A pleural manometry catheter comprises two tubes and a pressure transducer. The first tube provides a first flow path from the pleural cavity to the pressure transducer. The second tube provides a second flow path from the pleural cavity such that fluid can be drained from the pleural cavity. The pressure transducer detects real-time changes in the fluid pressure of the first flow path, such that when in use, fluid is drained from the pleural cavity along the second tube, the sensor in communication with the first tube detects a concomitant drop in fluid pressure in the fluid in the first tube.