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

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.

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






Widely used diagnostic and therapeutic procedure
Endoscope contamination during use (10 9 in/10 5 out)
Semicritical items require high-level disinfection minimally
Inappropriate cleaning and disinfection has lead to crosstransmission
In the inanimate environment, although the incidence remains very low, endoscopes represent a risk of disease transmission



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: 118:117-128 and Weber DJ, Rutala WA Gastroint Dis 2002


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


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


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)


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






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


Source of contamination for infections (36 outbreaks) transmitted by GI endoscopes from 1974-2001:

Cleaning-3 (12%)

Disinfection-19 (73%)

Rinse, Dry, Store-3 (12%)

Etiology unknown-11


Cleaning (results in dramatic decrease in bioburden, 4-5 log
10 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)

After procedure
After cleaning
Gastroscope, log
10
CFU
6.7
6.8
2.0
4.8
2.3
4.3
5.1
Colonoscope, log
10
CFU
8.5
Gastro Nursing 1998;22:63
8.5
Am J Inf Cont 1999;27:392
9.8
Gastro Endosc 1997;48:137

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


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 airwater 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.


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


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.






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


Source of contaminations for infections (36 outbreaks) transmitted by GI endoscopes from 1974-2001:

Cleaning-3 (12%)

Disinfection-19 (73%)

Rinse, Dry, Store-3 (12%)

Etiology unknown-11

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


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)


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)


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)

High Level Disinfection of
“Semicritical Objects”
Exposure Time > 12 m-30m (US), 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%
Hypochlorite (free chlorine)* 650-675 ppm
Glut and phenol/phenate** 1.21%/1.93%___
*
May cause cosmetic and functional damage; **efficacy not verified




“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 25 o C)
7.5% HP and 0.23% PA (HLD-15 m)
2.5% Glut (HLD-5 m at 35 o C)
Ensure antimicrobial activity and material compatibility








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



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

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

>2.0% Glutaraldehyde



HLD: 45 min at 25 o C
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 20 o C
No activator needed
14 day use life





2 year shelf life
No ACGIH or OSHA limit
Weak odor
MEC, 0.3%
Cost - $30/gallon


Alfa and Sitter, 1994. OPA eliminated all microorganisms from 100 different endoscopes used in a clinical setting.

Gregory et al, 1999. OPA achieved a 6 log
10 reduction of
M. bovis in 5.5 min compared to 32 min for glutaraldehyde

Walsh et al, 1999. OPA effective against glutaraldehyderesistant M. chelonae strains

1. Europe, Asia, Latin America
5 min at 20 o C
2. Canada and Australia
10 min at 20 o C
3. United States
12 min at 20 o C
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

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.



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







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





Disinfectant/Sterilant


Immerse the endoscope in HLD/sterilant (at least 12-20 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
Storeprevent recontamination


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)

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)

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






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


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)

Reliance ™ DG
Klenzyme
®
, CIP
®
200
Endoscope Processing
Support
Reliance™ PI



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/cm 2
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.




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

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









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)

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

C. difficile spores at 10 and 20 min, Rutala et al, 2006

~4 log

10 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

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 5.25-6.15% 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

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


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


Background

Infections related to endoscopy

Processing of endoscopes and accessories

Cleaning

High-level disinfection/sterilization

Automated endoscope reprocessing

Quality control






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;32:1348-1356.
Society of Gastroenterology Nurses and Associates. Standards. 2000.
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.