What Is Endotracheal Anesthesia?

Endotracheal intubation is the most effective and reliable method of establishing an artificial airway. It refers to the technique of placing a special tracheal tube through the mouth or nasal cavity through the glottis into the trachea. This technology can relieve the respiratory tract. Obstruction, to ensure the patency of the airway, to remove respiratory secretions, to prevent aspiration, to assist or control breathing, etc. provide the best conditions. Commonly used for tracheal anesthesia and rescue of critically ill patients.

Basic Information

English name

intratracheal intubation

Visiting department

Department of Anesthesiology

Indications for endotracheal intubation

1. Respiratory insufficiency or respiratory failure, need to pressurize oxygen and assist breathing.

2. It is convenient for airway management and intratracheal administration during general anesthesia.

3. Cardiopulmonary resuscitation with cardiac arrest and respiratory arrest.

4. Respiratory secretions cannot cough up on their own, and need to be attracted by the trachea.

5. The gastric contents are inhaled into the lungs by mistake and need to be attracted by the trachea.

6. Intratracheal intubation positioning before infant tracheotomy ^[1] .

Contraindications for endotracheal intubation

Absolute contraindication

Laryngeal edema, acute laryngitis, laryngeal submucosal hematoma, and traumatic intubation can cause severe bleeding. Intratracheal intubation is contraindicated in the above cases unless the patient is in emergency.

2. Relative contraindications

(1) Patients with incomplete airway obstruction have indications for intubation, but rapid induction of intubation is contraindicated.

(2) For coexisting hemorrhagic blood diseases (such as hemophilia, thrombocytopenic purpura, etc.), traumatic intubation can easily cause bleeding or hematoma in the throat, glottis or trachea, and secondary acute obstruction of the respiratory tract.

(3) If the aortic aneurysm compresses the trachea, intubation may cause the aneurysm to rupture, which is a relative contraindication. If tracheal intubation is required, it must be proficient and lightweight to avoid accidental trauma.

(4) The nasal passage is not smooth. Nasopharyngeal fibrous hemangiomas, nasal polyps, or those with a history of repeated nosebleeds are contraindicated by endonasal intubation.

(5) Operators who do not master the basic knowledge of intubation, are not skilled in intubation technology, or have incomplete intubation equipment, should be listed as relative contraindications ^[2] .

Examination and evaluation of tracheal intubation

Before endotracheal intubation, relevant examinations (nasal cavity, teeth, mouth opening, neck mobility, throat condition) should be performed routinely, and the following issues should be decided: which intubation route (oral or nasal) to use and Anesthesia method (general anesthesia or sobriety); Whether there is difficulty in intubation and what intubation method should be adopted to solve it ^[3] .

Endotracheal intubation method

Oral vision intubation

After exposing the glottis under direct vision with the help of a laryngoscope, the catheter was inserted into the trachea through the mouth.

(1) Tilt the patient's head first. If the patient's mouth is not open, the thumb of the right hand can be used to face the lower dentition, and the index finger should be facing the upper dentition.

(2) Hold the left laryngoscope into the mouth from the corner of the right mouth, push the tongue to the left, and slowly push forward, revealing the drooping (uvula), and then go forward slightly, so that the front of the curved laryngoscope peephole enters The tongue base and the epiglottic angle, and then rely on the strength of the left arm to raise the laryngoscope upward and forward, and increase the tension of the hyoid bone epiglottis ligament to reveal the glottis. In the case of a straight laryngoscope, the front end of the laryngoscope should lift the epiglottis cartilage to reveal the glottis.

(3) When the glottis is clearly exposed, hold the middle and upper sections of the catheter with the thumb, index finger and middle finger of the right hand, such that the front end of the catheter enters the mouth from the right mouth corner, and then move the tube end to the throat when the catheter approaches the throat. At the lens, monitor the advancing direction of the catheter through the narrow gap between the lens and the tube wall at the same time, and insert the tip of the catheter accurately and lightly into the glottis. When intubating with a core, when the tip of the catheter enters the glottis, the catheter should be pulled out before inserting the catheter into the trachea. The depth of insertion of the catheter into the trachea is 4-5 cm for adults, and the distance from the tip of the catheter to the incisors is 18-22 cm. Place the dental pad and exit the laryngoscope.

2. Nasal vision intubation

This method is basically the same as the oral intubation method, but has the following differences.

(1) Drop the liquid paraffin into the nasal cavity before intubation, and apply lubricant to the front of the catheter. Awake intubation requires anesthesia on the inner surface of the nasal cavity.

(2) To master the operation of the catheter along the lower nasal passage, that is, the catheter must be inserted into the nostril perpendicular to the face, and the posterior nasal orifice along the bottom of the nose to the pharyngeal cavity. Do not push the catheter to the top of the head, otherwise it will cause serious Bleeding.

(3) The distance from the nose to the earlobe is equal to the distance from the nostril to the posterior pharynx. After the catheter is advanced to the above distance, the glottis is exposed with the left hand laryngoscope. Continue to push the catheter into the glottis with your right hand. If you have difficulty, you can use the intubation forceps to clamp the front end of the catheter into the glottis.

(4) Transnasal catheters are prone to inflection at the posterior nostril and difficult to handle. For this reason, the texture of the catheter should be checked in advance, and a tough and elastic catheter that is not easy to bend and flatten should be selected.

3. Intranasal blind intubation

The tracheal tube is inserted into the trachea through the nasal cavity under non-vision conditions.

(1) The nasal patency should be checked for abnormality first. Spontaneous breathing with a large ventilation volume must be retained during intubation. The direction of the catheter's forward direction can be judged based on the strength of the exhaled airflow.

(2) Use 1% tetracaine as an anesthesia on the inner surface of the nasal cavity, and instill 3% ephedrine to constrict the blood vessels in the nasal mucosa to increase the volume of the nasal cavity and reduce bleeding.

(3) Select a tracheal tube with a suitable diameter, apply paraffin oil or local anesthetic ointment to the outside of the catheter, hold the tube in the right hand, and slowly introduce the tube from the nostril. The position and distance between the oblique end of the catheter and the glottis need to be determined by the strength or absence of the sound of the breathing airflow in the duct; the more the duct opening is facing the glottis, the louder the airflow sound is; The lighter or no sound. At this time, the operator adjusts the head position with the left hand and palpates the skin of the anterior neck area to understand the position of the front end of the catheter; while the right hand adjusts the position of the front end of the catheter while listening to the sound of airflow with the ear. When adjusted to the loudest part, slowly advance the catheter into the glottis.

(4) Quickly advance the catheter when the glottis is open. When the catheter enters the glottis, the propulsion resistance is reduced, and the exhaled airflow is obvious. Sometimes the patient has a cough reflex. When the anesthesia machine is connected, the breathing sac expands and contracts as the patient breathes, indicating that the catheter is inserted into the trachea.

(5) If the exhaled airflow disappears after the catheter is advanced, it is a manifestation of insertion into the esophagus. The catheter should be retracted to the nasopharynx, and the head should be slightly tilted so that the tip of the catheter is tilted upwards, which can be aligned with the glottis to facilitate insertion.

4. Awake tracheal intubation

Use 1% tetracaine to spray the throat and trachea to perform mucosal surface anesthesia, and perform endotracheal intubation in the patient's conscious state, which is called "wakeful intubation", referred to as "wakeful intubation". When the intubation of a patient under general anesthesia is not safe, conscious intubation can be used.

(1) Surface anesthesia requires a complete mucosal surface anesthesia for the upper respiratory tract before intubation, including throat mucosal surface anesthesia and tracheal mucosal surface anesthesia.

(2) Sedative intubation by oral or nasal awake requires patients to be fully sedated and muscles loosened throughout the body. This will not only help the intubation, but also basically avoid unpleasant memories after surgery.

(3) Preparation of patients The patient must be properly explained, focusing on cooperating matters, such as relaxing the muscles of the whole body, especially the muscles of the neck, shoulders, and back, without straining or disturbing; maintaining deep and slow breathing without holding your breath, Do not be nauseous, etc., try to win the patient's full cooperation; The use of appropriate pre-anesthetic drugs can reduce patient secretions and sedative throat reflexes, which is conducive to conscious intubation.

(4) After the intubation of the laryngotracheal mucosa, the conscious tracheal intubation can be performed 1 to 2 minutes after the intubation of the laryngotracheal mucosa.

Endotracheal intubation confirms correct catheter position

Regardless of the endotracheal intubation method, after the intubation is completed, it is necessary to confirm that the catheter has entered the trachea and then fixed. Judging methods are:

1. When the chest is pressed, there is air flow at the mouth of the catheter.

2. During artificial respiration, symmetrical undulations on both sides of the thorax can be seen, and clear breathing sounds can be heard.

3. When using a transparent catheter, the wall of the tube is clear when inhaling, and obvious "white fog" -like changes can be seen when exhaling.

4. If the patient breathes spontaneously, the breathing sac will expand and contract with the breathing machine.

5. If you can monitor the end-expiratory carbon dioxide (PETCO ₂ ), it will be easier to judge, and the PETCO ₂ graphics can be displayed to confirm the error.

Complications of tracheal intubation

Respiratory tract injury

The laryngoscope is a metal device. The endotracheal tube is a foreign body. It can cause tooth loss during intubation, or damage the mucous membranes of the mouth, nasal cavity and throat, causing bleeding and edema of the throat. Long-term indwelling of the catheter may even cause granuloma of the throat.

2. Excessive stress

Endotracheal intubation is the strongest stimulus to patients during anesthesia and surgery. Endotracheal intubation under shallow anesthesia can cause severe coughing, belching or bronchospasm, and sometimes cardiac events due to excessive autonomic nervous system excitement Bradycardia, arrhythmia, and even sudden cardiac arrest or tachycardia, increased blood pressure, ventricular premature beats, and ventricular fibrillation. Therefore, sufficient anesthesia depth should be achieved before endotracheal intubation. Muscle relaxants can be applied to completely relax the throat muscles, reduce the irritation of the throat when the catheter passes through the glottis, or perform anesthesia on the surface of the throat and trachea to reduce Regardless of the stress response, these measures are particularly important for patients with hypertension and heart disease.

3. Respiratory obstruction or atelectasis

Blocking the catheter due to compression and twisting will increase the resistance to breathing; there are many secretions in the respiratory tract, which cannot be sucked out in time. After a long time, the secretions accumulate and dry in the catheter, narrowing the inner diameter of the catheter and even blocking it. Catheters that affect the patient's normal ventilation and cause carbon dioxide retention. The endotracheal tube was intubated too deep, accidentally entered the bronchi, and one side of the lung was not ventilated, causing hypoventilation, hypoxia, or postoperative atelectasis.

Endotracheal Intubation Nursing

1. Tracheal tube fixation

The soft-shaped tracheal intubation should be fixed together with the hard tooth pad. It can be double-fixed with adhesive tape and tape to prevent displacement or detachment. The tape should not be too tight to prevent deformation of the lumen. Regularly measure the tracheal intubation and the scale in front of the incisors and record it. At the same time, restrain the hands with a restraint band to prevent the patient from extubation or damaging the throat when he or she is awake or complicated with mental symptoms. Replace dental pads and tapes daily, and perform oral care.

2. Keep the tracheal tube open

Suction the oral cavity and tracheal secretions in time, pay attention to aseptic operation when sputum suction, mouth, tracheal suction tube must be strictly separated. The suction tube and oxygen suction tube should not exceed 1/2 of the inner diameter of the tracheal tube, so as not to block the airway. Each suction is done one tube at a time, and the suction tube stays in the airway for less than 15 seconds.

3. Keep the airway moist

The concentration of oxygen inhalation should not be too large, generally 1 ~ 2L / min is appropriate. The oxygen inhalation needle is inserted halfway into the tracheal tube. When the sputum is viscous, inhale it every 4 hours, or drip the humidified solution into the trachea, 2 to 5 ml each time, and no more than 250 ml in 24 hours.

4. Keep track of the location of the tracheal tube

You can know the position and depth of the catheter by auscultating the breathing sounds of the lungs or X-rays. If the breathing sounds disappear on one side, it may be that the trachea is inserted into one lung and needs to be adjusted in time.

5. Suitable airbag elasticity

Deflate every 4 hours for 5-10 minutes. Before exhaling, suck up the oropharynx and tracheal secretions. After 72 hours of tracheal catheter retention, tracheotomy should be considered to prevent the balloon from compressing the tracheal mucosa for a long time, causing ischemia and necrosis of the mucosa.

Endotracheal extubation

1. Extubation indications: The patient is conscious, the vital signs are stable, the cough reflex is restored, the sputum is strong, and the muscle tone is good, you can consider extubation.

2. Explain to the patient well before extubation, prepare an oxygen mask or nasal cannula.

3. Aspiration of oral secretions, full suction of sputum in the trachea, and pressurized oxygen with a breathing sac for 1 minute.

4. Unfasten the tape and tape of the tracheal tube, place the suction tube at the deepest point of the tracheal tube, suck the sputum while pulling the tube, and immediately give oxygen to the mask after pulling the tube.

Nursing after tracheal intubation

1. To observe the clinical manifestations of patients with hypoxia and dyspnea, such as nasal fans, shallow breathing, cyanosis, and increased heart rate.

2. Cut off the bag at the bed. For severe throat edema, tracheotomy was performed immediately after inhalation for 20 minutes or if dexamethasone was not relieved by intravenous drip.

References

1.MillerRD, etal.Miller'sAnesthesia [M] .6thed.Philadelphia: Churchill Livingstone, 2005: 1629-1646.

2. Zhuang Xinliang et al. Modern Anesthesiology [M]. Third Edition. Beijing: People's Medical Publishing House, 2004: 872-935.

3. Wang Chunting and others. Modern severe rescue technology [M]. First edition. Beijing: People's Medical Publishing House, 2007: 149-178.