后处理医学和外科手术器械外文文献

Major article Current issues result in a paradigm shift in reprocessing medical and surgical instruments Michelle J Alfa PhD St Boniface Research Centre Winnipeg Manitoba Canada andDepartment of Medical Microbiology University of Manitoba Winnipeg Manitoba Canada Key Words Cleaning Endoscopes Ultrasound Probes The objective of this report is to review the available scientifi c data on reprocessing of medical and sur gical instruments and discuss the current issues related to cleaning and disinfection of fl exible endoscopes and intracavitary ultrasound probes 2016 Association for Professionals in Infection Control and Epidemiology Inc Published by Elsevier Inc All rights reserved In North America medical device reprocessing includes instruc tions for cleaning as well as disinfection or sterilization 1 7Figure 1 shows an overview of reprocessing of medical devices Historically in North America the regulatory focus had been on ensuring that manufacturersvalidatedthedisinfectionandsterilizationprocessand there were no validation requirements for the cleaning component This approach has been shown to be inadequate There have been infectious outbreaks associated with improper cleaning of complex surgical3and endoscope devices 8 17This has prompted changes and the most recent Food and Drug Administration FDA guidance to manufacturers document issued March 15 2015 7now requires val idation of the manufacturer s instructions for cleaning This new requirementisaimedatensuringthatif healthcarepersonnelfollow the cleaning instructions in the manufacturer s instructions for use MIFU the device will be adequately cleaned and therefore achieve high level disinfection HLD or be considered sterilized As reviewed in various medical device reprocessing guidelines 2 6 there are many factors that must be addressed to ensure a quality systems approach including but not limited to staff training and ongoing competency facilities available for reprocessing ade quate reprocessing tools eg leak testing facilities brushes for cleaning channels adaptors for automated endoscope reprocessors and forced air for drying of channels documentation of reprocess ing to ensure traceability and appropriate storage cabinets This report focuses primarily on the cleaning aspect of medical device reprocessing Cleaning of medical devices is aimed at removing patient organic material including blood bone mucus secretions urine and feces In addition cleaning reduces the microbial levels on the device to ensure that the subsequent HLD or sterilization method will be capable of adequately killing any residual microbes To assess clean ing of medical devices there are cutoffs for organic markers that have been established 18 26These organic marker cutoffs are applicable to manufacturer validation testing as well as rapid cleaning moni tors As outlined in the FDA guidance document7there should be at least 2 of these organic markers eg protein and hemoglobin used when performing cleaning validation studies One question that arises is whether the cutoff for adequate cleaning is different for medical devices that are disinfected by HLD versus those that are sterilized Table 1 summarizes some of the published data on what protein and hemoglobin residuals remain after automated clean ing of surgical instruments compared with those left after manual or automated cleaning of fl exible gastrointestinal endoscopes The published data demonstrate that regardless of whether the medical device is to ultimately get HLD eg fl exible gastrointesti nal endoscopes or steam sterilization surgical instruments it is possible to achieve the same level of cleaning Indeed the postautomated cleaning protein cutoff of 4 g cm2for surgical in struments recommended by Lipscomb et al26is similar to the 6 4 g cm2recommended by Alfa et al19 for fl exible endoscopes These studies indicate that cleaning should be able to achieve the same end point for removal of patient derived organic material regard less of whether the terminal treatment for the medical device is HLD or sterilization However for microbial residuals there are no es tablished benchmarks in the FDA guidance document 7Data in the Michelle J Alfa PhD St Boniface Research Centre 351 Tache Ave Winnipeg MB R2H 2A6 Canada E mail address malfa sbrc ca Publication of this article was supported by an educational grant from Clorox Healthcare Sealed Air and Tru D Content of this article was initiated and written by the author with no input or fi nancial support to the author from Clorox Health care Sealed Air or Tru D Confl icts of Interest MA has been an invited guest speaker at many national and international conferences that were sponsored by various companies including Olympus America Inc 3M Inc STERIS Corporation Johnson and Johnson Inc HealthMark Industries Inc and Virox Inc In addition she has provided consulting services for Olympus America Inc KARL STORZ 3M Inc STERIS Corporation and Johnson and Johnson Inc 0196 6553 2016 Association for Professionals in Infection Control and Epidemiology Inc Published by Elsevier Inc All rights reserved http dx doi org 10 1016 j ajic 2016 01 020 American Journal of Infection Control 44 2016 e41 e45 Contents lists available at ScienceDirect American Journal of Infection Control journal homepage www ajicjournal org American Journal of Infection Control published literature establish that the worst case levels of mi crobes before and after cleaning are very different for surgical instruments compared with fl exible endoscopes After patient pro cedures 70 of surgical instruments have 5 102CFU device and after cleaning 85 of surgical instruments have 5 102CFU device 27 The authors found that the microbial level before and after clean ing does not change but the type of microbes changes from skin derived microbes to environment and water derived microbes Whereas for fl exible colonoscopes the precleaning level of mi crobes ranges from 104 109 5CFU channel and the postcleaning worst case level of microorganisms ranges from 103 104CFU channel 19It is clear that the level of microbes on surgical instruments that are steam sterilized is far lower than that on fl exible gastrointestinal endoscopes that get HLD treatment For medical devices that only receive HLD it is critical that the levels of organic and microbial re siduals are reduced as much as possible because there is a lower margin of safety ie lower capacity to kill high levels of bacteria using HLD compared with using sterilization methods It would be useful if the FDA guidance to manufacturers contained recommen dations for microbial cutoffs for the cleaning process and not just for the HLD and sterilization processes Based on the data pub lished to date for fl exible endoscopes there should be 4 log10CFU cm2remaining in channels or on the exterior surface after manual cleaning19 22 27 2 log10CFU cm2after automated endoscope cleaning23 and that for surgical medical devices there should be 4 log10CFU device after manual or automated cleaning 27 30 Data from recent infectious outbreaks8 9 17 24and from research studies31 33have documented that microbes can survive both HLD and sterilization if there are high levels of organic residuals eg biofi lm that can protect them Automation of the cleaning process has been shown to improve removal of organic and microbial residuals20 21and also improves compliance because there are fewer human factors that contribute to errors in completion of the entire process 34In addition to human factors and automation the role of water quality in both automated and manual cleaning is an impor tant consideration because mineral content above 50 ppm can lead to spotting on instruments and higher mineral content can make detergents less effective In addition monitoring of the fi nal rinse water for washer disinfectors using deionized water and for auto mated endoscope reprocessors that use fi ltration or other microbe removal methods it is critical to ensure the microbe levels are within acceptable limits The recommendations in the Advancement of Medical Instrumentation TIR34 should be followed to ensure the water quality is appropriate for the medical devices being reprocessed 35This includes testing the water quality used at the reprocessing site to ensure compatibility with the detergents se lected for routine manual and automated cleaning of medical devices 35 How can health care staff ensure the cleaning of medical devices is being done adequately The discussion to this point has focused on the importance of cleaning of medical devices to reduce the risk of microbes surviving the reprocessing protocol However it is im portant to recognize that the MIFU for reprocessing the medical device is a single component and that the aspects related to the facility eg equipment and water treatment and the staff eg Fig 1 Overview of medical device reprocessing Table 1 Worst case residuals on patient used instruments before and after cleaning Protein g cm2Hemoglobin g cm2 Before cleaning After cleaning Before cleaning After cleaning Surgical instruments n 5 Automated cleaning 373 783 16110 960 43 Flexible endoscopes n 10 No bedside fl ush and manual cleaning 115 516 3685 492 19 Colonoscopes n 10 Bedside fl ush and pump assisted manual cleaning 0 900 20NDND Colonoscopes n 15 Bedside fl ush and automated cleaning ND0 12ND LD NOTE Data presented in this table are extracted from references 19 22 e42M J Alfa American Journal of Infection Control 44 2016 e41 e45 training and ongoing competency are also critical components to ensure adequate reprocessing of medical devices The current North American guidelines4 6and FDA recommendations 36as well as other national guidelines 37 38recommend that a quality system ap proach is needed to ensure that all components are properly followed and monitored One component of the quality system approach is appropriate monitoring the adequacy of cleaning for automated washers for surgical instruments as well as monitoring manual clean ing of fl exible endoscopes The current American National Standard Institute Advancement of Medical Instrumentation ST79 guideline6 recommends weekly preferably daily monitoring of mechanical washer cleaning effi cacy There are a wide variety of cleaning moni tors commercially available for health care washers but there are few published reports comparing these monitoring methods 39It is unclear for many of the commercially available washer cleaning monitors under what conditions they will show failure eg if de tergent is absent if mechanical action is poor or if temperature is incorrect More research is needed to compare various washer clean ing monitors to determine if they are sensitive enough to detect when conditions needed for adequate cleaning have not been met Although culture surveillance post HLD has been used for years in Europe and Australia to monitor fl exible endoscopes 37 38the results take 24 to 48 hours and if contamination is detected the endo scope could already have been used on multiple patients if not quarantined until culture results are available A study by Saviuc et al40documented that microbiologic culture methods post HLD showed there was frequent contamination of endoscopes and that this was primarily associated with routine surveillance and not with endoscopes with identifi able problems that were sent for repair Al though culture surveillance post HLD is useful it does not address the issue of improperly cleaned endoscopes If improper cleaning is not detected and corrected there will be gradual build up of ma terial and microbes that ultimately will result in HLD failure Ideally cleaning monitoring of fl exible endoscopes should be rapid so that improperly cleaned endoscopes can be re cleaned before HLD or sterilization For fl exible endoscope cleaning monitoring there are 2 general methods available that provide rapid results that include detection of ATP or detection of organic residuals eg protein or he moglobin For organic cleaning monitors for endoscopes the expectation is that if the level of protein carbohydrate or hemo globin exceeds the established benchmarks of 6 4 g cm2 1 8 g cm2 and 2 2 g cm2 respectively that the monitor will fl ag positive thereby ensuring the endoscope is re cleaned 5 25For ATP testing the single test kit with published validated data has a cutoff of 200 RLU23 the cutoff varies depending on the kit manufacturer Only a few of these commercially available rapid cleaning monitoring test methods have been validated for endoscope cleaning 22 23 25There are a number of studies that have used these rapid cleaning moni tors to identify inadequate manual cleaning26 41and have shown the value of these methods for monitoring manual cleaning of patient used fl exible endoscopes The expectation is that if the rapid cleaning test shows residuals are above the validated cutoff then the endo scope should be re cleaned and re tested until it meets the acceptable clean benchmark The signifi cance of ATP residuals de tected after HLD41is unknown because this test has only been validated for monitoring manual cleaning of endoscopes Ideally rapid cleaning monitors would ensure that improperly cleaned medical devices get re cleaned before they proceed to HLD orsterilization Ifmedicaldeviceswithunacceptablelevelsoforganic material are subjected to HLD or sterilization the organic material gets fi xed onto the medical device making the material diffi cult to subsequently remove and leading to biofi lm formation In view of the recent infection outbreaks associated with endoscopic retro grade cholangiopancreatography ERCP scopes it is the author s opinion that all fl exible endoscopes with a lever mechanism eg ERCP scopes and ultrasound bronchoscopes should have manual cleaning monitored after each use and that all other fl exible endo scopes should have manual cleaning monitored at least once per week as recommended by Association for the Advancement of Medical Instrumentation ST79 6This recommendation aligns the minimal frequency of monitoring of endoscope cleaning with what isrecommendedforwasherdisinfectors ie minimallyonceperweek and the increased monitoring of endoscopes with lever mecha nisms ie monitored after each use would ensure that inadequate cleaning was not contributing to the risk of infection transmission The recent infectious outbreaks associated with fl exible endoscopes9 17and recent data suggesting that vaginal and rectal ultrasound probes may be vectors for bacterial and human papil loma virus HPV transmission42 45have drawn a lot of attention to problems with reprocessing of these medical devices The key issues related to reprocessing of these 2 medical devices will be re viewed to highlight what health care staff can do to reduce the risk of infection transmission INTRACAVITARY ULTRASOUND PROBES Thereareawidevarietyofintracavitaryultrasoundprobes ICUPs commercially available Each of these ICUPs has 3 basic compo nents includingtheultrasoundprobe thehandle andtheelectrical cord The probe portion enters a body cavity whereas the handle andelectricalcorddonot Reprocessingguidelines4 6categorizeICUPs as semicritical devices based on the Spaulding classifi cation but thereisconfusionregardingtheproperreprocessingandHLDof the handle component Recent publications suggest that contamina tion of the probe42 44and probe handle is frequent 80 5 of nondecontaminated handles were contaminated after full reprocessing 43despite the use of sheaths or covers during proce dures Potential pathogens such as Staphylococcus aureus S saprophyticus andShaemolyticushavebeendetectedonvaginalprobe handles after HLD of the probe only 43Furthermore a study by Casalegno et al42demonstrated that 3 of vaginal probes that were sheathed during the procedure were still contaminated with high risk HPV post HLD The HPV contamination of vaginal probes post HLDisfurthercompoundedbytherecentreportfromMeyersetal 45 who provide data showing that HPV16 is not adequately killed by 2 4 glutaraldehyde or 0 5 orthophthalaldehyde These fi ndings demonstrate the importance of adequate cleaning and HLD of both the handle as well as the probe even if sheaths are used during the clinical procedure The recent publications documenting poor or no cleaning and disinfection of ultrasound probes43 44highlights the need for proper staff education and internal audits to ensure compliance with proper reprocessing of these medical devices Although full immersion cleaning is preferred 4minimally an appropriate cleaning wipe of both the handle and probe followed by an effective HLD method for both the probe and the handle are needed for adequate reprocess ing of ICUPs There have been published studies to show the effectiveness of novel automated systems based on nebulized hy drogen peroxide46or ultraviolet C exposure47 approved in Canada and Australia but not the United States that provided effective dis infection of the ultrasound probe and handle These automated disinfection processes are alternatives that reduce the risk of staff exposure to aldehydes however they are not available in all coun tries These automated systems still require the probe and handle to be cleaned before the automated disinfection process FLEXIBLE DUODENOSCOPES There have been an increasing number of infectious outbreaks associated with multiantibiotic resistant bacteria 9 17The recent e43M J Alfa American Journal of Infection Control 44 2016 e41 e45 review by Kenters et al8indicated that of 19 outbreaks related to manual or automated reprocessing there were 8 out of 19 where cleaning was inadequate and 4 out of 19 where there was improp er drying In the outbreak reported by Aumeran et al 10debris was visible under the duodenoscope elevator lever refl ecting the gross inadequacy of manual cleaning and the need for special attention to this area However there are some published reports where the site indicated they followed the MIFU and stil