Passive drainage is accomplished by gravity or capillary action. Drainage is further facilitated by transient increases in intra-abdominal pressure, as with coughing. Passive surgical drains include Penrose, Foley, Malecot, and Word catheters.
Active drainage is accomplished by suction from a simple bulb device or a suction pump.
These systems may be closed, like the Hemovac and Jackson-Pratt drains. Examine the fluid for color, odor and volume. Also examine the tube for clots or other obstructing material. Increased bloody drainage can be due to vessel leakage and may be caused by catheter erosion into a vessel. Document rate of bleeding every 30-60 minutes.