Asthma Asthma, also known as bronchial asthma, is a chronic airway disease characterized primarily by chronic inflammatory reactions in the airways. Clinically, it manifests as recurrent wheezing, shortness of breath, chest tightness, or coughing, often worsening or occurring at night and in the early morning. Most patients can experience relief either spontaneously or through treatment.

Recurrent wheezing, shortness of breath, chest tightness, or coughing

Genetic and environmental factors are the main causes of asthma

Asthma is difficult to cure and generally requires medication for treatment

With standardized treatment, 80% of patients can achieve clinical control

Asthma, also known as bronchial asthma, is a chronic airway disease characterized primarily by chronic inflammatory reactions in the airways. Clinical manifestations include recurrent wheezing, shortness of breath, chest tightness, or coughing, which often occur or worsen at night and in the early morning. Most patients can resolve symptoms on their own or through treatment.

Exercise-induced asthma

Caused by physical activity, with a direct relationship to the type, duration, amount, and intensity of exercise. The attacks are acute and brief, and most can resolve on their own.

Drug-induced asthma

Caused by the use of certain medications, such as aspirin, beta-blockers, etc.

Occupational asthma

Caused by occupational asthmagens such as polyurethane foam, synthetic fibers, adhesives, etc. Symptoms often occur during or a few hours after work, with shortness of breath, chest tightness, coughing, and accompanying rhinitis and/or conjunctivitis. Symptoms usually alleviate after leaving the workplace.

Allergic asthma

Often caused by allergens acting on allergic individuals, leading to allergic diseases (such as allergic rhinitis, etc.), manifested as sneezing, runny nose, coughing, chest tightness, wheezing, and even difficulty breathing.

Genetic factors

Asthma has a polygenic inheritance tendency, with a certain familial aggregation phenomenon, meaning the closer the blood relationship, the higher the incidence of the disease. However, the onset of asthma is often the result of the combined action of multiple genes and exogenous factors.

Environmental factors

Pathogenic factors such as indoor allergens (pets, cockroaches, etc.), outdoor allergens (pollen, grass pollen, etc.), occupational allergens (paints, reactive dyes, etc.), food (fish, shrimp, eggs, milk, etc.), drugs (aspirin, antibiotics, etc.), and other stimuli can trigger asthma.

Non-pathogenic factors, such as air pollution, smoking, exercise, and obesity, may also trigger asthma.

Climate factors

Including air pressure, temperature, wind force, humidity, etc., changes in which may trigger asthma.

Exercise factors

In clinical practice, most asthma or allergic rhinitis patients often experience asthma attacks or symptoms of coughing and chest tightness after exercise. Activities such as short-distance running, long-distance running, and mountain climbing are particularly likely to trigger mild or stable asthma attacks, while the impact of swimming is relatively mild, making it more suitable for asthma patients.

Respiratory infections

Such as viral infections, mycoplasma infections, and bacterial infections, are all prone to trigger asthma attacks or exacerbations.

Psychological and emotional factors

Can significantly affect the onset and severity of asthma.

Deficiency of trace elements

Iron and zinc deficiencies are relatively common, and these deficiencies can lead to decreased immune function, triggering asthma.

Drug factors

Drug-induced asthma attacks can be specific or nonspecific, with the former most commonly associated with biological product allergies and the latter often occurring with sympathetic nerve blockade drugs such as propranolol and drugs that enhance parasympathetic nerve activity.

Typically, there are recurrent episodes of wheezing, shortness of breath, chest tightness, or coughing. Severe cases can lead to rapid onset of breathlessness and hypoxemia.

Prodromal symptoms

Before an attack, there are often prodromal symptoms such as nasal congestion, sneezing, and itchy eyes.

Symptoms during acute asthma attacks

Mild

Shortness of breath when walking or climbing stairs, possible anxiety, slight increase in respiratory rate, and scattered wheezing sounds may be heard.

Moderate

Even slight activity leads to shortness of breath, speech is frequently interrupted, anxiety is present, respiratory rate is increased, and there may be a three-depression sign (referring to a noticeable depression in the suprasternal notch, supraclavicular fossa, and intercostal space during inhalation), loud, diffuse wheezing sounds are heard, and the heart rate is increased.

Severe

Shortness of breath at rest, sitting upright to breathe, only able to express single words, often anxious and restless, profuse sweating, respiratory rate >30 times/min, often exhibiting the three-depression sign, loud, diffuse wheezing sounds are heard, and heart rate is often >120 times/min.

Critical

The patient cannot speak, is drowsy or confused, wheezing diminishes or disappears, and the pulse rate becomes slow or irregular.

Chest X-ray

In addition to a general chest X-ray, sometimes a chest CT scan is needed, which can help in the diagnosis and differentiation of asthma and in estimating the severity of asthma.

Pulmonary function tests

Bronchial provocation tests and bronchodilation tests help establish the diagnosis of asthma and are the most commonly used indicators for objectively judging the severity of asthma. Bronchodilation tests also help estimate the potential efficacy of β2-agonists, providing reference for drug selection.

Fractional exhaled nitric oxide (FeNO) testing

Can serve as an indicator for assessing the initiation of inhaled corticosteroid therapy and is helpful in managing asthma during pregnancy.

Blood gas analysis

The results, especially parameters such as arterial oxygen pressure (PaO2), oxygen saturation (SaO2), and carbon dioxide pressure (PaCO2), can estimate the severity of asthma during acute attacks.

Sputum eosinophil count

Is one of the indicators for evaluating airway inflammation in asthma and is a sensitive indicator for assessing the responsiveness to corticosteroid treatment.

Allergen testing

Identifying allergens can help prevent recurrent asthma attacks.

Chronic bronchitis and chronic obstructive pulmonary disease (COPD)

The onset of the disease is mostly in middle-aged and elderly people, most of whom have a long history of cough and sputum, and the symptoms worsen during cold seasons. A person can be diagnosed with chronic bronchitis if they have been coughing for more than three months continuously each year for two consecutive years, and other causes of cough and sputum have been ruled out.

If there is persistent airflow limitation (FEV1/FVC <70% after using bronchodilators during the stable period), it is diagnosed as chronic obstructive pulmonary disease (COPD).

Lung cancer

The etiology is complex and not yet fully understood, generally associated with long-term smoking, air pollution, and indoor environmental pollutants (cooking fumes), among others. The symptoms of cough and wheezing caused by lung cancer often gradually worsen and may include hemoptysis or small amounts of blood in the sputum, with ineffective response to asthma medications.

Pleural effusion

Often caused by tuberculosis, differentiation from asthma can be achieved through chest radiography and X-rays. Patients with tuberculous pleurisy generally present with symptoms such as fever, night sweats, and chest pain.

Spontaneous pneumothorax

Sudden sensation of chest pressure, mostly unilateral, accompanied by inspiratory dyspnea, and ineffective response to asthma medications.

Pulmonary embolism

Mostly associated with blood stasis, vascular endothelial injury, etc., it presents with significant chest tightness, dyspnea, and difficulty breathing, which can make the patient restless and intolerant. Blood gas analysis shows significant hypoxemia, but generally no wheezing is heard in the lungs, and the response to asthma medications is ineffective.

Mild Acute Asthma Attacks

Inhaled therapy with salbutamol or terbutaline aerosol is effective and usually takes effect within minutes, or oral β2-agonists can be used.

Moderate Acute Asthma Attacks

Partial improvement in symptoms after inhaling bronchodilators often requires combined use of inhaled beclomethasone or budesonide aerosols.

Patients with moderate acute asthma attacks often experience nocturnal asthma attacks and worsened symptoms, and often require the use of long-acting sustained-release theophylline and other drugs to effectively prevent nocturnal asthma attacks.

Severe Acute Asthma Attacks

In this case, the effects of inhaled β2-agonists and corticosteroids are not obvious, and emergency hospitalization is often required.

Perioperative Asthma Management

Refers to patients with a history of asthma who also have other diseases requiring surgical treatment or exploration, and require asthma assessment to avoid factors that may trigger asthma.

Preoperative preparations: Asthma assessment should be conducted at least 1 week before surgery. Routine lung function tests are recommended. For elective surgery, good asthma control should be achieved before the procedure; for emergency surgery, the pros and cons must be weighed.

Intraoperative management: Neuromuscular blocking agents are the most common drugs that induce allergic reactions, such as mivacurium.

Postoperative management: Good postoperative pain management, enhanced respiratory training, and control of gastroesophageal reflux may help reduce the risk of acute asthma attacks.

Bronchial Thermoplasty

Bronchial thermoplasty is a non-pharmacological treatment for asthma. It uses a bronchial thermoplasty system to deliver heat energy to the airway wall, causing smooth muscle in the bronchus to dissolve and undergo coagulative necrosis, preventing excessive bronchial constriction in asthmatic patients when exposed to external stimuli, thereby reducing asthma attacks.

For patients with severe or refractory asthma who cannot be controlled even with maximum doses of multiple medications, bronchial thermoplasty may be considered. Although this procedure does not cure asthma, it can significantly reduce acute asthma attacks and improve asthma control.

Emphysema and Cor Pulmonale

If airflow obstruction is not controlled for a long time, the residual lung volume increases, leading to destruction of the alveolar structure and the formation of emphysema. Further development leads to compression of the blood vessels around the alveoli, increased pulmonary circulation resistance, and the formation of chronic pulmonary hypertension, eventually leading to right heart failure and chronic cor pulmonale.

Respiratory Failure

Typically, it is type II respiratory failure, and during severe asthma attacks, it is type I respiratory failure.

Respiratory Arrest

Refers to the serious complication of sudden cessation of breathing in asthma patients, often occurring when the patient coughs or eats, and can also occur after minimal physical activity.

Pneumothorax and Mediastinal Emphysema

Due to severe lung structural damage, patients are prone to pneumothorax and mediastinal emphysema when exerting force or lifting heavy objects. Lung re-expansion should be achieved as soon as possible.

Allergic Bronchopulmonary Aspergillosis

An allergic reaction to Aspergillus antigens, manifested as fatigue, weight loss, cough, night sweats, clubbing, and the appearance of brownish small pieces in sputum, with Aspergillus cultivation showing the presence of Aspergillus fumigatus, and chest X-rays showing migratory lung infiltrates.

Arrhythmias and Shock

Severe hypoxia, excessive use of aminophylline, excessive use of isoproterenol, and rapid injection rates can all cause arrhythmias and shock.

Thoracic Deformities

Asthma patients, especially those who develop the disease at a young age or have repeated attacks, often develop thoracic deformities, the most common being barrel chest, pectus carinatum, and rib cage flaring, which can significantly affect respiratory function.

Avoid allergens in the air: Dust mites are the culprits for some types of asthma. Use ventilated bed covers to encase mattresses, wrap pillows, and wash pillowcases weekly, and avoid using carpets, among other measures.

Encourage family members and patients to avoid contact with allergens from pets, such as cats and dogs.

Avoid allergenic foods: such as shrimp and crab.

Avoid air pollution: Avoid indoor irritants such as tobacco and household sprays.

Patients should learn to use inhalation devices correctly, and family members should also be familiar with their use.