文档介绍：Respiratory Failure

Respiratory failure, whether acute or chronic, is a frequently faced problem and a major cause of death in our country.
For example, mortality from COPD, which ends in death from respiratory failure, continues to increase.
More than 70% of the deaths in patients with pneumonia are attributed to respiratory failure.

Respiratory failure affects the lung’s ability to maintain arterial oxygenation or carbon dioxide(CO2) elimination.
It is defined as a condition in which this gas exchange deteriorates below the usual level, so that arterial oxygen tension decreases, with or without an abnormal rise in arterial carbon dioxide tension.

acute respiratory failure
chronic respiratory failure
Type Ⅰrespiratory failure
Type Ⅱrespiratory failure
Central respiratory failure
peripheral respiratory failure
Classification :Type Ⅰrespiratory failure
Type Ⅰrespiratory failure is also called hypoxic respiratory failure, which means that severely reduces arterial oxygen tension(PaO2<60mmHg), CO2 retention is not exist.
Classification : Type Ⅱrespiratory failure
Type Ⅱrespiratory failure is also meant that hypercapnic-hypoxic respiratory failure.
Arterial blood gas values shows that arterial carbon dioxide tension is more than 50 mmHg and arterial oxygen tension is less than 60 mmHg
Type Ⅱrespiratory is mainly caused by hypoventilation.
chronic respiratory failure
Pathogenesis
we have known that the lungs’ ability is gas exchange. The gas exchange involves not only oxygenation but also carbon dioxide elimination.
Pathogenesis
Respiratory failure is mainly associated with pulmonary gas exchange and pulmonary ventilation.
1. pulmonary gas exchange is mainly determined by ventilation-perfusion(V/Q) ratios and diffuse ability
V/Q mismatch: An effective lung gas exchange needs not only sufficient lung ventilation and lung blood volumes but also an adequate V/Q ratios.
Usually, the volume of ventilation is 4