Distributed surgical instrument sterilization using …

1 THE NEED FOR surgical CARED istributed surgical instrument sterilization usingSOLAR powered AUTOCLAVESin low resource APPROPRIATE AND AFFORDABLE SOLUTIONSOLARCLAVE SYSTEM DESIGNCOLLABORATIONADVANTAGES OF SOLAR STERILIZATIONE ffectivenessCostBoiling waterChemical SterilantsCentralized HospitalTabletop AutoclaveDEVELOPMENTSOLAR OVEN ISOLAR OVEN IISOLARCLAVESUBASSEMBLIES8 PARTS5 PARTS8 PARTSSUPPLY CHAIN COMPLEXITY100% LOCAL MATERIALS90% LOCAL MATERIALS90% LOCAL MATERIALS; 100% LOCAL REPLACEABLEPARTSASSEMBLY TIME1 DAY1 DAY3 DAYSMANUFACTURETRAINING 7 DAYS 8 DAYS10 DAYSUSER TRAINING3 HOURS3 HOURS1 DAYVOLUMELOWLOWHIGHCOST~$300~$300~ $400 The surgical care gap between developing and developed countriescould be substantially reduced through integrated strategiesincluding appropriate medical equipment design for surgicalprocedures in low-infrastructure WHO states that most of the surgical care required to reducethe global disease burden can be given at the primary level ofhealth care, which for most of the world, is provided by clinics in developing countries provide primary carefor 3 billion people worldwide.

2 But more than half of them do nothave access to electricity. Additionally, although they lack theproper equipment, nurses at these clinics are faced with thedecision to compromise patient safety by attempting to providecare. When minor wound injuries are left untreated or areinappropriately treated by the primary care clinics, infections canrapidly spread. Every year there are 50-60 million people inthedeveloping world suffering from wound injuries. Even in areaswhere surgeries are already performed, one fifth of the patientssuffer from post-operation infection, due to, among other causes,the use of improperly sterilized equipment used in the procedure(Gomez-Marquez, 2010).

3 Figure 4 compares current options for sterilization against thecost and effectiveness of those efforts. Moving from the left sideof the compass,boiling waterto clean instruments is notendorsed by the WHO as a reliable method of sterilization . Itdoes not kill 100% of the microbes present on surgical sterilantsare another option for instrumentsterilization. However, this process is complex and which create ahigh probability for user error to result in improperly sterilizedequipment. Rural health clinics without access to electricitytypically use sterilization equipment at central hospitals,often aday-long bus ride away. Atcentral hospitals, high- powered ,electric autoclaves are one of themain pieces of equipmentwhich regularly fails and cannot run on a back-up generator in apower outage.

4 Thus, when nurses bring their equipment fromthe rural clinics to be sterilized, there is a high probability thatthe autoclave at the hospital will not be another option, but are prohibitively expensiveand most require a source of electricity for power. Thealternative source of power is a propane stove, however,according to the logistics supervisor of Doctors Without Borders,the supply chain for these items is limited. Our solution:a solarpowered sterilization cycle for the solar autoclaveis the same as a tabletop autoclave, but is powered usingrenewable energy, a free and abundant the world s burden of surgical diseases increases, sodoes the gap between access to life saving and disabilitypreventing surgical care, both between and withincountries.

5 As seen in Figure 1, less than 5% of the world ssurgical procedures are performed in countries ranked inthe lowest third of per capita health expenditure. Barriersto the delivery of safe and timely surgery includedeficiencies in capacity and is often theonly solution to prevent disabilities and death fromconditions resulting from road traffic accidents, falls,burns, disasters, domestic violence, pregnancy relatedcomplications, infections and congenital defects. The WHOestimates that 500,000 women die annually fromcomplications in pregnancy that can be easily solved withsimple surgical intervention at the primary health clinicpoint of complications and other surgicaldiseases seen in Figure 2 account for11% of the GlobalDisease 11 in 5 wound sufferers in developing countries suffers from in 5 wound sufferers in developing countries suffers from 2We describe a new method for medicalinstrument sterilization using solar energyinstead of conventional fuels, the technology allows for the safe andreliable steam sterilization of surgicalinstruments in clinics without electricity.

6 Such as those often found in the autoclave is defined as a vesselcapable of holding high pressure steam at15psi and insulation to maintain theinternal temperature at 121 solarautoclave uses a parabolic solarconcentrator and a small boiler to collectsolar energy to generate steam that istransferred to an insulated pressure1 Speigel, David A. MD. Health Volunteers Overseas. WHO and Essential surgical Care. July Weiser, Thomas G., et al. An estimation of the global volume of surgery: a modeling strategy based on available data. The Lancet. Vol 372 July 12, 2008, Centers for Disease Control, Guidelines for Disinfection and sterilization in Healthcare Facilities WHO, Emergency and Essential Surgery: the backbone of primary health care, (accessed on 26 Aug 2010)5 Komp, R.

7 , et al. Solar autoclaves for sterilizing medical instruments in remote settings. GLOBAL SURGERIESF igure 3 GLOBAL DISEASE BURDENF igure 4 The SolarclaveTMresearch team has partnerships with Universities, NGOs, medical professionals and engineers for the devicedesign, testing and implementation. We welcome the opportunity to collaborate with other medical care providers deliveringsurgical care in resource poor settings and practioners developing solutions to surgical needs in developing and an electronic sterilization indicator (Figure 3). Proof of concept experimentation was done to ensure that the250ML boiler and parabolic concentrator generated the appropriate amount of steam for a 5L insulated pressure testing showed the system will need two concentratorsfor this amount of steam.

8 A sterilization indicator is measurestemperature and activate s an LED when the appropriate measures for sterilization are reached. Advantages of this solarautoclave design include: (1) decoupled solar concentrator and pressure vessel to reduce volatility in solar collection (2)ability to scale the system size with additional solar concentrators (3) modular electronics to measure temperature,pressure, sunlight and external energy (4) design for manufacturing and flat pack SolarclaveTMSolar Concentrator and BoilerNicaragua 2010 Solar Autoclav