| 摘要 |
<p>A prebubble detector is provided for an underwater drainage apparatus. A series of sensors and detectors are disposed along the small arm of the underwater seal in a drainage device and means is provided for detecting the least degree of negativity reached during each breathing cycle. This information is fed to a logic circuit, timer and display so that the physician can readily see what the least degree of negativity reached is and how long a period of time has elapsed since the least degree of negativity has not decreased. A continuing trend of the least degree of negativity toward zero would indicate an air leak in the pleural cavity whereas stability of the least degree of negativity would indicate no air leak in the pleural cavity.</p> |
