ASSESSING THE RISK OF DISEASE TRANSMISSION ......ASSESSING THE RISK OF DISEASE TRANSMISSION WHEN THERE IS A POSSIBLE FAILURE OF DISINFECTION OR STERILIZATION David Jay Weber, M.D.,

ASSESSING THE RISK OF DISEASE TRANSMISSION

WHEN THERE IS A POSSIBLE FAILURE OF

DISINFECTION OR STERILIZATION

David Jay Weber, M.D., M.P.H.

Professor of Medicine, Pediatrics & Epidemiology

Associate Chief Medical Officer, UNC Health Care

Medical Director, Hospital Epidemiology & Occupational Health

University of North Carolina, Chapel Hill

LECTURE OBJECTIVES

Understand why endoscopes are the medical devices that most

commonly are involved in outbreaks and pseudo-outbreaks

Understand the most common reasons for failure to properly

disinfect or sterilize an endoscope

Understand how to manage the situation when there is a failure to

properly disinfect or sterilize an endoscope (or another medical

device)

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Disclosures: Speakers bureau = Merck, Pfizer; Consultation = Merck, Pfizer,

Germitec, PAI, Johnson and Johnson

GI ENDOSCOPES AND BRONCHOSCOPES

Widely used for diagnostic and therapeutic procedures

Endoscope contamination during use (GI 109 in/105 out)

Semicritical items require high-level disinfection minimally

Most flexible scopes require low temperature disinfection

Inappropriate cleaning and disinfection has lead to multiple

outbreaks of cross-transmission (and multiple pseudo-outbreaks)

Medical device most commonly linked to cross-transmission

FREQUENCY OF

ENDOSCOPIC PROCEDURES, US

Procedure Total Procedures Inpatient Procedures,

2009

Outpatient Procedures,

2006

All procedures 101,262,000 47,962,000 53,300,000

Endoscopy, small

intestines

4,562,000 1,095,000 3,467,000

Endoscopy, large

intestines

6,266,000 525,000 5,741,000

Bronchoscopy 442,000 269,000 173,000

Cystoscopy 881,000 130,000 751,000

Hysteroscopy --- Not available 313,000

Arthroscopy, knee --- Not available 956,000

VA-ASSOCIATED LOOK-BACK INVESTIGATIONS AS A

RESULT OF IMPROPER REPROCESSING

January 2008 to February 2009: ENT endoscopes were cleaned using sanitizing

cloths and did not undergo high-level disinfection in accordance with

manufacturer’s and CDC recommendations (1,104 patients notified)

February 2004 to January 2009: ENT endoscopes wiped off, placed on a clean towel

saturated with 1:6 Waxide dilution for 10 min instead of manufacturer’s

recommended 1:128 dilution for general disinfection; wiped with a clean cloth

saturated with Hibiclens, rinsed under warm running tap water, dried, and wiped

twice with 70% isopropyl alcohol (297 patients notified)

1 December 2008: Patient underwent colonoscopy and blood noted in auxiliary

water tubing (AWT), used for irrigation. A required one way valve was absent and

two components of the AWT system were not disinfected or discarded according to

manufacturer’s instructions (6,805 patients notified)

Colonoscope AWT was not reprocessed after each patient, but rather only rinsed

with sterile water and never sent to Sterile Processing Department for reprocessing

(patients notified 2,531)

Holodniy M, et al. ICHE 2012;33:649-656

VA-ASSOCIATED LOOK-BACK INVESTIGATIONS AS A

RESULT OF IMPROPER REPROCESSING

Holodniy M, et al. ICHE 2012;33:649-656

Rutala WA, Weber DJ. ICHE 2007;28:146-155

OUTBREAKS AND PSEUDO-OUTBREAKS DUE TO

IMPROPERLY DISINFECTED BRONCHOSCOPES

0

2

4

6

8

10

12

14

1975-79 1980-84 1985-89 1990-94 1995-99 2000-04 2005-09 2010-14

Weber DJ, Rutala WA. 2001;ICHE 22:403 – Weber DJ, Rutala WA. ICHE 2012;33:230

PATIENTS EXPOSED TO ENDOSCOPY-

RELATED CONTAMINATION, 1974-2005

Seoane-Vazquez E, et al. Endoscopy 2007;39:742-745

RATIO OF NUMBER OF PATIENTS CONTAMINATED

TO NUMBER OF PATIENTS EXPOSED, 1974-2004

Seoane-Vazquez E, et al. Endoscopy 2007;39:742-745

INFECTIONS ASSOCIATED

WITH UPPER GI ENDOSCOPY

Kovaleva J, et al. Clin Microbiol Rev 2013;26:231

FEATURES OF ENDOSCOPES THAT

PREDISPOSE TO DISINFECTION FAILURES

Require low temperature disinfection

Long narrow lumens, right angle turns, blind lumens

May be heavily contaminated with pathogens

Use of AERs has led to a new set of problems Kovaleva J. Clin Microbiol Rev 2013;26:231

ENDOSCOPE REPROCESSING Multi-Society Guideline on Endoscope Reprocessing, 2011

PRECLEAN-point-of-use remove debris by wiping exterior and aspiration of

detergent through air/water and biopsy channels

CLEAN-mechanically cleaned with water and enzymatic cleaner

HLD/STERILIZE-immerse scope and perfuse HLD/sterilant through all channels

for exposure time (>2% glut at 20m at 20oC). If AER used, review model-specific

reprocessing protocols from both the endoscope and AER manufacturer

RINSE-scope and channels rinsed with sterile water, filtered water, or tap water.

Flush channels with alcohol and dry

DRY-use forced air to dry insertion tube and channels

STORE-hang in vertical position to facilitate drying; stored in a manner to protect

from contamination

STEPS IN THE DISINFECTION PROCESS

AND MECHANISMS OF FAILURE

Murphy Was an ICP!

Murphy’s Law

“Whatever can go wrong will go wrong”

Corollary

“…in the worst possible way at the worst possible time”

PROTOCOL FOR EXPOSURE INVESTIGATION AFTER

A FAILURE OF DISINFECTION OR STERILIZATION



Step 1 - Confirm failure of sterilization or disinfection reprocessing

Confirm that the suspected failure did, in fact, occur.

IP must review the circumstances of the reported failure including: the time and date of

the possible failure; type of D/S method; and evidence of process parameters

(printout) and results of physical, chemical and/or biological indicators

If the initial evaluation reveals that no medical items that were potentially inadequately

processed were used in patient care, there is no patient safety issue involved

Then one can limit the evaluation to determining if the disinfection/sterilization process

failed and correcting the processing error

All potentially inadequately processed items must, of course, be reprocessed

If a disinfection/sterilization failure is not confirmed, the investigation may be concluded



Step 2 - Embargo improperly D/S items

If a D/S failure has occurred, one should immediately embargo any medical

items that may not have been appropriately D/S

All items since the last successful processing (as demonstrated by process

measures and/or physical, chemical, or biological indicators) should be

embargoed.

Retrieving all items may require visiting all areas where the medical/surgical

items may be stored or used including CP, ORs, community-based practices,

storerooms, etc

Step 3 - Do not use questionable D/S unit (e.g., sterilizer, AET)

The incriminated D/S unit should be immediately placed off line and not used for

D/S of medical or surgical devices until its proper function can be assured

This may involve several runs with assessment of process parameters and

physical, chemical and/or biological indicators

Medical engineering or the manufacturer’s representative usually performs

repairs and evaluation of the unit





Step 4 - Inform key stakeholders

All key stakeholders should be informed of the problem

Risk management

Medical/nursing director of the involved units (e.g., OB, GI)

Personnel involved in disinfection/sterilization

If is often easier to arrange a face-to-face conference to assure complete

transmission of the facts with feedback than to use email or telephone

consultation



Step 5 – Conduct a complete and thorough evaluation of the cause of

the disinfection/sterilization failure

An IP should review the exact circumstances of the possible D/S failure including

the dates and results of all process measures and physical, chemical and

biologic indicators far enough back in time to assess date of first possible

malfunction

Common problems with AERs have included failure to properly clean the item,

set the correct duration of exposure to the high level disinfectant, attach the

channel connectors properly, and use of the correct channel connectors

Failure to Follow Disinfection and

Sterilization Principles

Step 6 – Prepare a line listing of potentially exposed patients

Once a failure of D/S has been documented, it is important to initiate the

evaluation of potential patient exposures

First step is to create a line listing of all possible patients who may have been

exposed to possibly contaminated medical/surgical devices

Patient name, identification number, date(s) of exposure, contaminated

device used, underlying risk factors for infection, development of HAIs

(pathogen, body site), and other potentially adverse events



Step 7 – Assess whether D/S failure increases patient risk for infection

Once a failure of D/S process has been documented with possible exposure to a

contaminated item, it is crucial to determine whether in fact the failure could

result in an adverse patient event.

For example, 3 min for flash sterilization rather than 4 min. Would not consider 3

min flash sterilization cycle as representing a patient hazard.

Assessing risk should always include a review of the scientific literature and

national guidelines



Step 8 - Inform expanded list of stakeholders

All stakeholders should be informed of the progress of the investigation,

especially if an increased risk to patients is possible or documented

Risk management

Medical/nursing director of the involved units (e.g., OB, GI)

Personnel involved in disinfection/sterilization

Public relations, healthcare administration, and legal

A press release should be prepared in case of need and a spokesperson

appointed



Step 9 - Develop hypothesis for D/S failure and initiate corrective

action Corrective actions (e.g., reset timer, monitor concentration of HLD) should be

initiated to correct the deficiencies in reprocessing

Reprocessing of any item that may not have been appropriately

disinfected/sterilized must be done



Step 10 – Develop a method to assess potential adverse patient events

Initiate a more detailed study, if necessary, of possible adverse outcomes in

patients

This may entail designing a prospective cohort study

This may require reviewing medical records and/or examining patients for

infections, chemical reactions, or other adverse events

Specific laboratory tests may be necessary such as testing source patients and

exposed persons for bloodborne pathogens such as HIV, HBV, and HCV



Step 11 – Consider notification of appropriate state and federal

authorities

In conjunction with the legal department, notify state and federal authorities if

required by regulation or law



Step 12 - Consider patient notification

Consider whether patients should be notified of the disinfection failure

If it is determined the failure could result in adverse patient events, then patients

should be notified

Determine who will notify the patients: Patient’s local medical provider, risk

management, attending physician at the time of failure, ICP

One should develop a script to be used in notification to ensure all patients

receive the same information

Notification may be accomplished by a face-to-face meeting, phone or mail

More than one method may be used to ensure complete notification



Step 12 (continued) Notification should include: an assessment of risk, possible adverse events that

may occur, symptoms and signs of the adverse event, time period for the adverse event, risk to other contacts, possible prophylactic therapy (risks and benefits) and recommended medical follow-up

The healthcare facility must decide who will provide these services and whether the facility will cover the cost of care.

In general, we believe that if the facility was responsible for the failure then it should provide these services at no patient charge

However, it the exposure resulted from failures outside the institution (receipt by the facility of inadequately sterilized devices), then the facility may want to offer the services but at patient expense or causative party’s expense (e.g., manufacturer)

ESTIMATING RISK OF

DISEASE TRANSMISSION I

Scenario: Endoscopes were processed in an AER using OPA for 2m rather than the recommended 12m. The HLD exposure time in the AER was incorrectly reset by the biomedical engineer to 2min 10 months ago. During that period of time there were 2,134 patients that received GI endoscopy procedures. All the endoscopes were reprocessed in the same AER.

Can estimate the per patient risk for HIV as follows:

HIV prevalence in the US population: 0.37%, ~4:1000, ~4x10-3

Risk of transmission (via mm): 0.09%, 1:1000, 1x10-3

Efficacy of AER without HLD: 99.999%, 1:100,000, 1x10-3

Efficacy or OPA against HIV in 2m: 99.999%, 1:100,000, 1x10-5

Effect of HIV drying: 99%, 1:100, 1x10-2

Individual risk = ~4 x 10-16 (4 in 10 quadrillion)

Risk analysis of surgical instruments inside a Sterisen container that had been

autoclaved on a gravity cycle rather than on the recommended pre-vacuum cycle,

potentially exposing 72 patients who underwent surgery with the instruments

Donskey CJ, et al. Antimicrob Resistance & Infect Control 2014;3:4

LIFETIME ODDS OF DEATH FOR SELECTED

CAUSES, US, 2009

Type of injury or event Lifetime odds of deaths

Cancer 1 in 7

Intentional self harm 1 in 106

Motor vehicle incidence 1 in 108

Falls 1 in 158

Pedestrian 1 in 749

Accidental drowning and submersion 1 in 1,112

Contact with hornets, wasps, and bees 1 in 71,107

Bitten or struck b dog 1 in 122,216

Cataclysmic storm 1 in 126,158

Lightning 1 in 126,158

http://www.nsc.org/news_resources/injury_and_death_statistics/Pages/TheOddsofDyingFrom.aspx

DECISIONS WHETHER TO NOTIFY PATIENTS OF

EXPOSURE TO CJD CONTAMINATED INSTRUMENTS

Belay ED, et al. ICHE 2013;34:1272-1280



Step 13 – If patients are notified, consider whether such patients

require medical evaluation for possible post-exposure prophylaxis

(PEP) with appropriate anti-infectives

Consider whether follow-up to infection (e.g., HIV, HBV, HCV) should be

offered

Consider duration of follow-up

Decide on who will cover the costs of PEP (facility, insurance, patient)

SAMPLES PATIENT NOTIFICATION LETTER

AND PRESS RELEASE

Rutala WA, Weber DJ. ICHE 2007;28:146-155



Step 14 - Develop a detailed plan to prevent similar failures in the

future

Once the problem leading to the D/S failure has been identified and corrective

action initiated, it is essential to assess whether these interventions have

eliminated the problem over the long-term

This may require long-term surveillance, changes in current policies or

procedures, development of new policies or procedures, evaluation of current

equipment, etc



Step 15 - -Perform after-action report

A report of the event should be prepared for presentation to the appropriate

healthcare system committees

Consideration should be given to publishing the evaluation it it provides a

contribution to the scientific literature

CONCLUSIONS

Endoscopy is a common medical procedure

Endoscopes represent the greatest challenge for proper cleaning

and disinfection

Multiple outbreaks and pseudo-outbreaks have resulted from the

failure to properly disinfect or sterilize endoscopes

A published step-by-step method for managing the failure

disinfection can be used to aid in outbreak management

If the risk of infection is sufficiently low, the healthcare facility may

choose not to notify the patient

THANK YOU!!

ASSESSING THE RISK OF DISEASE TRANSMISSION ......ASSESSING THE RISK OF DISEASE TRANSMISSION WHEN THERE IS A POSSIBLE FAILURE OF DISINFECTION OR STERILIZATION David Jay Weber, M.D.,

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