As the weather turns cold and the peak of respiratory diseases is coming, knowing some tips related to pulmonary function tests can reduce unnecessary worries and doubts of patients, make the communication between doctors and patients smooth, reduce the examination time and improve the work efficiency.

We know that the lungs have a variety of functions, such as respiratory function, endocrine function, metabolic function, etc., but mainly respiratory function, clinically referred to as the lung function test is essentially the determination of respiratory function, generally refers to the lungs of the ventilation and gas exchange function measurement.

Lung function test is a routine examination of the respiratory system, mainly used to detect the degree of respiratory patency, lung volume size, etc. The results of the examination have an important clinical value for lung and airway pathology, disease prognosis, assessment of drug efficacy and other aspects.

There are many lung function test items, different items use different instruments and equipment, and the test methods are not exactly the same. Generally when doing pulmonary function tests, there will be a professional doctor to guide.

Lung function test includes two aspects

Lung function tests have two main clinical applications:

First, in terms of disease diagnosis and treatment, the results of pulmonary function tests can be utilized to assess the respiratory function of the subject and clarify whether the respiratory function is impaired, the degree of impairment, and the type of impairment. It is commonly used to assist in the diagnosis of chronic obstructive pulmonary disease, bronchial asthma, emphysema, pulmonary fibrosis, pulmonary vascular lesions, pneumoconiosis, tuberculosis and other diseases;

The second is the application in surgery, which mainly includes the selection of surgical indications, clarification of whether the patient can tolerate general anesthesia, whether he can tolerate surgery, assessment of risks during the surgical process and perioperative period, occurrence and prevention of possible complications after surgery, assessment of quality of life after surgery, and how to carry out post-surgical rehabilitation.

Pulmonary function tests are an important method of assessing the indications for surgery, especially cardiothoracic and abdominal surgery, and the choice of maintenance measures during the perioperative period.

How is the test performed?

During the pulmonary function test, the subject is required to clamp the nose and breathe through the mouth. During the test, the subject is required to follow the doctor's instructions strictly, breathing calmly or slowly, and sometimes quickly as required, and for as long as the doctor requires. Only when the subject fully understands the purpose and requirements of the test, and actually follows the requirements, can the objectivity of the test results be guaranteed.

What kind of preparation does the subject need before the test?

Strenuous exercise should be avoided 2 hours before the test. It is recommended that the subject sit still for 15 minutes before the test and wait until his/her breathing stabilizes before performing the pulmonary function test;

If the patient has difficulty in breathing before the test, he/she should inform the doctor in time, at this time the patient can not perform the bronchial stimulation test;

Before the examination, the patient can first carry out "blowing" practice, you can pinch the nose and then practice blowing candles, so as to improve the success rate of the examination and reduce the examination time.

Are there any contraindications for pulmonary function tests?

Lung function tests should not be performed in the following situations:

Pneumothorax and within 1 month after healing of pneumothorax, patients with severe pulmonary alveoli, respiratory failure and tracheotomy;

Severe cardiac insufficiency, thoracoabdominal aortic aneurysm, hypertension (e.g., systolic blood pressure greater than 200 mmHg, diastolic blood pressure greater than 100 mmHg), cardiovascular diseases such as recent rib fracture, and patients with recent myocardial infarction and pulmonary embolism;

Patients with infectious diseases such as open tuberculosis, active chronic hepatitis, and positive new crown nucleic acid test;

Patients who are unable to cooperate with the examination due to cerebrovascular accidents, cerebral palsy, and impaired consciousness;

Patients with hemoptysis within 2 weeks;

People with high fever, severe cough, and extreme debility are temporarily unable to undergo pulmonary function tests;

Those who have had lung biopsy or lung endoscopy on the day of pulmonary function test.

Lung function tests should be performed with caution in the following cases

Pregnant women, patients with severe hernia, hemorrhoids and severe uterine prolapse and other diseases that may be aggravated when blowing up with force; people with easily dislocated temporomandibular joints; people with perforated tympanic membrane; and people with respiratory tract infections within 4 weeks.

How long will it take to see the test report after the lung function test?

Generally 0.5-4 hours after the test results report.

Friendly reminder:

It is recommended to observe for 15-30 minutes after the bronchial provocation test without any discomfort before leaving.