US Patent 7125402 Surgical drain

An improved surgical drain tube 10 having an internal passageway 12, a plurality of portions 14 of the external wall of the tube extending outwardly and being arranged in opposing pairs, the walls of the outwardly extending portions forming the sidewalls 14A, 14B, 16 of external channels 18 that run longitudinally along the length of the tube, and crossholes 20 positioned on the sidewalls of the outwardly extending portions 14 that provide for fluid flow from the channel 18 into the internal passageway 12 of the tube.