Pressure Sore Alleviation Device

1. Pressure Sore Alleviation Device Senior Design Team P6203 Adam Hagerty Elizabeth Hampton Scott Keppel Brian Phillips Coordinator: Dr. Elizabeth DeBartolo Sponsor: Kristen Quinlan, ARC of Monroe

2. Outline • ARC of Monroe Overview • What is a Pressure Sore? • Project Needs • Concepts Developed • Design, Analysis, and Build • Budget • Final Product • ARC of Monroe Feedback (1 week of use)

3. ARC of Monroe Overview • Organization that has provided care to mentally/physically disabled patients for many years • They are looking for a way to relieve pressure sores on a single patient • Want device to function to eliminate need for the nursing staff to constantly be disrupting patient’s sleep for adjustment

4. Project Team Goals • Create device to alleviate pressure spots on clients body • Make it affordable to stay within budget • Make it safe and reliable for all users (i.e. – Nursing staff and client)

5. Problems Discovered • Client has pressure sores • Client has difficulty sleeping at night • Client is disabled and deaf • ARC doesn’t have effective device to alleviate pressure sores without constant supervision

6. What is a Pressure Sore?? • Develop due to constant pressure on an area of skin • This reduces blood supply to the area • Causing • Cell death • Breakdown of the skin • Development of an open sore Picture Courtesy of www.WebMD.com

7. 4 Stages of a Pressure Sore • Stage 1 Pressure Sore • Skin is red or discolored • Redness does not go away 30 minutes after pressure is removed • Stage 2 Pressure Sore • Upper layer of the skin is broken • Creates a shallow, open sore • Drainage may or may not be present Pictures Courtesy of www.WebMD.com

8. 4 Stages of a Pressure Sore • Stage 3 Pressure Sore • Break in the skin extends through the second skin layer into fat tissue • Wound is deeper than in Stage 2 • Stage 4 Pressure Sore • Breakdown extends into the muscle and possibly down to the bone • Usually lots of dead tissue and drainage are present. Pictures Courtesy of www.WebMD.com

9. 1 Part of the Cure • This device is only one part of the pressure sore problem • Although this device will alleviate pressure it will not cure a pressure sore, it is for prevention only • Healing of a pressure sore is done by two methods: Proper medical treatment and proper nutrition

10. Needs of Project • Safe for user • Alleviate long-term pressure areas • Stay in budget (<$1500) • Be waterproof • Rotate through position settings • Rotate at intervals • Comfortable to user • Simple user interface • Low/Easy Maintenance (repair) • Power source location • Operate quietly • Control interface location

11. Specifications • Sales Price: $1500 • Supportable Weight (max): 300 lbs • Number of times patient needs assistance during sleep period due to an issue with the device: <1 • # of Cycle Patterns: 3-5 • Duration of Each Cycle Pattern: 30-60 min • # Of Buttons on User Interface: 5 max • Life of Product: 7 yrs • Selectable Duration for Each Cycle Pattern: 1-3 • Size of Mattress (in2): 54”x75” • # of Main Components: 10 max • Distance to User Interface: 25 ft • Distance to Outlet: 10 ft

12. Concepts • Concept # 1 – Air bladder system • Concept # 2 – Cylinder mechanism • Concept # 3 – Alternating track system • Concept # 4 – Hinged mattress • Concept # 5 – Water bladder system

13. CONCEPT # 1: AIR BLADDER

14. CONCEPT # 2: CYLINDER SYSTEM

15. CONCEPT # 3: ALTERNATING TRACK SYSTEM

16. CONCEPT # 4: HINGED MATTRESS

17. CONCEPT # 5: WATER BLADDER

18. CONCEPT SELECTION • CONCEPT # 1: AIR BLADDER • Based on Pugh analyses • Determined to be best suited for needs

19. Design Guidelines • MATTRESS • 3 cycles for alleviation • 2 moving cycles • 1 stationary cycle • Twin size section • Foam border to fill full size bed of client • Water proof mattress cover

20. Cycles of Alleviation CYCLE 1 CYCLE 2 CYCLE 3

21. Patient Statistics W=115lbs. H=56in. Assuming 18in. wide patient Worst Case: (300lbs on 5 Tubes) Client Case: Air Cell Analysis

22. Pump Analysis • Pump usage • Inflate and deflate 10 air cells • The air pump must produce .23cfm to properly inflate the mattress in 20 minutes. • Will use pump from Sentech (110V) Data Courtesy of www.sentechmedical.com

23. User Box • Contains 4 lighted switches for cycle control • Holds microcontroller, solid state relays, and other electrical components • Enclosure is safe for electrical devices • Mounts to wall with ease

24. Pump Box • Contains switch and power connection for pump • Holds pump, 2 valves, 2 pressure sensors, and other electrical components • Again, safe for electrical devices and easy mounting capability

25. Foam Containment • Foam used to surround and contain air cells • Foam purchased from www.efoamstore.com • Can be made in any shape for any specific application (aka bedding) • Yellow foam is medium grade bedding foam • Medium foam will compress approximately .75” • Blue foam is firm grade bedding foam • Firm foam will compress approximately .25”

26. FINAL ASSEMBLY-MATTRESS • Consists of 4 foam sides, 4 foam inserts, 1 foam base, and 10 air cells

27. Electrical Analysis • The controls are outside of the bedroom due to customer requirement • 4 lighted switches used to control the cycles • Sense pressure in air tubes • Open valves when the pressure is above the set level (discussed later)

28. Sensing Pressure • Need to sense pressure around 20mmHg (up to 50 mmHg) • This pressure sensor ranges from 0 to 51 mmHg which is perfect for this application • Controller input needs to switch to high when at proper pressure • VO-1.5=.09*R (Used this to determine resistor necessary for proper pressure switching point) www.honeywell.com

29. Comfort Analysis • Used 20 mmHg as base point for analysis • Adjusted Resistor from 6 ohms to 18 ohms where maximum comfort was experienced • An 18 ohm resistor gave a voltage of 3.12 volts and an approximate pressure of 33 mmHg Start • Used this calculation to determine • resistor needed to meet comfort • level • 1.5 V is the high/low trip point for • the controller and .09A is the • current of the controller End

30. Opening Valves • A solid state relay was used to open the valves with the 5VDC, 30mA signal the controller outputs • Relay, when signaled would allow a 12VDC signal to travel to the valve • Two relays were used to control each valve separately • When 12 VDC is passed across valve, exhaust port is opened • Valve closes when 12 VDC is removed • Mattress pressure is regulated through these valves Figure Courtesy of www.norgren.com

31. Electrical Schematic

32. BASIC stamp microcontroller Excellent for small control applications Simple programming language 16 I/O ports for connections This project used 8 ports System Control

33. System Control • Pin Assignments • Pins 0 and 1 were used for pressure sensors • Pins 3 and 4 were used for valve control • Pins 10-13 were used for lighted switch control

34. System Control • Depending on switch selected program will select proper cycle time (30, 45, 60 minute cycles, or Full Inflate) • If no switch is selected mattress will automatically full inflate • If multiple switches are selected mattress will choose first switch • These times are based on count commands within the program • To determine the proper count testing was performed on the system for each required time.

35. System Control • Air pump is always on • System pressure is controlled by valves and pressure sensors as seen earlier • When pressure in either cell cycle exceeds 33 mmHg, stamp input 0 or 1 is signaled to switch to high • This switch signals input 3 or 4 to switch high, opening the valve associated with it • This valve remains open for 5 seconds and then closes • If cycle calls for valve to be open, input 3 or 4 is left high to release pressure from the required set of air cells • Cycles rotate between the 3 patterns until new switch is selected and old switch is shut off

36. Budget Overview • Budget Available = $1500 • Total Cost of Project = $920 • This project was under budget by $580

37. Final Product

38. Arc of Monroe Feedback • Patient is sleeping uninterrupted throughout the night (4 Nights since installation) • Nursing staff says patient looks comfortable in mattress system • No problems with mattress system recorded, all positive feedback!

39. Recommendations for Future Work • This device is made specifically for a 115 lb client leaving available the variable user side of this project • This device is only a prototype, making it for mass production would be another area to investigate

40. Special Thanks • This material is based upon work supported by the National Science Foundation under Award No. BES-0527358. • The electrical enclosure for our pump, valves, and pressure sensors was provided courtesy of Fibox.

41. Disclaimer • Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation.

42. References • [1] www.sentechmedical.com • [2] www.parallax.com • [3] www.efoamstore.com • [4] www.neurocare.com • [5] www.caregiverproducts.com • [6] www.medicalharmony.com • [7] www.medicalproductsdirect.com • [8] www.therohogroup.com • [9] www.sunrisemedical.com • [10] www.invacare-ccg.com • [11] www.medicalsupplis4all.com • [12] www.webMD.com • [13] www.foamorder.com • [14] www.airdimensions.com • [15] www.norgren.com • [16] www.fibox.com

43. Questions ? ? ?