Endotracheal Anesthesia: What is it, testimony, preparations

Today, no one is surprised by this method of treatment, as a surgical intervention. And yet several centuries ago the operation was equated to death: most patients died of pain shock or sepsis. For a long time, the introduction of a person into a surgical sleep remained the most difficult task of medicine. With the study of chemistry, the process went faster. Better mixtures and preparations for anesthesia were created, which, in addition, are now carried out in various ways. One of them is endotracheal anesthesia. What it is? How is it used and in what cases is it necessary? These and many other questions will be answered in the article.

From the history of endotracheal anesthesia

For the first time this type of anesthesia was tried in the 14th-15th centuries, when a physician Paracelsus from Switzerland injected a tube into the trachea of a man, thus saving his life. Three centuries later, people saved themselves from lack of air in this way. In 1942, an anesthesiologist from Canada for the first time used muscle relaxants - substances that reduce the tone of skeletal muscles until complete immobilization. Thanks to this discovery, anesthesia became safer and more perfect, allowing specialists to fully control the course of surgical sleep during the operation.

In the middle of the 20th century, endotracheal anesthesia began to develop rapidly, which was facilitated by Soviet physicians. Today, this is the most common method of general anesthesia, used in most operations.

Endotracheal Anesthesia: What is it?

In order to protect the body from tremendous stress during surgery, anesthesia is used. It can be local, regional or general. The latter is called anesthesia. It is characterized by a complete "shutdown" of the patient's consciousness with the onset of surgical sleep. In modern anesthesiology, intravenous, mask or combined anesthesia is used. The latter combines two methods: substances enter both the blood and the respiratory tract. This form is called endotracheal anesthesia.

Experts rightfully consider it to be the safest and most effective method of anesthesia: it allows you to fully control the patient's condition, achieve deep surgical sleep and relax skeletal muscles, and avoid such unpleasant complications as aspiration and respiratory failure.

Indications

Endotracheal anesthesia protects the patient from pain shock and respiratory failure, which allows using it during the operation and resuscitation. Among the indications for combined anesthesia may be:

• Surgery on the mediastinum, pharynx, inner ear, oral cavity and head;
• Interventions in which it is necessary to use muscle relaxants;
• Malfunctions in the nervous system;
• Full stomach syndrome;
• Risk of violation of airway patency.

Endotracheal general anesthesia is more often used for long-term operations, which last more than 30 minutes. It can be used at any age in different conditions of the patient, because it does not load the heart and is much less toxic to other methods of anesthesia.

Contraindications

Planned surgical treatment (for example, surgery to remove the tumor of the mediastinum) is accompanied by a thorough study of the patient's condition. The doctor has the necessary time to get acquainted with the patient's medical record, having time to calculate possible risks and to identify contraindications to this or that method of anesthesia. Combined anesthesia is not recommended in the following conditions:

• infectious diseases;
• Pathology of the liver, kidneys;
• Suspected myocardial infarction;
• Pathology of the respiratory tract;
• Physiological features of the structure of the pharynx;
• Severe endocrine disorders.

Especially dangerous is the use of endotracheal anesthesia in upper respiratory tract infection, because the risk of contracting the lungs is high.

Stages of combined anesthesia

So, endotracheal anesthesia. What is this for the doctor? Anesthesiologist performs three consecutive stages of action: introduction to surgical sleep, maintaining a stable state and awakening. The first stage consists in the implementation of a light initial anesthetic. The patient receives drugs intravenously or inhales a mixture of gases. When the muscles are completely relaxed, the anesthesiologist inserts an intubation tube into the lumen of the trachea. It provides ventilation of the lungs with oxygen and inhalation with gaseous anesthetics.

After the surgeons have completed their work, the responsible moment for the anesthesiologist comes - the withdrawal of the patient from anesthesia. Dosage of drugs is gradually reduced. After restoration of independent breathing, extubation is carried out - removal of the intubation tube from the trachea. The patient is transported to the intensive care unit, observing the vital signs and the process of postoperative recovery.

Introductory anesthesia

An easy initial anesthesia is necessary for painless and safe intubation, without which endotracheal anesthesia is not possible. To achieve this state, inhalations or intravenous pain medications are used. In the first case, the patient breathes through the mask with "Etran", "Forana", "Ftorotan" or other similar mixtures of anesthetics. Sometimes there is enough nitrous oxide with oxygen.

As medications administered intravenously, barbiturates and neuroleptics (droperidol, fentanyl) are commonly used. They are used in the form of a solution (not more than 1%). The dose of the drug is selected by an anesthesiologist individually for each patient.

After a slight anesthesia has affected, intubate trachea. For this, muscle relaxants are used to relax the muscles of the neck. The tube is injected with a laryngoscope, after which the patient is transferred to an artificial lung ventilation. The stage of deep anesthesia begins.

Дроперидол: the instruction

Droperidol is an antipsychotic often used in endotracheal anesthesia. By chemical structure, this substance is a tertiary amine. Has a sedative effect as early as 3 minutes after injection. It blocks dopamine receptors, which causes neurovegetative inhibition. In addition, it has antiemetic and hypothermic action. Breathing affects slightly.

It is prescribed for premedication, introductory anesthesia, myocardial infarction, shock state, severe angina pectoris, pulmonary edema and hypertensive crisis. It is recommended as a drug that eliminates nausea and vomiting. It has low toxicity, which allows it to be used in pediatric surgery and obstetrics.

Method of using antipsychotics for introductory anesthesia

There are several options for performing neuroleptanalgesia. Introductory anesthesia is usually carried out according to the following scheme: droperidol, the instruction of which was considered above, in an amount of 2-5 ml with 6-14 ml of fentanyl is intravenously administered to the patient. At the same time, apply a mask with a mixture of nitrous oxide and oxygen in a ratio of 2: 1 or 3: 1. After the depression of consciousness, muscle relaxants are injected and intubation is started.

Droperidol has an antipsychotic effect for 4-5 hours, so it is administered at the beginning of anesthesia. Calculate it with allowance for body weight: 0.25-0.5 mg / kg. Re-introduction of the drug is necessary only for prolonged operations.

Fentanyl in the amount of 0.1 mg is administered every 20 minutes and its supply is stopped 30-40 minutes before the end of the surgical procedure. The initial dose is 5-7 μg / kg.

Intubation

After depression of consciousness spend artificial ventilation of lungs by oxygen with the help of an anesthetic mask. Then the doctor performs intubation through the mouth (less often through the nose). Head throws back, mouth opens. Introduce a laryngoscope with a straight blade along the middle line between the sky and the tongue, pressing the latter up. Pushing the instrument further, raise the apex of the epiglottis. A voice gap is inserted into which the intubation tube is inserted. It should go into the trachea for about 2-3 cm. After successful intubation, the tube is fixed and the patient is connected to the ventilator.

Less commonly used laryngoscope with a curved blade. It is introduced between the base of the epiglottis and the root of the tongue, pushing the latter upward from itself. If the tube can not be inserted through the mouth, use the lower nasal passage. For example, an operation is performed to remove the oral cyst.

Maintaining and getting out of anesthesia

After intubation and connection of the patient to the ventilator , the main period begins. Actively working surgeons, the anaesthesiologist closely watches indicators of life-support. Every 15 minutes they check the heart rate, blood pressure, monitor the patient's cardiac activity with the help of monitors.

General anesthesia is maintained with the help of additional doses of neuroleptics, muscle relaxants or inhalations with mixtures of anesthetics. Operation under anesthesia combined type allows you to adjust the anesthesiologist for the needs of the body in anesthesia, providing an optimal level of safety.

After the end of surgical manipulation, the last stage comes - the way out of the narcotic sleep. Before the onset of this point, the dosage of drugs is gradually reduced. To restore breathing, enter atropine and proserine at intervals of 5 minutes. Having convinced that the patient is able to breathe independently, extubation is carried out. To do this, clean the area of the tracheobronchial tree. After the removal of the tube, a similar procedure is performed with the oral cavity.

Postoperative surveillance

After leaving the operating room, the patient is located in the intensive care unit, where a thorough control of his condition is carried out. After a general anesthesia unpleasant sensations develop, less often complications. Typically, postoperative patients complain about:

• Pain;
• Feeling of discomfort in the throat;
• Nausea;
• Weakness and muscle fatigue;
• drowsiness;
• Confusion;
• chills;
• Thirst and lack of appetite.

These symptoms usually occur within the first 2-48 hours after surgery. To eliminate pain, analgesics are prescribed.

So, let's sum up. Endotracheal Anesthesia - What Is It? This is a method of introducing a person into a surgical dream, which allows performing complex operations, controlling the activity of the respiratory system. Combined anesthesia is less toxic, and the depth of anesthesia is easily controlled during the entire period of intervention. Under endotracheal anesthesia, intubation is first and then connected to the ventilator. In this case, both inhalation and drug anesthetics are used, which are usually combined.