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.