Lung function classification standard

Everyone has two lobes of the lung in their body. The lungs are very important to us on both sides of the heart. They are mainly used to help our respiratory system and complete the function of breathing. If there is a problem with our lungs, we will not only cough, but also feel difficulty breathing, because the lungs not only help us breathe, but also help us breathe smoothly. So how many levels are there in lung function?

Five-level lung function classification

The five-level lung function classification system is mainly:

Level 1: Basically normal, maximum ventilation and vital capacity are close to normal, or within the normal range, and the minimum ventilation function is normal.

Level 2: Slight decrease, with the estimated maximum ventilation volume only reduced by 20% to 25%, slight hyperventilation, normal ventilation function, and no shortness of breath or decreased exercise endurance during general exercise.

Grade 3: Significant decrease, the estimated maximum ventilation volume may be reduced by 50% to 60%, hyperventilation is more obvious, hypoxia symptoms may or may not be present, carbon dioxide is slightly increased or normal, pH is high or normal, shortness of breath after activity, and no state at rest.

Grade 4: Severe damage, the estimated maximum ventilation volume may be reduced by 70% to 80%.

Grade 5: Respiratory failure, the maximum decrease in predicted maximum ventilation volume is greater than 80%.

Pathophysiological characteristics of COPD

1. In the early stage, small airway lesions (<2mm) are the main disease, which gradually affect the large airways.

2. The early symptoms are difficulty in exhaling, and in the late stage, both exhaling and inhaling are difficult.

3. Obstructive ventilation dysfunction in the early stage and mixed ventilation dysfunction in the late stage.

4. The breathing pattern is deep and slow in the early stage and shallow and fast in the late stage.