A collateral ventilation bypass trap system directly linked with a
patient's lung or lungs may be utilized to increase the expiratory flow
from the diseased lung or lungs, thereby treating another aspect of
chronic obstructive pulmonary disease. The system includes a trap, a
filter/one-way valve and an air carrying conduit. In various embodiments,
the system may be intrathoracic, extrathoracic or a combination thereof.