetophos is detected in the body, the patient will be treated symptomatically, using drugs that eliminate common toxic manifestations.

Late use of antagonists is dangerous, since the compounds have a negative effect on the liver, heart and provoke re-intoxication.

Prevention

To prevent both acute and chronic poisoning by organophosphorus compounds, it is necessary to adhere to safety recommendations:

To prevent pathology from becoming an occupational disease, work using protective equipment.
Limit children's access to household products containing the chemical.
Promptly dispose of empty containers and expired substances.
In case of contact with skin, immediately remove clothing, rinse areas thoroughly, and trim nails and hair.

If prevention was not followed and you managed to poison yourself with phosphorus, phosgene, tetrachloroethane, organochlorine acid or other substances, you should urgently call doctors - symptoms appear quickly, often severe. Timely hospitalization will reduce the existing risks of complications, and possibly save the life of a seriously injured person.

Organophosphate chemical compounds are found in teeth, bones, and all kinds of cells in the human body. It is phosphorus that makes the teeth and skeletal system strong and resistant to various types of stress. Without organophosphorus compounds (abbreviated FOS or FOV), the nervous system simply could not function properly. However, a large number of them can negatively affect human health and first aid will be required in case of poisoning with these toxic elements.

Features of FOS

Organic phosphorus compounds in their molecular composition contain many elements: phosphines (self-igniting, characterized by chemical instability, considered the strongest poisons; metaphos; karbophos; butifos; methyl-nitrophos. OPCs include: phosphamide; chlorophos; octamethyl; thiophos.

A small concentration of FOS can suppress enzyme systems in the body of dogs and cats, so these compounds are often used as medicines for the treatment of malignant tumors and glaucoma in animals. Scientists have discovered that organophosphorus compounds have a mutagenic effect on cells.

Symptoms of OPA poisoning primarily depend on the method of entry of the chemical into the body, the category of the toxic chemical and the degree of toxicity. Due to the fact that these elements inhibit enzymes, nervous system disorders and problems with the functioning of internal organs may occur.

Areas of application of organophosphorus compounds

Organophosphorus elements were also used as poison in wartime. FOS is often used in traditional medicine - the compounds are included in ophthalmic drops and medicines that help normalize the functioning of the gastrointestinal tract. Using a chemical, head lice can be cured.

FOS, in its consistency, comes in both solid and liquid form; they have a pronounced garlic-kerosene smell. The compounds react well with fats and dissolve in them, but react very poorly with water. For humans, toxic emissions are poisonous and dangerous. Chemical elements can enter the human body through the upper respiratory tract, skin and digestive system. You can be poisoned by organic phosphorus compounds through contaminated water, food, clothing, and household items.

Symptoms of OPA poisoning

When ingested, organic phosphorus compounds are instantly absorbed from the mouth, stomach, and intestines and end up in the blood plasma. Poisoning with elements is dangerous for humans due to serious complications: about fifty percent of the compounds are transformed in the body and become more toxic. 7-10% of people who have been poisoned with FOS at least once often experience relapses. Repeated contact with phosphamide, thiophos or butifos is not required for relapse to occur. The reappearance of poisoning is called chronic phosphorus intoxication.

Doctors distinguish three stages of poisoning, which have their own signs and symptoms: the first is the acute period (lasts from 1 to 3 days), the second - complications appear (lasts from 4 days to 2 weeks), the third - long-term consequences arise (lasts from 1 month up to 3 years). During the first stage of poisoning, various body systems are excited, the peripheral and central nervous systems are affected.

Acute symptoms of poisoning with organophosphorus substances include:

partial or complete loss of vision;
increased sweating and salivation;
disruption of the respiratory system, paralysis of the respiratory muscles;
decreased heart rate, bradycardia or bronchospasm occurs;

If a large amount of toxic substances enters the body, the victim may lose consciousness and even fall into a coma. Also, during the acute period of poisoning, nerve cells are affected, shortness of breath, a decrease or increase in body temperature, fluctuations in blood pressure, convulsions and agitation are observed.

If complications occur, the symptoms practically go away, but other signs appear: pneumonia; cyanosis of the skin; toxic hepatitis; swelling in the brain; complete absence of reflexes; kidney damage; hypotension. The last stage is the most dangerous, since the muscular and nervous systems, liver, kidneys and other internal organs are almost irrevocably affected.

The essence of diagnosis for poisoning with organophosphorus compounds

The diagnosis is made on the basis of symptoms from the nervous system: loss of vision; disorders of the gastrointestinal tract; seizures; tremor; increased salivation. In order to diagnose the degree of poisoning and the level of toxic effects provided, it is necessary to examine in detail the place where the injured person was at that moment.

If you smell a garlic-kerosene smell from clothes and household items, you can talk about the presence of phosphorus compounds in the room. The doctor will be able to establish an accurate diagnosis after receiving the results of a biochemical analysis of blood plasma, which the patient must immediately submit.

During an acute period of poisoning, symptoms may occur immediately or after some period of time. If a person has a fulminant form of poisoning, he will begin to have convulsions half an hour after contact with FOV, otherwise, tremors will occur after 3-5 days.

First aid

In case of FOS poisoning, the person should be taken out of the room into fresh air so that toxic substances do not affect the body and are not inhaled along with oxygen. It is recommended to remove the victim’s clothes and wrap them in a warm blanket. If there are clean clothes, it is advisable to change into them.

People around can help the victim by performing a gastric lavage procedure. In case of poisoning, you need to constantly monitor the amount of saliva in a person. To alleviate the patient's condition, a saline laxative, petroleum jelly, activated charcoal, or sodium sulfate should be given.

People around you can provide first aid in case of poisoning with organophosphorus substances by washing the affected areas of the epidermis. Damaged skin should be washed with clean water, laundry soap and a two percent soda solution. It is recommended to treat the skin with Chlorhexidine or Chloramine.

The essence of first aid for poisoning with organophosphorus compounds is the intravenous administration of a solution of “Atropine”. Injections should be administered 2-3 times a day until bronchorrhea, increased salivation and excessive sweating stop. The appearance of dryness in the oral cavity is considered a positive result of therapy. A single dose varies from 0.5 to 2 milliliters of solution.

It is recommended to inject other drugs with anticholinergic effects together with Atropine: Aprofen, Amizil or Tropatsin. “Atropine” must be administered until the symptoms disappear completely, otherwise a relapse is possible.

In combination with Atropine, in the first 24 hours you need to inject 1 milliliter of a fifteen percent solution of Dipiroxime intravenously or intramuscularly every 2 hours.

You should also pay attention to symptomatic treatment. If the victim's blood pressure has increased, it is recommended to administer 1.5 milliliters of one percent Diabazol. If a person has severe hypertension and tremor, one should inject “Sodium hydroxybutyrate” three times a day, 100 milligrams per 1 kilogram of weight.

In cases of paralysis of the respiratory muscles, artificial ventilation is indicated. In this case, Hydrocortisone is injected intramuscularly at a dose of 5 milligrams per 1 kilogram of body weight once a day. In case of blockade and low activity of enzymes in the body, blood replacement surgery is recommended. This serious procedure is carried out 3-4 days after poisoning.

Preventive measures

In order not to be poisoned by organophosphorus compounds, you should not neglect safety rules. When working with organic phosphorus substances, you need to wear special protective clothing to prevent toxic elements from getting on your skin.

As a preventive measure, young children should be kept away from containers containing FOV. The container must be disposed of in a timely manner. If, nevertheless, a toxic chemical compound gets on your shirt or pants, they must be removed immediately. If organic phosphorus substances get on the nail plates and hair, the following measures should be taken: hands should be washed with soap and water and nails should be cut, and it is advisable to cut off the affected hair. These manipulations are carried out to ensure that chemical elements do not enter the body through hair, nails and epidermis.

First aid for FOS poisoning will, of course, help the injured person, but you should definitely call an ambulance to hospitalize the patient. Timely provision of first aid by surrounding people and the prompt arrival of medical workers can save a person’s life and minimize the likelihood of complications and serious consequences.

FOS are compounds based on phosphorus. This is, of course, an important element for human health, taking part in the structure of bone tissue and nourishing the nervous system.

But only natural phosphorus in food, in moderation, is beneficial. Artificial phosphorus-based compounds are unsafe. What happens if they enter the body in excess?

We call artificial phosphorus-containing substances FOS. Sometimes they are designated under another abbreviation FOV.

Substances in which we can see these compounds are extremely dangerous. This:

toxic substances, including the notorious sarin;
fertilizers;
pest control products;
medical preparations for various purposes.

As you can see, phosphorus, which is strongly recommended to be obtained with fish, becomes deadly once it falls into the hands of scientists.

There are many phosphorus-based compounds; they can exist in one of three states. Their characteristic feature is a smell reminiscent of kerosene.

Phosphorus-based substances enter through one of three main routes of penetration of poisons: through the air, through the skin, and through contaminated food. As a rule, these are food products treated with fertilizers, dirty water, into which residues of phosphorus-based fertilizers penetrate.

Symptoms of FOS poisoning

In the body, phosphorus-based substances are quickly absorbed into the blood. With approximately every second poisoning, phosphorus is converted into a more dangerous poison.

A feature of phosphorus is the cyclical nature of poisoning. For this reason, relapses may occur in case of FOS poisoning in every tenth person. In this case, we can state chronic poisoning of the body.

Damage to the nervous system

The first thing that FOS affects is the nervous system. The impact has three stages. The first stage takes up to 3 days. The second lasts up to 2 weeks. The third period lasts up to 3 years.

Symptoms first stage:

blurred vision;
salivation;
pain in the intestinal area;
diarrhea;
general weakness;
respiratory dysfunction;
convulsions;
sudden changes in pressure and body temperature;

If a large dose of a substance enters the body, a disorder of consciousness, coma, and respiratory arrest occurs.

Second stage

At the next stage, the above signs become somewhat weaker. But it is added to them:

skin cyanosis appears;
impaired reflexes;
decrease in pressure;
cerebral edema.

On third stage Damage to internal organs, such as the liver, kidneys, appears, and the central nervous system suffers.

How to determine FOS poisoning?

An accurate diagnosis can only be made using a blood test.

A garlic smell may indicate poisoning. In addition, the following signs should alert you:

convulsions;
muscle twitching;
visual impairment;
stomach disorders.

If the victim received a high dose of the substance, symptoms appear within an hour.

First aid

Treatment of poisoning

After identifying FOS poisoning, an ambulance is immediately called. The victim is given first aid, after which the patient undergoes treatment in a hospital. The patient is given an antidote.

Preventive measures

To avoid poisoning, it is necessary to work in special clothing and avoid contact of the substance with the skin.
Keep hazardous products out of the reach of children.
If the substance gets on clothing, it must be removed. If it's for hair, the hair needs to be cut.

Organophosphorus compounds (OP) are highly toxic substances that are extremely dangerous for the human body. Some OPCs were developed as nerve agents (Sarin was even used by terrorists). Organophosphates and carbamates are commonly used as insecticides. OPC poisoning is accompanied by severe intoxication and requires immediate medical attention at a clinic, as it poses a mortal threat to humans.

Mechanism of poisoning

Poisoning with organophosphorus compounds most often occurs when using chemicals intended for treating premises against rodents and insects and protecting crops from pests. Intoxication is less commonly observed due to the use of FOS as chemical warfare agents (during military operations) and with the improper use of insectoacaricidal agents for animals and medications that contain organophosphorus compounds.

The following ways of penetration of the toxin into the body are distinguished:

eating unpeeled vegetables and fruits treated with phosphorus-based insecticides;
drinking water that contains toxic compounds;
inhalation of FOS vapors when treating plants and animals, premises;
consumption of milk from animals fed on grass and feed poisoned with a toxic substance.

FOS can enter the human body orally, through the respiratory tract and skin. Receiving any dose of poison quickly leads to disruption of the production of cholinesterase, the most important enzyme responsible for nervous activity. If cholinesterase activity decreases, this provokes the release of acetylcholine and excessive long-term excitation of M- and H-cholinergic receptors. Such changes entail disturbances in the functioning of vital systems (cardiovascular, nervous, respiratory, visual, digestive).

Signs and symptoms of OP poisoning

Symptoms of OP poisoning depend on the stage of intoxication. There are 3 degrees of poisoning with toxic phosphorus-containing compounds:

Excitation.
Stage of convulsions and hyperkinesis.
Paralysis.

The first phase, which develops approximately 20 minutes after the toxin enters the body, is characterized by the following symptoms:

headache;
dizziness;
excessive sweating;
lacrimation;
muscle weakness;
nausea, vomiting;
decreased visual acuity;
abdominal pain, diarrhea;
bradycardia (decreased heart rate).

At stage 2, the victim experiences hyperkinesis (frequent involuntary twitching of the muscles of the body and face), convulsions, a sharp increase and decrease in blood pressure, confusion and lethargy, cyanosis of the skin. Patients have no reaction of the pupils to bright light, the sphincters of the bladder and anus relax, and toxic damage to the liver, kidneys, lungs, stomach and intestines develops. At this stage, the victim may fall into a coma.

Organophosphate poisoning of the 3rd degree is accompanied by a complete disruption of nervous activity, which leads to a weakening of all reflexes. The victim experiences paralysis of the body muscles, a strong decrease or increase in heart rate (less than 30 or more than 120 beats per minute), and depression of the functions of the respiratory center. If breathing stops, death occurs. This can happen 3–9 hours after toxic compounds enter the human body.

Possible consequences

Organophosphorus compounds tend to be transformed in the human body into more toxic substances, which lead to disruption of vital systems and provoke the development of dangerous pathologies.

In case of poisoning of the 2nd and 3rd degree of severity, paralysis of the entire muscles of the body occurs, including the muscle tissue of the internal organs, which causes deviations in their work.

The victim may experience gastrointestinal diseases, pneumonia, bronchitis, nephropathy, hepatitis, and myocardial dystrophy. In the absence of timely medical care, the person falls into a coma and dies. Survivors often experience long-term effects of toxic poisoning. Problems may arise 2–3 years after intoxication. Such complications include polyneuritis, asthenovegetative syndrome, and inflammatory diseases of the spinal cord.

First aid for poisoning with organophosphorus compounds

In case of poisoning with organophosphate compounds, the victim must be removed from the poisoned area into fresh air. Contaminated clothing must be removed, skin and eyes should be treated using a 2% soda solution (1 tsp sodium bicarbonate per 2 cups of water). The stomach should be rinsed generously with warm water, after which it is recommended to give the poisoned person a saline laxative. At the same time as providing first aid to the victim, it is necessary to call an ambulance team.

The patient should receive the antidote as quickly as possible. In case of poisoning with organophosphorus compounds, intravenous or intramuscular administration of atropine sulfate, an M-cholinergic receptor blocker, is indicated. Additionally, it is necessary to use cholinesterase reactivators - drugs that restore enzyme activity and reduce the severity of the toxic effect. Such drugs include trimedoxime bromide (Dipiroxime) and isonitrosine.

Treatment

In case of poisoning by toxic compounds, a person undergoes complex intensive therapy in a hospital setting. Treatment includes the following measures:

The use of atropine sulfate in combination with cholinesterase reactivators during the first 3–4 days after the development of intoxication.
Introduction of M- and N-anticholinergic drugs.
The use of drugs for symptomatic treatment aimed at normalizing the functions of internal organs, eliminating seizures, improving general condition (glucocorticosteroids, detoxification, anticonvulsants, vasodilators).
The use of antibiotics (for the prevention and treatment of the consequences of toxic damage to internal organs).

Extracorporeal detoxification methods - hemosorption, hemodialysis, hemofiltration - are effective in the early stages of poisoning.

If the victim experiences coma or respiratory arrest, resuscitation measures and the use of artificial ventilation are indicated.

Preventive actions

To avoid intoxication when using organophosphorus substances, it is necessary to follow a number of important rules:

When preparing solutions and processing premises or garden areas, it is necessary to use personal protective equipment: gloves, mask, shoes, suit.
Chemicals should be stored out of the reach of children and pets.
For 3–4 days after applying insecticides to the surface of a room or plant, it is necessary to exclude people and animals from the treated area.
After working with toxic substances, you should wash your hands with soap and water. It is necessary to especially carefully clean berries, vegetables and fruits collected from shrubs and trees treated with chemicals under running water.
Do not eat or smoke while using solutions.
It is best to treat agricultural land in cool weather, since the toxicity of ready-made phosphorus-containing solutions at a temperature of +35 ° C increases several times.

At enterprises using organophosphorus substances in production, worker health and safety standards must be strictly observed. At the first signs of intoxication, you should immediately seek help from specialists.

According to the toxicity of FOS there are:

potent (LD50<50 мг / кг),
highly toxic (LD50 from 51 to 200 mg/kg),
moderately toxic (LD50 from 201 to 1000 mg/kg),
and low toxicity (LD50 > 1000 mg/kg).

Organophosphorus compounds are crystalline substances or liquids. Most of them are highly soluble in fats and other solvents (xylene, toluene, acetone, chloroform), and have a specific kerosene-garlic odor. Only some of them are soluble in water, in particular chlorophos, methylacetophos, phosphakol. They are quite stable, but in an alkaline environment at high temperatures they hydrolyze within 24 hours. However, in an acidic environment, they can persist in soil for months.

The toxicity of aqueous solutions at a temperature of 35 ° C can increase tens of times per day. Organophosphorus substances enter the body mainly through the mouth, as well as through the respiratory tract and skin. Human intoxication occurs due to the use of contaminated water; consumption of vegetables and fruits after treating gardens and orchards with appropriate FOS, when spraying them on trees and premises, consumption of milk from cows that have consumed contaminated water and feed, etc.. These same properties and their high volatility determine the intensive intake of poison through the skin and respiratory tract ways.

Effect on the body

Absorption of FOS begins in the oral cavity, then continues in the stomach and intestines. Due to their high lipoidotropy, they soon appear in the blood through any of the indicated penetration routes, in all organs, including the brain. In the body, their toxicity increases sharply, since about 50% of them are biotransformed in the liver according to the type of lethal synthesis, that is, with the formation of very toxic metabolites.

They are excreted from the body by the kidneys, about 30% unchanged, and 20-25% by the respiratory tract.

The toxic effect is due to their anticholinesterase properties. By interacting with acetylcholinesterase, organophosphorus compounds form an inactive phosphorylated complex that is capable of catalyzing acetylcholine. As a result, the content of this mediator in the synaptic cleft of cholinergic synapses sharply increases, which leads to prolonged excitation of m and n-cholinergic receptors.

In addition, these compounds can reduce the activity of proteases, acid and alkaline phosphatases, phosphorylate some proteins, disrupt blood composition, block membrane ATPases and disrupt the permeability of myocardial cell membranes.

Stages of poisoning

There are two stages of acute poisoning with organophosphorus compounds:

first (cholinergic),
the second (non-cholinergic).

First stage manifested by the effects of significant stimulation of m and n-cholinergic receptors, i.e.:

miosis,
spasm of accommodation,
visual impairment,
salivation,
bronchorrhea,
increased peristalsis and intestinal spasm,
diarrhea,
bradycardia,
acute respiratory failure due to peripheral respiratory impairment (cholinomimetic effect).

In this case, psychomotor agitation, ataxia, shortness of breath, tremors, clonic-tonic convulsions, confusion, coma, paralysis of the respiratory center develop as a consequence of the central n-cholinomimetic effect.

In addition, as a result of excitation and subsequent paralysis of vital centers, nerve nodes and executive organs, there is first an increase and then a decrease in blood pressure, heart rhythm disorder, an increase and subsequent decrease in body temperature, signs of adrenal exhaustion, hyperglycemia, hypokalemia, and the appearance of edema lungs.

At the second stage of acute FOS poisoning the signs of the first stage begin to weaken somewhat, but signs of exotoxic shock appear:

cyanosis,
areflexia,
heart rhythm disturbance,
hypotension,
manifestations of acidosis,
cerebral edema,
convulsions.

Sometimes, on the 2-8th day, a relapse of poison intoxication occurs.

Death in the first stage of acute OP poisoning can occur at the height of convulsions due to overexcitation and paralysis of the respiratory center, and in the second - through fibrillation of the ventricles of the heart, sudden cardiac arrest or paralysis of the respiratory center. Acute heart failure can be the result of aspiration-obstruction, peripheral respiratory disorders or toxic pulmonary edema.

Clinical symptoms of FOS poisoning

During acute FOS poisoning, it is customary to distinguish 3 periods:

acute - 1-3 days;
complications - 4-14 days;
long-term consequences - up to 3 years.

Manifestations of acute poisoning are determined by the stage and severity of intoxication and complications (of course, at the second stage - in the form of pneumonia, toxic hepatitis, nephropathy, myocardial dystrophy, etc.), and long-term consequences - in the form of asthenovegetative syndrome, myeloradiculoneuritis, polyneuritis.

Based on the rate of increase in the manifestations of acute poisoning with organophosphorus compounds, lightning-fast and slow-flowing forms are distinguished (mild poisoning, moderate poisoning, severe, extremely severe).

In victims with a fulminant form of intoxication, convulsive syndrome develops within the first 30 minutes after the poison enters the body.

Victims with mild poisoning complain about:

dizziness,
headache,
Pain in the eyes,
photophobia,
"fog in the eyes"
sometimes psychomotor agitation or depression,
nausea,
vomit,
spasmodic pain in the abdomen,
diarrhea,
sometimes difficulty breathing,
feeling of tightness in the chest.

They have sweating, pale skin, salivation, in some - moderate bronchorrhea, moderate miosis, with impaired pupillary reactions to light, trembling of the eyelids and outstretched fingers. Tachycardia, slight hypertension. Frequent urination. Cholinesterase activity is reduced by 20-50%.

More severe manifestations are typical for moderate poisoning. Victims show signs of bronchospasm and central nervous system disorders:

psychomotor agitation,
hallucinations,
disorientation,
ataxia,
movement coordination disorders,
myofibrillation (tongue, face, legs, chest),
miosis,
spasm of accommodation and visual impairment.

From the cardiovascular system, bradycardia or tachycardia, respiratory hypertension - shortness of breath with difficulty in exhalation, noisy or Cheyne-Stokes breathing are noted; glands - salivation, bronchorrhea, sweating; in the lungs - dry and moist wheezing; in case of oral poisoning - nausea, vomiting, abdominal pain, diarrhea. Urination is involuntary. There are no convulsions. Cholinesterase activity is reduced by 51-70%.

For severe forms Slow acute poisonings, in addition to the indicated cholinomimetic manifestations, are characterized by convulsions and loss of consciousness, and later bronchospasm. Breathing becomes bubbling, and a significant amount of foamy secretion is noted. Fibrillation covers all muscles. During convulsions, consciousness is lost. Body temperature rises. The development of acute respiratory failure is very dangerous. Involuntary not only urination, but also defecation are possible. Cholinesterase activity drops by 71-80%.

Extremely severe acute poisoning with FOS characterized by the cessation of seizures, the appearance of paralysis and coma. Consciousness, like reflexes, is lost, cyanosis increases, and body temperature decreases. Breathing is arrhythmic, shallow, frequent. The heart rate increases, and paroxysmal ventricular tachycardia is possible. There is acute vascular insufficiency (collapse). Cholinesterase activity does not exceed 10% of normal.

Mortality at the toxic stage of FOS poisoning is quite high. Affected individuals die from sudden cardiac arrest or ventricular fibrillation, central paralysis, or from acute respiratory failure due to paralysis of the respiratory muscles.

Clinical manifestations of acute OP poisoning are largely determined by the routes by which the poison enters the body. When a lethal dose of poison is administered orally, signs of acute intoxication appear within 10-15 minutes, coma after 20-30 minutes, and death after 3-9 hours. In case of prolonged acute poisoning, death occurs on the 2-6th day.

With percutaneous penetration, the first signs appear later, sometimes even after 2-3 days. They can occur suddenly after mild symptoms, in the form of weakness, headache, muscle twitching, sweating at the site of contact of the poison with the skin.

Treatment of acute OP poisoning

When creating individual programs for providing emergency care to victims of acute OP poisoning, the efforts of medical personnel are directed, first of all, to eliminating the most dangerous manifestations of intoxication, in particular: the primary specific cardiotoxic effect (disorders of heart rhythm and conduction, acute heart failure, sudden cardiac arrest) , central respiratory paralysis, acute respiratory failure due to paralysis of the respiratory muscles.

The treatment program should include: a complex of intensive resuscitation measures and an active complex of specific and pathogenetic therapy. Of the resuscitation measures carried out at the scene of the incident, particularly important is gastric lavage (if the poison has entered the body orally), washing the eyes and washing it off the skin with plenty of water and soap or a 2% solution of sodium chloride, chloramine or ammonia. In case of acute inhalation poisoning, the victim should be removed from the contaminated room or area and the same measures should be taken. In the hospital they resort to forced diuresis or peritoneal dialysis.

Antidote atropine

Of the medications, atropine sulfate is of leading importance as a remedy that eliminates all manifestations of the cholinomimetic effect of the poison and thus provides specific protection for the victim. It is administered intravenously, intramuscularly or subcutaneously in the form of a 0.1% solution in doses determined by the severity of acute poisoning, and repeatedly and for a long time, preferably in combination with cholinesterase reactivators.

Intensive atropinization is carried out within an hour. To do this, the patient is injected with 2-4 ml of a 0.1% solution of atropine sulfate every 10-15 minutes, until characteristic signs of the action of this drug appear - a decrease in bronchorrhea, dry skin and oral mucosa, noticeable tachycardia, etc.

It is advisable to carry out this stage of treatment in accordance with the severity of the condition.

In particular, it is recommended that in case of mild FOS intoxication, 2-3 ml of this solution should be administered intravenously to victims; patients with moderate acute poisoning should be given 5 ml intravenously; 3 ml intramuscularly and 4 ml subcutaneously; and 10-14 ml intravenously for severe and extremely severe poisoning; intramuscularly and subcutaneously 3-5 ml.

Over the next 3-4 days, maintenance atropinization is carried out by repeated administration of a 0.1% solution of atropine sulfate in 30-50 ml or more per day.

In addition to this drug, it is advisable for patients, especially with severe acute poisoning, to administer such central and peripheral m and n-cholinergic drugs as aprofen and Arpenal (1 ml each). It is advisable to combine atropine treatment with the administration of cholinesterase reactivators: dipyroxime, dietixime. Thus, dipyroxime is administered intravenously or intramuscularly, 1 ml of a 15% solution 6-7 times during the first day, dietixime - 3-5 ml of a 10% solution intramuscularly.

At the same time, to prevent cardiac disorders, they resort to the administration of 5-10 ml of a 5% solution of unithiol, 300 mg of tocopherol acetate and 60 mg of prednisolone. For arrhythmia, antiarrhythmic drugs are indicated.

If breathing stops or suddenly weakens, you should resort to artificial ventilation. If convulsions are not relieved by specific therapy, use magnesium sulfate intramuscularly 10 ml of a 25% solution, sodium hydroxybutyrate intravenously 5-120 mg/kg in 20 ml of a 5% glucose solution. An effective combination of aminazine (2.5% solution), diphenhydramine (2% solution) and promedol (2% solution) - 2 ml of each.

Vascular agents are also used, and antibiotics are used to prevent pneumonia.

After emergency care, all injured persons must be hospitalized in intensive care units of hospitals that have artificial kidney devices, or in poison control centers.