Respiratory failure, if categorized by its cause, can be divided into pump failure and lung failure. Pump failure refers to the failure of the respiratory pump, which comprises the central nervous system that drives or regulates respiratory movement, the peripheral nervous system, neuromuscular tissues, and the thoracic cage, collectively known as the respiratory pump. Respiratory failure caused by dysfunction of these components is called pump failure. Another type is lung failure, which results from airway obstruction, pulmonary tissue and vascular pathology, and is termed lung failure. Lung failure can lead to type I or type II respiratory failure, whereas pump failure typically presents as type II respiratory failure.