What is the cause of death for respiratory failure?

Lack of oxygen: Respiratory failure means that the respiratory system which is made up of the oral aiway, trachea, bronchus and lungs and also involves the diaphragm and the breathing (respiratory) center in the brain (stem). If any of these parts fail or become impaired then the body cannot deliver enough o2 to the brain or heart and death ensues.

See below: There are two types of respiratory failure - hypoxic where the body does not get enough oxygen, and hypercapneic, where the lungs cannot wash out the carbon dioxide. Either one can cause death. Usually, we can give supplemental oxygen or help with various machines to blow off the co2 but if the underlying lung disease cannot be reversed, that results in death.