iatrogenic trachea and main bronchus injury
Introduction
Introduction to iatrogenic trachea and main bronchial injury Iatrogenic tracheal injury refers to the organic damage of the trachea caused during the treatment process. The use of mechanical ventilation therapy in patients with severe respiratory failure increases the success rate of rescue and can also cause iatrogenic tracheal injury. basic knowledge Probability ratio: chest heart surgery is about 0.2% Susceptible people: no special people Mode of infection: non-infectious Complications: lung abscess pneumonia
Cause
The causes of iatrogenic trachea and main bronchial injury
Causes:
Airway injuries caused by endotracheal intubation include laryngeal injury by oral tracheal intubation, injury through tracheotomy or incision of the circumcision (Figure 1), and trachea due to excessive pressure in the cannula Wall compression necrosis.
Pathogenesis:
Endotracheal intubation can cause various types of injuries. The earliest appearance is necrosis caused by pressure. Nasal cartilage can also be involved. In the vocal cord of the throat, edema can be caused by stimulation, granuloma formation, and the joint part is damaged and localized. Scar fusion, endotracheal intubation caused by cartilage horizontal mucosal damage can cause subglottic stenosis, most children and adults due to endotracheal intubation caused by laryngeal injury can be repaired over time, some people think that ring nail Open can avoid the complications of tracheotomy, but can cause severe subglottic stenosis, local hormones have certain benefits for reducing the outcome of complications and injuries.
Tracheotomy is an ancient procedure. The indications for tracheotomy are upper tracheal obstruction and removal of endotracheal secretions, especially those with neurological deficits. In general, tracheostomy cannula is also placed in this case. In order to be used when the patient needs a long time for ventilator assistance, tracheotomy and placement of the tracheostomy can usually be retained for 1 week or longer. There has been a large amount of literature describing the immediate and early concurrency of tracheotomy. Symptoms, including cardiac arrest due to hypoxia during surgery; adjacent structures such as recurrent laryngeal nerve, damage to the esophagus and large blood vessels, pneumothorax, bleeding during surgery or shortly after surgery.
In the site of tracheotomy, the granuloma is often formed during the interstitial healing process. The lighter granuloma of the tracheotomy site can be removed by bronchoscopy, or there is no obvious clinical symptoms, but the tracheotomy Because the anterior wall of the trachea is lost in the stoma area, scar healing and granulation tissue proliferation can cause stenosis of the trachea. Other important causes of tracheal stenosis are:
1 intentionally or unintentionally make the stoma too large during the initial tracheotomy;
2 tissue defects caused by necrotic infection;
3 Applying the connection system of the breathing apparatus, the leverage of the external force oppresses the necrosis of the tracheal wall. The last factor is very important. Andrews and Pearson demonstrated this point in 1971. They believe that replacing the auxiliary breathing apparatus hardly connects the pipe and reduces the weight of the joint. Can significantly reduce the incidence of tracheotomy and stoma stenosis. Similarly, Geillo et al continue to use lighter connecting tubes in the early stage of tracheotomy and assisted breathing, which significantly reduces the incidence of tracheal stenosis. Conversely, many cases have inevitable segments. Sexual narrowness.
Another cause of horizontal obstruction of the tracheotomy is the tissue flap formed by the compression of the trachea incision around the stoma. The location is more common in the upper part of the tracheostomy. This type of injury can cause The cartilage and the subglottic laryngeal necrosis and inflammation change, therefore, in the first tracheotomy, try to avoid damage to the first cartilage ring, so as not to cause subglottic stenosis, in addition, if the tracheotomy of the stoma is low, it is possible Causes damage to the innominate artery or stenosis of the trachea on the bulge. If a certain pressure is added to the tracheal wall at the edge of the tracheostomy, the trachea incision is placed against the tracheal wall, causing necrosis of the tracheal wall. The incentives are multi-faceted, such as hypotension, bacterial infection, toxicity of tracheotomy, and plastic tube manufacturing. However, clinical experience and laboratory materials confirm that the direct cause of tracheal necrosis is tracheotomy. The high pressure around the opening, because the pressure on the edge of the tracheotomy is circumferential, the damage is also circumferential, if the deep tissue is involved, when healed The scar forms a circumferential stenosis, which can even cause complete occlusion of the trachea, causing death of the patient. If the pressure on the tracheotomy is large and lasts for a long time, the tracheal-esophageal fistula or trachea-invasive artery fistula Both may occur, and both types of injuries have higher mortality rates.
One of the late complications of tracheotomy is that the stoma is not closed 3 to 6 months after removal of the tracheotomy. This usually occurs when the tracheostomy tube is left in place for a long time, or the patient is lack of nutrients, long-term Applying high-dose hormonal and tracheotomy to patients with infection around the stoma. In such patients, the epithelial layer of the skin has been found to be connected to the tracheal epithelium at the edge of the tracheostomy, and the tracheostomy opening is observed after a sufficiently long observation period. If it still does not heal, surgical methods can be used to close the tracheostomy. The tracheotomy does not heal the patient, causing the patient to dislike, affecting the patient's speech, causing an increase in tracheal secretions, and may become a source of infection.
The cause of tracheal stenosis caused by tracheal intubation of the high-pressure cuff has been confirmed in the autopsy material of the patient with ventilator-assisted respiration before birth, and the results of these studies are consistent with those seen in surgical resection specimens, and such lesions have been modeled in experimental animals. It has been further confirmed that high-compatibility low-pressure cuffs have been used clinically so that the cuffs do not have excessive pressure on the trachea when the trachea is closed, and Grillo et al. reported in 1971 that the Massachusetts General Hospital has continued clinically. Intratracheal intubation with low-pressure cuff, no tracheal injury occurred due to tracheal cuff, the same low-pressure cuff was applied to the Toronto General Hospital in Canada, and the incidence of tracheal stenosis was zero in 100 patients. Instead, standard trachea was applied. The complication rate of cuff is 9%. Another way to solve the stenosis of the trachea is to deflate and re-inflate the balloon during the assisted breathing process. The child does not use the balloon when assisting breathing, but the cannula can be used. Tilting against the front wall of the trachea can also cause necrosis.
Tracheal softening is another complication of intubation injury that can occur in several segments. The most common site is the tracheal segment between the tracheostomy and the tracheal intubation cuff. Obviously, even if the trachea is maintained as much as possible. Clean inside, but there are still a lot of secretions accumulated here, inflammation changes make the tracheal cartilage thinner, although the mucosa has no ulcer, but the local tracheal segment becomes soft, which causes the tracheal collapse to cause functional tracheal obstruction, especially when the patient breathes hard Obviously, the short-segment tracheal softening is generally located in the high-pressure cuff portion of the tracheal intubation, as shown by the tracheal intubation caused by tracheal intubation after the common tracheotomy.
After tracheotomy, the trachea incision is sucked through the trachea. Because the tip of the suction tube always rubs, the trachea is infiltrated to cut the tracheal mucosa near the tip of the intubation, causing tissue edema, ulceration, and even more serious bleeding. Pay attention to prevention, the action of sucking should be gentle. Rinse the trachea with 5% NaHCO3 before sucking. Once bleeding occurs, drop a few drops of adrenaline or ephedrine into the tracheotomy tube to stop bleeding. Blood and clots in the trachea to prevent blood from flowing into the distal end causing pneumonia or obstruction, resulting in difficulty in ventilation.
The incidence of tracheal stenosis is slow, until the tracheal cavity is blocked more than 50% to 70%, the obvious symptoms appear, and the progress can be accelerated due to secondary infection, which can occur seriously within 1 month after injury. Tracheal obstruction or asphyxia.
Prevention
Iatrogenic trachea and prevention of main bronchial injury
Airway damage caused by endotracheal intubation in this disease includes laryngeal injury caused by oral tracheal intubation, injury caused by tracheotomy or circumcision, and tracheal wall compression due to excessive pressure of the intubated balloon Necrosis. Therefore, when intubating the tracheal intubation, it should be noted that the size of the incision and the pressure of the airbag should not be too large. Careful observation according to the regular operation procedure can avoid the occurrence of the disease.
Complication
Iatrogenic tracheal and main bronchial injury complications Complications, lung abscess, pneumonia
Pneumonia, lung abscess.
Symptom
Iatrogenic trachea and main bronchial injury symptoms Common symptoms Breathing difficulty Wheezing cough esophagus bronchial tree compression stomach dilatation respiratory failure
Most of the various injuries mentioned above are manifested as obstruction of the injury cross section. Clinically, the patient presents with extreme dyspnea and wheezing, even if a small amount of mucus in the tracheal cavity can cause obstruction. In radiology examination, Most of these patients have normal lung fields and are often misdiagnosed as "asthma". Many patients receive medical treatment, including large doses of hormones. A few patients have clinical manifestations of one or both pneumonia. It must be remembered that any Patients with symptoms of airway obstruction, such as the recent history of endotracheal intubation, should consider the possibility of tracheal injury before confirming the presence of other diseases.
Obstruction after tracheal injury can cause respiratory failure on the basis of the primary lesion. Although the lesion of the trachea will not further develop, the degree of tracheal stenosis can reach the extreme before dyspnea occurs. Clinical and experimental confirmation When the tracheal diameter is <10mm, the respiratory gas flow rate is reduced to 80% of normal. When the tracheal diameter is 5-6mm, the gas flow rate is reduced to 30% of normal. The narrower the trachea, the more obvious the gas flow rate decreases.
Tracheal esophageal fistula caused by tracheal intubation cuff compression, patients with dyspnea, gastric dilatation, a large amount of secretions in the tracheobronchial, patients with pneumonia, bronchial pneumonia and lung abscess, eating or swallowing toluidine blue, etc. After the dye, the food and dye will enter the trachea and cough up.
Trachea - the innominate arteries appear as a sudden large amount of blood entering the tracheobronchial, occasionally there are signs of bleeding, which may indicate that the tracheal-invasive arteries are about to occur. If the hernia is due to compression of the tracheal intubation cuff, there may be a chance to control bleeding. That is, the endotracheal tube with the high pressure cuff inserted again blocks the fistula. If the injury is caused by the tracheal intubation itself pressing the innominate artery, surgery should be performed immediately. Such conditions must be caused by severe tracheitis. Identification.
Examine
Examination of iatrogenic trachea and main bronchial injuries
Check the items in accordance with the actual situation of the patient.
Diagnosis
Diagnosis and diagnosis of iatrogenic trachea and main bronchial injury
Diagnosis is based on clinical manifestations. Generally not confused with other diseases.
