Urinary catheter capable of repeated on-demand removal of infectious biofilms via active deformation

Abstract

Biofilm removal from biomaterials is of fundamental importance, and is especially relevant when considering the problematic and deleterious impact of biofilm infections on the inner surfaces of urinary catheters. Catheter-associated urinary tract infections are the most common cause of hospital-acquired infections and there are over 30 million Foley urinary catheters used annually in the USA. In this paper, we present the design and optimization of urinary catheter prototypes capable of on-demand removal of biofilms from the inner luminal surface of catheters. The urinary catheters utilize 4 intra-wall inflation lumens that are pressure-actuated to generate region-selective strains in the elastomeric urine lumen, and thereby remove overlying biofilms. A combination of finite-element modeling and prototype fabrication was used to optimize the catheter design to generate greater than 30% strain in the majority of the luminal surface when subjected to pressure. The catheter prototypes are able to remove greater than 80% of a mixed community biofilm of Proteus mirabilis and Escherichia coli on-demand, and furthermore are able to remove the biofilm repeatedly. Additionally, experiments with the prototypes demonstrate that biofilm debonding can be achieved upon application of both tensile and compressive strains in the inner surface of the catheter. The fouling-release catheter offers the potential for a non-biologic, non-antibiotic method to remove biofilms and thereby for impacting the thus far intractable problem of catheter-associated infections.

Nanoscience‐Based Strategies to Engineer Antimicrobial Surfaces

“…Based on this concept, researchers have used various external stimuli, including electrical, mechanical, and pneumatic, to induce dynamic surface deformations that are able to detach both biofilms and macrofouling organisms. [85] Such dynamic surfaces are active after biofilm formation or bacterial attachment rather than by directly killing the cells or inhibiting bacterial growth. [83] Recently, this approach has been applied to implant devices by introducing two inflation lumens into the tube walls of the silicone elastomer of a urinary catheter.…”

Review of Catheter-Associated Urinary Tract Infections and In Vitro Urinary Tract Models

“…Another study by Levering et al [ 66 ] developed a novel ID design that aimed to disrupt and dislodge biofilms from the catheter's inner drainage lumen. Their catheter was designed to have inflation lumens which run the length of the catheter in between the urine drainage lumen and the outer catheter wall [ 66 ].…”

“…Another study by Levering et al [ 66 ] developed a novel ID design that aimed to disrupt and dislodge biofilms from the catheter's inner drainage lumen. Their catheter was designed to have inflation lumens which run the length of the catheter in between the urine drainage lumen and the outer catheter wall [ 66 ]. When inflated, they found that the pressure exerted by the inflation lumens was sufficient to dislodge crystalline biofilms from the inner luminal surface, breaking them apart, so the remnants could then be flushed out by the flow of the patient's urine [ 66 ].…”

Innovations in indwelling urethral catheterisation

“…The catheter design features four additional inflation channels running the length of the catheter, within its wall and parallel to its lumen. Pushing liquid through the four channels strains the catheter surface, which has been shown in vitro to mechanically dislodge 90% of biofilm from the drainage lumen . Another exciting innovation under development is a flexible impedance sensor that integrates biofilm detection and treatment .…”