1. Copyright © 2004 WA Rutala Disinfection and Sterilization: Issues and Controversies William A. Rutala, Ph.D., M.P.H. University of North Carolina (UNC) Health Care System and UNC at Chapel Hill, NC

2. Copyright © 2004 WA Rutala Disinfection and Sterilization: Issues and Controversies l Methods in Disinfection Endoscopes/AERs, endocavitary probes, emerging pathogens l Methods in Sterilization CJD l Issues and Controversies Surface disinfection, CJD, glutaraldehyde exposure time (45m/25 o C vs 20m/20 o C), endoscope rinse water

3. Copyright © 2004 WA Rutala Disinfection and Sterilization in Healthcare Facilities WA Rutala, DJ Weber, and HICPAC, In press l Overview Last CDC guideline in 1985 219 pages (>130 pages preamble, 20 pages recommendations, glossary of terms, tables, >900 references) Evidence-based guideline (search of the literature using Medline)

4. Copyright © 2004 WA Rutala Efficacy of Disinfection/Sterilization Influencing Factors Cleaning of the object Organic and inorganic load present Type and level of microbial contamination Concentration of and exposure time to disinfectant/sterilant Nature of the object Temperature and relative humidity

5. Copyright © 2004 WA Rutala Decreasing Order of Resistance of Microorganisms to Disinfectants/Sterilants Prions Spores Mycobacteria Non-Enveloped Viruses Fungi Bacteria Enveloped Viruses

6. Copyright © 2004 WA Rutala Disinfection and Sterilization EH Spaulding believed that how an object will be disinfected depended on the object’s intended use. CRITICAL - objects which enter normally sterile tissue or the vascular system or through which blood flows should be sterile. SEMICRITICAL - objects that touch mucous membranes or skin that is not intact require a disinfection process ( high-level disinfection[HLD] ) that kills all microorganisms but high numbers of bacterial spores. NONCRITICAL -objects that touch only intact skin require low-level disinfection.

7. Copyright © 2004 WA Rutala Processing “Critical” Patient Care Objects Classification: Critical objects enter normally sterile tissue or vascular system, or through which blood flows. Object:Sterility. Level germicidal action:Kill all microorganisms, including bacterial spores. Examples:Surgical instruments and devices; cardiac catheters; implants; etc. Method: Steam, gas, hydrogen peroxide plasma or chemical sterilization.

8. Copyright © 2004 WA Rutala Critical Objects l Surgical instruments l Cardiac catheters l Implants

9. Copyright © 2004 WA Rutala Chemical Sterilization of “Critical Objects” Glutaraldehyde (> 2.0%) Hydrogen peroxide-HP (7.5%) Peracetic acid-PA (0.2%) HP (1.0%) and PA (0.08%) HP (7.5%) and PA (0.23%) Glut (1.12%) and Phenol/phenate (1.93%) _______________________________________________ Exposure time per manufacturers’ recommendations

10. Copyright © 2004 WA Rutala

11. Processing “Semicritical” Patient Care Objects Classification:Semicritical objects come in contact with mucous membranes or skin that is not intact. Object:Free of all microorganisms except high numbers of bacterial spores. Level germicidal action:Kills all microorganisms except high numbers of bacterial spores. Examples:Respiratory therapy and anesthesia equipment, GI endoscopes, thermometer, etc. Method:High-level disinfection

12. Copyright © 2004 WA Rutala Semicritical Items l Endoscopes l Respiratory therapy equipment l Anesthesia equipment l Endocavitary probes l Tonometers l Diaphragm fitting rings

13. Copyright © 2004 WA Rutala High Level Disinfection of “Semicritical Objects” Exposure Time > 12 m-30m, 20 o C Germicide Concentration_____ Glutaraldehyde > 2.0% Ortho-phthalaldehyde (12 m) 0.55% Hydrogen peroxide* 7.5% Hydrogen peroxide and peracetic acid* 1.0%/0.08% Hydrogen peroxide and peracetic acid* 7.5%/0.23% Hypochorite (free chlorine)* 650-675 ppm Glut and phenol/phenate** 1.21%/1.93%___ * May cause cosmetic and functional damage; **efficacy not verified

14. Copyright © 2004 WA Rutala Processing “Noncritical” Patient Care Objects Classification:Noncritical objects will not come in contact with mucous membranes or skin that is not intact. Object:Can be expected to be contaminated with some microorganisms. Level germicidal action:Kill vegetative bacteria, fungi and lipid viruses. Examples:Bedpans; crutches; bed rails; EKG leads; bedside tables; walls, floors and furniture. Method:Low-level disinfection

15. Copyright © 2004 WA Rutala Low-Level Disinfection for “Noncritical” Objects Exposure time > 1 min Germicide Use Concentration Ethyl or isopropyl alcohol70-90% Chlorine100ppm (1:500 dilution) Phenolic UD IodophorUD Quaternary ammonium UD _____________________________________ UD=Manufacturer’s recommended use dilution

16. Copyright © 2004 WA Rutala Disinfectants for Surface Disinfection Controversy l Noncritical Surfaces Medical equipment surfaces (BP cuff, stethoscopes)  May frequently become contaminated with patient material  Repeatedly touched by health care personnel  Disinfectant/detergent should be used Housekeeping surfaces (bed rails, bedside tables)  May play a theoretical but less significant role in diseases transmission  Disinfectants/detergents may be used (II) and detergents (non-patient care areas)

17. Copyright © 2004 WA Rutala Use of Disinfectants for Noncritical Items/Surfaces l Disinfect noncritical medical equipment with disinfectant at the proper use-dilution and a contact time of at least 1 min l Frequency for disinfecting items/surfaces should comply with facility policies and minimally when visibly soiled and on a regular basis l Disinfect noncritical patient-care items if used on a patient on Contact Precautions before use by another patient

18. Copyright © 2004 WA Rutala New Methods in Disinfection

19. Copyright © 2004 WA Rutala New FDA-Cleared Sterilants l “Old” > 2% Glut, 7.5% HP, 1.0% HP and 0.08% PA l New 1.21% glut and 1.93% phenol/phenate (HLD-20 m at 25 o C) 0.55% ortho-phthalaldehyde (HLD-12 m) 7.35% HP and 0.23% PA (HLD-15 m) 2.5% Glut (HLD-5 m at 35 o C) Hypochlorite (650-675ppm free chlorine) l Ensure antimicrobial activity and material compatibility

20. Copyright © 2004 WA Rutala Glutaraldehyde l Advantages Numerous use studies published Relatively inexpensive Excellent materials compatibility l Disadvantages Respiratory irritation from vapor Pungent and irritating odor Relatively slow mycobactericidal activity Coagulate blood and fix tissues to surfaces Allergic contact dermatitis

21. Copyright © 2004 WA Rutala Ortho-phthalaldehyde Advantages l Fast acting HLD l No activation l Excellent materials compatibility l Not a known irritant to eyes and nasal passages l Weak odor Disadvantages l Stains protein gray l Cost ($30/gal);but lower reprocessing costs-soak time, devices per gal) l Slow sporicidal activity l Eye irritation with contact

22. Copyright © 2004 WA Rutala Comparison of Glutaraldehyde and OPA >2.0% Glutaraldehyde l HLD: 45 min at 25 o C l Needs activator l 14 day use life l 2 year shelf life l ACGIH ceiling limit, 0.05ppm l Strong odor l MEC, 1.5% l Cost - $10/gallon 0.55% Ortho-phthalaldehyde l HLD: 12 min at 20 o C l No activator needed l 14 day use life l 2 year shelf life l No ACGIH or OSHA limit l Weak odor l MEC, 0.3% l Cost - $30/gallon

24. Copyright © 2004 WA Rutala Ortho-phthalaldehyde (OPA) New Contraindications for OPA l Repeated exposure to OPA, following manual reprocessing of urological instruments, may have resulted in hypersensitivity in some patients with a history of bladder cancer undergoing repeated cystoscopy. l Out of approximately 1 million urological procedures, there have been reports of 24 patients who have experience ‘anaphylaxis-like’ reactions after repeated cystoscopy (typically after 4-9 treatments). l Risk control measures: residues of OPA minimized; and contraindicated for reprocessing of urological instruments used on patients with history of bladder cancer.

25. Copyright © 2004 WA Rutala Hydrogen Peroxide l Advantages No activation required Enhanced removal of organisms No disposal issues No odor or irritation issues Does not coagulate blood or fix tissues to surfaces Use studies published l Disadvantages Material compatibility concerns for brass, zinc, copper, and nickel/silver plating (cosmetic and functional damage) Eye damage with contact

26. Copyright © 2004 WA Rutala Peracetic Acid/Hydrogen Peroxide l Advantages No activation required No odor or irritation issues Effective in the presence of organic matter l Disadvantages Material compatibility issues for lead, brass, copper, zinc (cosmetic and functional damage) Limited clinical use Potential for eye and skin damage

27. Copyright © 2004 WA Rutala Disinfection and Sterilization of Emerging Pathogens

28. Copyright © 2004 WA Rutala Disinfection and Sterilization of Emerging Pathogens l Hepatitis C virus l Clostridium difficile l Cryptosporidium l Helicobacter pylori l E.coli 0157:H7 l Antibiotic-resistant microbes (MDR-TB, VRE, MRSA) l SARS Coronavirus l Bioterrorism agents (anthrax, plague, smallpox)

29. Copyright © 2004 WA Rutala Disinfection and Sterilization of Emerging Pathogens Standard disinfection and sterilization procedures for patient care equipment are adequate to sterilize or disinfect instruments or devices contaminated with blood and other body fluids from persons infected with emerging pathogens

30. Copyright © 2004 WA Rutala Endoscopes/AERS

31. Copyright © 2004 WA Rutala GI ENDOSCOPES AND BRONCHOSCOPES l Widely used diagnostic and therapeutic procedure l Endoscope contamination during use (GI 10 9 in/10 5 out) l Semicritical items require high-level disinfection minimally l Inappropriate cleaning and disinfection has lead to cross- transmission l In the inanimate environment, although the incidence remains very low, endoscopes represent a risk of disease transmission

32. Copyright © 2004 WA Rutala TRANSMISSION OF INFECTION l Gastrointestinal endoscopy >300 infections transmitted 70% agents Salmonella sp. and P. aeruginosa Clinical spectrum ranged from colonization to death (~4%) l Bronchoscopy 90 infections transmitted M. tuberculosis, atypical Mycobacteria, P. aeruginosa Spach DH et al Ann Intern Med 1993: 118:117-128 and Weber DJ et al Gastroint Dis 2002;87

33. Copyright © 2004 WA Rutala ENDOSCOPE INFECTIONS l Infections traced to deficient practices Inadequate cleaning (clean all channels) Inappropriate/ineffective disinfection (time exposure, perfuse channels, test concentration) Failure to follow recommended disinfection practices (tapwater rinse) Flaws is design of endoscopes or AERs

34. Copyright © 2004 WA Rutala

35. ENDOSCOPE DISINFECTION l CLEAN-mechanically cleaned with water and enzymatic cleaner l HLD/STERILIZE-immerse scope and perfuse HLD/sterilant through all channels for at least 12 min l RINSE-scope and channels rinsed with sterile water, filtered water, or tap water followed by alcohol l DRY-use forced air to dry insertion tube and channels l STORE-prevent recontamination

36. Copyright © 2004 WA Rutala Rinse Water for HLD l Endoscopes-After HLD, rinse endoscopes and flush channels with sterile water, filtered water, or tapwater followed by a rinse with 70-90% ethyl or isopropyl alcohol l Other Semicritical Devices-After HLD, use sterile water, filtered water, or tapwater followed by an alcohol rinse for devices that contact upper respiratory tract (II). No recommendation for sterile or filtered water versus tapwater alone for devices that contact mm of rectum or vagina.

37. Copyright © 2004 WA Rutala Minimum Effective Concentration Chemical Sterilant l Dilution of chemical sterilant occurs during use l Test strips are available for monitoring MEC l Test strips for glutaraldehyde monitor 1.5% l Test strip not used to extend the use-life beyond the expiration date (date test strips when opened) l Testing frequency based on how frequently the solutions are used (used daily, test at least daily) l Record results

38. Copyright © 2004 WA Rutala

39. Automated Endoscope Reprocessors (AERs) l Advantages: automate and standardize reprocessing steps, reduce personnel exposure to chemicals, filtered tap water l Disadvantages: failure of AERs linked to outbreaks, does not eliminate precleaning, does not monitor HLD concentration l Problems: incompatible AER (side-viewing duodenoscope); biofilm buildup; contaminated AER; inadequate channel connectors l MMWR 1999;48:557. Used wrong set-up or connector l Must ensure exposure of internal surfaces with HLD/sterilant

40. Copyright © 2004 WA Rutala ENDOSCOPE SAFETY l Ensure protocols equivalent to guidelines from professional organizations (APIC, SGNA, ASGE) l Are the staff who reprocess the endoscope specifically trained in that job? l Are the staff competency tested at least annually? l Conduct IC rounds to ensure compliance with policy

41. Copyright © 2004 WA Rutala Endocavitary Probes l Probes-Transesophageal echocardiography probes, vaginal/rectal probes used in sonographic scanning l Probes with contact with mucous membranes are semicritical l Guideline recommends that a new condom/probe cover should be used to cover the probe for each patient and since covers may fail (1-80%), HLD (semicritical probes) should be performed

42. Copyright © 2004 WA Rutala New Methods in Sterilization

43. Copyright © 2004 WA Rutala Sterilization The complete elimination or destruction of all forms of microbial life and is accomplished in healthcare facilities by either physical or chemical processes

44. Copyright © 2004 WA Rutala “Ideal” Sterilization Method l Highly efficacious l Rapidly active l Strong penetrability l Materials compatibility l Non-toxic l Organic material resistance l Adaptability l Monitoring capability l Cost-effective Schneider PM. Tappi J. 1994;77:115-119

45. Copyright © 2004 WA Rutala Steam Sterilization l Advantages Non-toxic Cycle easy to control and monitor Inexpensive Rapidly microbicidal Least affected by organic/inorganic soils Rapid cycle time Penetrates medical packing, device lumens l Disadvantages Deleterious for heat labile instruments Potential for burns

46. Copyright © 2004 WA Rutala Minimum Steam Sterilization Times Time at 132 o C in Prevacuum Sterilizer ItemMinimum exposureMinimum drying time Wrapped instruments4 min30 min Textile packs4 min5 min

47. Copyright © 2004 WA Rutala Flash Sterilization l Flash originally defined as sterilization of an unwrapped object at 132 o C for 3 min at 27-28 lbs pressure in gravity l Flash used for items that must be used immediately l Acceptable for processing items that cannot be packaged, sterilized and stored before use l Because of the potential for serious infections, implanted surgical devices should not be flash sterilized unless unavoidable (e.g., orthopedic screws)

48. Copyright © 2004 WA Rutala Flash Sterilization l When flash sterilization is used, certain parameters should be met: item decontaminated; exogenous contamination prevented; sterilizer function monitored by mechanical, chemical, and biological monitors l Do not used flash sterilization for reasons of convenience, as an alternative to purchasing additional instrument sets, or to save time

49. Copyright © 2004 WA Rutala New Trends in Sterilization of Patient Equipment l Alternatives to ETO-CFC ETO-CO 2, ETO-HCFC, 100% ETO l New Low Temperature Sterilization Technology Hydrogen Peroxide Gas Plasma Peracetic Acid

50. Copyright © 2004 WA Rutala Ethylene Oxide (ETO) l Advantages Very effective at killing microorganisms Penetrates medical packaging and many plastics Compatible with most medical materials Cycle easy to control and monitor l Disadvantages Some states (CA, NY, TX) require ETO emission reduction of 90-99.9% CFC (inert gas that eliminates explosion hazard) banned after 1995 Potential hazard to patients and staff Lengthy cycle/aeration time

51. Copyright © 2004 WA Rutala Hydrogen Peroxide Gas Plasma Sterilization Advantages l Safe for the environment and health care worker; it leaves no toxic residuals l Fast - cycle time is 45-73 min and no aeration necessary l Used for heat and moisture sensitive items since process temperature 50 o C l Simple to operate, install, and monitor l Compatible with most medical devices

52. Copyright © 2004 WA Rutala Hydrogen Peroxide Gas Plasma Sterilization Disadvantages l Cellulose (paper), linens and liquids cannot be processed l Sterilization chamber is small, about 3.5ft 3 to 7.3ft 3 l Endoscopes or medical devices restrictions based on lumen internal diameter and length (see manufacturer’s recommendations) l Requires synthetic packaging (polypropylene) and special container tray

53. Copyright © 2004 WA Rutala Steris System Processor Advantages l Rapid cycle time (30-45 min) l Low temperature (50-55 o C) liquid immersion sterilization l Environmental friendly by-products (acetic acid, O 2, H 2 O) l Fully automated l No adverse health effects to operators l Compatible with wide variety of materials and instruments l Suitable for medical devices such as flexible/rigid scopes l Simulated-use and clinical trials have demonstrated excellent microbial killing and no clinical failures leading to infection

54. Copyright © 2004 WA Rutala Steris System Processor Disadvantages Potential material incompatibility (e.g., aluminum anodized coating becomes dull) Used for immersible instruments only Biological indicator may not be suitable for routine monitoring One scope or a small number of instruments can be processed in a cycle More expensive (endoscope repairs, operating costs) than HLD Point-of-use system, no long-term storage

55. Copyright © 2004 WA Rutala Conclusions l All sterilization processes effective in killing spores l Cleaning removes salts and proteins and must precede sterilization l Failure to clean or ensure exposure of microorganisms to sterilant (e.g. connectors) could affect effectiveness of sterilization process

56. Copyright © 2004 WA Rutala Recommendations Methods of Sterilization l Steam is preferred for critical items not damaged by heat l Follow the operating parameters recommended by the manufacturer l Use low temperature sterilization technologies for reprocessing critical items damaged by heat l Use immediately critical items that have been sterilized by peracetic acid immersion process (no long term storage)

57. Copyright © 2004 WA Rutala Sterilization Practices

58. Copyright © 2004 WA Rutala Sterilization Monitoring Sterilization monitored routinely by combination of mechanical, chemical, and biological parameters l Physical - cycle time, temperature, pressure l Chemical - heat or chemical sensitive inks that change color when germicidal-related parameters present l Biological - Bacillus spores that directly measure sterilization

59. Copyright © 2004 WA Rutala Biological Monitors l Steam - Geobacillus stearothermophilus l Dry heat - B. atrophaeus (formerly B. subtilis) l ETO - B. atrophaeus l New low temperature sterilization technologies Plasma sterilization (Sterrad) - G. stearothermophilus Peracetic acid - G. stearothermophilus

60. Copyright © 2004 WA Rutala Recommendations Monitoring of Sterilizers l Monitor each load with mechanical and chemical (internal and external) indicators. l Use biological indicators to monitor effectiveness of sterilizers at least weekly with spores intended for the type of sterilizer. l Use biological indicators for every load containing implantable items

61. Copyright © 2004 WA Rutala Recommendations Monitoring of Sterilizers l Following a single positive biological indicator used with a method other than steam, treat as non-sterile all items that have been processed in that sterilizer, dating back to last negative biological indicator. l Following a positive biological indicator with steam sterilization, objects, other than implantable objects, do not need to be recalled because of a single positive spore test unless the sterilizer or procedure is defective or inappropriate cycle settings. If additional spore tests remain positive, consider the items nonsterile and recall and reprocess the items from the suspect load.

62. Copyright © 2004 WA Rutala Recommendations Storage of Sterile Items l Sterile storage area should be well-ventilated area that provides protection against dust, moisture, and temperature and humidity extremes. l Sterile items should be stored so that packaging is not compromised l Sterilized items should be labeled with a load number that indicates the sterilizer used, the cycle or load number, the date of sterilization, and the expiration date (if applicable)

63. Copyright © 2004 WA Rutala Recommendations Storage of Sterile Items l Event-related shelf life recognizes that the product remains sterile until an event causes it to become contaminated (e.g., tear, wetness). Packages should be evaluated before use for lose of integrity. l Time-related shelf life (less common) considers items remain sterile for varying periods depending on the type of material used to wrap the item/tray. Once the expiration date is exceeded the pack should be reprocessed.

64. Copyright © 2004 WA Rutala Reuse of Single Use Devices

65. Copyright © 2004 WA Rutala FDA Developments l August 2000, FDA issued final SUD Enforcement Guidance. Hospitals and TPR regulated the same as original equipment manufacturer (OEM). l A device labeled for single-use only that is reprocessed is considered as a new device. Hospital is considered the manufacturer. l As a new device, all federal controls regarding the manufacture and marketing of the device apply.

66. Copyright © 2004 WA Rutala Hospital’s Options: USA l Option 1-Comply with enforcement guidance (August 14, 2000) and continue to reprocess SUDs l Option 2-Use Third Party Reprocessor (premarket requirements new for TPR as they have been using non- premarket requirements) l Option 3-avoid reuse of SUDs

67. Copyright © 2004 WA Rutala Recommendations Quality Control l Provide comprehensive and intensive training for all staff assigned to reprocess medical/surgical instruments l To achieve and maintain competency, staff should: hands-on training all work supervised until competency is documented competency testing should be conducted at commencement of employment and regularly review written reprocessing instructions to ensure compliance

68. Copyright © 2004 WA Rutala Disinfection and Sterilization: Issues and Controversies l Methods in Disinfection Endoscopes/AERs, endocavitary probes, emerging pathogens l Methods in Sterilization CJD l Issues and Controversies Surface disinfection, CJD, glutaraldehyde exposure time (45m/25 o C vs 20m/20 o C), endoscope rinse water

69. Copyright © 2004 WA Rutala Issue/Controversy Detergents or Disinfectants for Surface Disinfection?

70. Copyright © 2004 WA Rutala Detergents or Disinfectants for Environmental Cleaning l Introduction Use of noncritical items or contact with noncritical surfaces carries little risk of transmitting pathogens to patients Thus, the routine use of disinfectants to disinfect hospital floors and other surfaces (e.g., bedside tables) is controversial However, while noncritical surfaces have not been directly implicated in disease transmission, they may potentially contribute to cross-transmission by acquisition of transient hand carriage by HCW due to contact with a contaminated surface, or patient contact with contaminated surfaces or medical equipment

71. Copyright © 2004 WA Rutala Detergents or Disinfectants for Environmental Cleaning l Noncritical Surfaces Housekeeping surfaces (floors, walls, bedside tables)  May play a theoretical but less significant role in diseases transmission  Disinfectants/detergents or detergents may be used Medical equipment surfaces (BP cuff, stethoscopes)  May frequently become contaminated with patient material  Repeatedly touched by health care personnel  Disinfectant/detergent may be used

72. Copyright © 2004 WA Rutala Detergents or Disinfectants for Surface Disinfection l Justification for Using a Detergent on Floors Surfaces minor contribution to endemic HAIs No difference in HAI rates when floors cleaned with detergent No disinfectant disposal issues No occupational exposures issues Costs Use of disinfectants could select for antibiotic-resistant bacteria More aesthetically pleasing floors

73. Copyright © 2004 WA Rutala HAIs: Disinfectants vs Detergents l Dharan et al, 1999 No change in incidence of HAIs during 4 mo trial compared to preceding 12 mo; but detergents associated with increase in bacterial counts. l Danforth et al, 1987 NI rate did not differ between disinfectant (8.0/100 patients) and detergent (7.1/100 patients); 8 acute care units; 3 mo periods; phenol. l Daschner et al, 1980 No difference in NI rate in ICU over 6 mo (15.6% vs 15.5%). Comment: Studies are small, short duration and suffer from low statistical power since the outcome (HAI) is one of low frequency. Requirement for reducing HAI stringent, not met by most infection control interventions.

74. Copyright © 2004 WA Rutala Surface Disinfection: Should We Do It? l Justification for Using a Disinfectant Surfaces may contribute to transmission of epidemiologically important microbes (e.g., VRE, MRSA, C. difficile ) Needed for surfaces contaminated by blood and OPIM Disinfectants are more effective in reducing microbial load Detergents become contaminated and result in seeding the patients environment with bacteria CDC recommends disinfection of noncritical equipment and surfaces for patients on isolation precautions One product for decontamination of noncritical surfaces (that is, floors and equipment)

75. Copyright © 2004 WA Rutala Microbial Contamination of Mop Water

76. Copyright © 2004 WA Rutala Cleaning and Disinfection of Floors

77. Copyright © 2004 WA Rutala Surfaces in the Spread of Infections l In experimental settings, treatment of surfaces with germicide has been found to interrupt transmission Prevention of surface-to-human rotavirus transmission by treatment with disinfectant spray (J Clin Microbiol 1991;29:1991) Interrupts transfer of rhinovirus from environmental surfaces to hands (Appl Environ Microbiol 1993;59:1579) l Studies demonstrating reduced transmission with improved disinfection Marked reduction in C. difficile -associated diarrhea rates in BMTU during bleach use Aggressive environmental disinfection credited with eradicating VRE from Burn Center

78. Copyright © 2004 WA Rutala Detergents or Disinfectants for Surface Disinfection l Process noncritical patient-care equipment with a EPA- registered disinfectant or disinfectant/detergent at the proper use dilution and a contact time of at least 1 min. l Use disinfectant for housekeeping purposes when uncertain if cleaning personnel not able to: distinguish soiled areas containing blood from dirt; or determine when MDROs are likely in the environment.

79. Copyright © 2004 WA Rutala Issue/Controversy Recommendations for reprocessing CJD contaminated instruments based on WHO consensus or science-based?

80. Copyright © 2004 WA Rutala Creutzfeldt Jakob Disease (CJD): Disinfection and Sterilization

81. Copyright © 2004 WA Rutala CJD

82. Copyright © 2004 WA Rutala Epidemiology of CJD in the US l Degenerative neurologic disorder l CJD (a prion) incidence One death/million population No seasonal distribution, no geographic aggregation Both genders equally affected Age range 50-80+ years, average 67 l Long incubation, rapid disease progression after onset l Prions resistant to conventional disinfection/sterilization

83. Copyright © 2004 WA Rutala Prion Diseases l Etiology Prions (proteinaceous infectious agent)  No agent-specific nucleic acid  Host protein (PrP c ) converts to pathologic isoform (PrP sc ); PrP gene resides on chromosome 20  Mutation in this gene may trigger transformation  Accumulates in neural cells, disrupts function, cell death  Resistant to conventional D/S procedures

84. Copyright © 2004 WA Rutala Iatrogenic Transmission of CJD l Contaminated medical instruments Electrodes in brain (2) Neurosurgical instruments in brain (4?) l Implantation of contaminated grafts Dura mater grafts (114) Corneal grafts (2) l Use of human growth hormone (139) and gonadotropin (4)

85. Copyright © 2004 WA Rutala CJD and Medical Devices l Six cases of CJD associated with medical devices 2 confirmed cases-depth electrodes; reprocessed by benzene, alcohol and formaldehyde vapor 4 cases-CJD following brain surgery, index CJD identified-1, suspect neurosurgical instruments l Cases occurred before 1980 in Europe l No cases since 1980 and no known failure of steam sterilization

86. CJD : potential for secondary spread through contaminated surgical instruments

87. Copyright © 2004 WA Rutala CJD and Medical Devices l World Health Organization, 2000 When instruments contact high infectivity tissue, single-use instruments recommended. If single-use instruments not available, maximum safety attained by destruction of re-usable instruments. Where destruction is not practical, reusable instruments must be decontaminated by immerse in 1N NaOH and autoclaved (121 o C/30m), cleaned, rinsed and steam sterilized. After decontamination by steam and NaOH, instruments can be cleaned in automated mechanical reprocessor.

88. Copyright © 2004 WA Rutala Risks: Patient, Tissue, Device l Patient Known or suspected CJD or other TSEs Rapidly progressive dementia History of dura mater transplant, HGH injection l Tissue High risk-brain, spinal cord, eyes l Device Critical or semicritical

89. Copyright © 2004 WA Rutala CJD: Recommendations for Disinfection and Sterilization l High risk patient, high risk tissue, critical/semicritical device-special prion reprocessing l High risk patient, low/no risk tissue, critical/semicritical device-conventional D/S or special prion reprocessing l Low risk patient, high risk tissue, critical/semicritical device-conventional D/S l High risk patient, high risk tissue, noncritical device - conventional disinfection

90. Copyright © 2004 WA Rutala CJD: Disinfection and Sterilization Conclusions l Critical/SC-cleaning with special prion reprocessing NaOH and steam sterilization (e.g., 1N NaOH 1h, 121 o C 30 m) 134 o C for 18m (prevacuum) 132 o C for 60m (gravity) l No low temperature sterilization technology effective l Noncritical-four disinfectants (e.g., chlorine) effective (4 log decrease in LD 50 within 1h)

91. Copyright © 2004 WA Rutala CJD: Instrument Reprocessing l Special prion reprocessing by combination of NaOH and steam sterilization Immerse in 1N NaOH for 1 hour; remove and rinse in water, then transfer to an open pan and autoclave for 1 hour Immerse in 1N NaOH for 1 hour and heat in a gravity displacement sterilizer at 121 o C for 30 minutes l Combined use of autoclaving in sodium hydroxide has raised concerns of possible damage to autoclaves, and hazards to operators due to the caustic vapors. l Risk can be minimized by the use of polypropylene containment pans and lids.

92. Copyright © 2004 WA Rutala CJD: Instrument Reprocessing l Special prion reprocessing by combination of NaOH and steam sterilization Immerse in 1N NaOH for 1 hour; remove and rinse in water, then transfer to an open pan and autoclave for 1 hour Immerse in 1N NaOH for 1 hour and heat in a gravity displacement sterilizer at 121 o C for 30 minutes l Combined use of autoclaving in sodium hydroxide has raised concerns of possible damage to autoclaves, and hazards to operators due to the caustic fumes. l Risk can be minimized by the use of polypropylene containment pans and lids (AJIC 2003; 31:257-60).

94. Copyright © 2004 WA Rutala CJD: Disinfection and Sterilization Conclusions l Epidemiologic evidence suggest nosocomial CJD transmission via medical devices is very rare l Guidelines based on epidemiologic evidence, tissue infectivity, risk of disease via medical devices, and inactivation data l Risk assessment based on patient, tissue and device l Only critical/semicritical devices contaminated with high-risk tissue from high risk patients requires special treatment

95. Copyright © 2004 WA Rutala Prevent Patient Exposure to CJD Question: How do hospitals minimize patient exposure to neurosurgical instruments from a patient who is later given a diagnosis of CJD? Answer: Consider using the reviewed sterilization guidelines for neurosurgical instruments used on patients undergoing brain biopsy when a specific lesion (e.g., tumor) has not been demonstrated. Alternatively, neurosurgical instruments used in such cases could be disposable.

96. Copyright © 2004 WA Rutala Issue/Controversy “Science-based” guideline versus “policy-based” guideline

97. Copyright © 2004 WA Rutala “Science-based” or “Policy-based” Guideline l Science-based-recommendations based of peer-reviewed scientific studies l Policy-based-recommendations based on EPA and FDA regulations and registration claims High-level disinfection with glutaraldehyde for 20/20 (at least 33 studies support 20/20) vs 45/25; Low-level disinfection for at least 30-60 sec (at least 14 studies support 30-60 sec) vs 10 min

98. Copyright © 2004 WA Rutala “Science-based” or “Policy-based” Guideline l FDA registration protocol does not allow cleaning l Must kill 10 5 -10 6 Mtb, dried on scope, in presence of 2% horse serum, and in absence of cleaning. l All professional organization guidelines, 10-20 min glutaraldehyde l When guidelines followed, no evidence of disease transmission l Unresolved, but “science-based’ recommendation with recognition of FDA/EPA policies.

99. Copyright © 2004 WA Rutala BONUS Disinfection of Computer Keyboards l Increased use of computers in patient areas has led to contamination of keyboards as reservoirs of pathogens l Study performed to Examine the efficacy of different disinfectants on the computer keyboard Determine if there were cosmetic (key lettering removed) or functional changes after 300 wipes

100. Copyright © 2004 WA Rutala BONUS Disinfection of Computer Keyboards l All tested products were effective (>95%) in removing and/or inactivating the test pathogens (MRSA, P. aeruginosa ). No functional/cosmetic damage. l Disinfectants included: 3 quaternary ammonium compounds, 70% isopropyl alcohol, phenolic, chlorine (80ppm) l At present, recommend that keyboards be disinfected daily (for 5 sec) and when visibly soiled

101. Copyright © 2004 WA Rutala Disinfection and Sterilization: Issues and Controversies l Methods in Disinfection Endoscopes/AERs, endocavitary probes, emerging pathogens l Methods in Sterilization CJD l Issues and Controversies Surface disinfection, CJD, glutaraldehyde exposure time (45m/25 o C vs 20m/20 o C), endoscope rinse water

102. Copyright © 2004 WA Rutala Thank you

103. Copyright © 2004 WA Rutala References l Rutala WA, Weber DJ. CJD: Recommendations for disinfection and sterilization. Clin Inf Dis 2001;32:1348 l Rutala WA, Weber DJ. New disinfection and sterilization methods. Emerg Inf Dis 2001;7:348 l Rutala WA, Weber DJ, HICPAC. CDC guideline for disinfection and sterilization in healthcare facilities. In press. l Rutala WA. APIC guideline for selection and use of disinfectants. Am J Infect Control 1996;24:313