Development of a more clinically relevant bladder and urethral model for catheter testing

Area of Science:

• Biomedical Engineering
• Medical Device Design
• Urology

Background:

• Current rigid funnel models lack physiological relevance for bladder and urethral simulation.
• Existing catheter testing standards do not adequately address risks like urethral injury during removal with a filled balloon.

Purpose of the Study:

• To develop and validate a flexible, physiologically representative bladder and urethral model for improved catheter evaluation.
• To assess the feasibility of testing catheter retention and extraction characteristics using advanced materials and methods.

Main Methods:

• Designed a flexible elastomer bladder floor and urethral model.
• Conducted static and impact force tests, measuring internal retention balloon pressure.
• Validated the model by measuring urethral dilation and balloon pressure under traction and deflation.

Main Results:

• The flexible model successfully held a Foley catheter under static loads up to 0.7 kg.
• Impact forces from dropped weights dislodged the catheter, highlighting a critical failure point.
• Feasibility of measuring urethral dilation and balloon pressure was confirmed.

Conclusions:

• The developed flexible model provides a more realistic simulation of the bladder and urethra than current industry standards.
• This model enables better assessment of catheter retention and extraction, crucial for preventing urethral injury.
• The improved testing protocol can facilitate the design of safer urethral catheters.