The Decontamination, Storage and Use of Flexible and Rigid Endoscopes

Transcription

1 LTHT Infection Control Policies Policy No 21 The Decontamination, Storage and Use of Flexible and Rigid Endoscopes Scope of Policy This policy applies to: All staff employed at LTHT who have direct responsibility for the decontamination, storage and use of flexible and rigid scopes. Key Points Endoscope decontamination is a process that renders the instrument safe for use on the next patient, it consists of cleaning, followed by sterilisation or disinfection. The reprocessing of endoscopes should be carried out in accordance with advice from the Medical Devices Agency (2002) and the British Society of Gastroenterology (BSG) Guidelines for Decontamination of Equipment for Gastrointestinal Endoscopy (2005) Flexible endoscopes are used predominantly in endoscopy departments. They are heat sensitive (cannot withstand temperatures >60 o C) and therefore are re-processed using low temperature liquid chemical disinfectants/sterilants. Rigid endoscopes are predominantly used in operating theatres and are usually autoclavable. Endoscopes entering sterile body cavities must have undergone a sterilisation process. Overall, the incidence of infection following endoscopy is low (Medical Devices Agency 2002), however transmission of serious infections has been documented often associated with lapses in endoscope decontamination, e.g. hepatitis B, hepatitis C, tuberculosis and Salmonella. There are a variety of endoscopes and auto-washer disinfectors in use, therefore it is important that staff are familiar with the equipment they are responsible for and are trained to reprocess and maintain them. When performing or assisting in endoscopic procedures, or when handling used endoscopic equipment, all staff must adhere to Standard Precautions (Universal Infection Control Precautions) - including wearing personal protective equipment. It is essential that clinicians ask CJD risk questions to all patients about to undergo an endoscope procedure ( please see table 4.1 in the TSE (CJD) Policy - CJD Risk Questions for patients about to undergo elective or 1

2 emergency endoscopic procedures likely to involve contact with tissues of potentially high or medium level infectivity ). Where neuroendoscopes are being used a separate new pool needs to be identified to be used on children born since 1st January 1997 (who are unlikely to have been exposed to BSE in the food chain or CJD through a blood transfusion) and who have not previously undergone high-risk procedures.(waiting DAG approval) Infection Risk The risk of transmission of infection is dependent on a number of factors (Medical Devices Agency 2002): - The type of endoscopic procedure The micro-organisms present in any previous patient s secretions The effectiveness of the endoscope re-processing cycle Environmental re-contamination during or immediately after processing The susceptibility of the patient to infection. Re-processing of Rigid Endoscopes Saturated steam under pressure, at the highest temperature compatible with the product, is the preferred method of sterilisation for medical devices (Medical Devices Agency 1997). Modern rigid endoscopes are usually heat tolerant and are therefore autoclavable. Benchtop steam sterilisers e.g. Little Sisters are not suitable for the sterilisation of instruments with lumens (Medical Devices Agency 1997). Without exception heat tolerant endoscopes (and associated accessories) must be sent to the Sterile Services Department for sterilisation by autoclave. Some older rigid endoscopes are heat sensitive and therefore cannot be autoclaved. Wherever possible when these endoscopes are due to be replaced users should purchase heat tolerant endoscopes and send them to Sterile Services Department for autoclaving. Heat sensitive rigid endoscopes therefore require re-processing in liquid chemical disinfectant/sterilant. Users should manually clean rigid endoscopes in accordance with the manufacturer s instructions and guidance from the Medical Devices Agency (2002). When re-processing heat sensitive rigid endoscopes in liquid chemical sterilants, users should follow the guidance below under Sterilisation and disinfection. 2

3 The Reprocessing of Flexible Endoscopes Flexible endoscopes are heat labile (i.e. cannot be autoclaved) and are therefore reprocessed using liquid chemical disinfectants. A properly operating endoscope auto washer disinfector provides a more consistent and reliable method of disinfection than manual re-processing alone (HICPAC 2001). However auto-washer disinfector machines can themselves be a source of infectious agents (MDA 2002). Wherever possible flexible endoscopes must be re-processed in an auto-washer disinfector, any exceptions to this must be discussed with infection control first and the Decontamination Lead for LTHT needs to be made aware of any recommendations. Where exceptions are agreed and manual reprocessing of endoscopes takes place in a trough of chemical sterilant/disinfectant, this should not be used to reprocess other instruments that could otherwise be sent to Sterile Services for steam autoclaving. This practice must be registered with the Decontamination Lead for LTHT. Containers of disinfectant should be kept covered with close fitting lids, with effective local exhaust ventilation i.e. ventilation cupboard. Two stages in the decontamination of endoscopes include; Manual Cleaning - 1st stage The re-processing cycle starts with a thorough manual clean of the endoscope immediately after use, this removes 99% of bio-burden and its importance cannot be over emphasised. Failure to remove deposits of blood, faeces, tissue, mucus, infectious agents and biofilm may result in infection (MDA 2002). Manual cleaning is of particular importance before re-processing endoscopes in liquid chemical disinfectants as some are tissue fixatives, that is they cause proteinacious matter to harden and adhere to the endoscope. Before manual cleaning the outside of the endoscope should be visually checked for damage and a leak test performed. The following points must also be observed: - 1. Thoroughly manually clean used endoscopes with (neutral or preferably)enzymatic) detergent and warm water immediately after use in accordance with the endoscope manufacturer s instructions. All detachable parts should be removed e.g. hoods and suction valves, and cleaned with detergent. 2. Rubber valves covering the work channel must be disposed of after all procedures involving the passage of biopsy forceps, guidewires and/or accessories through the endoscope. 3. Use enzymatic detergent weekly if not already routinely used after each endoscopy. 4. When manually cleaning an endoscope use (only those) single use brushes recommended by the endoscope manufacturer. Use of inappropriate brushes may lead to long narrow lumens being inadequately cleaned. 3

4 5. During the cleaning process pay particular attention to internal channels, crevices and ports to ensure all internal surfaces are cleaned. 6 Dispose of cleaning brushes after cleaning each endoscope. 7. After thorough manual cleaning rinse the endoscope, including all internal channels with fresh tap water Sterilisation/disinfection- 2nd stage There are currently a variety of different endoscope washer disinfectors and chemical sterilants/disinfectants in use across the Trust. It is beyond the remit of this policy to give detailed accounts of the exact use of each product and machine, however the following points should be noted: - 1. Cidex (a type of glutaraldehyde) is no longer used in the Trust. However other types of glutaraldehydes/alderhydes are still being manufactured although they are not the first choice of disinfectant. Glutaraldehydes must not be used without prior consultation with infection control and a COSHH officer. 2. Ensure that the liquid chemical sterilant/disinfectant is compatible with both the endoscope and the autowasher-disinfector machine (MDA 2001). (MHRA 2002(05) 3. The endoscope should be immersed for the required length of time per manufactures instructions, e.g. Perasafe 10 minutes. 4. Sterilise or disinfect endoscopes at the beginning of a list, between patients and at the end of a list. 5. Re-process endoscopes using the just in time principle. That is they should be re-processed immediately prior to use on a patient and not left for long periods before use as this increases the risk of contamination, or overgrowth of micro-organisms. Olympus/Keymed endoscopes need to be reprocessed after 3hrs. as per manufactures instructions 6. Ensure that the endoscope auto washer disinfector is capable and validated to re-process the endoscope in question. 7. Place the endoscope in the washer-disinfector machine in strict accordance with the machine manufacturer s instructions. Staff must be sure that the endoscope is completely immersed and that the correct connectors are used to allow contact of the liquid disinfectant with all internal and external surfaces. Connectors and adaptors must not be altered or customised in any way. 8. All endoscopes entering a sterile body cavity should have undergone a sterilisation process. 4

5 9. Rinse the endoscope in bacteria free water to remove potentially harmful chemical disinfectants prior to use on a patient. N.B. Some endoscope auto washer disinfector machines will do this as part of usual disinfection cycle. 10. After rinsing with bacteria free water dry the internal channels with compressed air/suction as per manufacturer s instructions. N.B. Some endoscope auto washer disinfector machines will do this as part of the usual cycle. 11. Use only sterile water to fill the water bottle and sterilise (or disinfect) the water bottle daily. 12. At the end of each day, prior to storage irrigate internal channels with 70% alcohol and force air dry (Alvarado 2000, MDA 2002). 13. When not in use store endoscopes hanging vertically with all caps and hoods removed to aid drying, away from dirty endoscopes to prevent cross contamination (MDA 2002). The Reprocessing of Endoscopic Accessories 3 Stages - Decontaminating Accessories; Manual cleaning - 1 st stage Ultrasonic cleaning -2 nd stage Sterilization/Disinfection -3rd stage In order to reduce the risk of transmission of CJD through endoscopic procedures joint recommendations from the CJD committee and BSG include; (a) To use single use cleaning brushes for the decontamination of every endoscope. (b) If a biopsy is taken, the valve on the biopsy /channel should be disposed of as clinical waste after each patient. (c) To use only single use biopsy forceps when taking biopsies. (d) Single use equipment is now advised wherever possible. Reusable accessories should only be used in situations where no single use equivalent accessory exists (e.g. oesophageal bougies) and these should be tracked with each patients use. Endoscopic accessories (These) include biopsy forceps, snares and graspers etc. Many of them pierce mucosa and therefore must be sterile on presentation. Endoscopic accessories are designated either single use or reusable; Where accessories are reusable they must be sterilised between uses. If heat tolerant, autoclaving is the preferred method of sterilisation. Wherever possible the accessories should be sent to the Sterile Services Department and returned sterile and wrapped (MDA 2002). Please note that single use endoscopic accessories must NOT to be re-processed (see LTHT Infection Control Policies Decontamination of Hospital Equipment Including 5

6 Medical Devices ). Because of damage caused to delicate endoscopic accessories by the tunnel washers in CSSD some endoscopy departments will perform the initial cleaning of used instruments themselves, if so the following points are to be observed: 1. Preferably use single use accessories. If this is impossible the accessories must be reprocessed using suitable equipment in a controlled environment by properly trained personnel. At all times when handling used instruments that have been exposed to blood and body fluids staff must adhere to LTHT Standard Precautions (Universal Infection Control Precautions). 2. All instruments placed in the ultrasonic cleaner must have undergone prior manual cleaning with neutral/enzymatic detergent and warm water. 3. The positioning of instruments in the bath does not appear to have any effect on the ultrasonic cleaning process. Providing all the items are fully immersed they can be loaded without the use of trays etc. However instruments with jaws should be immersed with the jaws open. 4. There is no recommendation from either the manufacturers or in relevant literature on how frequently the water/cleaning fluid should be changed. In order to prevent the overgrowth of bacteria it is recommended that the water be changed at least once during the day or preferably more frequently, ie after each endoscopy session/list. 5. At the end of each working day the bath should be emptied, wiped with 70% alcohol and left to dry. N.B. when cleaning electrical equipment with flammable liquids ensure the machine is switched off and unplugged first. 6. Any lumened items should be flushed with water after being removed from the ultrasonic cleaner. This is to remove the detergent/water that will have small particles suspended in it. These may bake onto the instrument during the autoclave process and will reduce the working life of fine instrumentation. 7. There is a risk that whilst the ultrasonic bath is in use the liquid inside can become aerosolised and this may contain potentially harmful micro-organisms. It is therefore recommended that the lid be kept closed when the machine is in operation. 6

7 The Purchase, Use and Maintenance of Endoscope Auto-Washer Disinfectors There are a wide variety of endoscope washer disinfectors on the market, some are of better quality than others, and not all are fully compliant with the latest technical specifications (HTM 2030, 1997). Any department wishing to purchase new washer disinfectors should therefore read Annexe A of this policy Microbiological specification for endoscope washers and also contact infection control at an early stage in the tendering process for expert advice. NB. HTM 2030 is due to be replaced in the near future As previously stated there are a number of different auto washer disinfectors in use across the Trust. It is therefore essential that staff are fully trained to use a particular machine, are familiar with its use and potential limitations. Auto washer disinfectors are prone to the formation of biofilm and microbiological contamination, which in turn can result in re-contamination of an endoscope. Poor compliance with manufacturer's instructions and lack of knowledge have led to documented episodes of transmission of infection via endoscopes. Regardless of which type of machine is used the following principles should be followed :- 1. Only those staff who are suitably trained in the use of a particular machine may use it to re-process endoscopes. 2. A record of all training, including initial and refresher training is kept. 3. Ensure service contracts exist, that regular maintenance is performed and keep records of these. 4. Clean and disinfect the machines daily in accordance with the manufacturer's instructions. Disinfect any filtration system in accordance with the manufacturer s advice. Microbiological validation of the efficacy of these two steps by microbiological monitoring of final rinse water quality is necessary where possible e.g the final rinse water from Steris 1 machines cannot be accessed for testing and therefore they do not comply with Samples of final rinse water must be taken (where this is possible) from the machine for microbiological testing and trend monitoring as advised by infection control. 6. Change water filters at specified intervals and keep records of this. 7. Only re-process those endoscopes that are known to be compatible with both the auto washer-disinfector machine and the chemical disinfectant/sterilant in use. 8. Auto washer disinfector machines should not be used to re-process items that could otherwise be sent to the Sterile Services Department for autoclaving. 7

8 9. Use chemical indicator test strips in accordance with the manufacturer s instructions. Identification and Tracing of Endoscopes Contaminated endoscopes have been associated with outbreaks of infection, e.g. multi-resistant pseudomonas pneumonia after bronchoscopy (MMWR 1999). Therefore as part of any subsequent outbreak control measures, tracing of endoscopes may need to take place Each endoscope therefore requires a unique identifier (e.g. the endoscope serial number); this should be recorded in a log when used on each patient. Following recent MDA guidance (MDA 2002) on the traceability of endoscopy accessories and cleaning brushes LTHT are reviewing the actions required to achieve compliance. However where possible single use devices should be used providing they do not compromise clinical outcome Endoscopy Personnel All Trust staff who have responsibility for the decontamination and use of flexible and/or rigid endoscopes must have undergone adequate training in cleaning, handling and disinfecting endoscopes. Records of training should also be maintained (Ayliffe et al 2000).They must also be aware of the workings and potential limitations of the endoscopy washer disinfectors. Training should include close observation until competency has been established (Alvarado et al 2000). Endoscopy personnel should also have undergone training in the hazards associated with using toxic chemical disinfectants and be able to protect themselves and others from their harmful effects, as specified by Control of Substances Hazardous to Health Regulations (Health and Safety Executive 1999). When performing or assisting in an endoscopy, or when handling used instruments all staff should use universal infection control precautions and wear suitable protective clothing. Also see LTHT Infection Control Policies Standard Precautions (Universal Infection Control Precautions). Special Note on High Risk CJD / vcjd patients Please refer to the Infection Control TSE (CJD) policy There is currently no evidence to suggest that CJD / vcjd has been transmitted from one patient to another via an endoscopic procedure. Creutzfeld Jakob Disease and particularly variant CJD is emerging as a potentially significant risk to mankind. Prions, associated with vcjd are extremely resistant to standard decontamination procedures, including 8

9 sterilisation. This presents as a potential problem for the decontamination of endoscopic equipment. It is essential that clinicians ask CJD risk questions to all patients about to undergo an endoscope procedure. Please see table 4.1 in the TSE (CJD) Policy - CJD Risk Questions for patients about to undergo elective or emergency endoscopic procedures likely to involve contact with tissues of potentially high or medium level infectivity ). Prion protein has been found in lymphoid tissue amongst other areas, of the body. Please refer to Appendix 1 in the TSE (CJD) Policy which shows the Distribution of Tissue Infectivity..During endoscopy, biopsies are routinely taken from lymphoid tissue, making the biopsy forcep and the endoscope potential vectors for disease transmission. Please refer to Appendix 4 in the TSE (CJD) Policy which shows the common flexible endoscopic procedures classified as invasive or noninvasive. If a patient is identified at being a high risk of having vcjd please refer to DoH and BSG guideline on invasive endoscopic procedures in patients at risk of harbouring vcjd Appendix 3 in the TSE (CJD) Policy (Prions (infectious proteins) are the probable cause of variant Creutzfeld- Jakob disease (vcjd) and are resistant to normal disinfection/sterilisation processes.) Variant CJD is sometimes difficult to diagnose and the incubation period is unknown. If an endoscope is used on a patient with known or suspected vcjd, then that endoscope will need to be quarantined or possibly even destroyed. This may also be the case if a patient who has undergone endoscopy is then subsequently found (possibly years later) to be suffering from vcjd. If the individual endoscope cannot be identified then all the instruments in that department may need to be destroyed (HSC 1999/178) at great cost. Please also see LTHT infection control policies Transmissible Spongiform Encephalopathies (TSEs). If a patient with known vcjd is to undergo endoscopy dedicated endoscopes are available from the National CJD Surveillance Unit, (tel ) Where neuroendoscopes are being used a separate new pool needs to be identified to be used on children born since 1st January 1997 (who are unlikely to have been exposed to BSE in the food chain or CJD through a blood transfusion) and how have not previously undergone high-risk procedures. ( Patient safety and reduction of risk of transmission of \\cjd via international procedures - EPIC Nov 2006) Awaiting DAG approval References and Further Reading Advisory Committee on Dangerous Pathogens, Spongiform Encephalopathy Advisory Committee (1998), Transmissible Spongiform Encephalopathy Agents: Safe Working and the Prevention of Infection, The Stationery Office (also 9

10 available on line at ).TSE2000 Annex F - Decontamination of Endoscopes - revised November 2005 Annex J - Assessment to be carried out before surgery and endoscopy to identify patients with, or at risk of, CJD - published July 2006 Alvarado CJ, Reichelderfer M. (2000) APIC Guideline for infection prevention and control in flexible endoscopy. American Journal of Infection Control 2000; 28; Ayliffe G (2000) Decontamination of minimally invasive surgical endoscopes and accessories. Report for the Minimal Access Therapy Decontamination Working Group, Journal of Hospital Infection (2000) 45; BSG Working Party Report 2003(Updated 2005) The Report of a Working Party of the British Society of Gastroenterology Endoscopy Committee Health and Safety Executive (1999) Control of Substances Hazardous to Health Regulations SI1999/437 Stationary Office. Health Service Circular (1999) Variant Creutzfeld-Jakob Disease (vcjd): Minimising the Risk of Transmission. 1999/178 NHS Executive. Health Service Circular (1998) Glutaraldehyde. HSC 1998/208 NHS Executive. HICPAC (2001) Draft guideline for environmental infection control in healthcare facilities, Healthcare Infection Control Practices Advisory Committee (HICPAC) Centres for Disease Control and Prevention, Atlanta, USA. HTM 2030 (1997) Health Technical Memorandum 2030 Washer disinfectors, NHS Estates October MHRA Device Bulletin DB2002 (05) Decontamination of Endoscopes Medical Devices Agency (2002) Decontamination of Endoscopes. MDA DB2002(05) July Medical Devices Agency (1997) The Purchase, Operation and Maintenance of Benchtop Steam Sterilisers. MDA DB 9605 Jan Medical Devices Agency (2001) Compatibility of Medical Devices and Reprocessing Equipment with Decontamination Agents. MDA Safety Notice 2001 (28). Morbidity and Mortality Weekly Report (1999) Centers for Disease Control, 48 (26); th July

11 National Institute for Health and Clinical Excellence (Nov 2006) Patient safety and reduction of risk of transmission of Creutzfeldt-Jakob disease (CJD) via interventional procedures.. Consultation Decontamination Manager and Decontamination Engineer Medical and Nursing Personnel - Endoscopy Units Infection Control Steering Group Documentation Control Policy title Policy number 21 Version number 2 Supersedes The Decontamination, Storage and Use of Flexible and Rigid Endoscopes 2003 The Decontamination, storage and Use of Flexible and Rigid Endoscopes Date approved April 2003 Approving body ICC Review date June 2007 Supporting procedure(s) None Lead Director Director of Infection Prevention and Control Previous Author(s) David Green, Senior Nurse Infection Control Current Author(s) Judy Hall, Senior Nurse Infection Control Nurse Contact for further details Judy Hall, Senior Nurse Infection Control Nurse Distribution Matrons, Chief Nurses Group, Consultants, Clinical Directors, Medical Directors (also ed trust wide) Policy Date: April 2003 Revised : June 2007 Review Date: June

12 Appendix A Microbiological specification for endoscope washers 1. Water supply should be of potable quality; soft water is preferred HTM The machine installation must comply with Water Regulations. 3. Water entering the machine should be filtered to remove particulate matter and bacteria (final bacterial filter to 0.2 microns). Bacteria-free rinse water should be provided. Carbon filters must not be used for water filtration. 4. Because of the contamination risk associated with water filtration, these filters must be included in the machine decontamination cycle. 5. Filters must be of the type specified by the manufacturer, and must be changed at frequencies recommended by the manufacturer and agreed with Infection Control. 6. No pipework should allow the accumulation of static water. 7. The manufacturer must specify which detergent/s is/are compatible with their machine and endoscope cleanliness and safety. 8. The machine should be compatible with different disinfectants. The manufacturer should also give guidance as to the number of cycles for which a disinfectant should be used, and advise if and when disinfectant test strips should be used. 9. The machine should clean, disinfect and rinse all internal channels and external surfaces of the range of endoscopes used, in accordance with the local hospital Infection Control Committee protocols and national guidelines. 10. The machine should be programmable to accommodate the disinfectant contact times recommended by the disinfectant manufacturers, the Department of Health and the professional societies such as the British Society for Gastroenterology, and the Infection Control Committee. They should also have a cycle time compatible with the workload of the unit. 11. There must be a cycle counter and fault indicator. 12. There must be a printout of the cycle parameters which can be retained for quality assurance records. 13. There must be a reliable, effective and simple machine disinfection cycle. Cidex (a type of glutaraldehyde) is no longer used in the Trust. However other types of glutaraldehydes/aldehydes are still being manufactured although they are not the first choice of disinfectant. 12

13 14. Glutaraldehydes/aldehydes must not be used without prior consolation with infection control and a COSHH officer. If glutaraldehyde is used for disinfecting scopes, the machine must be capable of disinfection with an alternative disinfectant which will kill environmental mycobacteria. The machine should preferably be capable of being disinfected using 10,000 parts per million hypochlorite solution. 15. There must be an air drying facility to expel fluids and dry the endoscope at the end of a cycle. 16. There must be a facility to irrigate the channels of the scope with alcohol before storage. 17. There must be a leak test facility. 18. Regular maintenance is required to ensure that tanks, pipework, strainers, filters and other machine components are free from deposits, biofilm and limescale. 19. The manufacturer must provide training for personnel on the use, disinfection and microbiological testing of the machine. 20. Microbiological sampling points must be easily accessed. 21. Gluteraldehydes are not the first choice of disinfectant. However if used, the endoscope washer disinfector should minimise the vapour released when the machine is in use, when the disinfectant is in the storage tank and when disinfectant is being added or removed from the machine. 22. The facility in which glutaraldehyde (if used) must be sufficiently adequately ventilated to ensure that the airborne concentration of glutaraldehyde vapour is kept as far below the Maximum Exposure Limit (0.05 parts per million) as reasonably practicable (HSC 1998/208). Guidance on selection and use of local exhaust ventilation can be found in the Trust s Health and Safety Manual. 13