The vital capacity refers to the amount of gas exhaled by the maximum capacity after a maximum inhalation in an unrestricted time. This represents the maximum amount of functional activity of the lungs and is one of the important functional indicators reflecting the growth and development level of the human body. The National Student Health Standards for Physical Fitness requires that the vital capacity be a mandatory item for students in grades five and six of elementary school and junior high school, high school, and university. Lung capacity is affected by age, gender, length, and body surface area. Vital capacity = tidal volume + supplemental inspiratory volume + supplemental expiratory volume. Tidal volume refers to the amount of gas that is inhaled or exhaled during each breath.

Basic Information

Specialist classification: Respiratory examination classification: pulmonary function test

Applicable gender: whether men and women apply fasting: not fasting

Tips: Two days before the examination, all the drugs for bronchiectasis should be stopped, such as Shuchuanling, Bangfu, Meipuqing, aminophylline, Shufumei Lehui, Asami, Aichuan, etc. Otherwise it will affect the inspection result. Normal value

Male: 3.47L; Female: 2.44L.

Clinical significance

Abnormal results:

Reduce various lung parenchymal lesions, emphysema, pleural lesions, thoracic deformities, respiratory muscle weakness or paralysis. Note that the vital capacity is affected by age, gender, body length, body surface area, etc., so it should be judged by the percentage of predicted value as an indicator. The normal population is 100±20%, and <80% is a decrease.

Need to check the crowd:

People who need to undergo a physical examination, suspected pulmonary parenchymal lesions, emphysema, pleural lesions, thoracic deformities, respiratory muscle weakness or paralysis.

Low results may be diseases: talc dust lung, emphysema, asthma, obstructive emphysema, menstrual asthma considerations

Preparation before inspection:

Two days before the examination, all the drugs for bronchodilation should be stopped, such as Shuchuanling, Bangfu, Meipuqing, aminophylline, Shufumei Lehui, Asami, Aichuan, etc., otherwise it will affect test result.

Requirements for inspection:

1: To maintain hygiene, use a disposable blow.

2: When inhaling the machine after inhaling force, it should be carried out slowly and continuously without interruption.

Not suitable for people:

Regular inspection, there is no suitable for the crowd.

Inspection process

Take a deep breath and breathe slowly and continuously against the leak of the machine. Until you can no longer exhale.

Not suitable for the crowd

Nothing is suitable for the crowd.

Adverse reactions and risks

No complications or harm.