Disinfection and Sterilization of Medical Instruments:

1. Disinfection and Sterilization ofMedical Instruments: An infection control update Lawrence F. Muscarella, Ph.D. Director of Research and Development Custom Ultrasonics, Inc. 144 Railroad Drive Ivyland, PA 18974 Tele: 215-364-8577; Fax: 215-364-7674 E-mail: LFM@myendosite.com Internet: www.myendosite.com Amityville, N.Y. January 15, 2008 A copy of this presentation is available at: www.myendosite.com/amityville.pdf

2. A 3-part lecture • Part 1: • “The reuse of syringes: Transmission of the hepatitis C virus (HCV) on Long Island”  Goal: To prevent disease transmission by learning about the sequence of events leading up to this past November’s notification of more than 628 patients of the risk of their exposure to HCV. A timeline is provided.  Some important recommendations are provided to prevent transmission of HCV and other blood-borne pathogens (i.e., HBV, HIV) during an injection (or the administration of an intravenous medication).

3. A 3-part lecture • Part 2: • “Choosing the right disinfectant to reprocess a flexible endoscope”  Goal: To learn how to determine whether a specific disinfectant – namely, a quaternary ammonium compound or 70% isopropyl alcohol – is sufficiently effective to prevent a gastrointestinal (GI) endoscope or other type of flexible endoscope from transmitting an infectious agent.

4. A 3-part lecture • Part 3: • A Question-and-Answersession about: • infection control • aseptic technique • instrument reprocessing  Ask me 3 infection control, aseptic technique, or instrument reprocessing questions now, and I will try to incorporate the answer to each into this afternoon’s presentation.

5. Part 1:“The reuse of syringes: Transmission of the hepatitis C virus (HCV) on Long Island”

6. Part 1: What happened in L.I.? • On July 15, 2004, a patient infected with HCVvisits an anesthesiologist, who practices pain management in Long Island and whom I will refer to as “Doctor A.” • Doctor A uses a new, sterile syringe to inject this patient, referred to as the source patient, with an initial dose of medicine (e.g., an anesthetic). (The source patient is the patient from whom the virus originated.) (So far, so good.) • During this injection, this syringe becomes contaminated with the source patient’s blood and HCV. (This is not entirely unexpected.)

7. Part 1: What happened in L.I.? • Doctor A reportedly reuses this HCV-contaminated syringe (but with a new, sterile needle) to re-inject the source patient with additional doses of medicine drawn from a multi-dose vial. (Uh-Oh.) • This infection-control breach reportedly resulted in this reused syringe contaminating this multi-dose vial (and its medicine) with the source patient’s infectious HCV. • This multi-dose vial, now contaminated with thesource patient’s HCV, is used by Doctor A to inject other patients with medicine, including to inject later the same day the indexpatient – the first identified patient to whom the source patient’s HCV was transmitted.

8. Part 1: What happened in L.I.? • Health officials: It was Doctor A’s reuse of syringes to re-inject patients with medicines drawn from multi-dose vials that was “likely” responsible for the confirmed transmission of the HCV from the source patient to the index patient (and possibly to other patients).   • Any of Doctor A’s patients who received an injection using medicine drawn from a potentially contaminated multi-dose vial (whether via a new, sterile or reused syringe) would be considered at risk of HCV.

9. Part 1: What happened in L.I.? • For clarification:  The sharing and reuse of syringes (or needles) on different patients was not to blame for the transmission of the HCV between at least two of Doctor A’s patients.  Rather, it was the reuse of a syringe to re-inject a patient with additional medicine from a multi-dose vial that “likely” resulted in contamination of the vial and (horizontal) transmission of HCV (from the source patient to the index patient and possibly to other patients).

10. A Timeline of Events DEC 2004  JAN 2005 JUL 2004   MAY 2006  DEC 2006 JAN 2006 JUL 2006 OCT 2006 NOV 2006 JUN 2006 DEC 2005 JAN 2007  NOV 2007 July 15, 2004:Doctor A reportedly injects the source patient with medicine, reuses the syringe, and contaminates a multi-dose medicine vial with the hepatitis C virus (HCV). Doctor A gives injections to 2 other patients on this same day, at least one of whom is subsequently determined to have been infected with HCV (the index patient).1,2 To edit the timeline, select the timeline object, and then click Ungroup on the Draw menu. January 2005:Two patients injected by Doctor A are identified through routine surveillance to be infected with HCV. Health officials become aware that Doctor A is reusing syringes and contaminated multi-dose vials. Investigators determine that Doctor A’s infection-control breaches are “likely” responsible for the infection of at least one of these two patients with HCV (i.e., patient-to-patient transmission of the HCV). 1-3,5,8 6 months Patients of Doctor A’s are not notified of the risk of patient-to-patient transmission of HCV, HBV, and HIV until November 10, 2007–34 months later. May, 2006:During a conference call, no decision is made by health officials to notify patients of the risk of their exposure to HCV.1 16 months later July, 2006:During other discussions over the next few months including another conference call, again no decision is made by health officials to notify patients of the risk of their exposure to HCV.1 2 months later October 6, 2006:Health officials decide to notify patients of the risk of HCV infection. They ask Doctor A for the patients’ names and addresses. Doctor A hires attorneys. Delays ensue and patients are not notified of this risk.1,4 3 months later November 10, 2007:Health officials notify by certified mail 628 patients who received an injection from Doctor A between 1-1-2000 to 1-15-2005. Letters inform patients of the potential for HCV infection 34 months after health officials first learned about the Doctor’s improper practices and their association with patient-to-patient transmission of HCV. The total number of “at risk” patients could rise into the “thousands.”3,6,9 13 months later Refer to the December, 2007, issue of “The Q-Net Monthly” newsletter for more information, including a list of these references.

11. Recommendations • Recommendations to prevent patient-to-patient transmission of blood-borne pathogens, such as HCV, during an injection: • Adhere to the principles of aseptic technique during the handling and filling of syringes used for injections (and IV medications). • Establish a quality assurance program that, among other considerations, monitors staff members to ensure their compliance with these principles.

12. Recommendations (cont.) • Establish an educational program that ensures staff members: • are educated on the modes of transmission of blood-borne pathogens; • understand the potential adverse consequences associated with breaches in aseptic technique, such as reusing syringes to re-inject patients using medicines from multi-dose vials. • Use a new, sterile syringe (and needle) for each patient. • Do not reuse any of these items, including partially-filled (i.e., used) syringes, among different patients. • Discard syringes (and needles) after each injection.

13. Recommendations (cont.) • Use single-dose medicine vials whenever possible. • These vials are labeled for use on one patient. ( Do not reuse single-dose vials to inject multiple patients.) • Draw medications from multi-dose vials with caution and in strict accordance with the vials’ labeling and aseptic technique. • As Doctor A’s breaches indicate, use of a multi-dose vial in violation of aseptic technique can result in disease transmission. • Discard the multi-dose vial whenever contamination is suspected, even if it is full of a medication.

14. Recommendations (cont.) • Most important:Never reuse a syringe to re-inject a patient with medication from one or more multi-dose vials. Always use a new, sterile syringe (and needle) to re-inject a patient with additional doses of medication. The reuse of syringes is contraindicated.

15. Question: Part 2:“Choosing the right disinfectant toreprocess a flexible endoscope”:How to determine whether a specificdisinfectant is sufficiently effective to prevent a GI endoscope or other type of flexible endoscope from transmitting an infectious agent.

16. Cleaning and disinfectingflexible endoscopes “Are either quaternary ammonium compounds or 70% isopropyl alcohol sufficiently effective for reprocessing GI endoscopes and other types of flexible endoscopes?” (Answer: A 3 step process)

17. 1st question to ask: “Based on the risk of infection associated with their use, into which category are GI endoscopes and other types of flexible endoscopes classified?” • ●Critical instruments: • Penetrate sterile tissue, enter the vasculature, or contact the patient’s blood. • Examples: cardiac catheters, biopsy forceps, and implants. • ●Semi-critical instruments: • Directly or indirectly contact mucous membranes or non-intact skin. • Examples: rhino-laryngoscopes, naso-pharyngo-laryngoscopes, bronchoscopes, and cystoscopes. • ●Non-critical instruments: • Do not directly contact the patient, or only touch the patient’s intact skin. • Examples: blood pressure cuffs, stethoscopes, and bedpans; and environmental surfaces, such as walls, floors, and sink tops.   TABLE 1:Classification scheme for medical instruments. Answer:GI endoscopes and other types of flexible endoscopes are used like bronchoscopes and cystoscopes – they directly or indirectly contact mucous membranes during routine use. From Table 1, GI endoscopes and other types of flexible endoscopes, therefore, are classified assemi-criticaldevices.

18. 2nd question to ask: • Sterilization: • Destroys all microorganisms, including resistant bacterial endospores. • Sporicidal, tuberculocidal, virucidal, fungicidal, and bactericidal • Uses bacterial endospores as indicators of effectiveness (i.e., ‘biological indicators’). • Examples: pressurized steam, ethylene oxide gas, hydrogen peroxide plasma • Primarily used for criticalinstruments. • Also suitable for some semi-critical instruments. • High-level disinfection (HLD): • Destroys all pathogenic microorganisms, including some bacterial endospores during short exposure times – Example: Clostridium difficile. • Destroys high numbers of bacterial endospores (sporicidal) during long exposure times. • Sporicidal (limited), tuberculocidal, virucidal, fungicidal, and bactericidal • Uses mycobacteria as indicators of effectiveness • Examples: 2% glutaraldehyde, 7.5% hydrogen peroxide, 0.55% ortho-phthalaldehyde • The minimum level of decontamination for semi-criticalinstruments • Primarily used for semi-criticalinstruments. • Also suitable for some critical instruments (laparoscopes, arthroscopes). “What is the minimum level of decontamination required for reprocessing GI endoscopes and other type of semi-criticaldevices?”  ANSWER:From Table 2, high-level disinfection (HLD) is the minimum level of decontamination required for reprocessing semi-critical devices. (Sterilization is also an option.) HLD is the therefore recommended for reprocessing GI endoscopes and other types of flexible endoscopes.  TABLE 2.The definitions, characteristics, and relative effectiveness of sterilization, high-level disinfection.

19. 3rd question to ask: “What level of disinfection (or sterilization) do quaternary ammonium compounds and 70% isopropyl alcohol achieve?” • Intermediate-level disinfection (ILD): • Destroys many types of microorganisms including resistant mycobacteria. • Not sporicidal • Tuberculocidal, virucidal, fungicidal, and bactericidal • May use mycobacteria or viruses as indicators of effectiveness. • Examples: 70% isopropyl alcohol, concentrated quaternary ammonium compounds – hospital cleaner/disinfectants with a tuberculocidal claim • Primarily used for non-criticalinstruments. • Not suitable for semi-critical (or critical) instruments. • Low-level disinfection (LLD): • Destroys some types of microorganisms. • Neither sporicidal nor tuberculocidal • Virucidal (limited), fungicidal, and bactericidal • May use the hepatitis B virus (HBV) or HIV as indicators of effectiveness • Examples: diluted quaternary ammonium compounds – hospital cleaner/disinfectants without a tuberculocidal claim • Primarily used for non-criticalinstruments. • Not suitable for semi-critical (or critical) instruments. ANSWER:From Table 3, quaternary ammonium compounds with a tuberculocidal claim and 70% isopropyl alcohol achieve intermediate-level disinfection (ILD).  From Table 3, quaternary ammonium compounds without a tuberculocidal claim achieve low-level disinfection (LLD).   Neither quaternary ammonium compounds nor 70% isopropyl alcohol achieve HLD (or sterilization). TABLE 3. The definitions, characteristics, and relative effectiveness of intermediate-level disinfection, low-level disinfection.

20. Let’s review Tables 2 and 3: • Sterilization destroysall types of microorganisms and is sporicidal (i.e., it destroys high numbers of bacterial endospores, but it may not destroy prions). • High-level disinfection (HLD)is tuberculocidal (i.e., destroys mycobacteria) and has limited sporicidal properties (i.e., destroys some bacterial endospores, such as Clostridium difficile). • Intermediate-level disinfection (ILD) is also tuberculocidal, but it is not sporicidal. • Low-level disinfection (LLD)is bactericidal (i.e., destroys vegetative bacteria), but it is neither sporicidal nor tuberculocidal. • Quaternary ammonium compounds achieve ILD and/or LLD, depending on the specific product’s label claim (Tables 2, 3). • ILD or LLD is recommended for reprocessing non-critical devices and environmental surfaces (Table 3).

21. The relative resistance of different types of microorganisms • (Table 4, continued) • Vegetative bacteria • Destroyed by sterilization, HLD, ILD, and LLD. Example:Pseudomonas aeruginosa • Lipid or medium-sized viruses • Destroyed by sterilization, HLD, ILD, and LLD Example: the hepatitis B virus, HIV • Key: • HLD = High-level disinfection; • ILD = Intermediate-level disinfection • LLD = Low-level disinfection • TABLE 4: The relative resistance of different types of microorganisms to sterilization, disinfection.In general, bacterial endospores (and prions) are the hardest to destroy, and lipid (or medium-sized) viruses the easiest to destroy. • Prions (most resistant) • May require extended, multiple sterilization cycles. • May be responsible for transmissible spongiform encephalopathies (TSEs), including nvCJD. • Bacterial endospores (very resistant) • Destroyed by sterilization. • Some bacterial endospores can also be destroyed by HLD. • Example:Bacillus (Geobacillus) stearothermophilus • Mycobacteria • Destroyed by sterilization, HLD, and ILD. • Example:Mycobacterium tuberculosis • Non-lipid or small viruses • Destroyed by sterilization, HLD, and ILD. • Example: the polio virus • Fungi (molds and yeasts) • Destroyed by sterilization, HLD, and ILD. • Some fungi are also destroyed by LLD. • Example:Candida albicans • (Table 4, continued) Decreasing resistance of microorganisms to sterilization, disinfection

22. Let’s bring the 3 answers to our 3 questions together: Conclusions: • GI endoscopes – like flexible laryngoscopes, rigid laryngoscopes (their handles and blades), bronchoscopes, cystoscopes, and hysteroscopes – are all semi-critical devices. • High-level disinfection (HLD) is the minimum level of decontamination required for semi-criticaldevices. • HLD, therefore, is recommended for GI endoscopes and other types of flexible endoscopes. • Quaternary ammonium compounds achieve intermediate-level disinfection (ILD) and/or low-level disinfection (LLD) (depending on whether labeled with a tuberculocidal claim). • 70% isopropyl alcohol achieves intermediate-level disinfection (ILD). • Neither quaternary ammonium compounds nor 70% isopropyl alcohol achieve HLD (or sterilization). • Quaternary ammonium compounds and 70% isopropyl are not sufficiently effective for reprocessing GI endoscopes and other types of flexible endoscopes. • Using either to disinfect GI endoscopes or another type of flexible endoscope is a violation of published guidelines. • Recommended procedure for GI endoscopes: • Step 1:Cleaning using an appropriate detergent (e.g., enzymatic detergent) • Step 2:High-level disinfection (or sterilization; also, rinse with bacteria-free water) • Step 3:Drying of the endoscope’s internal channels is recommended as part of a complete and validated reprocessing protocol.

23. Let’s discuss the 3 steps of effective endoscope reprocessing         

24. Figure 1.A method to determine the level of disinfection achieved by a biocidal agentused to reprocess medical instruments or surfaces, based on its label claim. Is the agent 100% sporicidal during short exposure times (e.g., 10 minutes)? YES YES Is the agent sporicidal? The agent is a sterilant, sterilizing solution NO NO Can be used to reprocess heat-sensitivecritical and semi-critical items The agent is a high-level disinfectant (e.g., 8 hour 100% sporicidal claim) YES Is the agent tuberculocidal? NO The agent is an intermediate-level disinfectant Can be used to reprocess non-critical items Is the agent bactericidal? YES NO The agent is a low-level disinfectant (e.g., a cleaner/disinfectant) • Examples: • quaternary ammonium compounds • 70% isopropyl alcohol • 2% glutaraldehyde Agent is not a disinfectant (e.g., a cleaner)

25. Questions for discussion • Are quaternary ammonium compounds acceptable for reprocessing laryngoscope blades? • What about laryngoscope handles? Are they semi-critical devices like laryngoscope blades? • Is high-level disinfection of GI endoscopes,cystoscopes, laryngoscopes, and bronchoscopes less safe than "sterilization"? • Can Cidex OPA be used to disinfect all types of flexible endoscopes? What about cystoscopes? • If a sterile sheath is used to cover a hysteroscope or vaginal probe, is a 70% alcohol wipe sufficient? • Is it necessary to reprocess flexible endoscopes in the A.M. before the first patient of the day (AORN)? • Is a 70% alcohol rinse, followed by forced air drying necessary between patient procedures? • Is GI endoscopy a risk factor for transmission of the hepatitis B, C viruses? • Does a 20 minute soak in 2% glutaraldehyde (to achieve high-level disinfection) pose a legal risk to a health care facility? • Can bacterial filters (0.1, 0.2 microns) produce "sterile" rinse water from a hospital’s tap? • Should the FDA change the labels of liquid sterilants from "sterilization" to "100% sporicidal"? • Is it practicing 2 different standards of care if a medical facility sterilizes rigid endoscopes in its operating room but high-level disinfects cystoscopes in its urology unit? • Is it necessary to monitor the microbial quality of the water used to rinse endoscopes?

26. Disinfection and Sterilization of Medical Instruments: Lawrence F. Muscarella, Ph.D. Director of Research and Development Custom Ultrasonics, Inc. 144 Railroad Drive Ivyland, PA 18974 Tele: 215-364-8577; Fax: 215-364-7674 E-mail: LFM@myendosite.com Internet: www.myendosite.com Amityville, N.Y. January 15, 2008 THE END A copy of this presentation is available at: www.myendosite.com/amityville.pdf