Instillation Drain Configuration Influences the Completeness of Fluid Dispersion. Bates M, Risselada M. Purdue University Veterinary Teaching Hospital, West Lafayette, IN.
Instillation of medications in a closed wound may facilitate ongoing local therapy after wound closure. Use of an active suction drain to retrieve instillation fluid, rather than a vacuum-assisted closure device, may improve accessibility to this treatment, but interference of the drain with the catheter has not been evaluated. The objective of this study was to describe the influence of drain placement on distribution of instillation fluid within a closed space. We hypothesized that the configuration of instillation catheter placement would influence fluid dispersion. A 10 cm2 square model was constructed using plastic sheeting on a plexiglass sheet, and an instillation catheter and active suction drain were secured in four configurations: parallel, opposite, perpendicular, and diagonal. Configuration was significantly associated with mean percentage surface area covered by fluid (P < 0.0001): surface area covered after parallel placement (52% ± 3.3%) was significantly less than opposite (98% ± 1.4%), perpendicular (99% ± 1.4%), or diagonal (94% ± 4.9%) (P < 0.001). Only mechanical interference of drain placement was assessed; fluid recovery was not yet evaluated and is part two of this project. Additional variables regarding the effect of shape and size of the wound, the position and orientation of the wound on the patient, and presence of clefts and tunnels were similarly not introduced in order to solely investigate drain placement but will play a role in the live animal. Instillation catheters should not be placed parallel to a suction drain in a closed space as the fluid will not cover the full surface.