ACCESSIBLE INCONTINENCE DEVICE Arin Ellingson, Jon Sass, Ben Schoepke, David Schurter RERC –AMI National Design Competition Advisor: Mitchell Tyler

Outline  Review of project background  What we’ve done so far  Initial working prototype  Accessibility features  What we’re working on  New valve design  Testing protocol for validation and usability  Filtering bladder pressure signal

Urinary Incontinence  Urinary incontinence is the loss of bladder control  Affects >10 million people in the US, especially the elderly and disabled  $36 billion industry annually  Associated with diabetes, multiple sclerosis, Parkinson’s disease, stroke, spinal injury and others

Design Requirements  Allow voluntary emptying of the bladder  Prevent undesired urine flow  Provide an indication of bladder status  Remain indwelling for up to 30 days with no adverse tissue reaction or material degradation  Be easily used by a patient with disabilities

Work to date  Completed first functioning prototype  Assembled printed circuit board  Constructed testing and presentation fixture  Wrote testing protocols for validation and verification  Investigated alternative valve designs  Won Schoof’s Innovation Design Competition  Attended Posters in the Rotunda

Team AID’s S lution Foley Catheter Three-way Controller Belt-Mounted Battery Rechargeable Pinch Valve Normally Closed Pressure Transducer Inexpensive and Disposable

Device Accessibility  Target audience: individuals with sensory-motor, physical and/or cognitive disabilities  Provides personalized visual, audible, and tactile feedback of bladder status  Safety switch to prevent accidental voiding  Auxiliary port to allow for custom switches  Designed to stabilize hand and requires minimal fine motor movements to operate

New Valve Design  Advantages  Smaller profile  Less obtrusive  Lower power

Testing Objectives  The device is composed of several main parts:  User interface  Urine flow control  Bladder status monitoring  Catheter  Create test protocols for each

User Interface  Must be easily used by a patient with sensory-motor, physical and cognitive disabilities Design AspectPossible User Response  Alert Levels  Bladder status confusion  Alerts too close together  Button placement  Box size  Belt mounting fails  Unable to reach button  Stability issues  Accidental activation

Urine Flow Control  The valve reliably prevents undesired urine flow  The valve allows voiding of the bladder when desired  Foley Catheter is FDA approved EventPossible Outcome  Valve does not open when proper sequence of actions performed  Valve opens when safety switch not engaged  Leakage around catheter to release pressure  Accidental activation and bladder voiding

Bladder Status  Problem: need to filter urine pressure spikes  Possible solution: moving average filter + physiological knowledge  Bladder fills slowly: expect low frequency pressure signal  Implement software low-pass filter

Sources of increased pressure EventsPossible Complication  Coughing  Sneezing  Walking  Breathing  Ascending/descending stairs  Catheter pinched (user obesity, rolling around while sleeping, closing legs)  Sitting vs. standing vs. laying down  Tight clothes  Exercise  Swallowing  Detrusor overactivity  Pressure spikes  Prolonged increase in pressure  Pressure not accurate if catheter is pinched

Future Work  Develop a new device enclosure  Design a smaller PCB with surface mounting  Implement new valve design  Execute verification and validation test plan  System, software and usability  Create website for RERC on AMI National Competition  Win National competition

References john.com/_img/products/pw_a_LiquidPressureSensor.jpg 6.M. Malbrain and D. Deeren, “Effect of bladder volume on measured invtravesical pressure: a prospective cohort study,” Crit. Care, vol. 10, no

Questions? Acknowledgements Wade Bushman, M.D., Ph.D. Naomi Chesler, Ph.D. Michael Malone, M.D. Abby Frese, R.N.