Influence of 4 drain configurations on fluid dispersal and retrieval in an instillation model

Abstract

To describe and compare the pattern of fluid dispersal and retrieval in a novel instillation therapy system. In vitro experimental study. A 10 cm2 square model was constructed using plastic sheeting secured to plexiglass, with a wound infusion catheter and Jackson-Pratt (JP) active suction drain positioned in 4 configurations: parallel, perpendicular, diagonal, and opposite. Fluid was instilled using the wound infusion catheter, allowed to dwell for 10 min, and retrieved using the JP drain. Two surface area calculations were made using imaging software: coloration with diluted methylene blue (MB) on photos, and filling with diluted contrast on fluoroscopic images. Fluid retrieval was recorded. Statistical analysis was performed using a mixed-effects linear model (p < .05). Configuration influenced fluid dispersion within the model (p=.0001); the diagonal configuration had the greatest surface area coverage (mean ± SD; 94.5 ± 2.4%) and the parallel configuration had the lowest surface area coverage (60.2 ± 2.9%). A dwell period increased fluid dispersal by an average of 4.0 ± 0.8% (p < .0001). Fluid retrieval exceeded 16.7 ± 1.5 mL (83.5 ± 7.5% volume instilled) for all configurations and was 0.5 ± 0.1 mL (2.5 ± 0.5% volume instilled) greater for MB than contrast agent (p < .0001). Perpendicular or diagonal configurations and low-viscosity fluid maximized fluid dispersion and retrieval. Wound instillation therapy involves delivering lavage fluid or medications to a closed wound space. This is feasible using a wound-infusion catheter and active suction drain. Configuration should be considered to optimize fluid dispersal and retrieval when planning instillation therapy.