Mechanical Characteristics of Male Urethral Catheterization: Simulator and Cadaveric Donor Study

Abstract

Catheter-associated urinary tract infections (CAUTI) is among the most common hospital acquired infection [1], while medical students placing catheters could increase CAUTI risk four times [2]. Therefore, a better understanding of the catheter insertion mechanical characteristics is needed to develop more realistic simulators for accurate clinical training. A custom-made Catheter Insertion Force Assessment Tool (+/- 0.25N absolute accuracy) and Position Acquisition System were used in male urethral catheterization studies on benchtop simulators (n=4) and cadaveric donors (n=5) to quantitatively examine the insertion force and 3D motion. Displacement-dependent effects resembling tissue stiffness appeared to dominate the force profile over rate-dependent effects such as viscous friction. In cadaveric studies, the average prostate region force was found to be higher than non-prostate region force. Average catheterization forces in simulators (8.1N) were roughly 45 percent higher than in donors (5.6N) when considering all data per insertion segment falling within 98 percentiles to diminish outlier effects.