Intervention Device for Handwashing Compliance Claire Flanagan Robyn Hrobsky Adam Rieves Brad Rogers

Outline

COWS in clinics Computers on Wheels –Clinical staff workstation in patient room Mobile between rooms –Used on all medical floors –Streamlined Design –Password Protected –Multiple interventions per patient contact

Handwashing Guidelines Spalding Definition for Decontamination 1 –Intermediate-Level Disinfection Procedure kills vegetative microorganisms, all fungi, and inactivates most viruses APIC Guidelines for Handwashing 2 –Hand not visibly soiled  alcohol-based hand rub –Required after contact with inanimate objects Some Disinfecting methods –Alcohol –Ionic silver –UV-Irradiation

Types of Disinfectants Alcohol Hydrogen Peroxide Iodine Triclosan® Ionic Silver UV-irradiation

Competing Products Microban® Keyboards InduProof® –Antimicrobial surface –Easily cleaned Unotron® –Can be immersed under running water Purell®

Design Constraints Safely dispenses disinfectant Disinfects user’s hands and maintains cleanliness of keyboard Designed for prolonged use Fits seamlessly into clinical environment Retrofitted Cost effective

Problem Statement Hand hygiene –An integral part of a health care professional’s job –The single most important infection control procedure Project Goals –Increase handwashing compliance –Streamline process –Produce an affordable product –Maintain patient/user safety

Design: Phase I Two separate tasks  two separate designs –Disinfect keyboard Ionic silver UV-irradiation Alcohol spray –Disinfect hands Chamber Biometric sensor Alcohol spray

Design: Phase I Keyboard Matrix CriteriaWeightUVSilverAlcohol Spray Compliance Interference with task Long term exposure/safety10 8 Affordability10889 Length of Service10666 Ease of monitoring5534 Installation5435 Testability5424 Ease of manufacture5434 Patient acceptance5445 Incorporation of both tasks1000 TOTAL

Design: Phase I User Matrix CriteriaWeightSensorChamberAlcohol Spray Compliance Interference with task Long term exposure/safety10779 Affordability10 8 Length of Service10858 Installation5433 Ease of monitoring5435 Testability5535 Ease of manufacture5343 Patient acceptance5324 Incorporation of both tasks100 TOTAL

Design: Phase II Atomization –Will quickly evaporate –Purchased spray nozzle (McMaster-Carr, P/N 4759T22) 9-70µm diameter droplets 2.33ml/s flow at 40PSIG –Pressure required Compressed air Peristaltic pump

Design: Phase II Compressed Air Compressed air source –Hospital’s line –Tank on COW Solenoid valve Check valve regulates flow of disinfectant Disinfectant stored in rigid reservoir

Compressed Air Source Computer Controlled Solenoid Valve One-Way Check Valve Reservoir of Disinfectant Design: Phase II Compressed Air Schematic

Design: Phase II Compressed Air Advantages Inexpensive to develop Reliable Low power consumption Easily maintained Disadvantages Reduced mobility Bulky Aesthetics Many wires

Design: Phase II Peristaltic Pump Mechanism: Positive displacement –Low pressure input, high pressure output Commonly used in clinical settings Specialized tubing –Provides constant flow –Chemical/pressure compatibility Rotary or linear mechanism for motor –Three-phase power is favorable Design: –Pumps disinfectant from flexible reservoir through fogging nozzle

Design: Phase II Peristaltic Pump Design

Design: Phase II Peristaltic Pump Advantages Efficient delivery Mobile Flexible reservoir Low-cost product Disadvantages Flow rate of pump must support pressure accumulation Tubing may be expensive to replace Expensive product development phase

Design: Phase II Matrix CriteriaWeight Compressed airPeristaltic Mechanical Complexity Cost Size/mobility 155 Disinfectant Storage 155 Life in Service 105 Installation 105 Power Source TOTAL

Future Work

References 1. Disinfection of Surfaces e23.htm 2. National Guideline Clearinghouse =15&doc_id=3484

Questions???