Bronchiectasis.
Refers to irreversible damage to the bronchial wall due to congenital or acquired factors that cause dilatation of the bronchi (part of the respiratory tract) and obstruction of the lumen, often accompanied by bronchiectasis and cystic fibrosis of the lungs. It is classified as an obstructive lung disease. The disease was first discovered in 1819, and he was also the inventor of the stethoscope. The theory of bronchiectasis was further refined in the 1800s by the famous Canadian physician Osler, who was also later thought (and not diagnosed) to have died from complications of bronchiectasis.
Bronchiectasis (bronchiectasis) may involve multiple regions of the lung and is called diffuse, or it may involve only one or two regions and is called restrictive. Typical bronchiectasis causes damage to only moderate caliber bronchi, but scarring and destruction of even smaller bronchi is often seen.
Pathogenesis.
Bronchiectasis can result from direct damage to the bronchial wall or indirect damage due to disruption of the normal defense mechanisms of the respiratory tract.
The defense mechanism of the respiratory tract includes the cellular cilia on the surface of the respiratory tract, which constantly move back and forth to expel the thin mucus (sputum) that is covered on the surface of the respiratory tract, and also to expel the harmful particles and bacteria deposited in the respiratory mucus.
Regardless of direct or indirect damage to the respiratory tract, chronic inflammation of the bronchial wall occurs, causing loss of elasticity of the bronchi, resulting in dilatation, relaxation and expansion of the respiratory tract in the form of a thin-walled sac; inflammation also increases mucus secretion; due to the destruction of ciliated cells, this mucus collects in the dilated respiratory tract, nourishing the reproduction of bacteria. Bacteria further damage the tracheal wall, leading to a vicious cycle of infection and bronchial damage.
In summary, bronchial dilatation is irreversible because of: increased mucus secretion (sputum), destruction of cilia of cells, and destruction of bronchial walls due to chronic inflammation.
Etiology.
There are two types of etiologies, congenital and acquired.
Congenital causes: The following genetic disorders can cause bronchiectasis: primary ciliary dyskinesia (Kartagener syndrome), which impairs the movement of cilia in the bronchial wall and leads to bronchiectasis. A small percentage of patients with cystic fibrosis of the lungs can develop severe bronchiectasis. young syndrome, which resembles cystic fibrosis clinically, has conditions such as bronchiectasis, sinusitis and low fertility (sperm deficiency), which is associated with obstruction of the bronchi and vas deferens containing large amounts of mucous secretions. Patients with alpha-antitrypsin deficiency are also highly susceptible to bronchiectasis for unknown reasons. Other rare congenital causes include: primary immunodeficiency; bronchiectasis can sometimes be combined with inflammatory bowel disease, especially ulcerative colitis and occasionally Crohn’s disease.
The most common cause is acquired, i.e. caused by severe or recurrent respiratory infections, with the highest incidence of endobronchial tuberculosis. Other etiologies include immune deficiency, mechanical factors (e.g., airway obstruction due to respiratory tumors or inhalation of foreign bodies, inhalation of toxic fumes, smoking, and inhalation of noxious particles such as silica and coal dust).
Other diseases that occasionally involve the airways, namely: allergic bronchopulmonary aspergillosis, which often occurs in asthmatic patients and which is a metabolic disease to Aspergillus, can cause sputum clots to obstruct the airways and lead to bronchodilation. Recent studies have shown that patients with rheumatoid arthritis who smoke are at high risk for bronchiectasis.
Bronchiectasis staging.
Depending on the severity of the lesion, bronchiectasis is divided into three types: fusiform (cylindrical) bronchiectasis, the most common, which is a mild inflammation of the bronchi that disrupts the normal bronchial morphology of the distal tapering; varicose bronchiectasis, in which the bronchial wall is beaded, due to the morphology of mixing the dilated and narrowed portions of the bronchi; and cystic bronchiectasis, characterized by a severe, irreversible ballooning of the peripheral bronchi, which may be accompanied by or without air-fluid flattening.
Symptoms.
Bronchiectasis can occur at any age, with primary symptoms often presenting in early childhood or adolescence, but patients are most often diagnosed after the age of 20 years. Symptoms show a progressive worsening after a pulmonary infection and persist for years. The most typical symptoms are chronic cough, sputum, hemoptysis, recurrent fever and chest pain, with or without pneumonia, wasting, and anemia.
Most patients present with a chronic cough and sputum, which may be white, yellow-green, foul-smelling or bloody, and is evident with changes in position (e.g., lying in bed, on one’s side, etc.).
The amount of coughing sputum is related to the extent of lesion involvement and whether it is complicated by infection, usually heavy in the morning and light in the evening, and is often accompanied by hemoptysis due to damage to the bronchial walls of the brittle, multivascularized bronchi.
Patients with extensive bronchiectasis may present with wheezing or shortness of breath, and those who have developed pulmonary heart disease or respiratory failure may also present with easy fatigue, lethargy, and dyspnea, symptoms that are more pronounced after activity.
Of those who cough up pus for a long time have bronchiectasis, and 70% of patients with bronchiectasis cough up sputum every day. Patients with bronchiectasis are initially susceptible to Haemophilus influenzae infection, while secondary infections are usually Staphylococcus aureus, followed by Moraxella mucosae, and finally Pseudomonas aeruginosa infection.
Complications.
Recurrent infections and inflammatory reactions in the small airways of the lungs can lead to pneumonia, scarring and pulmonary decompensation. Severe pulmonary scarring and pulmonary hypoplasia eventually lead to right heart failure, known as pulmonary heart disease.
Very severe branched dilatation forming progressive cystic fibrosis of the lung is most often seen in underdeveloped countries or regions, and its impairment of lung function can lead to decreased blood oxygen levels and increased carbon dioxide levels, which is known as respiratory failure.
Diagnosis.
The doctor will consider the diagnosis of bronchiectasis based on the patient’s current or past symptoms and presentation. Abnormal breath sounds are often heard on auscultation, and the doctor will perform targeted tests to clarify the diagnosis and assess the extent and location of the lesion.
Chest X-ray is the most commonly used test, but occasionally the chest X-ray is normal. At present, high-resolution CT of the chest has replaced the traditional bronchial iodine-oil imaging as the gold standard for the diagnosis of bronchiectasis, which can clarify the diagnosis and determine the location, extent and scope of the lesion.
After the diagnosis of bronchiectasis, a number of tests will be done to investigate the cause of bronchiectasis, these tests include.
1. measuring the level of a certain protein in the blood.
2. checking for HIV infection or other immune dysfunctional diseases
3. determination of the salt content of sweat, which is abnormal in patients with cystic fibrosis
4. nasal and bronchial or sputum smears and bacterial cultures.
5. bronchoscopy to exclude inhaled bronchial foreign bodies or tumours if the bronchial dilatation is confined to only one area, such as within one lobe of the lung or one lung segment
6. other tests for structural and functional damage to mucosal cilia
7. examinations to exclude tuberculosis, certain fungal infections, tumors, etc.
8, allergic bronchopulmonary aspergillosis.
9, genetic determination is required to exclude pulmonary cystic fibrosis in patients with a family history and recurrent respiratory infections in young children who present with cystic fibrosis.
Prevention
Early diagnosis and treatment of diseases that predispose to bronchiectasis can prevent its development or reduce its severity. More than half of the patients with bronchiectasis are diagnosed accurately and treated aggressively in childhood. It is important to note, however, that some patients with bronchiectasis are not preventable.
Improving the quality of life and good nutritional status can undoubtedly significantly reduce the incidence of bronchiectasis, so a scientific view of diet (see the article on diet for tumor prevention on this site) and maintaining a normal body mass index should be established.
Vaccination: Vaccination against measles, rubella and pertussis during childhood, and annual vaccination against influenza and pneumococcal vaccine. Chest X-ray should be taken immediately after a child has severe measles, whooping cough or other lung infections.
Early treatment: Early application of appropriate antimicrobials (i.e., not to be abused or not to be used) in the early stages of a lung infection can help prevent bronchial expansion and reduce the severity of its onset.
Treatment of the primary disease: In those with allergic bronchopulmonary aspergillosis, appropriate application of hormones and antifungals can reduce bronchial damage and prevent bronchial expansion. For those with immunoglobulin deficiency syndrome, receiving immunoglobulin injections can prevent recurrent infections.
Respiratory protection: Avoiding inhalation of toxic fumes and harmful dusts and avoiding smoking can prevent bronchiectasis and reduce its attacks. Although there is no evidence that smoking can cause bronchiectasis, it is clear that smoking can irritate the patient’s bronchi and aggravate infections and other complications. Appropriate hand washing with hand sanitizers that have antibacterial properties.
Avoid inadvertent endotracheal aspiration: children should be promptly prevented from holding hard objects in their mouths, which can cause secondary bronchiectasis by inadvertent aspiration into the trachea. Avoid excessive sedation, intoxication, and neurological medications that cause loss of consciousness or gastrointestinal reactions. Also, do not inject Vaseline or mineral oil into the nasal cavity to prevent inadvertent aspiration into the lungs that cannot be expelled.
Self-care at home
Postural drainage: In the case of lower lobe bronchial dilatation (different methods of drainage for different lobe bronchial lesions are described in detail in a later article), the patient lies prone on the bed, with a pillow to elevate the buttocks, and the assistant taps the back corresponding to the lung to shake out the sputum, with the palm of the hand curved into a hollow pattern (see figure), the patient’s family should learn this home care method and treat 2-4 times a day for 10 minutes each time.
Nebulized inhalation: inhalation of warm moist air also helps to liquefy the thick sputum in the airway so that it can be coughed up. At the same time, the patient should try to avoid any gas that irritates the lungs, such as: smoke, second-hand smoke, dust, etc.
Medication: taking any medication must be medically prescribed by a doctor and followed.
Treatment.
The aim of bronchodilator treatment is: to control respiratory infections and inhibit bronchial secretion to relieve airway obstruction and prevent complications. The conservative treatment is to: prolong the use of antimicrobials to control the growth of harmful germs; and empty the accumulated sputum through postural drainage and chest physiotherapy. Therefore, patients often take large amounts of antimicrobials or other drugs for a long time to control infection and cough up sputum, resulting in many drug complications.
Surgery is the treatment of choice for restrictive bronchiectasis, which removes the lesion, eliminates the airway obstruction that allows the disease to progress, and preserves as many healthy lungs as possible.
Our hospital performed thoracoscopic lobectomy as early as December 4, 2007, and is the only hospital in China so far that has mastered this technique. The three incisions of the surgery do not exceed 2 cm, and are usually only about 1.5 cm, and the patient recovers quickly with significant symptom relief (for limited patients).
Treatment and prognosis
In the early stages of the disease, effective treatment reduces the complications of bronchiectasis, such as hemoptysis, hypoxemia, respiratory failure and pulmonary heart disease. The principles of treatment of bronchiectasis are complete elimination of infection, reduction of mucus retention, and release of airway obstruction.
Cough suppressants are not recommended because they contradict the above principles. Antibiotics, bronchodilators and physiotherapy to promote deep sputum drainage (postural drainage and back patting) should be used to control the infection, and sometimes, especially in patients with cystic fibrosis, antibiotics may be given for a longer period of time to prevent recurrent infection.
Corticosteroid inhalers and phlegmolytics can reduce airway narrowing, thinning of sputum and ease of expulsion in patients with inflammation and sputum retention, which can stop the progression of the disease to some extent.
Mannitol dry powder inhalers, although only clinically used in a few countries, have been approved by the FDA for individual cases of bronchiectasis and pulmonary cystic fibrosis.
Postural drainage and chest percussion are very helpful in bronchial drainage. Bronchoscopy allows for prompt diagnosis and treatment before bronchial obstruction leads to serious damage. The diseased lung tissue can be removed if necessary, and if the lesion is confined to one lobe or segment of the lung, surgical treatment is usually the best option. Indications for surgery are: recurrent infections despite aggressive treatment, or those with massive hemoptysis. Alternative procedures to bronchial artery embolization have also been used to treat acute hemoptysis by injecting an obstruction into the bleeding artery through a catheter inserted into the vessel to achieve temporary hemostasis.
If the patient has hypoxemia, oxygen therapy is required, and proper oxygen therapy can prevent complications such as pulmonary heart disease. If the patient has asthma or dyspnea, oral or inhaled corticosteroids and often concomitant bronchodilators are administered. If respiratory failure develops, the physician will be more aggressive in taking the necessary measures.
Some patients with advanced disease are candidates for lung transplantation, and such patients often have advanced cystic fibrosis of the lungs. The 5-year survival rate for heart-lung or double-lung transplantation is 65% and 75%, and lung function tends to improve within 6 months after transplantation and is maintained for at least 5 years.
Prognosis: The prevention and control of infections and other complications of bronchiectasis determines the patient’s prognosis. Patients with comorbidities such as chronic bronchitis or emphysema, and those with complications such as pulmonary hypertension or pulmonary heart disease, that is, hypoxemia, hypercapnia, dyspnea and extensive lesions, have a tendency to have a poorer prognosis.