Gasplasma

GASPLASMAGASPLASMASTERILIZATIONSTERILIZATION

Dr.T.V.Rao MDDr.T.V.Rao MD

Advances in SterilizationAdvances in Sterilization

Sterilization, as a specific discipline, has been Sterilization, as a specific discipline, has been with us for approximately 120 years, since the with us for approximately 120 years, since the invention of the steam autoclave by Charles invention of the steam autoclave by Charles Chamberland in 1879.1 Since that time, we have Chamberland in 1879.1 Since that time, we have seen progressive refinement in steam sterilizers: seen progressive refinement in steam sterilizers: from the early, manually operated equipment to from the early, manually operated equipment to modern microprocessor-controlled, automatic modern microprocessor-controlled, automatic machines. Although the efficiency, reliability, and machines. Although the efficiency, reliability, and performance monitoring of modern equipment is performance monitoring of modern equipment is continually improving, the fundamental process continually improving, the fundamental process remains essentially the same. remains essentially the same.

GAS PLASMAGAS PLASMA

Gas Plasma (vaporized hydrogen Gas Plasma (vaporized hydrogen peroxide)peroxide) is a relatively new option that is a relatively new option that can provide low heat sterility cycles with can provide low heat sterility cycles with none of the off-gassing concerns present none of the off-gassing concerns present with EtO. with EtO. Gas Plasma (VHP)Gas Plasma (VHP) sterilization sterilization has, until now, been exclusively used by has, until now, been exclusively used by large manufacturers as the end line large manufacturers as the end line process for in-house sterilization. process for in-house sterilization.

Beginning of Gas PlasmaBeginning of Gas Plasma

Gas plasma sterilization technology based Gas plasma sterilization technology based of Plasma was patented in 1987, and of Plasma was patented in 1987, and marketed in U S 1993.marketed in U S 1993.

What is Gas PlasmaWhat is Gas Plasma

Plasma is a Plasma is a fourth state of matterfourth state of matter which is which is distinguishable from liquid, solid, or gas. In distinguishable from liquid, solid, or gas. In nature, plasma is widespread in outer nature, plasma is widespread in outer space. space.

Gas plasma generated in an enclosed Gas plasma generated in an enclosed chamber under deep vacuum using Radio chamber under deep vacuum using Radio frequency or Microwave emery to excite frequency or Microwave emery to excite gas molecules are produced charged gas molecules are produced charged particlesparticles

How Gas Plasma works.How Gas Plasma works.

Many particles are in the form of free radicalsMany particles are in the form of free radicals A free radical is an Atom with an unpaired A free radical is an Atom with an unpaired

electron and is a highly reactive specieselectron and is a highly reactive species The mechanism of action of this device is the The mechanism of action of this device is the

production of free radicals within a plasma field production of free radicals within a plasma field that are capable of interacting with essential cell that are capable of interacting with essential cell components, ie is enzymes and nucleic acids. components, ie is enzymes and nucleic acids. And thereby disrupt the metabolism of And thereby disrupt the metabolism of microorganisms.microorganisms.

Identified AdvantagesIdentified Advantages

Materials and device compatibility Materials and device compatibility Rapid turnaround times Rapid turnaround times In-house control of the sterilization In-house control of the sterilization

process process Lower inventory requirements. Lower inventory requirements.

Beneficial for sterilizing temperature-Beneficial for sterilizing temperature-

sensitive polymeric materialssensitive polymeric materials

The advantages of gas plasma sterilization The advantages of gas plasma sterilization include its ability to provide safe, non toxic, include its ability to provide safe, non toxic, dry, low-temperature sterilization in about dry, low-temperature sterilization in about one hour. By-products of plasma one hour. By-products of plasma sterilization are primarily water and sterilization are primarily water and oxygen. Because these by-products are oxygen. Because these by-products are harmless, there is no need for aeration or harmless, there is no need for aeration or environmental hazard concerns. environmental hazard concerns.

Steps in Plasma sterilizationSteps in Plasma sterilization

The Vacuum PhaseThe Vacuum Phase

The chamber is evacuated, reducing internal pressure in The chamber is evacuated, reducing internal pressure in preparation for the subsequent reaction.preparation for the subsequent reaction.

The Injection PhaseThe Injection Phase

A measured amount of liquid peroxide is injected into the A measured amount of liquid peroxide is injected into the chamber, evaporating the aqueous hydrogen peroxide chamber, evaporating the aqueous hydrogen peroxide solution and dispersing it into the chamber, where it kills solution and dispersing it into the chamber, where it kills bacteria on any surface it can reach.bacteria on any surface it can reach.

The Diffusion PhaseThe Diffusion Phase

The hydrogen peroxide vapour permeates The hydrogen peroxide vapour permeates the chamber, exposing all load surfaces to the chamber, exposing all load surfaces to the sterilant and rapidly sterilizes devices the sterilant and rapidly sterilizes devices and materials without leaving any toxic and materials without leaving any toxic residues. At the completion of this phase, residues. At the completion of this phase, the chamber pressure is reduced and the the chamber pressure is reduced and the plasma discharge is initiated.plasma discharge is initiated.

The Plasma PhaseThe Plasma Phase

An electromagnetic field is created in which the An electromagnetic field is created in which the hydrogen peroxide vapour breaks apart, producing a hydrogen peroxide vapour breaks apart, producing a low-temperature plasma cloud that contains low-temperature plasma cloud that contains ultraviolet light and free radicals. Following the ultraviolet light and free radicals. Following the reaction, the activated components lose their high reaction, the activated components lose their high energy and recombine to form oxygen and water.energy and recombine to form oxygen and water.

Phases 1, 2, and 3 are then run a second time for Phases 1, 2, and 3 are then run a second time for added efficacy. This built-in reprocessing assures added efficacy. This built-in reprocessing assures optimal sterilization for even the most difficult-to-optimal sterilization for even the most difficult-to-sterilize devices.sterilize devices.

The Vent PhaseThe Vent Phase

The chamber is vented to equalize the The chamber is vented to equalize the pressure enabling the chamber door to be pressure enabling the chamber door to be opened. There is no need for aeration or opened. There is no need for aeration or cool-down. Devices are ready for cool-down. Devices are ready for immediate use.immediate use.

Graphic representation of Gas Graphic representation of Gas plasma Technologyplasma Technology

Advantages of plasma Advantages of plasma sterilizationsterilization

Low-Temperature Hydrogen Peroxide Low-Temperature Hydrogen Peroxide Gas Plasma (LTHPGP)Gas Plasma (LTHPGP) has a number of has a number of advantages compared to established advantages compared to established sterilization technologies. These include a sterilization technologies. These include a short (one to four hours) sterilization cycle, short (one to four hours) sterilization cycle, low temperature and humidity, no aeration low temperature and humidity, no aeration requirement, no toxic chemical residues or requirement, no toxic chemical residues or environmental impact, and broad environmental impact, and broad compatibility with materials. compatibility with materials.

The Biological Indicator for The Biological Indicator for quality controlquality control

The Biological The Biological indicator used with indicator used with system is Bacillus system is Bacillus atrophaeus spores.atrophaeus spores.

Improvement to New technologyImprovement to New technology

The newer version of unit, which employs The newer version of unit, which employs a new vaporization system that removes a new vaporization system that removes most of the water from hydrogen peroxide, most of the water from hydrogen peroxide, has a cycle time from 28-38 minutes.has a cycle time from 28-38 minutes.

Mode of Action in Gas plasma Mode of Action in Gas plasma usageusage

The process inactivates microorganisms The process inactivates microorganisms primarily by the combined use of hydrogen primarily by the combined use of hydrogen peroxide gas and the generation of free peroxide gas and the generation of free radicals ( hydroxyl and hydroproxyl free radicals ( hydroxyl and hydroproxyl free radicals ) during the plasma phase of the radicals ) during the plasma phase of the cycle.cycle.

Uses of Gas PlasmaUses of Gas Plasma

Materials and devices that cannot tolerate Materials and devices that cannot tolerate high temperatures and humidity such as high temperatures and humidity such as some plastics, electrical devices, and some plastics, electrical devices, and corrosion- susceptible metal alloys, can be corrosion- susceptible metal alloys, can be sterilized by hydrogen peroxidesterilized by hydrogen peroxide

This method proved compatible with most This method proved compatible with most (>95%) medical devices and materials (>95%) medical devices and materials tested.tested.

Gas Plasma ApparatusGas Plasma Apparatus

Gas Plasma Work StationGas Plasma Work Station

Medical Medical instrumentation can instrumentation can be sterilized through a be sterilized through a hydrogen peroxide hydrogen peroxide gas plasma process gas plasma process with the with the Sterrad Sterrad 100100 system (Advanced system (Advanced Sterilization Sterilization Products). Photo: Products). Photo: Advanced Advanced Sterilization ProductsSterilization Products

DisadvantagesDisadvantages

The disadvantages of gas plasma The disadvantages of gas plasma sterilization are that it may not penetrate sterilization are that it may not penetrate well, especially in channels or devices well, especially in channels or devices designed with long lumens. In addition, the designed with long lumens. In addition, the gas plasma sterilization method may gas plasma sterilization method may corrode some materials and cannot be corrode some materials and cannot be used on paper, cellulose or linen. An used on paper, cellulose or linen. An additional drawback to plasma sterilizers is additional drawback to plasma sterilizers is their small chamber. their small chamber.

Acceptable TechnologyAcceptable Technology

According to experts, only a few disadvantages According to experts, only a few disadvantages associated with gas plasma sterilization exist. associated with gas plasma sterilization exist. These include the inability to process liquids, These include the inability to process liquids, powders, or strong absorbers (cellulosics), and powders, or strong absorbers (cellulosics), and some lumen restrictions. Also, gas plasma some lumen restrictions. Also, gas plasma sterilization is not recommended for liquids and sterilization is not recommended for liquids and other devices that can be damaged physically or other devices that can be damaged physically or changed by exposure to low pressure. changed by exposure to low pressure.

STERRAD TECHNOLOGYSTERRAD TECHNOLOGY

In 1993, the STERRAD Technology In 1993, the STERRAD Technology received clearance and was introduced received clearance and was introduced into the United States. It is now available into the United States. It is now available in more than 60 countries throughout the in more than 60 countries throughout the world with over 6,000 units sold, making it world with over 6,000 units sold, making it the world's fastest growing sterilization the world's fastest growing sterilization technology. technology.

STERRAD 100STERRAD 100

The STERRAD 100 sterilization system The STERRAD 100 sterilization system (Johnson & Johnson Medical Ltd) uses (Johnson & Johnson Medical Ltd) uses low temperature hydrogen peroxide gas low temperature hydrogen peroxide gas plasma for sterilization of heat labile plasma for sterilization of heat labile equipment. equipment.

The topic created as per The topic created as per guidelines for Disinfection guidelines for Disinfection

and sterilization in Healthcare and sterilization in Healthcare Facilities,2008Facilities,2008

CDCCDC

Dr.T.V.Rao MDDr.T.V.Rao MD

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