Balloon-tipped catheter for measuring urethral pressures.
BACKGROUND
Better methods are needed for recording urethral function for complex urologic problems involving the bladder, urethra, and pelvic floor.


OBJECTIVE
To evaluate a balloon catheter for recording urethral pressure and function using bench-top testing and evaluation in an animal model.


METHODS
Balloon pressure-recording methods included slightly inflating the balloon with water and placing the pressure transducer on the distal end of the catheter. For bench-top testing, manual procedures and a silastic tube with a restriction were used. In 3 anesthetized dogs, pressure recorded from the skeletal urethral sphincter was induced with electrical stimulation of the sphincter. Anal sphincter pressure was also recorded.


RESULTS
Bench-top testing showed good pressure recordings, including a confined peak at the tube restriction. Animal tests showed urethral pressure records with rapid responses when electrical stimulation was applied. Peak pressure at the urethral skeletal sphincter was 55.7 +/- 15 cmH2O, which was significantly higher than the peak pressure recorded 2 cm distally in the proximal urethra (3.3 +/- 2.3 cmH2O). Peak anal pressures were smaller and unchanged for the 2 stimulations.


CONCLUSIONS
Balloon-pressure recordings showed rapid responses that were adequate for the tests conducted. In the animal model, high-pressure contractions specific to the skeletal urethral sphincter were shown. Balloon-tipped catheters warrant further investigation and may have applications for the evaluation of detrusor-sphincter dyssynergia after spinal cord injury or for stress urinary incontinence.
Walter
James S
JS
Hines VA Hospital (151), Research Service, Hines, IL 60141, USA. james.walter@va.gov
Wheeler
John S
JS
Wang
Xiaoli
X
Wurster
Robert D
RD
D000818:Animals; D002404:Catheterization / Q000379:methods*; D004285:Dogs; D005260:Female; D023421:Models, Animal; D011312:Pressure; D014160:Transducers, Pressure; D014521:Urethra / Q000503:physiopathology*