The amount of residual gas is the amount of gas remaining in the lungs after deep hearing. It reflects the static expansion of alveoli and stabilizes the partial pressure of alveolar gas, which reduces the influence of intermittent ventilation on the partial pressure of air in the alveoli. The amount of residual gas and functional residual capacity of restrictive diseases decreased, and obstructive diseases increased. The normal adult residual capacity is 1000~1500ml. The amount of residual gas in patients with bronchial asthma and emphysema increases.

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 1.38 ± 0.63L; female 1.30 ± 0.47L.

Clinical significance

Increase emphysema, small airway premature closure. Residual gas volume increased significantly, suggesting chronic obstructive ventilatory disorders, such as emphysema, pulmonary heart disease.

High results may be diseases: obstructive emphysema, emphysema, pulmonary heart disease precautions

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.

Inspection process

When the pulmonary function instrument measures FRCHe, the subject takes a sitting position, adds a nose clip, and the mouthpiece is in a breathing balance, and then the patient is turned to a spirometer, and the three-way valve is turned to the spirometer to start the measurement. During repeated breathing, according to the oxygen consumption, the appropriate amount of pure oxygen was automatically compensated, the baseline of breathing was maintained, and the inspiratory vital capacity and expiratory lung capacity were each performed once after 7 minutes of calm breathing, and the measurement was terminated at the end of calming expiration. The result of the measurement is automatically calculated by the computer.

Not suitable for the crowd

If you have a serious cardiopulmonary disease, you should consult your doctor before doing this check.

Adverse reactions and risks

Generally no complications and harm.