<unk>  (CV) is a back-up system of alveolar ventilation that can bypass the normal route of airflow when airways are restricted or obstructed. The pathways involved include those between adjacent alveoli (pores of Kohn), between bronchioles and alveoli (canals of Lambert), and those between bronchioles (channels of Martin).<unk>  also serves to modulate imbalances in ventilation and perfusion a feature of many diseases. The pathways are altered in lung diseases particularly asthma, and emphysema. A similar functional pattern of<unk> isation is seen in the circulatory system of the heart. Interlobar<unk>  has also been noted and is a major unwanted factor in the consideration of lung volume reduction surgery and some lung volume reduction procedures.
Collateral ventilation
Open lung ventilation
Negative pressure ventilator
Inverse ratio ventilation
Pressure support ventilation
Artificial ventilation
Mechanical ventilation
Prone ventilation