Causes of bronchial asthma
First, respiratory tract infection.
1. Respiratory virus infection: Respiratory syncytial virus (RSV), parainfluenza virus, influenza virus and adenovirus are the main types in infancy, and others such as measles virus, mumps virus, enterovirus and poliovirus are rare.
2. Mycoplasma infection: Due to the immature immune system of infants, mycoplasma can cause chronic respiratory infection in infants. If not handled properly, it will lead to repeated coughing and wheezing.
3. Focal infection of respiratory tract: Chronic sinusitis, rhinitis, otitis media and chronic tonsillitis are common chronic focal lesions in children's upper respiratory tract, which can cause recurrent infection on the one hand and recurrent cough and asthma through nerve reflex on the other, and these lesions need timely treatment.
Second, inhale allergic substances.
/kloc-children over 0/year old are gradually allergic to respiratory tract, such as indoor dust mites, cockroaches, pet fur, outdoor pollen, etc. Long-term continuous inhalation of low-concentration allergens can induce chronic airway allergic inflammation, cause body sensitization, produce chronic airway atopic inflammation, and promote the formation of BHR. With the increase of allergen exposure time, airway inflammation and BHR are gradually aggravated, which often develop into asthma in children. Short-term inhalation of high-concentration allergens can induce acute asthma, which occurs suddenly, mostly in the season of high allergen concentration in the environment.
Third, gastroesophageal reflux.
Because of anatomical structure, there are also iatrogenic factors (such as aminophylline and β -adrenergic drugs) that can cause gastroesophageal reflux, especially in infants, which is one of the important reasons for repeated wheezing. Clinically, it is often manifested as severe cough and wheezing during sleep, and generally there is a phenomenon of returning to milk or vomiting.
Fourth, genetic factors.
The prevalence rate of relatives of asthma patients is higher than that of the population. The closer the relatives are, the higher the prevalence rate is. The more serious the patient's condition is, the higher the prevalence rate of relatives is. At present, the genes related to asthma are not completely clear, but some studies show that there are many genes related to allergic diseases. These genes play an important role in the pathogenesis of asthma.
Five, other inhalation of irritating gases.
Or strenuous exercise, crying, paint, soot, cold air inhalation, etc. can be used as non-specific stimuli to induce asthma attacks. The gas emitted by paint can cause severe and persistent cough and asthma attacks, which should be avoided as far as possible. Violent exercise and crying can accelerate respiratory movement, reduce the temperature of respiratory tract or change the osmotic pressure of liquid in respiratory tract, thus inducing asthma attack.
Symptoms of bronchial asthma
Children's bronchial asthma can be divided into three types according to age and clinical manifestations: infantile asthma, childhood asthma and cough variant asthma.
First, the characteristics of infant asthma
1, cough and asthma are obvious in day or night, and get worse after exercise.
2. Pathologically, the main symptoms are mucosal swelling and hypersecretion, and the wheezing sound is low.
3. The response to corticosteroids is relatively poor.
4, prone to respiratory infections.
Second, the characteristics of childhood asthma
1, respiratory allergy gradually appeared after 2 years old.
2. The onset season is related to the type of allergen.
3, there is obvious smooth muscle spasm, wheezing pitch.
4. Good response to glucocorticoid.
Third, characteristics of cough variant asthma
1, long-term cough, no wheezing symptoms.
Cough becomes more serious at night or early morning and after strenuous exercise.
3. Antibiotic therapy is ineffective.
4, bronchodilators and glucocorticoids have special effects.
5. Some children have respiratory allergies.
Examination of bronchial asthma
Pneumothorax, pneumomediastinum, atelectasis, etc. It may occur in the acute episode of asthma, and it is easy to be complicated with heart failure, emphysema and bronchiectasis. Children with bronchial asthma can be diagnosed by the following laboratory tests.
1, blood routine examination. Some patients may have eosinophilia during the attack, but most of them are not obvious. If complicated with infection, the number of white blood cells may increase, and the proportion of classified neutrophils may increase.
2, sputum smear. More eosinophils can be seen, such as respiratory tract bacterial infection. Gram staining of sputum smear, cell culture and drug sensitivity test are helpful for the diagnosis and treatment of pathogenic bacteria.
3. Lung function examination. The pulmonary ventilation function in remission stage is mostly in the normal range. At the onset of asthma, due to the limitation of expiratory flow rate, it is characterized by forced expiratory volume in the first second (FEV 1), velocity in the first second (FEV 1/FVC%), maximum expiratory flow rate (MMER) and maximum expiratory flow rate (MEF 50% and MEF 75%) when expiratory vital capacity is 50% and 75%.
4. Blood gas analysis. When asthma attacks are severe, hypoxia may occur, and PaO2 _ 2 and SaO2 _ 2 will decrease. Because of hyperventilation, PaCO2 _ 2 will decrease and pH value will increase, showing respiratory alkalosis. Such as severe asthma, further development, severe airway obstruction, hypoxia and CO2 retention, PaCO2 _ 2 increase, showing respiratory acidosis. If hypoxia is obvious, it can be combined with metabolic acidosis.
5. chest x-ray examination. At the early stage of asthma attack, the transparency of both lungs increased, showing an over-inflated state; There was no obvious abnormality in remission period. If complicated with respiratory tract infection, increased lung texture and inflammatory infiltration shadow can be seen. At the same time, we should pay attention to complications such as atelectasis, pneumothorax or mediastinal emphysema.
6. Detection of specific allergens. Asthma patients are mostly accompanied by allergic reactions and are sensitive to a variety of allergens and irritants. The determination of allergic indicators combined with medical history is helpful to the etiological diagnosis of patients and to get rid of contact with allergic factors. However, allergic reactions should be prevented.
Treatment of bronchial asthma
1, inhaled.
Inhaled glucocorticoid is a long-term drug to control asthma, which has the advantages of strong local anti-inflammatory effect and less systemic adverse reactions. It usually needs long-term and standardized inhalation to play a preventive role.
In acute asthma attack, β2 receptor agonist should be inhaled first, then glucocorticoid should be inhaled. For children with seasonal asthma attacks, glucocorticoid can be inhaled continuously and regularly from 2 to 4 weeks before the expected attack. The maintenance dose of inhaled corticosteroids for children is 200-400μ g per day. Rinsing with clean water or choosing powder inhalers can reduce local adverse reactions including hoarseness, throat discomfort and oral candidiasis.
Step 2 take orally
At the time of acute attack, the patient was seriously ill and was treated with high-dose hormone inhalation. Short-term oral prednisone 1-7 days, daily dose 1-2 mg/kg (the total amount does not exceed 40mg), divided into 2-3 times. Glucocorticoid-dependent asthma can be taken every other morning, but long-term oral administration of prednisone or dexamethasone has great adverse reactions, especially in developing children, so long-term use should be avoided as far as possible.
3. Intravenous administration
For severe asthma attacks, intravenous medication should be given as soon as possible. The commonly used drugs are methylprednisolone 1-2 mg/kg or hydrocortisone succinate 5- 10 mg/kg, 2-3 times a day, generally used for a short time, and stopped taking drugs within 2-5 days. If glucocorticoid is used continuously for more than 10 days, it should not be stopped suddenly, but should be reduced to avoid recurrence.
What is good for bronchial asthma?
Dietary therapy for children with bronchial asthma;
1, Luffa Fengyi japonica rice porridge
Recipe ingredients: loofah 10 tablets, 2 pieces of egg film, 30 grams of japonica rice.
Production method: decoct the juice with egg membrane water, cook 1 bowl of japonica rice porridge, add loofah to cook, and add salt, monosodium glutamate and sesame oil to taste. Take it daily while it is hot 1 time.
Health tips: clearing away heat and resolving phlegm, relieving cough and asthma, and regulating spleen and stomach. It is suitable for patients with heat asthma, characterized by shortness of breath, wheezing in the throat, cough attack, yellow and sticky phlegm, upset and thirsty, red tongue, yellow and greasy fur and slippery pulse.
2. Steamed grapefruit chicken
Recipe ingredients: 1 green grapefruit, 1 chicken.
Production method: after the chicken is slaughtered, it is washed and cut into pieces for later use, and the top cover of the grapefruit is cut to remove the grapefruit pulp. Stuff chicken pieces into grapefruit, put them in a bowl with a lid, steam for about 3 hours, eat chicken and drink soup. Once a day, each time 1, for several days.
Health tip: This can relieve cough and increase nutrition. Indications: chronic asthma, weakness, emaciation, hunchback and hunchback.
Prevention of bronchial asthma
Asthmatic bronchitis usually begins in infancy (under 3 years old) and is often caused by various allergens (such as pollen, dust, animal hair, mites, bacteria, etc.). Allergens need to be isolated, and climate change and emotional excitement can also be induced, so keep a happy mood.
When a child is sick, parents should pay attention to respiratory isolation, reduce the chance of secondary bacterial infection, often change their positions and drink plenty of water to facilitate the discharge of respiratory secretions. In diet, it should be light, and don't eat too salty or too sweet food. Indoor air should be kept fresh and properly ventilated, but there should be no convection wind to prevent children from catching a cold again. After rehabilitation, you should take your children to public places as little as possible, pay attention to strengthening cold and warmth, and avoid asthma caused by external climate change again.
Avoid and control the inducing factors of asthma and reduce the recurrence. Make a medication plan for long-term management of asthma. Make a treatment plan for the attack period. Regular follow-up health care. Enhance physical fitness and disease resistance.
As long as we can persist in long-term treatment, most children's asthma can be controlled, and the recurrence can be reduced or even prevented.