1. Prevention of Infection Due to Endoscopy
William A. Rutala, Ph.D., M.P.H.
University of North Carolina (UNC) Health Care System and UNC at Chapel Hill

2. Disclosure
This educational activity is brought to you, in part, by Advanced Sterilization Products (ASP) and Ethicon. The speaker receives an honorarium from ASP and Ethicon and must present information in compliance with FDA requirements applicable to ASP.

3. Endoscope Reprocessing Lecture Goals
Background
Infections related to endoscopy
Reprocessing of endoscopes and accessories
Cleaning
High-level disinfection/sterilization
Automated endoscope reprocessing
Quality control

4. GI ENDOSCOPES Widely used diagnostic and therapeutic procedure
Endoscope contamination during use (109 in/105 out)
Semicritical items require high-level disinfection minimally
Inappropriate cleaning and disinfection has lead to cross-transmission
In the inanimate environment, although the incidence remains very low, endoscopes represent a risk of disease transmission

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

6. Nosocomial Infections via GI Endoscopes
Observations
Number of reported infections is small, suggesting a very low incidence
Endemic transmission may go unrecognized (e.g., inadequate surveillance, low frequency, asymptomatic infections)
Spach DH. Ann Int Med 1993;118:117 and Weber DJ, Rutala, WA. Gastroint Dis 2002

7. Nosocomial Infections via GI Endoscopes
Infections traced to deficient practices
Inadequate cleaning (clean all channels)
Inappropriate/ineffective disinfection (time exposure, perfuse channels, test concentration, ineffective disinfectant, inappropriate disinfectant)
Failure to follow recommended disinfection practices (tapwater rinse)
Flaws is design of endoscopes or AERs

8. Endoscope Reprocessing: Current Status of Cleaning and Disinfection
Guidelines
Multi-Society Guideline, 11 professional organizations, 2003
Society of Gastroenterology Nurses and Associates, 2000
European Society of Gastrointestinal Endoscopy, 2000
British Society of Gastroenterology Endoscopy, 1998
Gastroenterological Society of Australia, 1999
Gastroenterological Nurses Society of Australia, 1999
American Society for Gastrointestinal Endoscopy, 1996
Association for Professional in Infection Control and Epidemiology, 2000
Centers for Disease Control and Prevention, 2008 (in press)

9. Endoscope Reprocessing, Worldwide
Worldwide, endoscopy reprocessing varies greatly
India, of 133 endoscopy centers, only 1/3 performed even a minimum disinfection (1% glut for 2 min)
Brazil, “a high standard …occur only exceptionally”
Western Europe, >30% did not adequately disinfect
Japan, found “exceedingly poor” disinfection protocols
US, 25% of endoscopes revealed >100,000 bacteria
Schembre DB. Gastroint Endoscopy 2000;10:215

10. Endoscopes

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

13. ENDOSCOPE REPROCESSING
Source of contamination for infections (36 outbreaks) transmitted by GI endoscopes from :
Cleaning-3 (12%)
Disinfection-19 (73%)
Rinse, Dry, Store-3 (12%)
Etiology unknown-11

14. ENDOSCOPE DISINFECTION
Cleaning (results in dramatic decrease in bioburden, 4-5 log10 reduction)
No brushing biopsy channel. (Schousboe M. NZ Med J 1980;92:275)
No precleaning before AER. (Hawkey PM. J Hosp Inf 1981;2:373)
Biopsy-suction channel not cleaned with a brush. (Bronowicki JP. NEJM 1997;337:237)

15. Bacterial Bioburden Associated with Endoscopes
Gastroscope, log10 CFU
Colonoscope, log10
CFU
After procedure
6.7
8.5 Gastro Nursing 1998;22:63
6.8
8.5 Am J Inf Cont 1999;27:392
9.8 Gastro Endosc 1997;48:137
After cleaning
2.0
2.3
4.8
4.3
5.1

16. Viral Bioburden from Endoscopes Used with AIDS Patients Hanson et al
Viral Bioburden from Endoscopes Used with AIDS Patients Hanson et al. Lancet 1989;2:86; Hanson et al. Thorax 1991;46:410
Dirty
Cleaned
Disinfected
Gastroscopes
HIV (PCR)
7/20
0/20
HBsAg
1/20
0/7
Bronchoscopes
HIV (cDNA)
7/7
1/10
0/10

17. ENDOSCOPE REPROCESSING
Precleaning
After removal from patient, wipe the insertion tube with a wet cloth and alternate suctioning the enzymatic cleaner and air through the biopsy/suction channel until solution clean. The air-water channel is flushed or blown out per instructions.
Transport the endoscope to the reprocessing area.
Enyzmatic cleaner should be prepared per instructions. Some data suggest enzymes are more effective cleaners than detergents. Enyzmatic cleaners must be changed after use.

18. ENDOSCOPE REPROCESSING
Cleaning
Immerse in a compatible low-sudsing, enzymatic cleaner
Wash all debris from exterior by brushing and wiping
Remove all removal parts of the endoscope and clean each reusable part separately
After exterior cleaning, brush accessible channels with appropriate-sized cleaning brush

19. ENDOSCOPE REPROCESSING
Cleaning (continued)
After each passage, rinse the brush, remove debris before reinserting. Continue until no visible debris on brush.
Attach cleaning adapters for each channel per manufacturer’s
instructions and flush with enzymatic cleaner to remove debris.
After cleaning is complete, rinse the endoscope with clean water.
Purge water from channels using forced air. Dry exterior of the endoscope with a soft, lint-free cloth.

20. ENDOSCOPE DISINFECTION
CLEAN-mechanically cleaned with water and enzymatic detergent
HLD/STERILIZE-immerse scope and perfuse HLD/sterilant through all channels for exposure time
RINSE-scope and channels rinsed with sterile water, filtered water, or tap water followed by alcohol
DRY-use forced air to dry insertion tube and channels
STORE-prevent recontamination

21. ENDOSCOPE REPROCESSING
Source of contaminations for infections (36 outbreaks) transmitted by GI endoscopes from :
Cleaning-3 (12%)
Disinfection-19 (73%)
Rinse, Dry, Store-3 (12%)
Etiology unknown-11

22. ENDOSCOPE REPROCESSING Unacceptable Disinfectants for HLD
Benzalkonium chloride
Iodophor
Hexachlorophene
Alcohol
Chlorhexidine gluconate
Cetrimide
Quaternary ammonium compounds
Glutaraldehyde (0.13%) with phenol

23. ENDOSCOPE REPROCESSING
Inappropriate disinfectants
Benzalkonium chloride (Greene WH. Gastroenterol 1974;67:912)
70% alcohol (Elson CO. Gastroenterol 1975;69:507)
QUAT (Tuffnell PG. Canad J Publ Health 1976;67:141)
Hexachlorophene (Dean AG. Lancet 1977;2:134)
Hexachlorophene (Beecham HJ. JAMA 1979;1013)
70% alcohol (Parker HW. Gastro Endos 1979;25;102)
Povidone-iodine (Low DE. Arch Intern Med 1980;1076)
Cetrimonium bromide. (Schliessler KH. Lancet 1980;2:1246)

24. ENDOSCOPE REPROCESSING
Inappropriate disinfectants
3% hexachlorophene. (Schousboe M. NZ Med J 1980;92:275)
0.5% CHG in alcohol, 0.015% CHG and 0.15% cetrimide; 87 s exposure to 2% glut. (Hawkey PM. J Hosp Inf 1981;2:373)
1% Savlon (cetrimide and CHG).(O’Connor BH. Lancet 1982;2:864)
0.0075% iodophor. (Dwyer DM. Gastroint Endosc 1987;33:84)
0.13% glut with phenol. (Classen DC. Am J Med 1988;84:590)
70% ethanol for 3 min. (Langenberg W. J Inf Dis 1990;161:507)

25. ENDOSCOPE REPROCESSING
Inappropriate disinfection
Air/water channel not exposed to glut. (Birnie GG. Gut 1983;24:171)
Air/water channel not exposed to glut. (Cryan EMJ. J Hosp Inf 1984;5:371)
No glut (water only) between patients. (Earnshaw JJ. J Hosp Inf 1985;6:95)

26. High Level Disinfection of “Semicritical Objects”
Exposure Time > 12 m-30m (US), 20oC
Germicide Concentration_____
Glutaraldehyde > 2.0%
Ortho-phthalaldehyde (12 m) %
Hydrogen peroxide* %
Hydrogen peroxide and peracetic acid* %/0.08%
Hydrogen peroxide and peracetic acid* %/0.23%
Hypochlorite (free chlorine)* ppm
Glut and phenol/phenate** %/1.93%___
*May cause cosmetic and functional damage; **efficacy not verified

27. New FDA-Cleared Sterilants/HLD
“Older”
> 2% Glut, 7.5% HP, 1.0% HP and 0.08% PA
Newer
0.55% ortho-phthalaldehyde (HLD- 5 m worldwide, 12 m in US)
0.95% glut and 1.64% phenol/phenate (HLD-20 m at 25oC)
7.5% HP and 0.23% PA (HLD-15 m)
2.5% Glut (HLD-5 m at 35oC)
Ensure antimicrobial activity and material compatibility

28. Ideal HLD/Chemical Sterilant
Rapid HLD (< 10 min)
No disinfectant residue after rinsing
Excellent material compatibility
Long shelf-life
Nontoxic (no odor or irritation issues)
No disposal problems
Monitor minimum effective concentration

29. Glutaraldehyde Numerous use studies published Relatively inexpensive
Advantages
Numerous use studies published
Relatively inexpensive
Excellent materials compatibility
Disadvantages
Respiratory irritation from vapor (ACGIH 0.05 ppm)
Pungent and irritating odor
Relatively slow mycobactericidal activity
Coagulate blood and fix tissues to surfaces

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

32. Comparison of Glutaraldehyde and OPA
HLD: 45 min at 25oC
Needs activator
14 day use life
2 year shelf life
ACGIH ceiling limit, 0.05ppm
Strong odor
MEC, 1.5%
Cost - $12/gallon
0.55% Ortho-phthalaldehyde
HLD: 12 min at 20oC
No activator needed
14 day use life
2 year shelf life
No ACGIH or OSHA limit
Weak odor
MEC, 0.3%
Cost - $30/gallon

33. OPA Research
Alfa and Sitter, OPA eliminated all microorganisms from 100 different endoscopes used in a clinical setting.
Gregory et al, OPA achieved a 6 log10 reduction of M. bovis in 5.5 min compared to 32 min for glutaraldehyde
Walsh et al, OPA effective against glutaraldehyde-resistant M. chelonae strains

35. OPA Label Claims Worldwide
1. Europe, Asia, Latin America
5 min at 20oC
2. Canada and Australia
10 min at 20oC
3. United States
12 min at 20oC
1. Antimicrobial tests support 5 min exposure time.
2. Canadian regulatory authority requires 6-log reduction in mycobacteria (5.5 m) and only 5 min intervals.
3. FDA requires 6-log reduction of mycobacteria suspended in organics and dried onto scope without cleaning

36. Ortho-phthalaldehyde (OPA) Contraindication for OPA
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.
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).
Risk control measures: residues of OPA minimized; and contraindicated for reprocessing of urological instruments used on patients with history of bladder cancer.

37. Hydrogen Peroxide Disadvantages 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
Disadvantages
Material compatibility concerns for brass, zinc, copper, and nickel/silver plating (cosmetic and functional damage)
Eye damage with contact

38. Peracetic Acid/Hydrogen Peroxide
Advantages
No activation required
No odor or irritation issues
Effective in the presence of organic matter
Disadvantages
Material compatibility issues for lead, brass, copper, zinc (both cosmetic and functional damage for 1% HP with 0.08% PA)
Limited clinical use

40. Minimum Effective Concentration (MEC) High Level Disinfectant (HLD)
Dilution of HLD occurs during use
Test strips are available for monitoring MEC
For example, test strips for glutaraldehyde monitor 1.5%
Test strip not used to extend the use-life beyond the expiration date (date test strips when opened)
Testing frequency based on how frequently the solutions are used (used daily, test at least daily)
Record results

41. Endoscope Reprocessing
Disinfectant/Sterilant
Immerse the endoscope in HLD/sterilant (at least minutes) and fill the channels with HLD/sterilant until no air bubbles are seen
Reusable endoscopic accessories that break the mucosal barrier (e.g., biopsy forceps) should be mechanically cleaned as described above and then sterilized between each patient use.
Rinsing
Rinse all surfaces and channels and removable parts with clean water to remove disinfectant. Inadequate rinsing of HLD has caused colitis.
Drying and Alcohol Flush
Purge channels with air; flush with alcohol; purge with air; dry
Store-prevent recontamination

42. ENDOSCOPE REPROCESSING
Rinse, Dry, Store
Irrigating water bottle. (Doherty DE. Dig Dis Sci 1982;27:169)
Inadequate drying (no alcohol). (Allen JI. Gastroenterol 1987;92:759)
Inadequate drying (no alcohol). (Classen DC. Am J Med 1988;84:590)

43. ENDOSCOPE REPROCESSING Rinse/Drying/ Storage after Manual Disinfection
Thoroughly rinse all surfaces and channels of the endoscope with large amounts of clean water
Filtered or sterile water is preferred but not mandatory
Inadequate rinsing of HLD has caused colitis
Purge all channels with air, flush with alcohol (assists drying), purge channels with air, dry the exterior
Hang the endoscope vertically (eg, cabinet)

44. Nosocomial Outbreaks via GI Endoscopes Infections Associated with Accessories
Biopsy forceps
Contaminated biopsy forceps. (Dwyer DM. Gastroint Endosc 1987;33:84)
Contaminated biopsy forceps (no cleaning between cases). Graham DY. Am J Gastroenterol 1988;83:974)
Biopsy forceps not sterilized (glut exposed,? time) Bronowicki JP. NEJM 1997;334:237)

45. ENDOSCOPE REPROCESSING Manual/AER HLD
High level disinfection is the standard of care for reprocessing GI endoscopes and bronchoscopes
The process can be completed manually or with an AER
Until recently no automated endoscope reprocessor (AER) substitutes for manual cleaning
For manual disinfection, immerse completely in HLD and fill each channel with the HLD
Cover the basin to prevent vaporization and use timer
Flush channels with air before removing the scope from HLD

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

47. EVOTECH w/Cleaning Claim
Product Definition:
Integrated double-bay AER
Eliminates manual cleaning
Uses New High-Level Disinfectant (HLD) with IP protection
Single-shot HLD
Automated testing of endoscope channels and minimum effective concentration of HLD
Incorporates additional features (LAN, LCD display)

48. Endoscope Processing System
Reliance™ EPS
Endoscope Processing System
Reliance™ DG
Endoscope Processing Support
Klenzyme®, CIP® 200
Reliance™ PI

49. Automatic Endoscope Reprocessors
EvoTech-integrates cleaning (FDA-cleared claim) and disinfection. Automated cleaning comparable to manual cleaning. All residual data for cleaning of the internal channels as well as external insertion tube surfaces were below the limit of <8.5ug/cm2
Reliance-requires a minimal number of connections to the endoscope channels and uses a control boot (housing apparatus the creates pressure differentials to ensure connectorless fluid flow through all channels that are accessible through the endoscope’s control handle channel ports). Data demonstrate that the soil and microbial removal effected by Reliance washing phase was equivalent to that achieved by optimal manual cleaning. Alfa, Olson, DeGagne. AJIC 2006;34:561.

50. HLD versus Sterilization for Endoscopes

51. Sterilization (S) or High-Level Disinfection (HLD)
Burns and colleagues compared S versus HLD with glut for arthroscopes and laparoscopes and found no difference (7.5/1000 procedures for S vs. 2.5/1000 procedures for HLD) Burns et al Infect Control Hosp Epidemiol 1996; 17: suppl p42
Fuselier and Mason examined S (with peracetic acid) and glut and found no clinical difference (no clinical data). S about 10 more costly than HLD. Fuselier and Mason Urology 1997; 50:337
Thus, no data S is superior to HLD

52. ENDOSCOPE REPROCESSING Staff Safety
Personal Protective Equipment
Gloves
Eye protection
Impervious gown
Personnel who use chemicals should be educated about the biologic and chemical hazards present while performing procedures that use disinfectants
Reprocessing Room
Area designated for this function with: adequate space, proper airflow and ventilation (7-15 ACH), work flow patterns

53. Disinfection of Emerging Pathogens

54. Disinfection and Sterilization of Emerging Pathogens
Hepatitis C virus
Clostridium difficile
Cryptosporidium
Helicobacter pylori
E.coli 0157:H7
SARS coronavirus
Antibiotic-resistant microbes (MDR-TB, VRE, MRSA)
Creutzfeldt-Jakob disease (no brain, eye, spinal cord contact)

55. 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

56. Clostridium difficile

57. Disinfectants and Antiseptics C
Disinfectants and Antiseptics C. difficile spores at 10 and 20 min, Rutala et al, 2006
~4 log10 reduction (3 C. difficile strains including BI-9)
Clorox, 1:10, ~6,000 ppm chlorine (but not 1:50, ~1,200 ppm)
Clorox Clean-up, ~1,910 ppm chlorine
Tilex, ~25,000 ppm chlorine
Steris 20 sterilant, 0.35% peracetic acid
Cidex, 2.4% glutaraldehyde
Cidex-OPA, 0.55% OPA
Wavicide, 2.65% glutaraldehyde
Aldahol, 3.4% glutaraldehyde and 26% alcohol

58. Control Measures C. difficile
Handwashing (soap and water) , contact precautions, and meticulous environmental cleaning (disinfect all surfaces) with an EPA-registered disinfectant should be effective in preventing the spread of the organism. McFarland et al. NEJM 1989;320:204.
In units with high endemic C. difficile infection rates or in an outbreak setting, use dilute solutions of % sodium hypochlorite (e.g., 1:10 dilution of bleach) for routine disinfection. (Category II)
For semicritical equipment, glutaraldehyde (20m), OPA (12m) and peracetic acid (12m) reliably kills C. difficile spores using normal exposure times

59. High-Level Disinfection C. difficile spores
2% glutaraldehyde is effective against C. difficile at 20 minutes
0.55% ortho-phthalaldehyde is effective against C. difficile at 10 minutes
Steris 20 is effective against C. difficile at 10 and 20 minutes

60. ENDOSCOPE SAFETY Quality Control
Ensure protocols equivalent to guidelines from professional organizations (APIC, SGNA, ASGE)
Are the staff who reprocess the endoscope specifically trained in that job?
Are the staff competency tested at least annually?
Conduct IC rounds to ensure compliance with policy
Consider microbiologic sampling of the endoscope

61. Conclusions Endoscopes represent a nosocomial hazard
Proper cleaning and disinfection will prevent nosocomial transmission
Current guidelines should be strictly followed
Compliance must be monitored
Safety and efficacy of new technologies must be validated

62. Prevention of Infection Due to Endoscopy
Background
Infections related to endoscopy
Processing of endoscopes and accessories
Cleaning
High-level disinfection/sterilization
Automated endoscope reprocessing
Quality control

64. Thank you

65. References
Rutala WA, Weber DJ. Disinfection of endoscopes: Review of new chemical sterilants for high-level disinfection. Infect Control Hosp Epidemiol 1999;20:69-76.
Rutala WA, Weber DJ. Creutzfeldt-Jakob Disease: Recommendations for disinfection and sterilization. Clin Inf Dis 2001;32:
Society of Gastroenterology Nurses and Associates. Standards
Weber DJ, WA Rutala, AJ DiMarino. Prevention of infection following gastrointestinal endoscopy. Gastro Dis. 2002;87-107
Rutala WA, Weber DJ, HICPAC. Disinfection and sterilization in healthcare facilities. MMWR. In press.