| 摘要 |
A surgical device is disclosed which enables selective ventilation of the lungs of a patient. The device is inserted into the patient's respiratory passages and is employed in conjunction with a conventional breathing circuit which allows ventilation of either lung alone or both lungs simultaneously by pumping life supporting gases, typically including anesthetic agents, through the tube during surgery. The device comprises an elongated flexible tube split at its proximal end into left and right tubular extensions and having a curved distal end adapted to be inserted via the patient's mouth through the trachea into the left main stem bronchus. Inflatable cuffs surrounding the tube permit the lungs to be isolated from each other and from the atmosphere. The interior of the tube is divided into left and right passageways by a septum, which is arranged such that the left lung can be ventilated through the left tubular extension, the left passageway and an orifice at the distal end of the tube, and the right lung can be ventilated through the right tubular extension, the right passageway and an orifice in the side of the tube between the cuffs. The septum comprises a thin flexible membrane having a transverse dimension roughly equal to one-half the circumference of the tube's interior surface, whereby externally applied differential pressures will cause the membrane to position itself along one side of the tube to permit utilization of virtually the entire cross-sectional area within the tube for ventilating the lung corresponding to the higher of the two externally applied pressures. Both lungs can be simultaneously ventilated using equal externally applied pressures which cause the septum membrane to return to a center position, thus providing half the cross-sectional area for each of the two passageways. |
