Flash sterilization is a last resort sterilization method used when there is insufficient time to sterilize an item through standard methods. It is not recommended for implantable devices due to risk of infection, but may be unavoidable in some cases. Proper recordkeeping is essential when flash sterilizing implantable devices.
Various low-temperature sterilization technologies have been explored as alternatives to ethylene oxide (EO) due to environmental regulations and health concerns. Acceptable alternative technologies include 100% EO, EO with different stabilizing gases, hydrogen peroxide gas plasma, and peracetic acid. No technology is ideal for all devices and understanding limitations is important for proper application.
EO
Disinfectants and sterilization methods. rev.09302013Eka Selvina
This document provides guidance on disinfectants and sterilization methods. It defines key terms and discusses various classes of chemical disinfectants like aldehydes, halogen compounds, quaternary ammonium compounds, phenolics, acids/alkalis, heavy metals and alcohols. It also covers sterilization methods such as steam autoclaving, dry heat, radiation and vapors/gases. Tables provide summaries of practical disinfectants and their characteristics, potential applications and examples of proprietary disinfectants. The document aims to assist in selecting appropriate disinfectants and sterilization methods.
This document discusses sterilization methods for infection control in medical offices. It states that instrument sterilization is an important part of infection control. The main sterilization methods discussed are steam under pressure, dry heat, chemical vapor, and ethylene oxide gas. It provides details on cleaning, packaging, and monitoring instruments to ensure effective sterilization. Biological indicators that test for microbial kill are emphasized as the ultimate criteria for verifying sterilization.
This document discusses sterilization and disinfection in dentistry. It defines sterilization as killing all microorganisms, including bacterial spores, while disinfection only eliminates most pathogens. It describes various sterilization methods like steam, dry heat, radiation, filtration and chemicals. Moist heat sterilization using an autoclave at 121.5°C for 15-30 minutes is the most reliable method. Proper cleaning and packaging of instruments before sterilization is also covered. The document emphasizes the importance of sterility assurance through various indicators to ensure the sterilization process was successful.
This document provides information on sterilization and infection control in dentistry. It defines key terms like sterilization, disinfection, antisepsis and asepsis. It describes the chain of infection and common routes of disease transmission in a dental office. It discusses various methods of disinfection and sterilization used in dentistry, including heat, chemicals, filtration and radiation. The most common sterilization methods used in dental offices are described as steam autoclaving, chemiclaving and dry heat ovens. The document emphasizes the importance of sterilizing dental instruments according to their risk classification as critical, semi-critical or non-critical to prevent disease transmission.
The document discusses sterilization processes. It describes sterilization as the process of destroying all life forms from an object or medium. There are several sterilization methods including heat, radiation, gases, and liquids. Effective sterilization requires proper pre-sterilization preparation, use of the correct sterilization method for the materials, validation of the sterilization process, and maintenance of sterile conditions during storage, packaging, and use.
Decontamination of anaesthesia equipmentsshahchetank1
The document discusses decontamination of anesthesia equipment. It provides evidence that anesthesia equipment can transmit infections based on multiple studies over decades. Equipment like breathing bags, humidifiers, ventilators, and laryngoscopes have been implicated in spreading pathogens. The document concludes that a 8% contamination rate of equipment is too high a risk. It then describes the processes of cleaning, disinfection and sterilization needed for anesthesia equipment depending on the item's classification as critical, semi-critical, or non-critical. Chemicals and methods used for effective decontamination are also outlined.
Sterilization completely kills all living organisms, while disinfection reduces microbial growth but may not kill all organisms. The document discusses various sterilization and disinfection methods used in dentistry, including physical methods like boiling, dry heat, steam autoclaving, and radiation. It also covers chemical methods using substances like eugenol, alcohol, chlorhexidine, and sodium hypochlorite. Combination methods like chemical vapor pressure sterilization are also presented. Maintaining proper concentration, temperature, and pH is important for effective sterilization and disinfection.
sterization and asepsis in maxillofacial surgeryJoel D'silva
The document discusses sterilization, disinfection and asepsis. It provides historical context on the development of practices like hand washing and use of antiseptics from figures like Holmes, Sommelweis and Lister. It defines key terms and describes various physical and chemical methods of sterilization and disinfection like heat, radiation, filtration and chemicals. These methods are used to sterilize different medical equipment and maintain aseptic techniques important for preventing surgical infections.
Disinfectants and sterilization methods. rev.09302013Eka Selvina
This document provides guidance on disinfectants and sterilization methods. It defines key terms and discusses various classes of chemical disinfectants like aldehydes, halogen compounds, quaternary ammonium compounds, phenolics, acids/alkalis, heavy metals and alcohols. It also covers sterilization methods such as steam autoclaving, dry heat, radiation and vapors/gases. Tables provide summaries of practical disinfectants and their characteristics, potential applications and examples of proprietary disinfectants. The document aims to assist in selecting appropriate disinfectants and sterilization methods.
This document discusses sterilization methods for infection control in medical offices. It states that instrument sterilization is an important part of infection control. The main sterilization methods discussed are steam under pressure, dry heat, chemical vapor, and ethylene oxide gas. It provides details on cleaning, packaging, and monitoring instruments to ensure effective sterilization. Biological indicators that test for microbial kill are emphasized as the ultimate criteria for verifying sterilization.
This document discusses sterilization and disinfection in dentistry. It defines sterilization as killing all microorganisms, including bacterial spores, while disinfection only eliminates most pathogens. It describes various sterilization methods like steam, dry heat, radiation, filtration and chemicals. Moist heat sterilization using an autoclave at 121.5°C for 15-30 minutes is the most reliable method. Proper cleaning and packaging of instruments before sterilization is also covered. The document emphasizes the importance of sterility assurance through various indicators to ensure the sterilization process was successful.
This document provides information on sterilization and infection control in dentistry. It defines key terms like sterilization, disinfection, antisepsis and asepsis. It describes the chain of infection and common routes of disease transmission in a dental office. It discusses various methods of disinfection and sterilization used in dentistry, including heat, chemicals, filtration and radiation. The most common sterilization methods used in dental offices are described as steam autoclaving, chemiclaving and dry heat ovens. The document emphasizes the importance of sterilizing dental instruments according to their risk classification as critical, semi-critical or non-critical to prevent disease transmission.
The document discusses sterilization processes. It describes sterilization as the process of destroying all life forms from an object or medium. There are several sterilization methods including heat, radiation, gases, and liquids. Effective sterilization requires proper pre-sterilization preparation, use of the correct sterilization method for the materials, validation of the sterilization process, and maintenance of sterile conditions during storage, packaging, and use.
Decontamination of anaesthesia equipmentsshahchetank1
The document discusses decontamination of anesthesia equipment. It provides evidence that anesthesia equipment can transmit infections based on multiple studies over decades. Equipment like breathing bags, humidifiers, ventilators, and laryngoscopes have been implicated in spreading pathogens. The document concludes that a 8% contamination rate of equipment is too high a risk. It then describes the processes of cleaning, disinfection and sterilization needed for anesthesia equipment depending on the item's classification as critical, semi-critical, or non-critical. Chemicals and methods used for effective decontamination are also outlined.
Sterilization completely kills all living organisms, while disinfection reduces microbial growth but may not kill all organisms. The document discusses various sterilization and disinfection methods used in dentistry, including physical methods like boiling, dry heat, steam autoclaving, and radiation. It also covers chemical methods using substances like eugenol, alcohol, chlorhexidine, and sodium hypochlorite. Combination methods like chemical vapor pressure sterilization are also presented. Maintaining proper concentration, temperature, and pH is important for effective sterilization and disinfection.
sterization and asepsis in maxillofacial surgeryJoel D'silva
The document discusses sterilization, disinfection and asepsis. It provides historical context on the development of practices like hand washing and use of antiseptics from figures like Holmes, Sommelweis and Lister. It defines key terms and describes various physical and chemical methods of sterilization and disinfection like heat, radiation, filtration and chemicals. These methods are used to sterilize different medical equipment and maintain aseptic techniques important for preventing surgical infections.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
This document discusses various sterilization techniques used to destroy microorganisms. It defines sterilization as the killing or removal of all microorganisms, including bacterial spores. The goals of sterilization are to ensure preparations are free from microbes and safe for use. Effectiveness depends on the sterilizing material, agent, and time. Physical methods include dry heat, moist heat, and radiation sterilization techniques. Chemical methods involve the use of gaseous agents and disinfectants like ethylene oxide and formaldehyde.
Disinfection and sterilization guidelines what you need to know 2007Manel Ferreira
This document provides an overview and recommendations for disinfection and sterilization in healthcare facilities. It discusses the classification of medical equipment based on intended use as critical, semicritical, or noncritical. Critical items require sterilization to eliminate all microbes. Semicritical items require high-level disinfection to kill all microbes except for some bacterial spores. Noncritical items require low-level disinfection to kill vegetative bacteria and viruses. Common sterilization and disinfection methods are outlined for each classification. The document also reviews factors influencing efficacy and provides recommendations for monitoring sterilizers and proper storage of sterile items.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
This document discusses asepsis and sterile technique in healthcare. It defines key terms like pathogens, indigenous microflora, and types of human-microbe relationships. Factors that increase the risk of surgical site infections are described. The document outlines the characteristics, growth requirements, and transmission of different microbes. It also explains the principles of asepsis, sterilization, disinfection, and the processes for cleaning and sterilizing surgical instruments.
Sterilization is used to destroy all microbial life through physical or chemical processes. It is important for reducing deaths from infection, improving surgical techniques and health conditions. Sterility assurance levels define the probability of an item remaining non-sterile after sterilization. Common sterilization methods include heat, steam, radiation, filtration, ethylene oxide, and hydrogen peroxide. Regulations and standards from organizations like the ISO aim to harmonize sterilization practices globally.
Sterilization of operative & endodontic instrumentsSk Aziz Ikbal
This document provides guidelines for sterilizing dental instruments to prevent the transmission of infectious diseases between patients. It discusses various sterilization methods like steam sterilization, dry heat sterilization, chemical vapor sterilization, and ethylene oxide sterilization. For endodontic instruments, steam sterilization is recommended as the most effective method. Individual instruments can also be sterilized using methods like immersion in disinfectant solutions or passing through a flame. Proper cleaning of instruments before sterilization is emphasized to reduce microbial load. The objectives are to control disease transmission during dental procedures and protect staff through implementing sterilization protocols.
The document discusses sterilization and disinfection methods and commonly used disinfectants. It defines sterilization as destroying all microorganisms including spores and viruses, while disinfection reduces microorganisms but may not eliminate spores or viruses. Common sterilization methods include heat sterilization using dry heat, moist heat and autoclaving, as well as chemical methods using alcohols, aldehydes, halogens, and heavy metals. Commonly used disinfectants mentioned include ethanol, povidone iodine, glutaraldehyde, formalin, hydrogen peroxide, chlorhexidine, and chloroxylenol. The document also outlines different levels of disinfection.
This document discusses various methods of sterilization and disinfection. Sterilization aims to remove all microorganisms, while disinfection targets pathogenic organisms. Physical methods include heat, filtration, and radiation. Chemical agents like alcohols, aldehydes, halogens, and phenols can also be used. Moist heat via autoclaving under pressure is effective at sterilizing materials like instruments. Chemical disinfectants are commonly used to prevent infections on skin and wounds. Proper sterilization and disinfection are important for removing microbes from medical supplies and clinical environments.
Sterilization kills all microbes including spores, while disinfection kills most pathogens but not necessarily all spores. Sterilization methods include heat (dry heat, moist heat like autoclaving), radiation, filtration, gases (ethylene oxide), and plasma. Autoclaving at 121°C for 20 minutes is the most effective sterilization method. Other methods like dry heat, boiling, filtration and chemicals are used for heat-sensitive items or liquids. Proper monitoring of the sterilization process is important to ensure complete sterilization.
This document provides an overview of cleaning, disinfection and sterilization processes used in healthcare settings. It describes the basic principles and key differences between cleaning, disinfection and sterilization. It outlines the Spaulding classification system for categorizing medical equipment as critical, semi-critical or non-critical to determine the appropriate level of processing required. Examples are provided for each category. Monitoring and documentation of cleaning and sterilization processes are also discussed.
This document discusses sterilization in dentistry. It defines sterilization as the process of destroying all microbial life from surfaces and instruments using physical and chemical methods. Sterilization is important in dentistry to prevent the spread of infections between patients and dental staff through contaminated instruments. Instruments are classified as critical, semi-critical, or non-critical depending on infection risk. Common sterilization methods discussed are heat (dry and moist), radiation, and chemicals. Monitoring of sterilization includes mechanical, chemical, and biological indicators to ensure the process was effective.
The document discusses proper procedures for cleaning and sterilizing dental instruments. It outlines the following key steps: 1) Clean instruments manually or using an ultrasonic cleaner or washer; 2) Dry cleaned instruments with disposable cloth; 3) Package instruments in sterilization wraps; 4) Sterilize using steam, chemical vapor, or dry heat sterilization methods approved for dental use; 5) Store sterilized packaged instruments to maintain sterility. Proper cleaning is essential for effective sterilization.
Sterilization and disinfection are important for preventing transmission of diseases between patients and healthcare professionals. Proper cleaning and use of barriers like gloves and masks are required. Instruments must be properly sterilized depending on their risk category using methods like steam, dry heat, or chemicals. Effectiveness is ensured through biological monitoring. Disinfectants and antiseptics are used to clean surfaces and skin but do not guarantee sterilization. Clinical waste requires appropriate disposal to prevent further contamination.
This document discusses sterilization, disinfection, and infection control procedures for surgical instruments and implants. It covers key topics such as:
- The importance of cleaning instruments before disinfection or sterilization to remove organic materials.
- Categorizing instruments as critical, semi-critical, or non-critical based on infection risk to determine the appropriate level of processing needed.
- Common sterilization methods like steam sterilization, dry heat, and chemical vapor that are used depending on the material.
- Guidelines for disinfecting environmental surfaces and categorizing them based on risk of contamination.
- Recommendations for proper hand hygiene and the use of personal protective equipment to
5.anaesthetic airway equipment and infectionHenok Eshetie
This document provides guidelines on infection control and cleaning of anaesthetic airway equipment. It defines key terms like asepsis, antisepsis, decontamination, disinfection, and sterilization. Cleaning airway equipment involves decontamination, cleaning, and either disinfection or sterilization. Equipment is classified as critical, semi-critical, or non-critical depending on its contact with patients. Proper hand hygiene and cleaning, disinfection or sterilization of equipment after each use is essential to prevent spread of infection. Chlorine solution is commonly used for decontamination, and high-level disinfection or sterilization is recommended for critical equipment.
The document discusses various methods of sterilization used in dentistry. It defines key terms like sterilization, disinfection, asepsis, and provides a brief history of the development of sterilization concepts. It then describes various physical methods of sterilization like heat, filtration, radiation and chemical methods. The major physical methods discussed are dry heat using hot air oven or flaming, moist heat using steam under pressure in an autoclave, and filtration. It provides details on the mechanisms and procedures for each method.
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
Sterilisation and disinfection questionsandrewmidd
The document discusses methods for preventing cross-infection including the use of disposable items, disinfection, and sterilization. It defines these prevention methods and provides examples of vaccines and items that would be considered non-hazardous, hazardous, or special clinical waste. It also addresses procedures for dealing with sharps injuries and identifies items that would be pre-sterilized for use.
This document discusses three common methods of low-temperature sterilization - ethylene oxide, hydrogen peroxide, and ozone. It outlines the basic requirements for any sterilization system including effectiveness, safety, monitoring, and material compatibility. For each method, it describes the sterilization process, key parameters, safety considerations, and methods for monitoring sterilization completion. The document concludes with an overview comparing the main features of the three low-temperature sterilization processes.
Assembly Magazine Sterilizing Medical Devices Requires Friendly AgentsClark W. Houghtling
The best sterilization process for medical devices depends on the materials used. Steam is effective but limits materials that can withstand heat. Ethylene oxide (EO) is friendly to most materials but cannot sterilize liquids or gas-impermeable packages. Nitrogen dioxide damages cellulose, polyurethane, and nylon. Radiation breaks polymer bonds and discolors glass. Material compatibility determines the sterilization method, though switching materials increases costs. Different methods are complementary, with EO accounting for over 50% of sterilization and reducing processing time through new techniques.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
This document discusses various sterilization techniques used to destroy microorganisms. It defines sterilization as the killing or removal of all microorganisms, including bacterial spores. The goals of sterilization are to ensure preparations are free from microbes and safe for use. Effectiveness depends on the sterilizing material, agent, and time. Physical methods include dry heat, moist heat, and radiation sterilization techniques. Chemical methods involve the use of gaseous agents and disinfectants like ethylene oxide and formaldehyde.
Disinfection and sterilization guidelines what you need to know 2007Manel Ferreira
This document provides an overview and recommendations for disinfection and sterilization in healthcare facilities. It discusses the classification of medical equipment based on intended use as critical, semicritical, or noncritical. Critical items require sterilization to eliminate all microbes. Semicritical items require high-level disinfection to kill all microbes except for some bacterial spores. Noncritical items require low-level disinfection to kill vegetative bacteria and viruses. Common sterilization and disinfection methods are outlined for each classification. The document also reviews factors influencing efficacy and provides recommendations for monitoring sterilizers and proper storage of sterile items.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
This document discusses asepsis and sterile technique in healthcare. It defines key terms like pathogens, indigenous microflora, and types of human-microbe relationships. Factors that increase the risk of surgical site infections are described. The document outlines the characteristics, growth requirements, and transmission of different microbes. It also explains the principles of asepsis, sterilization, disinfection, and the processes for cleaning and sterilizing surgical instruments.
Sterilization is used to destroy all microbial life through physical or chemical processes. It is important for reducing deaths from infection, improving surgical techniques and health conditions. Sterility assurance levels define the probability of an item remaining non-sterile after sterilization. Common sterilization methods include heat, steam, radiation, filtration, ethylene oxide, and hydrogen peroxide. Regulations and standards from organizations like the ISO aim to harmonize sterilization practices globally.
Sterilization of operative & endodontic instrumentsSk Aziz Ikbal
This document provides guidelines for sterilizing dental instruments to prevent the transmission of infectious diseases between patients. It discusses various sterilization methods like steam sterilization, dry heat sterilization, chemical vapor sterilization, and ethylene oxide sterilization. For endodontic instruments, steam sterilization is recommended as the most effective method. Individual instruments can also be sterilized using methods like immersion in disinfectant solutions or passing through a flame. Proper cleaning of instruments before sterilization is emphasized to reduce microbial load. The objectives are to control disease transmission during dental procedures and protect staff through implementing sterilization protocols.
The document discusses sterilization and disinfection methods and commonly used disinfectants. It defines sterilization as destroying all microorganisms including spores and viruses, while disinfection reduces microorganisms but may not eliminate spores or viruses. Common sterilization methods include heat sterilization using dry heat, moist heat and autoclaving, as well as chemical methods using alcohols, aldehydes, halogens, and heavy metals. Commonly used disinfectants mentioned include ethanol, povidone iodine, glutaraldehyde, formalin, hydrogen peroxide, chlorhexidine, and chloroxylenol. The document also outlines different levels of disinfection.
This document discusses various methods of sterilization and disinfection. Sterilization aims to remove all microorganisms, while disinfection targets pathogenic organisms. Physical methods include heat, filtration, and radiation. Chemical agents like alcohols, aldehydes, halogens, and phenols can also be used. Moist heat via autoclaving under pressure is effective at sterilizing materials like instruments. Chemical disinfectants are commonly used to prevent infections on skin and wounds. Proper sterilization and disinfection are important for removing microbes from medical supplies and clinical environments.
Sterilization kills all microbes including spores, while disinfection kills most pathogens but not necessarily all spores. Sterilization methods include heat (dry heat, moist heat like autoclaving), radiation, filtration, gases (ethylene oxide), and plasma. Autoclaving at 121°C for 20 minutes is the most effective sterilization method. Other methods like dry heat, boiling, filtration and chemicals are used for heat-sensitive items or liquids. Proper monitoring of the sterilization process is important to ensure complete sterilization.
This document provides an overview of cleaning, disinfection and sterilization processes used in healthcare settings. It describes the basic principles and key differences between cleaning, disinfection and sterilization. It outlines the Spaulding classification system for categorizing medical equipment as critical, semi-critical or non-critical to determine the appropriate level of processing required. Examples are provided for each category. Monitoring and documentation of cleaning and sterilization processes are also discussed.
This document discusses sterilization in dentistry. It defines sterilization as the process of destroying all microbial life from surfaces and instruments using physical and chemical methods. Sterilization is important in dentistry to prevent the spread of infections between patients and dental staff through contaminated instruments. Instruments are classified as critical, semi-critical, or non-critical depending on infection risk. Common sterilization methods discussed are heat (dry and moist), radiation, and chemicals. Monitoring of sterilization includes mechanical, chemical, and biological indicators to ensure the process was effective.
The document discusses proper procedures for cleaning and sterilizing dental instruments. It outlines the following key steps: 1) Clean instruments manually or using an ultrasonic cleaner or washer; 2) Dry cleaned instruments with disposable cloth; 3) Package instruments in sterilization wraps; 4) Sterilize using steam, chemical vapor, or dry heat sterilization methods approved for dental use; 5) Store sterilized packaged instruments to maintain sterility. Proper cleaning is essential for effective sterilization.
Sterilization and disinfection are important for preventing transmission of diseases between patients and healthcare professionals. Proper cleaning and use of barriers like gloves and masks are required. Instruments must be properly sterilized depending on their risk category using methods like steam, dry heat, or chemicals. Effectiveness is ensured through biological monitoring. Disinfectants and antiseptics are used to clean surfaces and skin but do not guarantee sterilization. Clinical waste requires appropriate disposal to prevent further contamination.
This document discusses sterilization, disinfection, and infection control procedures for surgical instruments and implants. It covers key topics such as:
- The importance of cleaning instruments before disinfection or sterilization to remove organic materials.
- Categorizing instruments as critical, semi-critical, or non-critical based on infection risk to determine the appropriate level of processing needed.
- Common sterilization methods like steam sterilization, dry heat, and chemical vapor that are used depending on the material.
- Guidelines for disinfecting environmental surfaces and categorizing them based on risk of contamination.
- Recommendations for proper hand hygiene and the use of personal protective equipment to
5.anaesthetic airway equipment and infectionHenok Eshetie
This document provides guidelines on infection control and cleaning of anaesthetic airway equipment. It defines key terms like asepsis, antisepsis, decontamination, disinfection, and sterilization. Cleaning airway equipment involves decontamination, cleaning, and either disinfection or sterilization. Equipment is classified as critical, semi-critical, or non-critical depending on its contact with patients. Proper hand hygiene and cleaning, disinfection or sterilization of equipment after each use is essential to prevent spread of infection. Chlorine solution is commonly used for decontamination, and high-level disinfection or sterilization is recommended for critical equipment.
The document discusses various methods of sterilization used in dentistry. It defines key terms like sterilization, disinfection, asepsis, and provides a brief history of the development of sterilization concepts. It then describes various physical methods of sterilization like heat, filtration, radiation and chemical methods. The major physical methods discussed are dry heat using hot air oven or flaming, moist heat using steam under pressure in an autoclave, and filtration. It provides details on the mechanisms and procedures for each method.
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
Sterilisation and disinfection questionsandrewmidd
The document discusses methods for preventing cross-infection including the use of disposable items, disinfection, and sterilization. It defines these prevention methods and provides examples of vaccines and items that would be considered non-hazardous, hazardous, or special clinical waste. It also addresses procedures for dealing with sharps injuries and identifies items that would be pre-sterilized for use.
This document discusses three common methods of low-temperature sterilization - ethylene oxide, hydrogen peroxide, and ozone. It outlines the basic requirements for any sterilization system including effectiveness, safety, monitoring, and material compatibility. For each method, it describes the sterilization process, key parameters, safety considerations, and methods for monitoring sterilization completion. The document concludes with an overview comparing the main features of the three low-temperature sterilization processes.
Assembly Magazine Sterilizing Medical Devices Requires Friendly AgentsClark W. Houghtling
The best sterilization process for medical devices depends on the materials used. Steam is effective but limits materials that can withstand heat. Ethylene oxide (EO) is friendly to most materials but cannot sterilize liquids or gas-impermeable packages. Nitrogen dioxide damages cellulose, polyurethane, and nylon. Radiation breaks polymer bonds and discolors glass. Material compatibility determines the sterilization method, though switching materials increases costs. Different methods are complementary, with EO accounting for over 50% of sterilization and reducing processing time through new techniques.
EHSxTech Regulatory Highlights: Industrial Hygiene and Occupational HealthAntea Group
Overview of regulations for selected APAC countries covering personal exposure limits, bloodborne pathogens and contagious diseases, indoor air quality, potable water and legionella, and ergonomics.
The document summarizes a study that assessed the impact of ventilation and filtration conditions on particle concentrations in an operating room. It found that before air filter replacement, total particle and viable particle concentrations were high, but decreased significantly after filter replacement. Particle concentrations were lowest in a room with a new air conditioning system. The results showed that poor maintenance of air filters can negatively impact indoor air quality in operating rooms by reducing airflow and increasing particle levels, raising infection risks. However, CO2 levels were not significantly affected by filter replacement. Proper maintenance of ventilation systems through regular filter changes is important for maintaining good indoor air quality in operating rooms.
Occupational exposure limits (OEL) to chemical agents APIs - Quantitative Ris...Azierta
The Occupational Exposure Limit (OEL) is defined as the airborne concentration of a substance (expressed as a weighted average in time for a working day of 8 hours/day and 40 hours/working week) under which it is believed that nearly all workers may be repeatedly exposed (day after day, over a working lifetime) without adverse health effects (ACGIH, 2006; DFG, 2005).
Occupational exposure limits (OELs) are a useful tool to prevent adverse effects on health when managing chemical substances.
On a European scale…
• Employers are legally obliged to provide a work environment that does not threaten the health of the workers (Chemical Agent Directive 98/24/EC and Framework Directive 89/391/EEC).
• Under Directive 89/391/EEC, OELs can be developed nationally, Indicative Occupational Exposure Limit Values (IOELVs).
The history of electrical impedance tomography (EIT) began in the 1980s but it took decades to develop EIT devices suitable for clinical use due to limitations in sensitivity, susceptibility to interference, and lack of user-friendly software. In the early 2000s, a collaboration between researchers and Dräger sought to address these issues and develop the first clinically viable EIT system, culminating in the PulmoVista 500, which enables continuous bedside monitoring of regional lung function without radiation. Validation studies demonstrated EIT's potential for guiding mechanical ventilation and optimizing settings for individual patients with acute lung injury.
The document discusses the history of hygiene practices in hospitals and their role in reducing infection rates. It outlines various sterilization methods used such as autoclaving and highlights the importance of monitoring effective sterilization. The document also discusses the factors that influence infection rates and the methods used for air surveillance in operating theaters, including settle plate counts and slit sampler tests.
1) Hospital pharmacists play an important role in managing medical gas systems in hospitals. They contribute to ensuring proper pharmacological therapies using gases, prevent emergencies, and ensure quality, safety, and cost containment.
2) Pharmacists' competencies in medicinal chemistry and management are key to their role in overseeing medical gas logistics and distribution, quality control testing, staff training, and emergency procedures in compliance with regulations.
3) As the responsible parties for medical gases, pharmacists collaborate with various teams to write procedures, manage risks, store documentation, and provide clinical pharmacy services regarding gases' use in hospitals.
1) Hospital pharmacists play an important role in managing medical gas systems in hospitals. They contribute to ensuring proper pharmacological therapies using gases, prevent emergencies, and ensure quality, safety, and cost containment.
2) Pharmacists' competencies in medicinal chemistry and management are crucial for their role in overseeing medical gas logistics and distribution, quality control testing, staff training, and emergency procedures.
3) Pharmacists are responsible for regulatory compliance, quality assurance of gases from production and distribution systems, proper storage of tanks, and documentation according to various standards and norms.
Setting up ART ,IVF laboratory standards -Artificial Reproductive Technique b...Healthcare consultant
The primary function of an ART laboratory is to provide an optimal environment for gametes and embryos. To set up an ART laboratory, that is efficient and safe, the three key areas to focus on would be the place or location of the laboratory, the embryologists, and the protocols or procedures.
The following chapter will focus on the physical layout of the lab, the basic equipment required and consumables used in the ART lab. The responsibilities of the key people in the laboratory, the embryologists and the importance of the procedures and protocols will be elucidated.
1. Radiation sterilization using gamma rays or high-energy electrons has advantages over other sterilization methods for heat-sensitive and ethylene oxide incompatible pharmaceuticals and polymers. It allows for terminal sterilization of final packaged products and can be done as a batch or continuous process.
2. The minimum accepted radiation dose for sterilization is 2.5 Mrad. Cobalt-60 and cesium-137 are commonly used gamma radiation sources. Electron accelerators can generate electrons from 1-15 MeV for sterilization.
3. Radiation sterilization has benefits over other methods like steam or ethylene oxide sterilization in that it penetrates thoroughly and packaging shelf life
Chapter 9 room ventilation systems (1)Imran Sultan
This chapter discusses ventilation systems in operating rooms. It outlines the goals of OR ventilation which include patient and staff comfort, control of pollutants, ability to regulate temperature and humidity, and control of infections. The key components of an OR ventilation system are ventilation, heating/cooling, humidity control, and waste anesthetic gas scavenging. Recommendations are provided for air changes per hour, directional airflow, filtration and temperature/humidity levels based on studies and guidelines from organizations like ASHRAE and AIA.
Proposal Procedure toDesign AnOptimum Ventilation System For Chemical LaboratoryIJRESJOURNAL
ABSTRACT:This paper aims to provide a proposal for design of an optimum ventilation system for: Good and safe environment,Comfortable workplace for laboratories occupants and Ensure the health of the surrounding environment while minimizing the energy consumption. Concentration level of materials in laboratory is analyzed in correlation with air exchange rate, toxicity and area of laboratory.
Stratasys White Paper - Sterilization of 3D Printed Medical ToolsSUE BROWN
This paper evaluated the sterilization of parts made with 9 different 3D printing materials using 4 sterilization methods: autoclave, ethylene oxide gas, hydrogen peroxide gas plasma, and gamma radiation. Sterility testing found that most materials could be successfully sterilized by all 4 methods. However, autoclaving caused deformations in some materials. This research demonstrates that 3D printed parts can be sterilized for medical applications using appropriate sterilization methods compatible with the materials.
Seminário Nacional do Benzeno ( 5 e 6 dez/12) - Derivação de Limites de Exposição Ocupacional para Substâncias Carcinogênicas e
Mutagênicas - Experiências Internacionais e Nacional
1. The study compared four experimental setups that generate aerosols from nanoparticle powders at different energy levels to understand how system parameters influence test results.
2. Testing two types of TiO2 nanopowders, the study found particle number concentrations and size distributions varied significantly between systems, from 103 to 106 particles/cm3. Results also differed between the hydrophobic and hydrophilic powders.
3. The study proposes using air velocity as a proxy for estimating and comparing energy input levels across different aerosolization systems to improve understanding and standardization of nanoparticle dustiness and deagglomeration testing.
The Central Sterile Supply Department (CSSD) receives, stores, processes, distributes, and controls sterile and non-sterile supplies and equipment for hospitals. It aims to provide safe, sterile supplies and reduce infections. CSSD processes items through cleaning, disinfection, packaging, and sterilization methods like heat, chemicals, or radiation. Proper facility design, staffing, and quality control processes are required for an effective CSSD.
This document discusses methods for monitoring surgical site infections through air sampling in operating theaters. It reviews debates around whether air sampling or conventional swabbing is preferable. The document provides guidelines for effective air sampling, including recommended equipment, placement, sampling duration and volume, and interpretation of results. Counts below 35 colony forming units per cubic meter generally indicate acceptable bacterial levels for conventional surgeries, and below 1 CFU for clean surgeries like joint replacements. Overall it aims to establish best practices for regular air sampling to prevent surgical site infections from airborne microbes in operating theaters.
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Breast cancer: Post menopausal endocrine therapyDr. Sumit KUMAR
Breast cancer in postmenopausal women with hormone receptor-positive (HR+) status is a common and complex condition that necessitates a multifaceted approach to management. HR+ breast cancer means that the cancer cells grow in response to hormones such as estrogen and progesterone. This subtype is prevalent among postmenopausal women and typically exhibits a more indolent course compared to other forms of breast cancer, which allows for a variety of treatment options.
Diagnosis and Staging
The diagnosis of HR+ breast cancer begins with clinical evaluation, imaging, and biopsy. Imaging modalities such as mammography, ultrasound, and MRI help in assessing the extent of the disease. Histopathological examination and immunohistochemical staining of the biopsy sample confirm the diagnosis and hormone receptor status by identifying the presence of estrogen receptors (ER) and progesterone receptors (PR) on the tumor cells.
Staging involves determining the size of the tumor (T), the involvement of regional lymph nodes (N), and the presence of distant metastasis (M). The American Joint Committee on Cancer (AJCC) staging system is commonly used. Accurate staging is critical as it guides treatment decisions.
Treatment Options
Endocrine Therapy
Endocrine therapy is the cornerstone of treatment for HR+ breast cancer in postmenopausal women. The primary goal is to reduce the levels of estrogen or block its effects on cancer cells. Commonly used agents include:
Selective Estrogen Receptor Modulators (SERMs): Tamoxifen is a SERM that binds to estrogen receptors, blocking estrogen from stimulating breast cancer cells. It is effective but may have side effects such as increased risk of endometrial cancer and thromboembolic events.
Aromatase Inhibitors (AIs): These drugs, including anastrozole, letrozole, and exemestane, lower estrogen levels by inhibiting the aromatase enzyme, which converts androgens to estrogen in peripheral tissues. AIs are generally preferred in postmenopausal women due to their efficacy and safety profile compared to tamoxifen.
Selective Estrogen Receptor Downregulators (SERDs): Fulvestrant is a SERD that degrades estrogen receptors and is used in cases where resistance to other endocrine therapies develops.
Combination Therapies
Combining endocrine therapy with other treatments enhances efficacy. Examples include:
Endocrine Therapy with CDK4/6 Inhibitors: Palbociclib, ribociclib, and abemaciclib are CDK4/6 inhibitors that, when combined with endocrine therapy, significantly improve progression-free survival in advanced HR+ breast cancer.
Endocrine Therapy with mTOR Inhibitors: Everolimus, an mTOR inhibitor, can be added to endocrine therapy for patients who have developed resistance to aromatase inhibitors.
Chemotherapy
Chemotherapy is generally reserved for patients with high-risk features, such as large tumor size, high-grade histology, or extensive lymph node involvement. Regimens often include anthracyclines and taxanes.
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The biomechanics of running involves the study of the mechanical principles underlying running movements. It includes the analysis of the running gait cycle, which consists of the stance phase (foot contact to push-off) and the swing phase (foot lift-off to next contact). Key aspects include kinematics (joint angles and movements, stride length and frequency) and kinetics (forces involved in running, including ground reaction and muscle forces). Understanding these factors helps in improving running performance, optimizing technique, and preventing injuries.
“Psychiatry and the Humanities”: An Innovative Course at the University of Mo...Université de Montréal
“Psychiatry and the Humanities”: An Innovative Course at the University of Montreal Expanding the medical model to embrace the humanities. Link: https://www.psychiatrictimes.com/view/-psychiatry-and-the-humanities-an-innovative-course-at-the-university-of-montreal
“Psychiatry and the Humanities”: An Innovative Course at the University of Mo...
Gas plasma sterilization
1. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008
cannot be packaged, sterilized, and stored before use. It also is used when there is insufficient time to
sterilize an item by the preferred package method. Flash sterilization should not be used for reasons of
convenience, as an alternative to purchasing additional instrument sets, or to save time817
. Because of
the potential for serious infections, flash sterilization is not recommended for implantable devices (i.e.,
devices placed into a surgically or naturally formed cavity of the human body); however, flash sterilization
may be unavoidable for some devices (e.g., orthopedic screw, plates). If flash sterilization of an
implantable device is unavoidable, recordkeeping (i.e., load identification, patient’s name/hospital
identifier, and biological indicator result) is essential for epidemiological tracking (e.g., of surgical site
infection, tracing results of biological indicators to patients who received the item to document sterility),
and for an assessment of the reliability of the sterilization process (e.g., evaluation of biological
monitoring records and sterilization maintenance records noting preventive maintenance and repairs with
dates).
Low-Temperature Sterilization Technologies
Ethylene oxide (ETO) has been widely used as a low-temperature sterilant since the 1950s. It
has been the most commonly used process for sterilizing temperature- and moisture-sensitive medical
devices and supplies in healthcare institutions in the United States. Two types of ETO sterilizers are
available, mixed gas and 100% ETO. Until 1995, ethylene oxide sterilizers combined ETO with a
chloroflourocarbon (CFC) stabilizing agent, most commonly in a ratio of 12% ETO mixed with 88% CFC
(referred to as 12/88 ETO).
For several reasons, healthcare personnel have been exploring the use of new low-temperature
sterilization technologies
825, 851
. First, CFCs were phased out in December 1995 under provisions of the
Clean Air Act 852
. CFCs were classified as a Class I substance under the Clean Air Act because of
scientific evidence linking them to destruction of the earth’s ozone layer. Second, some states (e.g.,
California, New York, Michigan) require the use of ETO abatement technology to reduce the amount of
ETO being released into ambient air from 90 to 99.9% depending on the state. Third, OSHA regulates
the acceptable vapor levels of ETO (i.e., 1 ppm averaged over 8 hours) due to concerns that ETO
exposure represents an occupational hazard318
. These constraints have led to the development of
alternative technologies for low-temperature sterilization in the healthcare setting.
Alternative technologies to ETO with chlorofluorocarbon that are currently available and cleared
by the FDA for medical equipment include 100% ETO; ETO with a different stabilizing gas, such as
carbon dioxide or hydrochlorofluorocarbons (HCFC); immersion in peracetic acid; hydrogen peroxide gas
plasma; and ozone. Technologies under development for use in healthcare facilities, but not cleared by
the FDA, include vaporized hydrogen peroxide, vapor phase peracetic acid, gaseous chlorine dioxide,
ionizing radiation, or pulsed light
400, 758, 853
. However, there is no guarantee that these new sterilization
technologies will receive FDA clearance for use in healthcare facilities.
These new technologies should be compared against the characteristics of an ideal low-
temperature (<60o
C) sterilant (Table 9). 851
While it is apparent that all technologies will have limitations
(Table 9), understanding the limitations imposed by restrictive device designs (e.g., long, narrow lumens)
is critical for proper application of new sterilization technology854
. For example, the development of
increasingly small and complex endoscopes presents a difficult challenge for current sterilization
processes. This occurs because microorganisms must be in direct contact with the sterilant for
inactivation to occur. Several peer-reviewed scientific publications have data demonstrating concerns
about the efficacy of several of the low-temperature sterilization processes (i.e., gas plasma, vaporized
hydrogen peroxide, ETO, peracetic acid), particularly when the test organisms are challenged in the
presence of serum and salt and a narrow lumen vehicle469, 721, 825, 855, 856
. Factors shown to affect the
efficacy of sterilization are shown in Table 10.
Ethylene Oxide "Gas" Sterilization
Overview. ETO is a colorless gas that is flammable and explosive. The four essential
61
2. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008
parameters (operational ranges) are: gas concentration (450 to 1200 mg/l); temperature (37 to 63o
C);
relative humidity (40 to 80%)(water molecules carry ETO to reactive sites); and exposure time (1 to 6
hours). These influence the effectiveness of ETO sterilization814, 857, 858
. Within certain limitations, an
increase in gas concentration and temperature may shorten the time necessary for achieving sterilization.
The main disadvantages associated with ETO are the lengthy cycle time, the cost, and its
potential hazards to patients and staff; the main advantage is that it can sterilize heat- or moisture-
sensitive medical equipment without deleterious effects on the material used in the medical devices
(Table 6). Acute exposure to ETO may result in irritation (e.g., to skin, eyes, gastrointestinal or
respiratory tracts) and central nervous system depression859-862
. Chronic inhalation has been linked to
the formation of cataracts, cognitive impairment, neurologic dysfunction, and disabling
polyneuropathies860, 861, 863-866
. Occupational exposure in healthcare facilities has been linked to
hematologic changes 867
and an increased risk of spontaneous abortions and various cancers318, 868-870
.
ETO should be considered a known human carcinogen871
.
The basic ETO sterilization cycle consists of five stages (i.e., preconditioning and humidification,
gas introduction, exposure, evacuation, and air washes) and takes approximately 2 1/2 hrs excluding
aeration time. Mechanical aeration for 8 to 12 hours at 50 to 60o
C allows desorption of the toxic ETO
residual contained in exposed absorbent materials. Most modern ETO sterilizers combine sterilization
and aeration in the same chamber as a continuous process. These ETO models minimize potential ETO
exposure during door opening and load transfer to the aerator. Ambient room aeration also will achieve
desorption of the toxic ETO but requires 7 days at 20o
C. There are no federal regulations for ETO
sterilizer emission; however, many states have promulgated emission-control regulations814
.
The use of ETO evolved when few alternatives existed for sterilizing heat- and moisture-sensitive
medical devices; however, favorable properties (Table 6) account for its continued widespread use872
.
Two ETO gas mixtures are available to replace ETO-chlorofluorocarbon (CFC) mixtures for large
capacity, tank-supplied sterilizers. The ETO-carbon dioxide (CO2) mixture consists of 8.5% ETO and
91.5% CO2. This mixture is less expensive than ETO-hydrochlorofluorocarbons (HCFC), but a
disadvantage is the need for pressure vessels rated for steam sterilization, because higher pressures
(28-psi gauge) are required. The other mixture, which is a drop-in CFC replacement, is ETO mixed with
HCFC. HCFCs are approximately 50-fold less damaging to the earth’s ozone layer than are CFCs. The
EPA will begin regulation of HCFC in the year 2015 and will terminate production in the year 2030. Two
companies provide ETO-HCFC mixtures as drop-in replacement for CFC-12; one mixture consists of
8.6% ETO and 91.4% HCFC, and the other mixture is composed of 10% ETO and 90% HCFC872
. An
alternative to the pressurized mixed gas ETO systems is 100% ETO. The 100% ETO sterilizers using
unit-dose cartridges eliminate the need for external tanks.
ETO is absorbed by many materials. For this reason, following sterilization the item must
undergo aeration to remove residual ETO. Guidelines have been promulgated regarding allowable ETO
limits for devices that depend on how the device is used, how often, and how long in order to pose a
minimal risk to patients in normal product use814
.
ETO toxicity has been established in a variety of animals. Exposure to ETO can cause eye pain,
sore throat, difficulty breathing and blurred vision. Exposure can also cause dizziness, nausea,
headache, convulsions, blisters and vomiting and coughing873
. In a variety of in vitro and animal studies,
ETO has been demonstrated to be carcinogenic. ETO has been linked to spontaneous abortion, genetic
damage, nerve damage, peripheral paralysis, muscle weakness, and impaired thinking and memory873
.
Occupational exposure in healthcare facilities has been linked to an increased risk of spontaneous
abortions and various cancers318
. Injuries (e.g., tissue burns) to patients have been associated with ETO
residues in implants used in surgical procedures874
. Residual ETO in capillary flow dialysis membranes
has been shown to be neurotoxic in vitro875
. OSHA has established a PEL of 1 ppm airborne ETO in the
workplace, expressed as a TWA for an 8-hour work shift in a 40-hour work week. The “action level” for
ETO is 0.5 ppm, expressed as an 8-hour TWA, and the short-term excursion limit is 5 ppm, expressed as
62
3. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008
a 15-minute TWA814
. For details of the requirements in OSHA’s ETO standard for occupational
exposures, see Title 29 of the Code of Federal Regulations (CFR) Part 1910.1047873
. Several personnel
monitoring methods (e.g., charcoal tubes and passive sampling devices) are in use814
. OSHA has
established a PEL of 5 ppm for ethylene chlorohydrin (a toxic by-product of ETO) in the workplace876
.
Additional information regarding use of ETO in health care facilities is available from NIOSH.
Mode of Action. The microbicidal activity of ETO is considered to be the result of alkylation of
protein, DNA, and RNA. Alkylation, or the replacement of a hydrogen atom with an alkyl group, within
cells prevents normal cellular metabolism and replication877
.
Microbicidal Activity. The excellent microbicidal activity of ETO has been demonstrated in
several studies 469, 721, 722, 856, 878, 879
and summarized in published reports877
. ETO inactivates all
microorganisms although bacterial spores (especially B. atrophaeus) are more resistant than other
microorganisms. For this reason B. atrophaeus is the recommended biological indicator.
Like all sterilization processes, the effectiveness of ETO sterilization can be altered by lumen
length, lumen diameter, inorganic salts, and organic materials469, 721, 722, 855, 856, 879
. For example, although
ETO is not used commonly for reprocessing endoscopes28
, several studies have shown failure of ETO in
inactivating contaminating spores in endoscope channels 855
or lumen test units 469, 721, 879
and residual
ETO levels averaging 66.2 ppm even after the standard degassing time456
. Failure of ETO also has been
observed when dental handpieces were contaminated with Streptococcus mutans and exposed to
ETO880
. It is recommended that dental handpieces be steam sterilized.
Uses. ETO is used in healthcare facilities to sterilize critical items (and sometimes semicritical
items) that are moisture or heat sensitive and cannot be sterilized by steam sterilization.
Hydrogen Peroxide Gas Plasma
Overview. New sterilization technology based on plasma was patented in 1987 and marketed in
the United States in 1993. Gas plasmas have been referred to as the fourth state of matter (i.e., liquids,
solids, gases, and gas plasmas). Gas plasmas are generated in an enclosed chamber under deep
vacuum using radio frequency or microwave energy to excite the gas molecules and produce charged
particles, many of which are in the form of free radicals. A free radical is an atom with an unpaired
electron and is a highly reactive species. The proposed mechanism of action of this device is the
production of free radicals within a plasma field that are capable of interacting with essential cell
components (e.g., enzymes, nucleic acids) and thereby disrupt the metabolism of microorganisms. The
type of seed gas used and the depth of the vacuum are two important variables that can determine the
effectiveness of this process.
In the late 1980s the first hydrogen peroxide gas plasma system for sterilization of medical and
surgical devices was field-tested. According to the manufacturer, the sterilization chamber is evacuated
and hydrogen peroxide solution is injected from a cassette and is vaporized in the sterilization chamber to
a concentration of 6 mg/l. The hydrogen peroxide vapor diffuses through the chamber (50 minutes),
exposes all surfaces of the load to the sterilant, and initiates the inactivation of microorganisms. An
electrical field created by a radio frequency is applied to the chamber to create a gas plasma.
Microbicidal free radicals (e.g., hydroxyl and hydroperoxyl) are generated in the plasma. The excess gas
is removed and in the final stage (i.e., vent) of the process the sterilization chamber is returned to
atmospheric pressure by introduction of high-efficiency filtered air. The by-products of the cycle (e.g.,
water vapor, oxygen) are nontoxic and eliminate the need for aeration. Thus, the sterilized materials can
be handled safely, either for immediate use or storage. The process operates in the range of 37-44
o
C
and has a cycle time of 75 minutes. If any moisture is present on the objects the vacuum will not be
achieved and the cycle aborts856, 881-883
.
A newer version of the unit improves sterilizer efficacy by using two cycles with a hydrogen
63
4. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008
peroxide diffusion stage and a plasma stage per sterilization cycle. This revision, which is achieved by a
software modification, reduces total processing time from 73 to 52 minutes. The manufacturer believes
that the enhanced activity obtained with this system is due in part to the pressure changes that occur
during the injection and diffusion phases of the process and to the fact that the process consists of two
equal and consecutive half cycles, each with a separate injection of hydrogen peroxide. 856, 884, 885
This
system and a smaller version 400, 882
have received FDA 510[k] clearance with limited application for
sterilization of medical devices (Table 6). The biological indicator used with this system is Bacillus
atrophaeus spores851
. The newest version of the unit, which employs a new vaporization system that
removes most of the water from the hydrogen peroxide, has a cycle time from 28-38 minutes (see
manufacturer’s literature for device dimension restrictions).
Penetration of hydrogen peroxide vapor into long or narrow lumens has been addressed outside
the United States by the use of a diffusion enhancer. This is a small, breakable glass ampoule of
concentrated hydrogen peroxide (50%) with an elastic connector that is inserted into the device lumen
and crushed immediately before sterilization470, 885
. The diffusion enhancer has been shown to sterilize
bronchoscopes contaminated with Mycobacteria tuberculosis886
. At the present time, the diffusion
enhancer is not FDA cleared.
Another gas plasma system, which differs from the above in several important ways, including
the use of peracetic acid-acetic acid-hydrogen peroxide vapor, was removed from the marketplace
because of reports of corneal destruction to patients when ophthalmic surgery instruments had been
processed in the sterilizer887, 888
. In this investigation, exposure of potentially wet ophthalmologic surgical
instruments with small bores and brass components to the plasma gas led to degradation of the brass to
copper and zinc888, 889
. The experimenters showed that when rabbit eyes were exposed to the rinsates of
the gas plasma-sterilized instruments, corneal decompensation was documented. This toxicity is highly
unlikely with the hydrogen peroxide gas plasma process since a toxic, soluble form of copper would not
form (LA Feldman, written communication, April 1998).
Mode of Action. This process inactivates microorganisms primarily by the combined use of
hydrogen peroxide gas and the generation of free radicals (hydroxyl and hydroproxyl free radicals) during
the plasma phase of the cycle.
Microbicidal Activity. This process has the ability to inactivate a broad range of
microorganisms, including resistant bacterial spores. Studies have been conducted against vegetative
bacteria (including mycobacteria), yeasts, fungi, viruses, and bacterial spores
469, 721, 856, 881-883, 890-893
. Like
all sterilization processes, the effectiveness can be altered by lumen length, lumen diameter, inorganic
salts, and organic materials469, 721, 855, 856, 890, 891, 893
.
Uses. Materials and devices that cannot tolerate high temperatures and humidity, such as some
plastics, electrical devices, and corrosion-susceptible metal alloys, can be sterilized by hydrogen
peroxide gas plasma. This method has been compatible with most (>95%) medical devices and
materials tested884, 894, 895
.
Peracetic Acid Sterilization
Overview. Peracetic acid is a highly biocidal oxidizer that maintains its efficacy in the presence
of organic soil. Peracetic acid removes surface contaminants (primarily protein) on endoscopic tubing711,
717
. An automated machine using peracetic acid to sterilize medical, surgical, and dental instruments
chemically (e.g., endoscopes, arthroscopes) was introduced in 1988. This microprocessor-controlled,
low-temperature sterilization method is commonly used in the United States107
. The sterilant, 35%
peracetic acid, and an anticorrosive agent are supplied in a single-dose container. The container is
punctured at the time of use, immediately prior to closing the lid and initiating the cycle. The
concentrated peracetic acid is diluted to 0.2% with filtered water (0.2 μm) at a temperature of
approximately 50o
C. The diluted peracetic acid is circulated within the chamber of the machine and
64