Hastahane denetleme kriterleri
Hastanelerde hijyenin sağlanması için temel kriterler
Birincil ve ikincil derecede enfeksiyon kaynakları ve nedenleri-mikro organizmalar
Enfeksiyon kaynaklarının başlangıcı ve kontaminasyona yol açması
Dezenfektanların kullanımı
Dezenfektan seçimi dikkate alınması gereken AFNOR, NF ve EN standartları parametreleri.
Dezenfeksiyon ve temizlik için kullanılan maddelerin kimyasal içerikleri-çalışma alanı pH’sı
Kirliliğin çözümlenmesi ve tasnif çeşitleri
pH’sı benzerlik gösteren maddelerin seçimi
Ürün temizliğini oluşturan Physico-chemical unsurlar
Ürün uygunsuzluğu
Temizlik parametreleri
Hasta odalarında temizlik metotları
Ekipman, temizlik ve dezenfeksiyon prosedürleri organizasyonu
Gıda bulunan yerlerin hijyeni
Gıda bulunan yerler için genel kurallar
Bakterioloji-Personel hijyeni
Zeminlerin cilalanması ve korunması
Profesyonel ekipmanların bakımı ve kullanımı
Vantilasyon ve klima sistemleri hijyen ve sanitasyonu
3.14 Workshop 4
Treatment and disposal options
A) For participants from national or local authorities
Evaluate the treatment and disposal options that would be suitable for health-care waste in your country and prepare a policy. Differentiate the policy for large hospitals and for smaller, remote health-care establishments. Take into account the aspects listed below.
B) For participants from health-care establishments
Evaluate the treatment and disposal options that would be suitable for health-care waste in your health-care establishment and propose a strategy. Formulate a strategy for larger hospitals and smaller, remote health-care establishments. Take into account the following aspects:
C Public health and safety, including workers safety
C Existing options in the country/ region
C Different health-care waste categories
C Availability of qualified personnel
C Technologies available on the market
C Environmental aspects
C Approximate investment and operational costs
C Required training to operate the technologies
C Maintenance requirements
C On-site versus off-site options
C Acceptability by the general public
etc.
3.15 Lecture 10
Wastewater management
Overheads
Overhead 10.1 Wastewater from health-care establishments
Overhead 10.2 Wastewater discharge to municipal sewer
Overhead 10.3 On-site treatment of Wastewater
Overhead 10.4 On-site sludge treatment
Overhead 10.5 On-site minimal safety requirements
Overhead 10.6 Sanitation in health-care establishments
Teachers notes
Handouts
Reduced overheads
Teachers notes - Lecture 10
Overhead 10.1
Sewage from health-care establishments is of a quality similar to urban sewage, but may in addition include various potentially hazardous components, listed on the overhead.
Of main concern are Wastewater with a high content of enteric pathogens easily transmitted through the water cycle; these are produced by wards treating patients with enteric diseases (mainly contained in patients excreta), in particular during outbreaks of diarrhoeal disease.
Possible links between unsafe Wastewater disposal of health-care establishments have been strongly suspected in relation to major outbreak spreads (e.g. cholera outbreaks).
Sewer networks of the health-care establishments are not always connected to an efficiently operated sewage treatment plant, and sometimes municipal sewer networks may not even exist.
Overhead 10.2
Discharge to the municipal sewer is possible if the health-care waste management system of the establishment reaches high standards, ensuring the absence of significant quantities of toxic chemicals, pharmaceuticals and radionuclides, and cytotoxic drugs and antibiotics in the discharged sewage; also, in oncological wards, excreta from patients under treatment with cytotoxic drugs should be collected separately and adequately treated as the other cytotoxic waste.
Chemical pollutants contained in hospital Wastewater may have toxic effects on the active bacteria of the municipal sewage purification processes, which may cause a problem regarding the good functioning of the sewage treatment plant.
Overhead 10.3
Many hospitals have their own sewage treatment plant, in particular when the hospital is not connected to any municipal treatment plants. Efficient treatment of sewage from health-care establishments should include the operations outlined on the overhead.
Secondary treatment will usually remove a significant part of helminths, bacteria and viruses. Tertiary treatment should reduce the suspended organic matter to far less than 10 mg/l. For reaching pathogen concentrations comparable to those found in natural waters, chlorine disinfection should be made.
Overhead 10.4
The sludge resulting from hospital sewage treatment will contain high concentrations of helminths and other pathogens.
Reuse of Wastewater and sludges in agriculture and aquaculture:
According to the relevant WHO guidelines, the treated Wastewater should not contain more than one helminth egg per litre and no more than 1000 faecal coliforms per 100 millilitres for unrestricted irrigation. It is essential that the treated sludge does not contain more than one helminth egg per kilogram and no more than 1000 faecal coliforms per 100 grams. Furthermore, the sludge should be applied to the fields in trenches and covered with soil.
Overhead 10.5
There is no safe solution for the disposal of sewage from hospitals, which are not connected to a sewer, are unable to afford a compact sewage treatment plant, and have no space available to build a lagooning system.
Establishments, which cannot afford sewage treatment plants, should use a lagooning system. The lagooning system should comprise two successive lagoons to achieve an acceptable level of purification of their hospital sewage. Thislagooning system may eventually be followed by land infiltration of the effluent to benefit from the soil filtrating capacity.
Minimal safety requirements should be taken by establishments with minimal programmes, unable to afford any sewage treatment to minimise health risks (see overhead).
Small-scale rural health-care establishments applying minimal waste management programmes may discharge their Wastewater to the environment. An acceptable solution would be to practice natural filtration of their sewage through infiltration on adequate porous soils, located outside the catchment area of aquifers used to produce drinking water or to supply water to the hospital.
Overhead 10.6
In many of the health-care establishments of developing countries, patients have no access to sanitation. This means that excreta are usually spread out to the environment, creating a high risk of infection to people who come in direct or indirect contact with it. Human excreta are the principal vehicles for the transmission and spread of a wide range of communicable diseases. It is, therefore, of primary importance to provide access to adequate sanitation in every health-care establishment. The faecal-oral cycle (and other routes of transmission like penetration through the skin) has to be interrupted to avoid the diseases being continuously recirculated through the population.
The health-care establishment should, if possible, be connected to a sewage system. There also exist technically sound on-site sanitation systems according to the standard technologies in sanitary engineering, which are readily accessible in guidebooks. In addition, convenient washing facilities should be available to all patients’ personnel and visitors.
3.16 Lecture 11
Workers health and safety and emergencies
Overheads
Overhead 11.1 Workers health and safety - principles
Overhead 11.2 Personal hygiene
Overhead 11.3 Protective clothing
Overhead 11.4 Safe management practices
Overhead 11.5 Programme for response to injuries
Overhead 11.6 Cytotoxic safety
Overhead 11.7 Emergency response - principles
Overhead 11.8 Procedure for spillage cleaning
Overhead 11.9 Reporting incidents
Teacher’s notes
Handouts
Reduced overheads
Teacher’s notes - Lecture 11
Overhead 11.1
Health and safety training should ensure that workers know and understand the potential risks associated with health-care waste, the value of immunisation, and the importance of using the personal protective equipment and personal hygiene.
Groups of workers at risk include health-care providers, hospital cleaners, maintenance workers, operators of treatment facilities, health-care waste handlers and health-care waste disposal operators in and outside health-care establishments.
Overhead 11.2
Personal hygiene, in particular hand washing, may prevent further spread of pathogens (e.g. ingestion) with which the worker may have come into contact.
Overhead 11.3
The protective clothing listed on the overhead should be used by workers handling health-care waste (only the disposable gloves are for use by medical staff). The overall, aprons, leg protectors or industrial boots and gloves are obligatory, while the use of the other items should depend upon the operations carried out by the worker.
Protective clothing is essential to protect against personal injury.
Overhead 11.4
Many of the practices outlined in the previous lectures of this course contribute to workers’ safety and health protection. The main points are listed on the overhead.
Segregation and waste identification shows the hazards of the content.
Adequate packaging and transportation prevents exposure of workers to the content.
Adequate storage limits the access to unauthorized persons and the access of rodents.
Overhead 11.5
A programme should be established for the response to injuries of personnel. This programme should be known to all staff. It should include the elements listed on the overhead.
Identifying the source of injury may provide information on possible infections.
Assessing the detailed circumstances of the injury and its causes may suggest measures for the prevention of such accidents in the future.
Overhead 11.6
Due to the special hazards related to exposure to cytotoxic products, special precautions should be taken.
Rural or urban district hospitals of middle and lower income countries do not typically use cytotoxic products.
Overhead 11.7
One person should be designated to be responsible for handling emergencies. This persons has to design a deputy in case of absence.
In health-care establishments the most common emergencies are probably related to the spill of infectious and hazardous substances and wastes. The response to emergencies is based on the principles listed on the overhead.
Staff should be trained for emergency procedures. Written procedures should be established for the different types of emergencies. The necessary tools and materials should be easily accessible at all times.
Overhead 11.8
Usually, spills only require cleaning of the contaminated area. For spills of infectious agents, it may be necessary to evacuate the area, depending on the infectious agents involved. On the overhead is listed an example of procedure to follow after a spill. The actions should follow the order provided on the overhead.
It is essential that contaminated eyes or skin are decontaminated immediately, in general with abundant amounts of water.
Overhead 11.9
The incidents should be reported to the responsible officer who should investigate them. This officer should consider the implementation of preventive measures.
3.17 Lecture 12
Waste management related costs
Overheads
Overhead 12.1 Principles of costing
Overhead 12.2 Internal and external costs
Overhead 12.3 Total costs of a waste management system
Overhead 12.4 Methods of financing
Overhead 12.5 Use of private services
Overhead 12.6 Contractual arrangements
Overhead 12.7 Cost reduction check list
Teacher’s notes
Lecture Handout
Handout 12.1 Costs of construction and operation of a health-care waste incineration plant
Reduced overheads
Teacher’s notes - Lecture 12
Overhead 12.1
According to the Polluter pays principle, each health-care establishment should pay for the safe treatment and disposal of the waste it generates.
Before planning a waste management system it should always ensure that the waste is segregated, which will significantly reduce the quantities of hazardous waste requiring special handling, treatment and disposal.
Adequate sizing of all elements of the system will prevent from subsequent costly modifications;
Future trends in waste production, and the legislation becoming more stringent, should be anticipated.
Overhead 12.2
The construction, operation and maintenance costs of health-care waste management systems can represent a significant part of the global budget of a health-care establishment. It is essential to consider these costs when planning an establishment.
The internal and external costs of waste management have to be considered by the health-care establishment.
Overhead 12.3
A list of elements that contribute to the costs related to health-care waste management is summarised on Handout 12.1, for the example of an incinerator. It can be adapted for other technologies. This list may not be exhaustive.
Overhead 12.4
For public health-care establishments, general revenues may be used for waste management. The treatment and disposal facilities/sites may be constructed and operated from public or private funding. The national authority may require, by regulations, implementation of on-site treatment, compulsorily use public facilities or allow the choice to use private waste facilities (e.g. in the USA). These regulations may restrict certain disposal options or specify the required treatment technology and standards of operation.
Under arrangements with a private company, a private entity finances, builds, owns and operates for instance the treatment facility and sells the services to health-care establishments for collection and disposal fees. The use of private services should be encouraged, in particular for alternative treatment methods other than incineration.
Overhead 12.5
On the overhead are listed possible advantages and disadvantages that may result from the use of private waste management services including treatment and disposal. The main advantage is usually the increased efficiency resulting from competition among service providers on the market.
The reduced level of services refers specifically to reliability, safety, public health risks and environmental aspects.
Also, the private company may increase the service costs due to factors that could not be foreseen (e.g. change of legislation) and which will represent unexpected expenses for the health-care establishment.
Overhead 12.7
Cost reduction measures can be taken at different levels of waste management.
As repeatedly mentioned, the most efficient ways to minimise hazardous health-care waste production are segregation, minimisation, in certain cases recycling of wastes, purchase policies and stock management.
Documentation of costs will allow to identify priorities for cost reduction and monitor progress in the achievements of objectives.
Handout 12.1:Costs of construction and operation of a health-care waste incineration plant
Site
Cost of land
Rights of way
Site preparation and infrastructure
Provision of utilities to site
Consultancy fees
Environmental/waste management consultant
Engineering
Architectural
Legal fees
Construction costs
Incinerator building
Waste storage room
Offices
Incinerator
Cost of incinerator
Freight and storage charges
Waste transport costs
Waste collection trucks
Bins/containers for transporting waste from hospitals to incinerator site
Equipment costs
Trolleys for collecting waste bags from wards
Bag holders to be located at all sources of waste arisings in hospitals
Weighing machines for weighing waste bags
Refrigerators for storage of waste if necessary
Financing charges
Interest
Taxes
Accounting and audit fees
Direct operating costs
Manpower requirements (manager, operators, drivers,...)
Yellow bags with tags for infectious wastes
Black bags for non-risk waste
Sharps containers
Transportation costs
Utilities (fuel, water, electricity)
Chemicals (for flue-gas cleaning)
Indirect operating costs
Training
Incinerator maintenance and parts replacement
Vehicle maintenance
Uniforms and safety equipment
Ash disposal cost
Compliance monitoring of flue gas emissions
Project management and administrative costs for the organisation responsible for the execution and long-term operation of the project
Estimation of Costs
Total
3.18 Lecture 13
Training on HCW management
Overheads
Overhead 13.1 Aims of education and training
Overhead 13.2 Target groups for training
Overhead 13.3 Training programme content
Overhead 13.4 Training for waste management operators
Overhead 13.5 Training for waste transporters
Overhead 13.6 Training for operators of waste treatment facilities
Overhead 13.7 Training for landfill operators
Teacher’s notes
Handouts
Reduced overheads
Teacher’s notes - Lecture 13
Overhead 13.1
Personnel of health-care establishments and waste workers have a right to be informed about the potential hazards of the waste they are handling. Training of personnel and workers are the basis for an effective implementation of the waste management strategy. Raising their awareness is a way forward towards gaining their cooperation. The overall aim of the training is to develop awareness in the participants of the health, safety and environmental protection issues relating to healthcare waste, and how these can affect them in their daily work.
Overhead 13.2
All personnel should be trained on the management strategy of the establishment. Actions need to be taken at management level, of those producing the waste, and those handling the waste. Separate courses should be designed for the categories listed on the overhead, specifically adapted to their tasks, responsibilities and level of education.
Overhead 13.3
The Infection Control Officer would usually be a suitable person to be responsible for training. For smaller health-care establishments, a central training function could be established by the regional authority. Training packages could also be developed by national government agencies.
A training package should include numerous illustrations, such as drawings, figure and photographs of local applications.
The ideal number of participants is 20 to 30.
Overhead 13.4
The overhead contains a number of issues to be addressed for the training of waste management operators. These are the minimal training requirements.
Overhead 13.5
These are the main areas which should be addressed in the training course. The waste may be transported by the health-care establishment, or it may contract an authorised waste transporter.
Overhead 13.6
These are the main areas which should be addressed in the training course.
The competence of the trainee should be assessed by carrying out actual or simulated activities that have been taught in the training session to ensure that the individuals can carry out the required tasks correctly.
Overhead 13.7
Safe burying of hazardous health-care waste will continue to be practiced in many locations, until sufficient capacity for adequate treatment will be available. The training of landfill operators is important for limiting the subsequent risks, mainly related to scavenging and the quality of surface and groundwater. The competence of the trainee should be assessed.
3.19 Workshop 5
Regulatory package/ Waste management plan - design
Two groups should be established for this workshop. Participants from authorities may mainly join the group A, and participants from health-care establishments group B. It may however be enriching if group A also contains participants from group B and vice versa.
A) Draft an outline of a regulatory package for national legislation on health-care waste management
Draft the structure of the national regulatory package (e.g. policy, law, guidelines); draft the main elements to be included in the regulatory documents.
B) Design a comprehensive waste management plan for a large hospital, and one for a smaller, remote establishment, taking into account the following aspects:
C Organisation and responsibilities
C On-site waste management
C Waste treatment and disposal
C Wastewater management
C Workers’ health and safety
C Training
You may use the elements already elaborated during the previous workshops. An overview for an establishment practising a minimal programme for waste management, e.g. a smaller remote establishments, is provided in the Handout for Workshop 5 and may assist you in your work.
The main results of the workshops should be written on transparencies or a blackboard and reported to the entire group after about 1 hour. The results, and the compatibility between the material elaborated by the two groups, should be discussed in plenary.
3.20 Sources of handouts
Christen J/SKAT. Dar es Salaam Urban Health Project. Health care waste management in district health facilities. Situational Analysis and system development. Swiss Centre for Development Cooperation in Technology and Management St Gallen, Switzerland, 1996.
Dunsmore DJ. Safety measures for use in outbreaks of communicable disease. Geneva, Switzerland, World Health Organization, 1986.
WHO. Action Plan for the development of national programme for sound management of hospital wastes. An outcome of the Regional Consultation on Sound Management of Hospital Waste, Chiang Mai, Thailand, 28-29 November 1996. New Delhi, India, World Health Organization, Regional Office for South-East Asia, 1997.
WHO. Regional Guidelines for Health Care Waste Management in Developing Countries (draft), Working document used at the WHO Regional Workshop on Clinical Waste Management. 28 November - 2 December 1994. Kuala Lumpur, Malaysia, World Health Organization, Western Pacific Regional Environmental Health Centre (EHC), 1994.
The Processing of Instruments and Materials in Hospitals and General Practice
These recommendations are intended to assist in the practical and safe organization of instrument processing. In some cases, the technological requirements of the recommendations have not yet been established. The development of the appropriate technology is therefore an immediate goal.
The aim of standardized processing is the quality assurance of disinfected and sterilized goods (medical devices). This serves to protect both the patient and medical staff from the risk of infection and to preserve the serviceability of medical instruments and equipment. Instrument processing encompasses the various steps in the cycle from initial use to renewed supply including:
The aim of standardized processing is the quality assurance of disinfected and sterilized goods (medical devices). This serves to protect both the patient and medical staff from the risk of infection and to preserve the serviceability of medical instruments and equipment. Instrument processing encompasses the various steps in the cycle from initial use to renewed supply including:
· disposal
· cleaning and disinfection
· inspection, maintenance and sorting
Disinfection goods
· packaging
· supply
· storage
Sterilization goods
· packaging
· sterilization
· supply
· storage
A medical device intended for reprocessing should be brought from its place of use to the sterilization facility in a dry condition.
For medical staff, the highest possible degree of protection from infection is achieved when instruments are cleaned and thermally disinfected in automated machines using validated procedures. In order to operate automated equipment at full capacity, it is preferable to situate the equipment in a central location. Factors such as the system used for transporting contaminated instruments, the use of chemicals, water quality and other relevant factors must be matched to suit the automated process employed.
Cleaning and disinfection equipment should be checked regularly: this requires that testing is carried out at least once every six months. Testing should be carried out using quantitative biological methods in conjunction with physical and chemical procedures to measure the critical parameters. Manual cleaning and disinfection should be limited to exceptional cases.
For medical staff, the highest possible degree of protection from infection is achieved when instruments are cleaned and thermally disinfected in automated machines using validated procedures. In order to operate automated equipment at full capacity, it is preferable to situate the equipment in a central location. Factors such as the system used for transporting contaminated instruments, the use of chemicals, water quality and other relevant factors must be matched to suit the automated process employed.
Cleaning and disinfection equipment should be checked regularly: this requires that testing is carried out at least once every six months. Testing should be carried out using quantitative biological methods in conjunction with physical and chemical procedures to measure the critical parameters. Manual cleaning and disinfection should be limited to exceptional cases.
1. Disinfection Goods
Disinfection goods are items of medical equipment which are to be used on patients following mechanical cleaning and disinfection. Examples include anesthetic and endoscopic equipment and accessories. It is recommended that disinfection goods are packaged in order to prevent contamination during storage.
2. Sterilization Goods
Sterilization leads to the killing of microorganisms (including bacterial spores) and the irreversible inactivation of viruses, both on and within the object being sterilized. “Sterile” can therefore be defined as being free from viable microorganisms.
However, sterility can only be reached within a defined probability. Sterilization procedures must secure a reduction in microorganism numbers by 6 lg units, i.e. a reduction to one millionth of the initial count. According to DIN EN 556, a medical device can only be defined as sterile when the theoretical probability of contamination is less than one in one million. In order to guarantee the effective sterilization of a diverse range of medical goods through the application of the appropriate sterilization procedure, a list of specific items of equipment suitable for a specific sterilization procedure (as already existing for plasma sterilization) is desirable.
The probability of contamination occurring is dependent not only upon sterilization procedures but also upon the initial germ count (bioburden) on the medical device.
Standardized cleaning and disinfection procedures should be seen as a precondition to safe sterilization.
However, sterility can only be reached within a defined probability. Sterilization procedures must secure a reduction in microorganism numbers by 6 lg units, i.e. a reduction to one millionth of the initial count. According to DIN EN 556, a medical device can only be defined as sterile when the theoretical probability of contamination is less than one in one million. In order to guarantee the effective sterilization of a diverse range of medical goods through the application of the appropriate sterilization procedure, a list of specific items of equipment suitable for a specific sterilization procedure (as already existing for plasma sterilization) is desirable.
The probability of contamination occurring is dependent not only upon sterilization procedures but also upon the initial germ count (bioburden) on the medical device.
Standardized cleaning and disinfection procedures should be seen as a precondition to safe sterilization.
2.1 Sterile device packaging
The packaging used during sterilization must not hinder the sterilization process and it must maintain the sterilized condition of the object without impeding unpacking and subsequent use. Of the various forms of packaging listed in norms and standards, the following are recommended:
· rigid aluminum containers
· peel pouches (paper/transparent plastic combinations)
· sterilization paper.
Sterile containers made of stainless steel are not recommended due to their heavy weight and relatively high thermal inertia. With the exception of using textile covers for instrument trays in containers, textile towels as well as plastic roll packaging are not suitable as sterilization packaging materials. The type of packaging (single-use, filter container or vent container) must be matched to suit the sterilization procedure employed. Containers with single-use (disposable) paper filters and large lids – to enhance surface area and therefore facilitate air drying – are recommended.
Aluminum containers can be damaged by chemi-cal disinfectants; for this reason, they cannot be immersed in disinfectant solution, a method employed during transport of used instruments which has become obsolete anyway. Where lidded containers fitted with vents or filters are employed, the condition of the lid seals, vents and filter housings should be checked and, if any of these are found to be damaged or unserviceable the container must not be used. Furthermore, to avoid recontamination, the seal area, filter and/or vent springs should be kept clean and serviceable.
Aluminum containers can be damaged by chemi-cal disinfectants; for this reason, they cannot be immersed in disinfectant solution, a method employed during transport of used instruments which has become obsolete anyway. Where lidded containers fitted with vents or filters are employed, the condition of the lid seals, vents and filter housings should be checked and, if any of these are found to be damaged or unserviceable the container must not be used. Furthermore, to avoid recontamination, the seal area, filter and/or vent springs should be kept clean and serviceable.
2.2 Sterilization procedures
2.2.1 Steam sterilization
Steam sterilization utilizes a saturated atmosphere of pure water vapor heated to a temperature of at least 121 °C reaching all surfaces of the objects being sterilized. Steam sterilization is the safest procedure for both hospitals and general practice. It is therefore to be preferred over all other methods.
For porous goods (e.g. textiles), complete aeration and steam penetration must occur. As prescribed by DIN EN 285, steam sterilization is to be conducted at a temperature of 121 °C for 15 minutes, or at 134 °C for at least 3 minutes: Deviation from these recommendations requires prior validation. Pulsed vacuum procedures are currently used to assure complete evacuation of the sterilization chamber and its contents and to obtain an even distribution of steam throughout the chamber.
The following factors can reduce the effectiveness of steam sterilization:
For porous goods (e.g. textiles), complete aeration and steam penetration must occur. As prescribed by DIN EN 285, steam sterilization is to be conducted at a temperature of 121 °C for 15 minutes, or at 134 °C for at least 3 minutes: Deviation from these recommendations requires prior validation. Pulsed vacuum procedures are currently used to assure complete evacuation of the sterilization chamber and its contents and to obtain an even distribution of steam throughout the chamber.
The following factors can reduce the effectiveness of steam sterilization:
· inadequate steam quality e.g. non-condensable gases, wet steam, over-heated steam;
· inadequate evacuation, air pockets, leaks e.g. from vents, door seals.
Intermittent deficiencies in the apparatus are more easily located through lot-specific rather than periodic controls.
A build-up of condensation can hinder effective sterilization. This can be avoided by conditioning (e. g. preheating) the sterilization goods within the sterilizer. Manufacturers are required to provide the appropriate program settings for the preconditioning procedure. When sterilization goods are appropriately packaged and the sterilizing chamber correctly loaded with a mixed batch of sterilization goods typical of any hospital, the goods must be dry on removal. An above average accumulation of condensation must not be masked by the use of towels.
When goods removed from the sterilization chamber are found to have either wet packaging or to have collected condensation, they must be considered unsterile and cannot therefore be used due to the immediate danger of recontamination.
Mixed cycles of instruments and textiles are re-commended for hospitals, providing consideration is given to DIN EN 554.
When an instrument becomes unsterile during a medical procedure and is needed for immediate reuse, it can be sterilized in packaged form at 134 °C in a non-centralized location. The sterilization of larger units in the operating room or in adjacent “sterilization sub-locations” is, however, to be avoided.
Instruments used on patients who are suspected to have Creutzfeldt-Jacob disease may not be reused and should be treated as single-use (disposable) devices.
However, if reuse of a single-use instrument is unavoidable, a special treatment must be carried out; steam sterilization at a temperature of 134 °C for 60 minutes is recommended. If this is not possible, then, prior to sterilization at 134 °C for the usual duration, disinfection must be performed with 1 molar sodium hydroxide solution or 2.5% to 5% sodium hypochlorite solution for 24 hours.
A build-up of condensation can hinder effective sterilization. This can be avoided by conditioning (e. g. preheating) the sterilization goods within the sterilizer. Manufacturers are required to provide the appropriate program settings for the preconditioning procedure. When sterilization goods are appropriately packaged and the sterilizing chamber correctly loaded with a mixed batch of sterilization goods typical of any hospital, the goods must be dry on removal. An above average accumulation of condensation must not be masked by the use of towels.
When goods removed from the sterilization chamber are found to have either wet packaging or to have collected condensation, they must be considered unsterile and cannot therefore be used due to the immediate danger of recontamination.
Mixed cycles of instruments and textiles are re-commended for hospitals, providing consideration is given to DIN EN 554.
When an instrument becomes unsterile during a medical procedure and is needed for immediate reuse, it can be sterilized in packaged form at 134 °C in a non-centralized location. The sterilization of larger units in the operating room or in adjacent “sterilization sub-locations” is, however, to be avoided.
Instruments used on patients who are suspected to have Creutzfeldt-Jacob disease may not be reused and should be treated as single-use (disposable) devices.
However, if reuse of a single-use instrument is unavoidable, a special treatment must be carried out; steam sterilization at a temperature of 134 °C for 60 minutes is recommended. If this is not possible, then, prior to sterilization at 134 °C for the usual duration, disinfection must be performed with 1 molar sodium hydroxide solution or 2.5% to 5% sodium hypochlorite solution for 24 hours.
2.2.2 Dry heat sterilization
The method of sterilization using dry heat has several deficiencies:
· heat distribution over the entire surface of the object occurs relatively slowly;
· the formation of cold pockets reduces the reliability of the procedure;
· the preparation and the disposition of the sterilization goods greatly influences the effectiveness of the procedure;
· validation of the procedure is not possible.
With a few exceptions not directly involving patient care, even when the chamber is correctly loaded, dry heat sterilization is not a dependable procedure. The use of dry heat sterilization in either hospital or general practice is therefore not acceptable!
Should this procedure be used despite its known deficiencies, then a temperature of 180 °C for at least 30 minutes must be maintained.
Should this procedure be used despite its known deficiencies, then a temperature of 180 °C for at least 30 minutes must be maintained.
2.2.3 Gas sterilization
Gas sterilization utilizes a microbicidal gas at a low temperature in an air tight system and should only be used to disinfect heat sensitive equipment. When purchasing or replacing equipment, it is always preferable to acquire instruments or apparatus that can be sterilized using steam. Moreover, any equipment which is routinely sterilized using gas should be assessed for its suitability to undergo steam sterilization.
All the required conditions for sterilization, i. e. temperature, humidity, gas concentration and duration of exposure must be attained throughout the interior and exterior surfaces of the object to be sterilized.
Whenever gas sterilization is considered as an alternative to steam sterilization, a full appraisal of the relevant risks including toxicological hazards to staff and patients, and benefits such as prolonged use-life of equipment, is required.
The choice of gas sterilization procedures and the classification of goods to be subjected to gas sterilization should be carried out in consultation with the hospital epidemiologist. The regional centralization of gas sterilization is advisable.
All the required conditions for sterilization, i. e. temperature, humidity, gas concentration and duration of exposure must be attained throughout the interior and exterior surfaces of the object to be sterilized.
Whenever gas sterilization is considered as an alternative to steam sterilization, a full appraisal of the relevant risks including toxicological hazards to staff and patients, and benefits such as prolonged use-life of equipment, is required.
The choice of gas sterilization procedures and the classification of goods to be subjected to gas sterilization should be carried out in consultation with the hospital epidemiologist. The regional centralization of gas sterilization is advisable.
2.2.3.1 Gas sterilization using ethylene oxide
Because of its carcinogenic and mutagenic properties, ethylene oxide is considered to be a dangerous gas and as such is subject to regulation. The German TRGS 513 regulations specify in detail the correct installation, operation and supervision of gas sterilizers utilizing ethylene oxide.
Low sterilization temperature and high penetration capacity characterize this form of sterilization. The desorption of ethylene oxide must occur within the sterilization chamber until the ambient concentration has undoubtedly fallen below the required threshold concentration (in German TRK value). Measurements of the so-called “release threshold” must be documented.
Low sterilization temperature and high penetration capacity characterize this form of sterilization. The desorption of ethylene oxide must occur within the sterilization chamber until the ambient concentration has undoubtedly fallen below the required threshold concentration (in German TRK value). Measurements of the so-called “release threshold” must be documented.
2.2.3.2 Gas sterilization using formaldehyde
Although formaldehyde is less toxic than ethylene oxide, it is still a dangerous gas. As with ethylene oxide, in Germany, the use of formaldehyde as a sterilizing agent is subject to legal regulation under TRGS 513. An operating temperature of between 48 °C and 60 °C is required when using formaldehyde as a sterilizing agent. For reasons of safety, the sterilizer should always be operated at the highest temperature tolerated by the sterilization good as stated by the item’s manufacturer. Although the efficacy of formaldehyde and ethylene oxide as sterilizing agents is comparable, under similar operating conditions formaldehyde has a comparatively shorter desorption phase.
2.2.4 Sterilization using plasma
Sterilization using plasma is a non-toxic process carried out at a temperature of 45 °C for a duration of between 45 and 80 minutes depending on the program. Plasma sterilization is suitable for instruments sensitive to heat or moisture. Instruments of this type can be sterilized on a routine basis if they comply with the conditions of the positive list or if their ability to undergo sterilization can be proven within the frame of a product validation. Hollow instruments with long narrow lumens, particularly instruments made of metal, can only be sterilized within the limits stated by the manufacturer.
2.3 Sterilization control and documentation
Quality control procedures with appropriate supporting documentation should be used to ensure that only sterile equipment and materials are used for the treatment of patients. The nature and frequency of quality controls should be directed by the technical guidelines for the efficiency and safety of the respective programs. Quality control and documentation methods for sterilization procedures are detailed in DIN EN 554. Matters covered include:
· the automatic and continual display of the chamber temperature, the chamber pressure, and the time for each sterilized load,
· a system to differentiate between processed (sterilized) and unprocessed objects,
· the allocation of lot numbers to individual loads,
· the release of the lot following confirmation that the validated sterilization cycle was completed within the limits of the specified values,
· monitoring of the most unfavorable (worst case) sterilization conditions with standardized non-biological (physical-chemical) indicators.
The efficacy of sterilization procedures is to be tested according to current standards. The frequency of testing should be guided by the relevant technical information concerning the operational safety of a particular piece of apparatus, the frequency of its use, and appropriate valid standards. For steam sterilizers, repeated performance tests should be carried out using physical measurement where technically possible. Where physical measurement is not possible, and for gas sterilizers, testing should be performed using biological indicators in accordance with the appropriate standards (directive values: every 30 lots but at least every 14 days). Documentation detailing temperature and pressure measurements, lot records and the results of physical or biological testing should be kept for a minimum of 10 years.
Small sterilizers must also be covered by the appropriate measures to safeguard against operating at insufficient pressure levels, low temperatures or curtailed processing times. The standards of sterilization procedures are equally valid for hospitals and in general practice.
Small sterilizers must also be covered by the appropriate measures to safeguard against operating at insufficient pressure levels, low temperatures or curtailed processing times. The standards of sterilization procedures are equally valid for hospitals and in general practice.
2.4 The shelf-life of sterile materials
Because of great variation in both the form of packaging and methods used to store sterile goods, it is not possible to make a recommendation concerning the shelf-life. However, based on logistics, maximum storage periods of between 3 to 6 months have proven feasible. This does not however, apply to sterile goods prepared by industry.
3. Single-Use Products
Within both hospital and general medical practice, medical devices designed for single-use (disposable) articles should be employed only if through the use of these items, the quality of diagnostic and therapeutic measures can be guaranteed or the protection of personnel enhanced.
In Germany, the definition of a medical device as “single-use” is given by the Medical Device Law. This law does not, however, take into account that a part, or parts, of a single-use product can be reprocessed and therefore render the item a multiple-use product. In such a case, the reprocessing procedure must fulfill the following conditions:
In Germany, the definition of a medical device as “single-use” is given by the Medical Device Law. This law does not, however, take into account that a part, or parts, of a single-use product can be reprocessed and therefore render the item a multiple-use product. In such a case, the reprocessing procedure must fulfill the following conditions:
3.1 Reprocessing a single-use product
As with the sterilization of other goods (detailed above), the reprocessing of single-use products must be viewed as a complete procedure from the initial use on the patient, through disinfection, cleaning, performance test, packaging, to sterilization. With respect to reprocessing a single-use product, particular attention must be given to the following points:
· that the patient must not be exposed to a higher risk through the use of a reprocessed article than would be associated with a single-use product,
· that the material of the product remains unchanged and safe,
· that the reprocessing of an item does not constitute a danger to medical staff.
· that the reprocessing of a single-use item fulfills the same requirements as have to be met when it is first produced.
Although the reprocessing of products intended for single use is not prohibited by German law, in terms of liability, the reprocessing of such items requires a high degree of caution. Any reduction in the quality of the medical device that could result in the patient being endangered must be precluded.
If the manufacturer specifies his product as a single-use item which, consequently, is not intended for reuse, it must be assumed that reprocessing of the item bears a health hazard as defined in the German Medical Device Law. This assumption may, however, be refuted by the reprocessor, if appropriate documentation clearly indicates that the relevant guidelines were duly followed (see Attachment to Number 7 of “Guidelines for Hospital Hygiene and Infection Prevention: Hygiene Requirements in the Processing of Medical Devices”). Failure to provide documentation indicating that the guidelines detailed in the German Medical Device Law (§4, Abs. 1, Nr. 1) were followed can result in legal action against the individual responsible for reprocessing.
If the manufacturer specifies his product as a single-use item which, consequently, is not intended for reuse, it must be assumed that reprocessing of the item bears a health hazard as defined in the German Medical Device Law. This assumption may, however, be refuted by the reprocessor, if appropriate documentation clearly indicates that the relevant guidelines were duly followed (see Attachment to Number 7 of “Guidelines for Hospital Hygiene and Infection Prevention: Hygiene Requirements in the Processing of Medical Devices”). Failure to provide documentation indicating that the guidelines detailed in the German Medical Device Law (§4, Abs. 1, Nr. 1) were followed can result in legal action against the individual responsible for reprocessing.
Finally, the economics of reprocessing single-use items should be considered independently of any legal aspects.
Hygiene Requirements within the Framework of Quality Assurance for Ambulatory Surgery
"Ambulatory" or "outpatient" surgery refers to all surgical treatment methods in which the patient spends the nights immediately preceding and following an operation at home in his own bed.
One of the basic principles applying to ambulatory surgery is that the hygienic measures required are the same as those that apply to a similar operation under inpatient conditions; in both cases, different operations can impose different hygienic demands. Furthermore, ambulatory surgery must not entail a greater risk of infection to the patient than inpatient surgery.
The risk of infection can be assessed by referring to the appropriate categories detailed in the RKI (Robert Koch-Institute) Guidelines (appendix to point 4.3.3 of the Guideline for Hospital Hygiene and Infection Prevention).
Next to the necessary structural and technical prerequisites for an ambulatory operation, organizational measures play a decisive role in the prevention of nosocomial infection. This particularly applies to the personal discipline of the surgeons and other medical personnel. For example, persons suffering from infectious diseases or local purulent infections must not be allowed to work in the operating room whilst any risk of transmission of the infection exists.
1. Structural Measures
Definitions:
· A functional element is the smallest unit of space, such as a workplace or a room, which is enclosed by walls.
· A functional unit consists of several functional elements which are physically located together in order to provide a service (e.g. operating room and a room for the induction and subsequent recovery from anesthesia].
· A functional department consists of several functional units and their associated functional elements; i.e. all those rooms needed in the vicinity of the operating room.
In terms of structure, the hygiene standards of the functional rooms must meet the requirements of the operations to be performed. It is recommended that an experienced hospital epidemiologist is consulted during the planning stage of any operation. Depending on the condition of the patient, the type of surgery and the number of medical personnel involved, less exacting requirements may be imposed. Where operations carry a particularly high risk of infection, the implementation of structural measures such as those given in the RKI guidelines is essential. This would apply to operations performed, for instance, on bones, joints, large blood vessels, in large body cavities and the implantation of foreign material.
Operations with differing degrees of contamination risk may only be performed in the same room if any increased risk of infection to the patient is ruled out by the application of appropriate functional and organizational measures. All surfaces, furnishings and equipment must therefore be designed to allow reliable and effective disinfection.
1.1 Room requirements and layout
The functional rooms must be physically separated from the remainder of the clinic including all other examination and treatment rooms.
Depending on the type of surgery performed, the following are needed:
· one or more operating rooms or intervention rooms,
· one or more preparatory rooms,
· a waste disposal room,
· a room for processing and sterilization,
· a transfer area complete with changing rooms for personnel and patients,
· a recovery room.
Where there are several operating rooms, a mirrored duplication of equipment is advisable. In cases where only a single operating room is available, an additional room for minor surgical interventions (equipped with X-ray apparatus and plastering facilities if necessary) has proved advantageous.
Whilst an operating room should not be smaller than 20m2, the upper size limit is dependent on the space requirements of any technical equipment. Washbasins and sinks are not permitted in operating rooms. Hand washing facilities can however be installed in rooms used for minor surgical interventions.
As well as providing an area in which both the induction and subsequent recovery from anesthesia can take place, preparatory rooms can also act as stores for frequently needed drugs and equipment. Furthermore, hand washing facilities may also be installed in preparatory rooms for the purpose of pre-operative hygiene.
The waste disposal room can be used for the sorting and temporary storage of used and recyclable items, the temporary storage of soiled laundry and, if necessary the housing of cleaning utensils.
As stipulated in both the Guidelines of the Robert Koch-Institute and the Regulations of the Professional Associations, under no circumstances should instrument processing or sterilization be carried out in operating rooms: These processes must be under- taken in a separate room exclusively intended for such activities.
If separated "clean" and "contaminated" work rooms are not available, a single room should be furnished in a way that ensures the functional separation of uncontaminated and contaminated work activities.
In principle, so-called "flash-sterilization" must be rejected and only tolerated as an emergency measure to sterilize an instrument that has been "dropped" but is vital for the continuation of the operation.
In order to minimize the introduction of pathogens into the operating section (particularly by personnel, patients and materials), transfer areas are to be used to separate the functional rooms from other examination and treatment rooms. Transfer areas can also be combined with changing rooms for patients.
Whilst toilets can be installed adjacent to the recovery room or transfer areas, they must not be located within the functional rooms.
For reasons of hygiene, it is not necessary to allocate the recovery room to the operating department. However, allocation to the operation department is reasonable if it ensures better postoperative supervision of the patient.
1.2 Ventilation systems
The installation of a ventilation system primarily serves to comply with the requirements of good working conditions. As well as maintaining the required room temperature, ventilation systems also perform a number of other specialized tasks on the ambient air. Amongst others, these tasks include substantially reducing the numbers of microorganisms, dust particles and the concentration of anesthetic gases and odorous substances.
Depending on the operation to be carried out, the type and dimensions of the ventilation system should meet the requirements of the occupational medicine regulations and hospital hygiene guideline values for bioburden. This includes compliance with the requirements of DIN 1946, part 4.
Attention should also be given to the legal provisions for minimizing the ambient air concentrations of narcotic gases.
2. Management and Organizational Measures
In order to prevent the spread of infection from both the personnel and patient to the wound, and also from the patient to personnel, operating room (OR) apparel and draping materials must provide an effective barrier against pathogens. Fluid-impermeable clothing must therefore be worn for operations whenever fluids are expected. Wearing an apron and separate sleeves either under or over a permeable OR gown does not offer adequate protection. The materials covering the patient should be sufficiently rugged to withstand any mechanical stress caused by the surgeon or instruments as well as exposure to fluids or pressure.
The aim of correct processing is to guarantee quality assurance by using appropriately disinfected and sterile supplies. Correct processing serves to protect the patient, avert the risk of infection to medical personnel and preserve the serviceability of the treated goods. Any sterile supplies containing condense or whose packaging is moist when removed from the sterilization chamber, are deemed to be unsterile and must not be used. Any deliberation concerning the reuse of so-called "disposable" items must focus on the quality assurance of the article, its material safety, and the protection of staff during subsequent reprocessing. The patient must not be exposed to any greater risk through the use of a reprocessed article than would be presented during the initial use of an article intended for single-use.
When processing endoscopes, scrupulous adherence to all the protective measures required for the prevention of infection must be advocated. Microorganisms are still frequently detected on endoscopes which are assumed to have been impeccably processed. It must therefore be demanded that all parts of the endoscope are cleaned and disinfected. Based on current knowledge, endoscopes which do not meet these requirements may no longer be used. Endoscopes must be sterile when used for any operations in which skin and/or mucous membranes are perforated and when physiologically sterile cavities are penetrated. Consistent results, including the quantitative reduction of pathogens, can only be achieved with the aid of a closed automatic cleaning and disinfection system preceded by manual cleaning if necessary. Furthermore, a freshly processed endoscope and sterile accessories must be used for each patient.
Reference is made to the management and organization of disinfection procedures in the following recommendations of the working group:
· Infection prevention in arthroscopy and arthroscopic surgery (pp. 32)
· Hygiene measures in endoscopic procedures (pp. 39)
· The processing of instruments and materials in hospitals and general practice (pp. 44)
· OR clothing and patient draping (pp. 50)
According to Section 9 of the Accident Prevention Regulation, an infection control policy must be drawn up for areas designated for the medical examination and treatment of persons as either outpatients or inpatients. An infection control policy should therefore stipulate the exact specifications required for a number of essential activities including cleaning, disinfection, sterilization, supply, and disposal. Moreover, the policy should also specify the duties and responsibilities of the staff designated to implement and supervise these essential activities. Furthermore, it is recommended that additional hygienic standards such as the sluicing procedure for personnel and patients, skin and mucous membrane antisepsis, and the application of venous line or urine drainage are also incorporated into the infection control policy. Shaving should be exclusively restricted to hair which constitutes a hindrance to the operation and/or entails a hygiene risk. Furthermore, shaving must only be performed outside the operating room immediately prior to the operation. The use of disinfectants and antiseptics is to be restricted to those which have either been awarded a test certificate by the German Society for Hygiene and Microbiology (DGHM) or have proven suitable following similar scientific examination.
The recording of infection statistics is emphatically demanded in order to facilitate the targeted prevention of all nosocomial infections, and particularly postoperative infections. Moreover, the registration of infections would serve to both enhance patient care and protect the surgeon against unwarranted claims.
Installations for Ventilation and Air-Conditioning
Ventilation and air-conditioning installations (VACI) in hospitals are primarily designed to create and maintain adequate workplace conditions. The conditioning of air in operation areas also serves to prevent infection by reducing airborne contamination of the operation site. In this way, an essential prerequisite for the prevention of wound infection is fulfilled. This is especially relevant for all primarily aseptic operations, particularly those involving the implantation of alloplastic materials.
In Germany, the DIN standard 1946 subsection 4 (status: December 1989) defines the specifications for VACI in hospitals. In Austria, these are defined by the ÖNORM H 6020 subsection 1 (status: 1st November), and in Switzerland by the “Regulations for Construction, Operation and Maintenance of Ventilation and Air-Conditioning Installations in Hospitals (edition 1987)” of the Swiss Institute for Health and Hospital Service. All regulations for VACI in hospitals are currently being revised; any changes to these regulations should be implemented accordingly. In addition, the following recommendations are made:
In Germany, the DIN standard 1946 subsection 4 (status: December 1989) defines the specifications for VACI in hospitals. In Austria, these are defined by the ÖNORM H 6020 subsection 1 (status: 1st November), and in Switzerland by the “Regulations for Construction, Operation and Maintenance of Ventilation and Air-Conditioning Installations in Hospitals (edition 1987)” of the Swiss Institute for Health and Hospital Service. All regulations for VACI in hospitals are currently being revised; any changes to these regulations should be implemented accordingly. In addition, the following recommendations are made:
1. Low turbulence, large-surface air outlets – the so-called “laminar flow systems” – are superior to other air-conditioning systems and impart a high level of hygienic safety as far as airborne organisms are concerned. Systems of this type should be preferred in both new and renovated buildings.
2. The ceiling panel should be large enough to ensure that all those positions requiring special protection (such as the operation site, OR team and instrument tables) are enveloped in clean air. The size of the ceiling panel required is therefore dependent on the type of operations to be performed. It is urgently recommended to mark the active area of the ceiling panel on the floor, in order to provide a visual aid to OR and anesthesia personnel and for positioning the OR table. Special attention should be paid to the following:
· persons and instruments should not be positioned in the peripheral zone between filtered, laminar air and turbulent room air;
· the boundaries of the filtered air areas; these are recognizable by the temperature difference between fresh air and room air;
· in terms of safe screening, additional expenditure on a sufficiently large ceiling panel with laminar flow can be more than compensated by savings on peripheral installations.
3. In order to meet the requirements stated under item 2 above, a higher total flow volume is required than that given in DIN 1946 subsection 4 which states a minimum fresh air volume flow of 2,400 m3/h. The recommended specification for a 3 m x 3 m ceiling panel is a volume flow of 8,000 m3/h, with a minimum outer air volume flow of 1,200 m3/h. The remainder of the inflowing air can consist of conditioned (i. e. three-stage filtered) circulating air. In this way, energy consumption can be considerably reduced. For large ceiling panels (>3 m x 3 m) with aprons extending as far as the door frame lintels, the velocity of air flowing into the operating room should be approx. 0.25 m/s. At these flow velocities, the disturbance and resuspension of particles from solid surfaces does not occur.
4. The number of persons present should be limited to the minimum necessary. No more than three doors should open directly into the operating room; in all cases doors should be of the automatic sliding variety. Furthermore, viewing windows and intercom telephones will help to reduce the number of times the doors have to be opened and closed.
5. The annual hygiene check required to comply with German Standards (DIN) should be supplemented by daily microbiological screening of specimens taken from the vicinity of the wound. For rooms with low turbulence air-conditioning systems and three-stage filtering (e.g. G4, F7, H13), the following recommended and limiting values are suggested for the area close to the wound (1, 2):
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Particle concentration (particle diameter >0.5 µ/m3 (1/m3))
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|
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Recommended value:
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4,000
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Limiting value:
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10,000
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Concentration of airborne organisms (cfu/m3)
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Recommended value:
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4
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Limiting value:
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10
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These values are recommended for disinfected operation rooms when no surgeries are performed. A leakage test on the final filter is an indispensable quality control procedure following each replacement of the filter.
References
1. Deutsche Gesellschaft für Hygiene und Mikrobiologie: Empfehlungen zur hygienischen Abnahmeprüfung und zu hygienischen Kontrollen nach DIN 1946 Teil 4 Raumlufttechnische Anlagen in Krankenhäusern. Hyg Med 1989; 14: 168–170.
2. DIN 1946-4 Raumluftechnische Anlagen in Krankenhäusern (Entwurf Stand September 1997).
Requirements for Gloves for Infection Prevention in the Health Service
1. Introduction
In healthcare, gloves need to meet numerous requirements. In addition to protection against cleansing agents, disinfection agents and laboratory chemicals, medical gloves are required to avert the risk of infection, in particular by infectious bloodborne diseases such as hepatitis B, hepatitis C, HIV and smear infections. Whilst the patient must be protected against the transfer of pathogens from the staff, the staff must also be protected against transfer from the patient. Accordingly, the use of safe and reliable gloves is fundamental to the prevention of infection for both patients and staff. The user must therefore be aquainted with the performance limitations of the various materials from which medical gloves are made. In contrast to plain protective gloves, gloves intended to provide protection for patients and medical staff are considered to be medical devices.
Moreover, because medical gloves are required to act as an effective barrier against microorganisms and withstand both mechanical and chemical attrition, the highest quality is demanded of both materials and manufacture. Medical gloves can be divided into two categories, those used for examinations (examination gloves) and those intended for use in the operating room (OR gloves).
Moreover, because medical gloves are required to act as an effective barrier against microorganisms and withstand both mechanical and chemical attrition, the highest quality is demanded of both materials and manufacture. Medical gloves can be divided into two categories, those used for examinations (examination gloves) and those intended for use in the operating room (OR gloves).
2. Materials
2.1 Natural latex
More than 90% of all gloves currently used are made of natural latex. Latex provides a safe barrier against germs and high resistance to tearing, it is highly ductile, flexible and resistant to body fluids. Latex is also well-fitting and thus pleasant to wear. Gloves from natural latex can be produced at low cost and are environmentally friendly. Latex gloves are made from a milky colloid consisting of pure rubber (30–40%) suspended in water (approximately 60%) with the remainder being made up of non-rubber compounds (5–8%) consisting of over 250 different proteins and lipids, carbohydrates, minerals, nucleic acids and resins. Some of the latex proteins have been identified by the latest medical research as highly potent allergens. During the production of a latex glove, numerous substances, e. g. dispersing agents, emulsifiers, stabilizers, preservatives, vulcanization agents and accelerators, are added to the material.
As far as the chemical resistance of latex gloves is concerned, latex gloves are compatible with alcoholic, aldehyde-containing, and saline solutions (Ringer’s solution). However, organic solvents, petroleum ether, animal, vegetable and mineral fats as well as oils such as Vaseline and paraffin oil damage the latex membrane and severely reduce its ability to function as an effective barrier to microorganisms. Skin protection products should therefore be thoroughly removed from the skin before putting the gloves on.
The protective function of the latex glove is also impaired when working with certain cytostatic agents and when inserting endoprostheses with polymethylmethacrylate copolymers (PMMA bone cement). Latex gloves must therefore always be changed after contact with bone cement.
The positive properties of latex do, however, dominate, making this an excellent choice of material for both OR and examination gloves. Moreover, with a few exceptions, this material is well tolerated by the skin.
As far as the chemical resistance of latex gloves is concerned, latex gloves are compatible with alcoholic, aldehyde-containing, and saline solutions (Ringer’s solution). However, organic solvents, petroleum ether, animal, vegetable and mineral fats as well as oils such as Vaseline and paraffin oil damage the latex membrane and severely reduce its ability to function as an effective barrier to microorganisms. Skin protection products should therefore be thoroughly removed from the skin before putting the gloves on.
The protective function of the latex glove is also impaired when working with certain cytostatic agents and when inserting endoprostheses with polymethylmethacrylate copolymers (PMMA bone cement). Latex gloves must therefore always be changed after contact with bone cement.
The positive properties of latex do, however, dominate, making this an excellent choice of material for both OR and examination gloves. Moreover, with a few exceptions, this material is well tolerated by the skin.
2.2 Polyvinyl chloride (PVC)
Because of their low ductility and poor tensile strength, vinyl gloves only offer a partially safe germ barrier and as such are less well suited to medical use. Incompatibility of PVC with skin has not yet been evidenced. PVC is more resistant than latex to diluted inorganic acids, aldehydes, hypochlorites, iodic aqueous solutions and xylol. The use of PVC gloves is not to be recommended when working with alcoholic solvents, heptane, pentane, turpentine, or benzene. Moreover, the manufacture and disposal of PVC gloves can be criticized in terms of its impact on the environment.
2.3. Polyethylene copolymers (PE)
PE is used to manufacture examination gloves and is extremely well tolerated by the skin. However, low ductility, low tensile strength and poor fitting compared to latex gloves have limited the use of PE gloves.
Nevertheless, PE gloves offer excellent protection as under-gloves when working with PMMA and cytostatic agents. PE is highly stable in the presence of alcoholic solutions, aldehydes, ketones, hypochlorites, acids, ammonia-containing and saline solutions. PE gloves are not, however, suitable for work with organic solvents (pentane, turpentine, petroleum ether). When burned, PE does not produce substances which are hazardous to the environment.
Nevertheless, PE gloves offer excellent protection as under-gloves when working with PMMA and cytostatic agents. PE is highly stable in the presence of alcoholic solutions, aldehydes, ketones, hypochlorites, acids, ammonia-containing and saline solutions. PE gloves are not, however, suitable for work with organic solvents (pentane, turpentine, petroleum ether). When burned, PE does not produce substances which are hazardous to the environment.
2.4 Synthetic latex (SL)
SL is used in the manufacture of both examination and OR gloves and consists of a whole range of different materials such as acrylonitrile-butadiene rubber (NBR), butyl rubber (isoprene), chloroprene resin (neoprene), and polystyrene ethylene butylene mass polymers.
Compared to latex, SL gloves are both less ductile and less durable. SL is not suitable for work with PMMA and cytostatic agents. However, gloves made from polystyrene ethylene butylene mass polymers can be used for the preparation of cytostatic agents. In general, SL gloves are well suited for work with aqueous saline solutions, aldehydes, oils, fats, acids and caustic solutions.
Whilst skin tolerance is good, the production and subsequent disposal of these materials can be criticized in terms of its impact on the environment.
Compared to latex, SL gloves are both less ductile and less durable. SL is not suitable for work with PMMA and cytostatic agents. However, gloves made from polystyrene ethylene butylene mass polymers can be used for the preparation of cytostatic agents. In general, SL gloves are well suited for work with aqueous saline solutions, aldehydes, oils, fats, acids and caustic solutions.
Whilst skin tolerance is good, the production and subsequent disposal of these materials can be criticized in terms of its impact on the environment.
2.5 Other materials
Various other materials are used to manufacture gloves for specialized purposes. However, these are so rarely used that they will not be described here.
3. Manufacturing Processes
Basically, it is necessary to differentiate between powdered and unpowdered gloves. Where powders are needed in the manufacturing process, only those which can be absorbed are now used. When gloves are manufactured using the dipping process, powder is used primarily as a releasing agent and to prevent the glove adhering to the mold. Powder is therefore also found on the outside surface of so-called “un-powdered” gloves. Furthermore, to prevent the glove sticking to itself and to facilitate the insertion of hands, the inside surfaces of the gloves are either powdered or undergo specialized treatment.
With few exceptions the “chlorination process” is usually used to produce powder-free gloves. Whilst still on the mold, the glove is submerged in a chlorine solution for a few minutes. This results in an alteration to the surface of the material. The chlorine is then neutralized by an ammonia solution before being thoroughly washed to remove the resulting ammonium chloride.
In the Medical Glove Report, 9/1997, the FDA drew attention to the fact that several critical parameters relating to the chlorination process must be heeded: Failure to do so may result in damage to the glove membrane and a concomitant reduction in its ability to provide a safe barrier against germs. In addition to the mechanical and physical disadvantages already mentioned, chlorinated gloves age more rapidly than powdered gloves. Relatively rapid aging has also been observed for coated gloves. Thorough inprocess controls are therefore required to exclude the possibility of either a defective or poor quality product.
With few exceptions the “chlorination process” is usually used to produce powder-free gloves. Whilst still on the mold, the glove is submerged in a chlorine solution for a few minutes. This results in an alteration to the surface of the material. The chlorine is then neutralized by an ammonia solution before being thoroughly washed to remove the resulting ammonium chloride.
In the Medical Glove Report, 9/1997, the FDA drew attention to the fact that several critical parameters relating to the chlorination process must be heeded: Failure to do so may result in damage to the glove membrane and a concomitant reduction in its ability to provide a safe barrier against germs. In addition to the mechanical and physical disadvantages already mentioned, chlorinated gloves age more rapidly than powdered gloves. Relatively rapid aging has also been observed for coated gloves. Thorough inprocess controls are therefore required to exclude the possibility of either a defective or poor quality product.
4. Factors Relating to Allergy
Two types of allergy may occur following contact with latex-based materials (in particular, after wearing a latex glove). The so-called “delayed-type” allergy (Type IV allergy), is generally triggered by additives, particularly accelerators and antioxidants such as thiurame, carbamate and benzothiazole. Since thiurame has been recognized as a trigger for Type IV allergies, glove production using this compound has become rare and the number of allergies is decreasing. Allergies have seldom been observed for PVC and PE gloves.
With the increased use of latex gloves since the mid 1980s, there has been a rise in the incidence of immediate type allergies (Type I allergy), the so-called latex allergy. According to current knowledge, the risk of allergic reaction rises with increased concentration of proteins in the glove. The latex proteins are absorbed via the skin and the respiratory passages. As a result of the manufacturing process, powdered latex gloves contain a relatively high concentration of free proteins which bind to the basically inert cornstarch powder used during the process. Powdered latex gloves therefore harbour a particular risk in terms of their potential to induce an allergic reaction. The cornstarch powder, along with its adsorbed latex proteins is agitated and can become airborne when the gloves are pulled on and off. Once the powder/protein complex is airborne it can enter the respiratory tract and come into contact with the connective tissues and mucous membranes. Extensive skin contact with latex through the continuous wearing of gloves can lead to irritation because of the formation of fluid inside the glove and softening of the skin. The protective barrier that the skin normally provides is impaired facilitating the penetration of allergens. This mechanism of irritation is aggravated by powdered gloves because the powder creates an alkaline environment in the moist layer on the skin which further increases irritation. The combination of powder and allergenic latex proteins is an important factor in the initiation of immediate allergic reactions through direct skin contact and from airborne particles.
The risk of latex allergies amongst patients is growing due to increasing and often unidentified sensitivities. The number of reports of life-threatening anaphylactic reactions during rescue operations or anesthesia is also increasing. Those particularly at risk are atopic individuals and persons having frequent contact with latex and, particularly if symptoms of neurodermatitis, hay fever or asthma are already present or persons with hand exanthema, Spina bifida or especially after multiple surgery. Persons suffering allergic reaction to fruits such as bananas, kiwis, walnuts, apricots or peaches, may also react to latex proteins (cross-sensitivity). For the above noted reasons, clinics are increasingly tending towards the use of materials free from natural latex for products in intensive care units, products used by rescue teams as well as those used for anesthesia and surgical intervention.
For medical gloves, good skin compatibility is of vital importance. Frequent washing and disinfection of the hands, wearing gloves for long periods, the occlusion effect, and occasionally the materials from which gloves are made may cause skin irritation. 50% of all skin problems are cases of skin irritation alone. Adequate and consistent skin care is the most important aspect of skin protection. However, skin care should not be carried out immediately prior to donning gloves because care products containing fats can damage the glove membrane and impair its function as a germ barrier. Thorough skin protection can effectively reduce the likelihood of skin irritations and thus the risk of allergic reaction.
With the increased use of latex gloves since the mid 1980s, there has been a rise in the incidence of immediate type allergies (Type I allergy), the so-called latex allergy. According to current knowledge, the risk of allergic reaction rises with increased concentration of proteins in the glove. The latex proteins are absorbed via the skin and the respiratory passages. As a result of the manufacturing process, powdered latex gloves contain a relatively high concentration of free proteins which bind to the basically inert cornstarch powder used during the process. Powdered latex gloves therefore harbour a particular risk in terms of their potential to induce an allergic reaction. The cornstarch powder, along with its adsorbed latex proteins is agitated and can become airborne when the gloves are pulled on and off. Once the powder/protein complex is airborne it can enter the respiratory tract and come into contact with the connective tissues and mucous membranes. Extensive skin contact with latex through the continuous wearing of gloves can lead to irritation because of the formation of fluid inside the glove and softening of the skin. The protective barrier that the skin normally provides is impaired facilitating the penetration of allergens. This mechanism of irritation is aggravated by powdered gloves because the powder creates an alkaline environment in the moist layer on the skin which further increases irritation. The combination of powder and allergenic latex proteins is an important factor in the initiation of immediate allergic reactions through direct skin contact and from airborne particles.
The risk of latex allergies amongst patients is growing due to increasing and often unidentified sensitivities. The number of reports of life-threatening anaphylactic reactions during rescue operations or anesthesia is also increasing. Those particularly at risk are atopic individuals and persons having frequent contact with latex and, particularly if symptoms of neurodermatitis, hay fever or asthma are already present or persons with hand exanthema, Spina bifida or especially after multiple surgery. Persons suffering allergic reaction to fruits such as bananas, kiwis, walnuts, apricots or peaches, may also react to latex proteins (cross-sensitivity). For the above noted reasons, clinics are increasingly tending towards the use of materials free from natural latex for products in intensive care units, products used by rescue teams as well as those used for anesthesia and surgical intervention.
For medical gloves, good skin compatibility is of vital importance. Frequent washing and disinfection of the hands, wearing gloves for long periods, the occlusion effect, and occasionally the materials from which gloves are made may cause skin irritation. 50% of all skin problems are cases of skin irritation alone. Adequate and consistent skin care is the most important aspect of skin protection. However, skin care should not be carried out immediately prior to donning gloves because care products containing fats can damage the glove membrane and impair its function as a germ barrier. Thorough skin protection can effectively reduce the likelihood of skin irritations and thus the risk of allergic reaction.
5. Safety Regulations
As the body responsible for occupational safety ordinances in Germany, the Federal Ministry for Employment and Social Welfare, has reacted to the above findings by announcing a technical regulation for hazardous and sensitizing substances (TRGS 540) in December 1997. The basis for this technical regulation is the ordinance on hazardous substances. The TRGS reflects the status of safety, medical, hygienic and scientific requirements for the handling of sensitizing substances at work. Subsection 3.1 (substitutes), paragraph 4 of the TRGS stipulates that powdered latex gloves are to be replaced by powder-free, low allergen latex gloves or other suitable gloves. Furthermore, in subsection 4.4 (personal protective gear) paragraph 2 states “... latex gloves must be powder-free and low allergen ...”.
This regulation is based on the ordinance for hazardous substances and clearly forbids the use of powdered natural latex gloves as a part of personal protective gear. The employer may only deviate from this regulation if he can achieve adequate protection by other means. If these requirements are ignored and staff are allowed to continue wearing powdered natural latex gloves, the employer is liable to be held responsible by the Accident Insurance Company in the event of a compensation claim by an insurant who has developed a latex allergy as a result wearing gloves of this type.
The TRGS refer exclusively to protective gloves designed for the protection of the wearer: Medical gloves for the protection of the patient or a third party are not mentioned in these regulations.
This regulation is based on the ordinance for hazardous substances and clearly forbids the use of powdered natural latex gloves as a part of personal protective gear. The employer may only deviate from this regulation if he can achieve adequate protection by other means. If these requirements are ignored and staff are allowed to continue wearing powdered natural latex gloves, the employer is liable to be held responsible by the Accident Insurance Company in the event of a compensation claim by an insurant who has developed a latex allergy as a result wearing gloves of this type.
The TRGS refer exclusively to protective gloves designed for the protection of the wearer: Medical gloves for the protection of the patient or a third party are not mentioned in these regulations.
6. European Standards for Medical Gloves
In order to guarantee adequate protection from infection, all disposable medical gloves must comply with the specifications of the European Standard DIN EN 455. This standard states the so-called “Accepted Quality Level” (AQL) as a reference level for the degree of impermeability. To guarantee adequate protection from infection, the AQL level must be <1.5.
In future the following points concerning biological compatibility will be included in the standard (prEN DIN 455-3):
In future the following points concerning biological compatibility will be included in the standard (prEN DIN 455-3):
· The proportion of water-soluble proteins should be reduced to a minimum. According to present knowledge, a threshold value for sensitivity is not known, consequently no limiting value can be established. The protein content has to be monitored during production by the Modified Lowry Method.
· Talcum may no longer be used as a powder. A demand will not be made for a general ban on powdered gloves since these are considered biologically compatible and the powder itself has no apparent sensitivity potential.
· A list of additives used during the glove manufacturing process must be made available to the user.
· Leading manufacturers of gloves have drastically reduced the proportion of water-soluble proteins in accordance with the standard. Most gloves no longer contain thiurame. Unfortunately, scientifically based studies that permit greater insight and evaluation of the entire range of influencing factors are not yet available. Especially because the studies undertaken so far have been carried out on gloves with high allergenic potential, currently available results do not allow any conclusions to be drawn concerning the general effects and mechanisms involved.
7. Requirements
According to current scientific knowledge and technical capabilities, the following requirements can be applied to gloves intended to prevent infection:
· The gloves must provide a germ-proof barrier and must at least comply with EN/DIN 455-1. In-process controls – in particular those governing the production of chlorinated gloves – must be strictly adhered to.
· The effect of mechanical or chemical influences on the barrier function of the glove must be known.
· Synthetic gloves have a lower resistance to damage by needle puncture or cuts. Because of their higher elasticity, latex gloves are considerably more robust.
· The sterility assurance level according to EN/DIN 556 (at least 10–6) must be fulfilled and the endotoxin content must not exceed 20 EU/glove. For non-sterile gloves, the bioburden should be kept as low as possible.
· When used during surgery, strict disciplined procedures must be employed to remove the powder residue from the outside of the glove under aseptic conditions whilst ensuring that no powder falls onto the operation site or the surgical instruments and materials. Because “un-powdered” gloves are in fact powdered on the outside, it is recommended that procedures for the removal of powder should be carried out in all cases.
· The proportion of water-soluble, allergenic proteins should be as low as possible.
· The gloves should not contain thiurame.
· The user must be made aware of all possible contact allergens.
· High-quality gloves must remain affordable.
· The production and disposal of gloves must be acceptable in terms of environmental impact.
8. Outlook
Controversial discussions on the topic of glove-induced allergies should not be undertaken to the detriment of either users or patients. At present, natural latex gloves offer the greatest safety as an effective germ barrier. Alternative materials have not yet reached the same standard of quality at this mechanical and physical durability.
Current production processes for powder-free latex gloves may cause a reduction in the safety of the germ barrier of the gloves. Moreover, because chemical residues may cause additional skin irritations, it is not possible to evaluate attempts to optimize biological compatibility through alternative production processes (FDA, Medical Glove Report, 9/1997).
Current production processes for powder-free latex gloves may cause a reduction in the safety of the germ barrier of the gloves. Moreover, because chemical residues may cause additional skin irritations, it is not possible to evaluate attempts to optimize biological compatibility through alternative production processes (FDA, Medical Glove Report, 9/1997).