I. Definition of cough
1. cough is one of the most common symptoms of the respiratory system.
2. Coughing is first a rapid short inspiration, with the diaphragm falling and the vocal chambers closing rapidly, followed by rapid contraction of the respiratory and abdominal muscles, causing a rapid rise in intrapulmonary pressure; the vocal chambers then suddenly open, with high-pressure airflow ejected from the lungs, impacting on the vocal chambers cracks and resulting in coughing action and special sound, with the discharge of secretions or foreign bodies, etc., from the respiratory tract.
II. Pros and cons of coughing
Coughing is a protective respiratory reflex of the body. The cough reflex is effective in removing secretions or foreign bodies from the airways. However, there are also disadvantages to coughing, such as prolonged, frequent and violent coughing that interferes with work and rest, and even causes sore throat, hoarseness and respiratory muscle pain, and violent coughing can lead to respiratory bleeding.
C. Causes of cough
1. Inhalants Inhalants are divided into two types: specific and non-specific. The former are such as dust mites, pollen, fungi, animal dander, etc.; non-specific inhalants such as sulfuric acid, sulfur dioxide, chloramine, etc. The specific inhalants for occupational cough are such as toluene diisocyanate, phthalic anhydride, ethylenediamine, penicillin, protease, amylase, silk, animal dander or excrement, etc. In addition, the non-specific ones are also formaldehyde and formic acid, etc.
2. Infection The formation and onset of cough is associated with recurrent respiratory infections. In patients with cough, there can be specific IgE of bacteria, viruses, mycoplasma, etc., which can stimulate coughing if the corresponding anti-principles are inhaled. After viral infections, direct damage to the respiratory epithelium can occur, resulting in increased respiratory reactivity. It has been suggested that histamine release from basophils is increased by interferon and IL-1 produced by viral infections. Cough caused by parasites such as roundworms and hookworms can still be seen in rural areas.
3. Food Cough attacks due to dietary relations are often seen in cough patients, especially in infants and children who are prone to food allergies, but gradually decrease with age. The most common foods that cause allergies are fish, shrimp and crabs, eggs, milk, etc.
4. Climate change Cough can be triggered when the temperature, humidity, air pressure and/or ions in the air change, so there is more incidence in the cold season or in autumn and winter when the climate changes.
5. Mental factors Patients’ emotional excitement, nervousness and anger can prompt coughing episodes, which are generally thought to be caused by the cerebral cortex and vagal reflexes or hyperventilation.
6. Exercise About 70% to 80% of patients with cough induce cough after strenuous exercise, which is called exercise-induced cough, or exercise cough. Clinical manifestations include cough, chest tightness, shortness of breath, and wheezing, and croup can be heard on auscultation. In some patients, although there is no typical asthma manifestation after exercise, bronchospasm can be detected by pulmonary function measurements before and after exercise.
7. Cough and drugs Some drugs can cause coughing attacks, such as the ACEI class drug captopril.
IV. Classification of cough
1. Acute cough (8 weeks)
V. Diagnosis and differential diagnosis of cough
Since cough is a non-specific symptom of many diseases, a detailed clinical history, comprehensive physical examination, chest X-ray or CT, airway reactivity measurement, pulmonary function, electrocardiogram, fiberoptic bronchoscopy and some special tests must be performed to exclude other diseases that can cause chronic and persistent cough for diagnosis and differential diagnosis.
VI. Principles of cough treatment
1.Treatment of the cause
2. Symptomatic treatment
VII. Definition of chronic cough
Chronic cough: a cough that lasts for more than 8 weeks and can last for several years or even decades.
Etiology of chronic cough
The causes of chronic cough are more complex and commonly include
1. cough variant asthma (allergic bronchitis)
2. posterior nasal drip syndrome
3. gastroesophageal reflux
4. eosinophilic bronchitis
5, chronic bronchitis
6.Cardiogenic cough
7, Drug-induced
Auxiliary examination
(1) Induced sputum examination: It was first used for the diagnosis of bronchial lung cancer, and the positive rate of cancer cell examination can be significantly increased by induced sputum cytology examination, which is even the only diagnostic method for some early lung cancers. Increased eosinophils in cytology examination is the main indicator for the diagnosis of EB.
(2) Imaging X-ray chest radiographs can determine the location, extent and morphology of lung lesions, and even their nature, leading to a preliminary diagnosis and guiding empirical treatment and correlative examinations. X-ray chest radiographs are recommended as a routine examination for chronic cough, and if organic lesions are found, relevant tests are selected according to the characteristics of the lesion. x-ray chest radiographs without obvious lesions are examined according to the chronic cough diagnostic procedure (see Chronic Cough Diagnostic Procedure). CT chest examination helps to detect anterior and posterior mediastinal lung lesions, small intrapulmonary nodules, enlarged mediastinal lymph nodes and smaller masses within the marginal lung fields. High-resolution CT helps to diagnose early interstitial lung disease and atypical bronchiectasis
(3) Pulmonary function tests: Ventilation function and bronchodilation tests can help diagnose and identify airway obstructive diseases such as asthma, chronic bronchitis and large airway tumors. Routine lung function is normal, and CVA can be diagnosed by excitation test.
(4) Fiberoptic bronchoscopy (referred to as fiberoptic bronchoscopy): it can effectively diagnose lesions in the tracheal lumen, such as bronchopulmonary cancer, foreign bodies, and endothelia tuberculosis.
(5) Esophageal 24h pH monitoring: It can determine the presence of gastroesophageal reflux (GER), and is the most effective method to diagnose GERC. By dynamically monitoring the change of esophageal pH, 24h esophageal pH is obtained