Catheter Balloon-trauma: Design, Development, and Ex-vivo Studies Using Intact Human Penis Specimens

Abstract

To present a novel urethral catheter design with a pilot balloon to reduce intraurethral retention balloon inflation pressures and to provide a visual alert during catheter placement. We manufactured our pilot balloon prototype from both molded and extruded silicone components. Various pilot balloon thicknesses were tested in order to determine the ideal compliance. We studied the filling pressures of the retention balloon of our prototype in a mechanical urethral model. The prototype catheter was then tested in ex-vivo human penis specimens obtained from gender affirming surgery and changes in the size of the retention balloon were measured under fluoroscopy. The thickness of the pilot balloon was directly related to the inflation pressure of the retention balloon in the mechanical urethral model. The thickness chosen for the pilot balloon in our prototype was based on a retention balloon pressure of 70 kPa. In the ex-vivo human penis model, the presence of the pilot balloon resulted in a 40% reduction in the cross-sectional area of the retention balloon compared to a standard urinary catheter. The prototype urinary catheter appears to decrease the filling pressure and size of an improperly positioned retention balloon inside a urethra. This can potentially reduce the risk of iatrogenic urethral catheter injuries. In addition, the prototype urinary catheter may act as a visual warning sign for the healthcare practitioner.