Part IV: Infection Prevention and Control Guideline for Flexible Gastrointestinal Endoscopy and Flexible Bronchoscopy – Issues related to reprocessing flexible endoscopes


1. Reprocessing of Flexible Endoscopes and Accessories

The complexity and temperature sensitivity of flexible endoscopes makes cleaning followed by sterilization/disinfection difficult. While sterilization may be optimal, the minimum acceptable standard for reprocessing endoscopes is high level disinfection (HLD). At all times, cleaning must precede high level disinfection. Endoscopic accessories do require sterilization.

Whenever flexible endoscopes are reprocessed, those involved in the reprocessing must adhere to the validated protocol recommended by the manufacturer of the endoscope. Table 4 provides detailed instruction, based on national and international guidelines, regarding both the specific steps and rationale for cleaning, disinfection, rinsing, drying and storage of endoscopes, regardless of the type/model. Figure 3 is a flow chart of the reprocessing steps described in Table 4.

NOTE:  The following table is a summary guide of the critical steps for the reprocessing of flexible endoscopes.  Please refer to the reprocessing manual provided by the manufacturer for each endoscope being reprocessed. Different types and models of endoscopes may require additional steps or different procedures to properly reprocess the device. Personal protective equipment should be worn at all times during reprocessing.

Table 4. Critical Steps for Reprocessing Flexible Endoscopes Footnote 36, Footnote 93, Footnote 94, Footnote 95, Footnote 96, Footnote 97, Footnote 98
Pre-Cleaning (Immediately after use in procedure room)
1. Wipe down the insertion tube of the endoscope with a soft lint-free disposable cloth or endoscope sponge soaked in freshly prepared enzymatic detergent. Reduces risk of worker and/or environmental contamination.  
2. Flush the air/water channels as per the manufacturer of the endoscope.  Flush all other channels with enzymatic detergent solution at bedside immediately post procedure, followed by air. Removes gross debris and ensures patient material is not allowed to dry, which will impair reprocessing. The correct adaptors are to be used in order to properly flush all channels according to manufacturer’s instructions.
3. Remove all detachable parts (e.g., valves) and reprocess accordingly.  Attach the water resistant cap, if appropriate.  Transport in a covered container rapidly to reprocessing area before drying of patient material occurs Prevents patient material from drying on scope and prevents environmental contamination. Reprocessing done off-site; may have long transit time so that secretions dry on device.
Leak Testing

4. Perform leak testing as per manufacturer’s instructions.

Note: If a leak is detected, the endoscope must be repaired. Follow manufacturer’s instructions.

If leaks are present, subsequent cleaning will allow fluid to enter the scope housing and cause damage. Patient material can enter scope housing and will not be accessible to cleaning; sequestered soil inhibits disinfection; the residual soil acts as a source of contamination if scope used on another patient.
Manual Cleaning & Rinsing
5. Completely immerse scope in enzymatic detergent solution. Enzymatic detergent improves cleaning ability by breaking down proteins. Immersion reduces aerosols, thereby reducing the infectious biohazard risk to reprocessing staff.
  1. Scope is not completely immersed, cleaning is not as well done.
  2. Contact time with the enzymatic detergent is not adequate.
  3. Full reprocessing of the endoscope is not completed promptly. If patient-used endoscopes are allowed to soak in enzymatic detergent or remain wet overnight, this will facilitate biofilm formation.
  4. The enzymatic detergent is not properly diluted or the required temperature for activation of the product is not respected, which can lead to inadequate product performance.
6. Clean all exterior surfaces of the endoscope using a soft lint-free cloth or endoscope sponge while keeping the endoscope immersed.  Use endoscope brushes to clean ALL channels while the scope is immersed. (NOTE: not all channels can be brushed - follow manufacturer’s recommendation for channel cleaning).  Repeat until all debris has been removed. Brushing greatly improves the efficiency of the cleaning process. Inadequate brushing leads to residual patient material that can cause disinfection failure and lead to disease transmission between patients.
Ensure that the brush used is appropriate for the type of endoscope and that the diameter of the bristle is adequate for the diameter of the channel.  Inappropriate brushes may not dislodge biological materials or may damage the inside of the channels.  Refer to the manufacturer of the endoscope for specifications of the channels.
7. Use manufacturer’s cleaning adaptors to ensure adequate enzymatic detergent is flushed through ALL channels (including the elevator wire, forward jet, 2nd therapeutic channel, balloon channel), and soak in enzymatic detergent as directed by the manufacturer of the enzymatic detergent. Residual material in any channel can pose a risk for transmitting infectious material to the next patient. If a channel is blocked, fluid will flow preferentially through other channels. Therefore, ensure fluid is flowing through all channels.  The preferred method of flushing the instrument is from umbilical end to distal end.
8. Remove the endoscope from the enzymatic detergent basin and place in a basin filled with clean water for rinsing. The enzymes are proteins and if not adequately rinsed off, can contribute to protein build-up within scope channels. Adequate removal of detergent is not achieved when an insufficient amount of rinse water is used or with used rinse water.  The pre-rinse cycle of some Automated Endoscopy Reprocessors (AERs) can be used to ensure the appropriate volume of rinsing is achieved.
9. Rinse all channels with an adequate volume of water to remove all detergent (At a minimum use approximately three times the total channel volume specific to the endoscope being reprocessed. Ensure a copious amount of water is used to remove all enzymatic detergent). The enzymes are proteins and if not adequately rinsed off, can contribute to protein build-up within scope channels. Adequate removal of detergent is not achieved when an insufficient amount of rinse water is used. The pre-rinse cycle of some AERs can be used to ensure the appropriate volume of rinsing is achieved.
10. Following the rinse, purge all endoscope channels with air to ensure removal of water. Wipe the exterior surfaces of the endoscope using a soft lint-free disposable cloth to remove excess moisture. Residual water will dilute the high level disinfectant and reduce the concentration of the disinfectant. A high level disinfectant diluted with residual water may reduce the efficacy of the disinfectant and not properly disinfect the device.
High-Level Disinfection
11. Monitor minimal effective concentration (MEC) of the high level disinfectant or sterilant if reused. Rapid test strips specific to the product being used are available for this purpose. The high level disinfectants that are reused can lose efficacy through excessive dilution and/or inactivation. Lack of monitoring can result in use of ineffective high level disinfectant concentrations and inadequate microbial killing.
12. Completely immerse the endoscope in a dedicated basin filled with an approved high level disinfectant or sterilant as per manufacturers’ instructions. Use the endoscope cleaning adaptors to fill ALL channels with adequate high level disinfectant or sterilant (including the elevator wire, forward jet, 2nd therapeutic channel, balloon channel), and soak in the high level disinfectant or sterilant as directed by the manufacturer of the product. Wipe the endoscope with a soft lint-free cloth to remove any bubbles on the surface of the endoscope.  (NOTE: If an AER is used for reprocessing Endoscopic Retrograde Cholangiopancreatography (ERCP) scopes or other specialty endoscopes, ensure that all channels can be disinfected by the AER. Otherwise the affected channels MUST be manually cleaned/disinfected prior to placing in the AER). Microbial killing needs to be effective; therefore, only disinfectants with antimycobacterial activity (e.g., high level disinfectant) or sterilants are appropriate. Disinfectants other than those approved may result in inadequate microbial killing.
13. Adequate contact time and temperature are critical; therefore, temperature of the product should be monitored and contact time should be timed accurately as per manufacturer’s recommendations.  The use of a timer should be considered. If less than the minimum effective exposure time or temperature are used, microorganisms may survive.  This increases the risk of transmitting infections.  Problems with adequate timing are frequent when manual disinfection is done because timing of exposure to a high level disinfectant is often not performed. This is not an issue with AERs as long as the AER is programmed according to the manufacturer of the high level disinfectant or sterilant instructions.  Temperature requirements still need to be respected while using an AER.
14. Following the disinfection, purge all channels with air to ensure removal of all high level disinfectant or sterilant from the endoscope and remove the endoscope from the high level disinfectant or sterilant. Residual high level disinfectant and sterilants can cause tissue damageFootnote 99. The correct adaptors are to be used in order to properly flush air through all channels according to manufacturer’s instructions to remove all high level disinfectant or sterilant from the endoscope.
15. Immerse the endoscope in a dedicated basin filled with fresh bacteria-free or sterile water.  Rinse all channels with an adequate volume of water to remove all high level disinfectant or sterilant (at a minimum use approximately three times the total channel volume specific to the endoscope being reprocessed.  Ensure a copious amount of water is used to remove all high level disinfectant or sterilant).  Refer to the high level disinfectant or sterilant manufacturer’s recommendations for appropriate rinsing procedure.  Some high level disinfectant or sterilants require several complete water exchanges.  Most AERs rinse with several liters of water. Residual high level disinfectant and sterilants can cause tissue damageFootnote 99; therefore, adequate rinsing is critical to remove all residuals. Problems with inadequate rinsing are possible when manual disinfection is done. Different endoscopes may require larger rinsing volume than others. Because the rinse volume in an AER is usually preset and cannot be reduced by the user unless initially programmed incorrectly, AERs provide more reliable rinsing, compared to manual methods where user variability is a problem.

16. Final rinse water should be sterile or bacteria-free.

Tap water can be used, but if it is, a subsequent 70-90% alcohol rinse is CRITICAL between each patient use and prior to storage.

Tap water can contain Mycobacteria, Pseudomonas and other microorganisms.  Therefore, the final rinse water should be bacteria-free (i.e., filtered through a 0.2 µm filters). Filtration can produce bacteria-free water provided there are no viruses in the water being filtered and the filters are patent. Bacterial overgrowth within flexible endoscope channels may result from tap water microorganisms in moist channels. This has led to infection transmission between patients.

17. Remove the endoscope from the rinse water and purge all channels with air to remove all remaining rinse water. Rinse all channels with 70% - 90 % alcohol (approximately 60 ml. flushed through all channels using the appropriate adaptors).

(NOTE: alcohol rinse and drying is not needed if scope is used immediately on another patient, unless the final rinse was with unfiltered tap water).

This facilitates the drying of the channels and will also kill any tap water microorganisms that might be present. Lack of drying has been associated with infection transmission between patients due to microbial overgrowth.
18. Following the alcohol rinse and prior to storing the endoscope, purge all channels with forced air. Wipe the exterior surfaces of the endoscope with an alcohol moisten soft lint-free cloth. This facilitates the drying of the channels. Lack of drying has been associated with infection transmission between patients due to microbial overgrowth.
High pressured air (compressed air) may damage the inner structures of the endoscope. Consult the manufacturer of the endoscope for more information.
19. Store endoscope uncoiled in a vertical position (i.e., hang in closed, ventilated cabinet). Store detachable and reusable parts (e.g., valves and water resistant cap) separately from scope. This facilitates drying of the scope during storage and reduces risk of recontamination. Keeping valves on during storage increases the risk that residual moisture will remain, increasing the risk of microbial overgrowth and infection.

Figure 3. Flow Chart for Endoscope Reprocessing

Figure 3. Flow Chart for Endoscope Reprocessing

* As per manufacturer of the product
** As prescribed by the manufacturer of the High Level disinfectant AND in accordance to the manufacturer of the endoscope
*** Alcohol rinse and drying is not needed if scope is used immediately on another patient, unless the final rinse was with unfiltered tap water

Text Equivalent - Figure 3 is a graphical representation of the reprocessing steps as described in Table 4.

4.1 Formation du personnel

Le retraitement des endoscopes souples comporte une étroite marge de sécurité à cause de la complexité des instruments et des procédés utilisés. Le non‑respect des recommandations de retraitement du fabricant pourrait faire en sorte que des microorganismes demeurent dans l’instrument, augmentant ainsi le risque d’infectionNote de bas de page 95. Le retraitement des endoscopes souples, comme toute activité humaine, est sujet à l’erreur, car il s’agit d’un procédé en plusieurs étapes qui est tributaire des humains et du matériel de nettoyage manuel ou automatique. La probabilité d’erreurs est accrue si le personnel qui manipule les endoscopes souples durant leur retraitement est inexpérimenté ou sans formation. Un élément majeur de la gestion de la qualité consiste à veiller à ce que le personnel en endoscopie reçoive une formation portant expressément sur le matériel utilisé et à ce qu’il y ait une vérification continue des compétences pour garantir la conformité aux protocoles. Pour que le nettoyage et la désinfection soient effectués adéquatement, il est essentiel d’avoir des employés compétents qui maintiennent une excellence constante dans leur pratiqueNote de bas de page 2, Note de bas de page 3, Note de bas de page 4, Note de bas de page 6, Note de bas de page 7, Note de bas de page 9, Note de bas de page 11, Note de bas de page 16, Note de bas de page 45, Note de bas de page 85, Note de bas de page 91, Note de bas de page 149.

L’information relative à la prévention et au contrôle des infections est une composante primordiale du programme d’orientation et de formation continue de tout le personnel, y compris les médecins, les infirmières et les techniciens qui travaillent en endoscopieNote de bas de page 6, Note de bas de page 9. Le programme d’orientation et de formation continue devrait inclure, sans toutefois s’y limiter, les éléments suivants :

  • Mécanismes de transmission des maladies,
  • Pratiques de base et précautions additionnelles,
  • Utilisation appropriée de l’équipement de protection individuelle,
  • Réglementation en matière de santé et de sécurité au travail,
  • Procédures de retraitement des endoscopes souples et de leurs accessoires,
  • Pratiques de travail sécuritaires,
  • Manipulation sécuritaire des produits chimiques utilisés dans le cadre du retraitement,
  • Gestion sécuritaire des déchets,

Un exemple de protocole de formation figure à l’annexe G.

4.2 Entretien préventif et réparations

L’évaluation périodique des endoscopes par des employés compétents peut réduire à la fois les risques pour les patients et les coûts de réparation. Les fabricants fourniront du personnel technique qualifié pour de telles évaluations et un service sur place. Les réparations devraient toujours satisfaire ou dépasser les spécifications originales du fabricant et être faites avec des pièces du constructeur d’origine du matériel. La détection des réparations mineures à faire avant que d’autres bris ne surviennent peut permettre de prévenir l’utilisation sur un patient d’un endoscope qui ne satisfait pas aux normes; elle peut aussi éviter des réparations et des coûts majeurs inutiles.

Durant le nettoyage manuel, du personnel qualifié devrait inspecter les instruments pour vérifier leur bon fonctionnement et la présence de brisNote de bas de page 4, Note de bas de page 11. Si un endoscope doit être réparé, il importe d’assurer une désinfection adéquate; si la désinfection est impossible, il faut alors suivre les précautions de manipulation indiquées par le fournisseur de service pour l’expédition d’un endoscope contaminé et conformément aux directives provinciales et fédérales du transport des marchandises dangereusesNote de bas de page 11. Lorsqu’un endoscope doit être réparé par quelqu’un d’autre que le fabricant d’origine (c.-à-d. un tiers effectuant des réparations), le fournisseur de service devrait fournir de l’information à l’effet que le nouveau produit ou le produit réparé répond aux spécifications originales du produit ou les surpasse (p. ex. si le canal d’aspiration est remplacé ou réparé, le matériau utilisé devrait être physiquement compatible avec le désinfectant de haut niveau utilisé).

1.1 Pre-Cleaning

Meticulous manual cleaning of endoscopes and accessories is critical to the success of subsequent disinfection or sterilization. Manual cleaning refers to the physical removal of organic material and/or soil. The presence of residual organic material and/or soil may protect microorganisms from penetration and destruction by germicides, therefore contributing to disinfection or sterilization failure.

The initial steps in the cleaning process begin immediately after the patient procedure to prevent drying of secretions on both the exterior surface and inner channels of the endoscopeFootnote 9, Footnote 15,. At the conclusion of the procedure, and before transporting the endoscope to the reprocessing area, the following steps need to be performed:

  • Wipe the insertion tube with a soft lint-free cloth or endoscope sponge soaked in freshly prepared enzymatic detergent.
  • Flush the air/water channels as per the endoscope manufacturer’s instructions.
  • Flush all other channels with enzymatic detergent solution at bedside immediately after the procedure, followed by flushing with air.
  • Flush all the internal channels with freshly prepared enzymatic detergent to moisten and dilute organic debris.
  • Remove all detachable parts and have them reprocessed accordingly.
  • Attach the water resistant cap (if indicated).
  • Immediately transport in a covered container to the reprocessing area.

1.2 Leak Test

The goal of performing a leak test is to detect any physical breaks to the exterior or interior of the endoscopeFootnote 4 Footnote 60.

Leak Test

These physical breaks compromise the integrity of the endoscope and will damage the internal structures (i.e., electrical wires, light bundle, manipulation cables) of the endoscope, which are not meant to be in contact with fluids.  These breaks may also create a reservoir for microorganisms to proliferateFootnote 4.  Leak testing should be done after each procedure and prior to manual cleaning.

A leak test is performed by applying air pressure to the inside of the endoscope and by monitoring the presence of air bubbles coming from the endoscopeFootnote 4 or by the inability to maintain adequate air pressure within the endoscope.

If a leak is detected, immediately remove the endoscope from service and have the device repaired or replaced.  Refer to the manufacturer's instructions for proper decontamination and transportation of broken endoscopes. Always perform leak tests as per the manufacturer’s instructionsFootnote 4 Footnote 60.

1.3 Manual Cleaning and Rinsing

Manual cleaning of flexible endoscopes is prone to error and must therefore be done with care.

A problem that may be encountered by the reprocessing staff is unfamiliarity with all of the channels for the particular model of flexible endoscope being reprocessed. This highlights the need for staff training and ongoing competency testing and quality assurance.  It is useful to have diagrams of type/models being reprocessed in the healthcare facility that clearly identify all the channels that must be cleaned and disinfected.

The enzymatic detergent used for cleaning flexible endoscopes (follow the manufacturer’s recommendations for reconstitution and application) is a protein solution, and therefore if rinsing is not adequate after the cleaning process, there will be residual detergent protein remaining. If an inadequately rinsed endoscope is then placed in an aldehyde disinfectant, the residual detergent protein will be “fixed” within the channels and on the surface of the endoscope, possibly protecting underlying bacteria from exposure to the disinfectant.

  • After successfully carrying out the leak test, completely immerse the endoscope in a freshly prepared enzymatic detergent solution (prepared as per the manufacturer's instructions).
  • Clean all exterior surfaces of the endoscope using a soft lint-free cloth or endoscope sponge while keeping the endoscope immersed. 
  • Use endoscope brushes to clean ALL channels while the scope is immersed. (NOTE: not all channels can be brushed - follow the manufacturer’s recommendations for channel cleaning). Repeat until all debris has been removed.  Flexible endoscopes have multiple channels with different diameters, so it is essential that a variety of brushes be available for use. Brushes should be of the correct diameter and length to ensure that the bristle will make contact (provide friction) with the walls of the lumens. 
  • Use the manufacturer’s cleaning adaptors to ensure adequate enzymatic detergent is flushed through ALL channels (including the elevator wire, forward jet, 2nd therapeutic channel, balloon channel), and soak in enzymatic detergent as directed by the manufacturer of the enzymatic detergent.
  • Remove the endoscope from the enzymatic detergent basin and place in a basin filled with clean water for rinsing.
  • Rinse all channels with an adequate volume of water to remove all detergent (At a minimum use approximately three times the total channel volume specific to the endoscope being reprocessed.  Ensure a copious amount of water is used to remove all enzymatic detergent). The use of potable tap water for rinsing after endoscope cleaning is acceptable.
  • Following the rinse, purge all endoscope channels with air to ensure removal of water.  Wipe the exterior surfaces of the endoscope using a soft lint-free disposable cloth to remove excess moisture.
Manual Cleaning and Rinsing

All channels should be brushed and rinsed prior to disinfectionFootnote 1 Footnote 3 Footnote 6 Footnote 21 Footnote 47 Footnote 64 Footnote 100.

Ideally, cleaning and disinfection of endoscopes should be performed immediately after use. There may be instances where this is difficult to achieve (e.g., emergency procedures after hours). If immediate cleaning is not possible, the endoscope may be flushed and soaked in an enzymatic detergent solution until properly reprocessedFootnote 101. If the endoscope has been cleaned, but not disinfected, and left to soak, it should be thoroughly cleaned again prior to disinfection. If flexible endoscopes are inadvertently left overnight prior to cleaning, the manual cleaning stage must be performed thoroughly prior to disinfection/sterilization. As outlined in the previous discussion on biofilm formation, allowing a flexible endoscope to sit overnight with residual microorganisms and patient secretions in the channels will lead to biofilm formation that may be difficult to subsequently remove. Consult the manufacturer of the endoscope for special directives on delayed reprocessing.

Few published studies address whether washing by the automated endoscope reprocessor as part of flexible endoscope reprocessing can replace manual cleaning. One article found that the automated washing phase of the endoscope reprocessing system studied was equivalent to optimal manual cleaning for the makes and models of flexible endoscopes testedFootnote 95. As new technological advances develop and Automated Endoscope Reprocessors (AERs) with a washing cycle are marketed, there will be the need to assess the cleaning efficacy of these new devices. Until such studies are completed, cleaning needs to be done manually.

1.4 Disinfection and Sterilization

Sterilization is considered optimal, however, the minimum acceptable standard for reprocessing endoscopes is high level disinfection (HLD). Currently, most of the available flexible endoscopes are temperature sensitive and cannot undergo steam sterilization. (Note: there are some makes of bronchoscopes that can be steam sterilized, but these are not widely used). 

If a high level disinfectant is used, it is critical that exposure time, temperature and concentration of the active ingredient are consistently achieved and strictly controlled.

1.4.1 Selection of a High Level Disinfectant Product

The characteristics of an ideal liquid chemical (LC) agent used as a high level disinfectant should include broad antimicrobial spectrum, rapid onset of action, compatibility with delicate instruments, lack of toxicity for healthcare staff, patients and the environment, no odour, non-staining, unrestricted disposal, prolonged reuse and shelf life, ease of use, remains active in the presence of protein and organic material, ability to be monitored for concentration, and relatively low cost.  No currently marketed product satisfies all these criteria.  Major disadvantages include material incompatibility (e.g., peracetic acid, hydrogen peroxide) and human toxicity (e.g., glutaraldehyde)Footnote 102.

Despite their limitations, LC agents are convenient, relatively fast-acting, and universally used to reprocess flexible endoscopes and other instruments.  When selecting a high level disinfectant product, infection prevention personnel should assess their institution’s requirements (e.g., number of endoscopes processed per day, training, turnaround time required), obtain cost information, and know provincial and federal regulations regarding safe use and disposal requirements.  It is important that healthcare workers who use any high level disinfectant, be familiar with and have readily accessible, product/brand-specific Material Safety Data Sheets (MSDS) for all chemicals used, and keep current with developments in products and practice. Table 5 lists the currently approved low temperature products/methods for disinfection/sterilization of flexible endoscopes and comments regarding appropriate use.  For detailed information on advantages and disadvantages of available high level disinfectant products, the reader is referred to Best Practices for Cleaning, Disinfection and Sterilization In All Health Care SettingsFootnote 2 Footnote 12 Footnote 102.

1.4.2 Liquid Chemical Agents

The most common method for disinfection/sterilization of flexible endoscopes is the use of liquid chemical (LC) agents including glutaraldehyde, ortho-phthalaldehyde (OPA), peracetic acid, and hydrogen peroxide (see Table 5).  Glutaraldehyde has exposure threshold limit values as specified in provincial Occupational Health and Safety (OH&S) regulations and special air-handling requirements are necessary when this agent is used, due to its propensity to cause sensitization reactions in some healthcare workers. The correct contact time for the particular chemical agent used must be adhered to as indicated in Table 5. Glutaraldehyde (either alkaline or acidic) requires a minimum of 20 minutes contact time at room temperature.  Although the manufacturer recommends 45 minutes contact time at 25°C, current guidelines and expert opinion confirm that 20 minutes at room temperature (20°C) is adequate provided that thorough pre-cleaning has been performed prior to exposure to the glutaraldehydeFootnote 1 Footnote 3 Footnote 38 Footnote 40 Footnote 90 Footnote 103 Footnote 104 Footnote 105.  Ortho-phthalaldehyde (OPA) has the shortest exposure time at 10 minutes at room temperature (min 20°C), or a contact time of 5 minutes if used in AERs at a minimum temperature of 25°C. The information listed in Table 5 is current at the time of publication. Always refer to the manufacturer's instructions for product and for further details.  Ensure that a Drug Identification Number (DIN), indication that the product is licensed by Health Canada for the Canadian market, is on the product container.

1.4.3 Low Temperature Gas and Gas Plasma Sterilization

Sterilization must be performed if the endoscope enters the body through an incision, as with intraoperative enteroscopyFootnote 12 Footnote 14.  Low-temperature sterilization (<60 degrees C.) is required for temperature and moisture-sensitive critical medical devices.  All currently developed sterilization processes have limitations and these must be understood to ensure the proper application of new sterilization technologies within medical facilitiesFootnote 106.

Regardless of the sterilization method used, scrupulous manual cleaning must precede sterilization to remove organic debris and saltsFootnote 107 Footnote 108 Footnote 109 Footnote 110 Footnote 111

Ethylene oxide (ETO) has been the most widely used low-temperature sterilization process.  The compatibility of  ETO with a wide range of materials has made it the most suitable process for the majority of heat and/or moisture-sensitive medical devices, however, there are potential toxic hazards to staff , patients and the environment, as well as risks associated with handling a flammable gasFootnote 112.  The International Agency for Research on Cancer (IARC) has upgraded its classification for ETO from 2A to a group 1 (known human carcinogen)Footnote 113.  A properly designed ventilation system dedicated to removing ethylene oxide, safe workplace practices and ongoing training can minimize the worker's exposure to the productFootnote 114.

Ethylene oxide (ETO) is an acceptable method of sterilizing flexible endoscopes, however, a lengthy aeration time is required for equipment post-exposure in order to allow desorption of all residual toxic gas from the endoscope to occur.  In addition, additional steps must be taken (e.g., application of a venting valve or the removal of the water resistant cap) to ensure proper perfusion with the gas and to prevent damage due to pressure build-up.  There are specific cases for holding flexible endoscopes during this process (manufacturer’s recommendations should be followed).  Do not place flexible endoscopes in their storage cases when being sterilized using ETO

Low-temperature hydrogen peroxide gas plasma sterilization has been used in hospitals worldwide for over a decadeFootnote 115.  Unlike ETO, hydrogen peroxide is not toxic and does not leave significant residue on the sterilized instruments.  AlfaFootnote 107 Footnote 116 demonstrated difficulty in achieving sterilization of narrow lumens in the presence of serum and salt with plasma-based sterilization systems.  She also demonstrated that a lumen adaptor/booster, which supplies an additional source of hydrogen peroxide within the lumen, appears to improve the effectiveness of the plasma sterilization process.  Newer gas plasma sterilization technologies have been found to be superior to older systems and improve the margin of safety of this sterilization processFootnote 109 Footnote 117 Footnote 118 Footnote 119.

When reprocessing an endoscope with a hydrogen peroxide gas plasma sterilization process, ensure the lumens are made of Teflon® or polyethylene and that the lumens conform to the dimensions specified by the manufacturer for the specific sterilizer.  Ascertain that the endoscope is made of materials that are compatible with this reprocessing method. Should the lumens or materials not conform to the manufacturer’s recommendations, consult with the manufacturer of the endoscope for information on how to properly sterilize the device.

Table 5. High Level Disinfectants/Sterilization Methods Currently Used for Reprocessing Flexible Endoscopes
High Level Disinfection
 2% Glutaraldehyde minimum of 45 minutes at 25ºC is indicated by the manufacturers (a minimum of 20 minutes at room temperature (20ºC) is adequate according to expert opinion and published guidelines)
  • Aldehydes are protein fixatives, therefore it is critical that medical devices have been thoroughly cleaned and rinsed prior to exposing to glutaraldehyde as any residual protein will be fixed onto the surface by this high level disinfectant. Because of this protein fixing property, aldehydes should not be used for reprocessing scopes used in patients with suspect, possible, or proven prion infection.
  • Vapours from glutaraldehyde are sensitizing and work areas need to be properly ventilated to ensure levels are below threshold limit values (TLVs) specified in Occupational Health & Safety (OH&S) regulations. Use of an AER mitigates this aspect.
  • Recirculation of air in the area where the product is used is prohibited by OH&S regulations and ventilation must be to the exterior. The product Material Safety Data Sheet (MSDS) stipulates 10 fresh air exchanges/hour in the area where product is used.
  • Scheduled air quality monitoring is essential to ensure control of glutaraldehyde vapours.
  • Glutaraldehyde is reusable for 14 to 28 days (depending upon formulation).
  • Minimal effective concentration (MEC) testing is required.
  • Glutaraldehyde has a long history of use and is less expensive/gallon than other agents.
  • Disposal down the drain may be regulated in some areas.
Ortho-phthalaldehyde (OPA)

minimum of 10 minutes at room temperature (20°C);

minimum of 5 minutes at 25°C (when used with an AER)

  • OPA is an aldehyde and cross-links proteins similarly to glutaraldehyde, however it is much less active as a fixative compared to glutaraldehyde. Because of this protein fixing property, it should not be used for reprocessing scopes used in patients with suspect, possible, or proven prion infection.
  • Fumes may cause sensitization but there are fewer problems with air levels compared to vapours from glutaraldehyde. The product MSDS stipulate 10 fresh air changes/hour in the area where product is used.
  • No air quality monitoring for vapours is required.
  • OPA is reusable for 14 days.
  • MEC testing is required.
  • Rinsing after exposure to OPA is critical as OPA is hydrophobic and hard to rinse off flexible endoscopes. Use of AERs facilitates adequate rinsing post-exposure.
  • OPA is more costly than some products.

7.5% Hydrogen Peroxide

(Some 3-4% formulations have also been validated for high level disinfectant-check manufacturer’s label claims)

15 to 30 minutes at 21ºC (depending upon formulation)
  • Materials compatibility issues have been documented with brass and copper, thus the product is not widely used for flexible endoscopes.
  • MEC testing is required.
  • The product is reusable for 14 days.
0.2% Peracetic Acid 5 minutes at 30ºC or 12 minute at 50-56ºC depending on the formulation
  • No vapour issues exist (except during accidental spills).
  • Product can be disposed of down the drain.
  • Product causes cosmetic changes to aluminum anodized coating.
Ethylene Oxide (ETO) (100% formulation, or carrier gas that is not Freon® based) 30 minutes to 1 hour exposure (depending on sterilizer)
  • 8-12 hours mechanical aeration is required at 50-60°CFootnote 120.
  • Monitoring of ETO exposure levels for staff is required as per TLV in OH&S regulations. Federal regulations must be followedFootnote 114 Footnote 121.
  • Recirculation of air in the area where the product is used is prohibited by OH&S regulations and ventilation must be to the exterior.
  • Special ETO approved cases are needed for flexible endoscopes.
Gas Plasma (vaporized hydrogen peroxide) ~ 50 minutes
  • Product is safe for the environment, as there are no fumes.
  • Limitation due to poor penetration of the gas in long and narrow lumens.
  • Limitation in material compatibility.
  • Only wraps appropriate for use with gas plasma can be used.

Note: Readers are advised to check the Health Canada – Therapeutic Product Directorate (TPD) website for updated licensing information.

1.4.4 Automated Endoscope Reprocessors (AERs)

Automated endoscope reprocessors (AERs) standardize the disinfection process and decrease personnel exposure to a high level disinfectant and sterilantsFootnote 122 Footnote 123. The AER manufacturer is to provide a list of the flexible endoscopes that have been validated for reprocessing in their specific AERs, and a list of chemical disinfectants/sterilants that can be used with the AERFootnote 124.  Some AERs use dedicated single-use liquid chemical agents whereas other AERs may accommodate a range of reusable high level disinfectants.  In each case, the AER manufacturer’s device-specific instructions must be followed and only endoscopes that are compatible with the AER (as indicated by the endoscope and AER manufacturer) should be reprocessed by these methods.

If the AER manufacturer recommends that connectors be used for flexible endoscopes reprocessed in the AER, then the correct connector for the specific endoscope being reprocessed must  be usedFootnote 124 Footnote 125 Footnote 126. Current AERs will always have disinfection and rinse cycles. In addition to these basic disinfection and rinse cycles, they may also have one or more of the following capabilities: leak testing, cleaning cycle, alcohol rinse, and drying cycle.

Regardless of the AER used, manual cleaning (including thorough rinsing) must be performed prior to placing the flexible endoscope into the AER (even if the AER cleaning cycle is used)Footnote 123 Footnote 124.

Utilization of the AER cleaning cycle provides an extra margin of safety by providing additional cleaning, but it does not replace the absolute requirement for thorough manual cleaning.  Also, even if the AER has leak testing capacity, manual leak testing should still be performed prior to manual cleaning. If an alcohol rinse is not part of the AER cycle, this step needs to be performed prior to manual forced air-drying when the flexible endoscope is going into storage.

Investigations of infections following bronchoscopy have revealed breaches in the reprocessing procedure associated with the AERFootnote 34 Footnote 65. Reports have also identified inconsistencies between the reprocessing instructions provided by the AER manufacturer and the endoscope manufacturer leading to bronchoscopes being inadequately reprocessed when inappropriate channel connectors were usedFootnote 126 Footnote 127. In Canada, awareness of microbial growth in critical components of the AER even when recommended AER maintenance had been followed has further added to the concern over problems with AERs. As a result, the Therapeutic Product Directorate (formerly the Health Product and Food Branch) of Health Canada has issued recommendations for selecting an AERFootnote 124. The criteria listed in Table 6 are also detailed in Part V. Recommendations for Endoscopy and Endoscopy Decontamination Equipment, Section 2.0 (f) i-vii of this guideline.

Table 6: Selection of an Automatic Endoscope ReprocessorFootnote 124

When purchasing an AER, ensure the following criteria are met:

  • the AER is licensed for sale in Canada,
  • there are no potential reservoirs of infection - areas in the AER where water or disinfectant can stagnate,
  • the AER can effectively irrigate all channels of any endoscope to be reprocessed in the AER, ensuring effective contact between the chemical disinfectant and the channel walls,
  • for wash cycles ensure that all wash fluids (water and chemicals) are completely drained and discarded following each wash cycle ensuring that there are no potential reservoirs of infection (areas in the AER where water can stagnate) and reuse of contaminated wash fluid is not possible,
  • for the disinfection cycle, ensure that water and chemicals are completely drained between cycles,
  • if the AER uses a single-use disinfectant ensure that the disinfectant is completely drained and discarded after each cycle,
  • if the AER uses a reusable disinfectant, ensure that the minimum effective concentration (MEC) is monitored daily using test strips available from the supplier of the disinfectant. Discard the disinfectant in accordance with local regulations at the end of the disinfectant's specified reuse life (as specified by the disinfectant supplier) or following a failed MEC test, whichever comes first,
  • the cycle length and temperature can be adjusted to ensure high-level disinfection or sterilization based on the disinfectant/sterilant used,
  • the cycle length can be adjusted to ensure adequate rinsing based on the type of endoscope being reprocessed,
  • the manufacturer of the AER identifies by brand and model each endoscope that may be effectively reprocessed in the AER and the limitations of the AER in reprocessing certain models of endoscopes and accessories (e.g.:  the lumen diameter  of the elevator wire channel in a duodenoscope may not permit adequate fluid flow to effectively reprocess this are of the endoscope).
1.4.5 Reprocessing Endoscopic Accessories

Because of their complex nature, attention and adherence to a validated protocol is critical for reprocessing endoscope accessories.  Accessories such as biopsy forceps, papillotomes, sphincterotomes and cytology brushes may be available as single-use (disposable) or reusable instruments.  All reusable endoscopic accessories that breach mucosal barriers are considered critical and require cleaning with an ultrasonic cleaner followed by sterilization between patientsFootnote 4 Footnote 12 Footnote 14 Footnote 47.  Manufacturer’s guidelines for the care and usage of reusable products must be strictly followedFootnote 11 Footnote 28.

It is important that each institution be fully aware of the issues involved in accessory device selection.  For instance, if reusable accessory devices are used, the institution must have appropriate cleaning equipment (e.g., ultrasonic cleaner) to accommodate proper reprocessing. Contaminated or damaged medical devices pose a potential source for cross-contamination, infection and injury to patients and personnel. In an outbreak of 8 cases of Salmonella newport infection among patients undergoing colonoscopy, the epidemic strain was not recovered from the four colonoscopes used during the outbreak but was recovered from the spiral-wound spring of a pair of biopsy forceps, which are difficult to clean mechanicallyFootnote 58.  Presently the only method that effectively penetrates the metal coils of the spring is steam under pressureFootnote 4 Footnote 101.

Although still controversial, the reuse of critical andsemi-critical single-use devices (SUDs) has been commonplace in many institutions, and undertaken primarily for economic reasonsFootnote 129. The results of a recent survey show that Canadian hospital practices have not changed much in the last decade and that a minority of hospitals reprocess SUDsFootnote 130. In the US, guidelines stipulate that the reprocessing of single-use devices must conform to the same standard as the manufacturer provides.  While there are some third party companies that provide this service, it must be rigorous and controlled. Currently there are no licensed third party reprocessors in CanadaFootnote 2 Footnote 131.

In circumstances where the manufacturer does not approve of reuse, the facility will be legally responsible in establishing when and under what conditions the reuse of medical devices presents no increased risk to patients and that a reasonable standard of care was maintained during reuse of the device.  All institutions that choose to reuse single-use accessory devices need to validate the sterility and integrity of the reprocessed devices, and have in place detailed protocols that include mechanisms for ongoing evaluation and quality assurance monitoring.  This includes the training and retraining of staff, as well as policies and standards to determine the maximum number of uses for the device and to track their usagesFootnote 132 Footnote 133 Footnote 134.  In general, the reuse of single use medical devices is discouraged.

Table 7 - Health Canada RecommendationsFootnote 124

I. Reusable Medical Devices

  • Healthcare facilities and healthcare providers should review instructions provided by the manufacturer prior to the purchase of reusable medical devices to ensure that the device can be adequately reprocessed with available equipment.
  • Healthcare facilities and healthcare providers should require that manufacturers include complete instructions for use, disassembly, cleaning, reassembly and sterilization with all reusable devices, and that they provide appropriate training to users where such training is essential to the safe use of the device.
  • Healthcare facilities and healthcare providers should establish procedures and provide training for staff to ensure that reusable devices are, cleaned, and sterilized according to the manufacturer’s instructions. These instructions should be filed so that they can be easily retrieved and consulted by users.
  • Healthcare facilities and healthcare providers should validate and regularly review their sterilization procedures and ensure that they are being followed.
  • Healthcare facilities and healthcare providers should report to Health Canada any cases in which the manufacturer does not provide adequate instructions for use, cleaning and sterilization of a reusable device.

II. Single-Use Medical Devices

  • Health Canada is concerned that reusing single-use devices may be hazardous to patients. Health Canada is addressing this issue in consultation with the Provinces, Territories, and stakeholders.

1.4.6 Valves and Water Bottles

Outbreaks involving removable parts such as suction valvesFootnote 59 have been reported.  Following each endoscopic procedure, valves must be removed from the endoscope, manually cleaned, and high level disinfected or sterilized according to the manufacturer’s instructions.  It is imperative that all crevices be stringently cleaned so as to be free of debris. The use of an ultrasonic cleaner to enhance soil removal is recommended. Adequate rinsing must be done after sonication to remove any loosened soil. Water bottles and their connecting tubing should be sterilized or, at a minimum, high level disinfected at least daily and sterile water only should be used to fill the bottlesFootnote 1, Footnote 33, Footnote 85, Footnote 135

Note: Each ERCP procedure requires a fresh sterile bottle filled with sterile waterFootnote 1, Footnote 135.

2. Sheathed Endoscopes

One approach that has been proposed to avoid the need for an elaborate reprocessing procedure is to use a sheathed endoscope.  The sheathed endoscope includes a reusable endoscope without channels, and a sterile sheath set comprising a single disposable unit: a sheath; air, water, and suction channels; a distal window; and a cover for the endoscope's control body. All contaminated surfaces, including the channels, are then discarded, thereby eliminating any concern for cross-transmission of infectious agents from the previous patientFootnote 136. There are few studies concerning the use of sheathed instruments for upper and lower endoscopy. In one prospective studyFootnote 137, investigators found that the reprocessing turn-around time of the sheathed instrument was significantly faster (i.e., 9.6 minutes versus 47 minutes) than for a conventional gastroscope. Other studiesFootnote 138, Footnote 139 have reported similar results with reduced instrument turn-around time, but there are concerns about the functional ability of the sheathed endoscopes as well as the cost of the sheath compared to the cost of reprocessing the endoscopeFootnote 140.

3. Storage of Flexible Endoscopes

Flexible endoscopes should be stored in a designated cabinet with a door, in a manner that prevents recontamination or damageFootnote 141.

Storage cabinets should meet the following criteria:

  • made of material that can be disinfected weekly with an approved low-level disinfectant,
  • ventilated when doors are closed,
  • not situated in a procedure room, reprocessing area, or a high traffic area,
  • easily accessible to ensure scopes can be placed inside without damage and without putting the HCW at risk (e.g., HCW must reach a high shelf where endoscope is stored),
  • should accommodate a sufficient number of endoscope to support the patient volume,
  • designed to allow scopes to be stored in the vertical uncoiled position to facilitate drying.

There are storage cabinets available with connections that provide airflow through the endoscope channels, thereby ensuring thorough drying of the channelsFootnote 142. Such special storage cabinets are not necessary if adequate manual drying is achieved prior to storage. If a flexible endoscope is to be stored without being used for more than a week, it must be reprocessed prior to useFootnote 143 Footnote 144 Footnote 145 Footnote 146.

It is critical that the valves are stored separately from the endoscope. They may be placed in a mesh bag and hung on the scope but should not be positioned in the valve port of the endoscope. Storage of endoscopes with the valves in place can trap moisture within the channels and lead to microbial growth and biofilm formation within the channelsFootnote 141.

The carrying case used to transport clean and reprocessed endoscopes outside of the healthcare environment should not be used to store an endoscope or to transport the instrument within the healthcare facility.  An endoscope placed in its transport case will require reprocessing before use on a patient. Should the transport case become contaminated, contact the manufacturer for further instructions. In some instances, the transport case may need to be discardedFootnote 85 Footnote 147.

4. Quality Management

Proper reprocessing of flexible endoscopes is mandatory to ensure safety of patients undergoing pulmonary and GI endoscopy. A quality management program should include the following elementsFootnote 4 Footnote 6 Footnote 101 Footnote 148 Footnote 149:

Staff training

  • The assigned staff must have received sufficient training to safely and properly perform the reprocessing process.  The training should be ongoing and includes hands on training with the specific endoscopes used in the facility and should be documented by the supervising educator. 
  • The introduction of new equipments should be preceded by adequate training of the staff.  An annual recertification program should be considered.
  • The use of written protocols with frequent reminders to staff to not deviate from written instructions.


  • Equipment monitoring including visual inspection to identify conditions that may affect the cleaning or disinfecting process.
  • Maintain a record of each endoscopic procedure, including but not limited to: the type of procedure with date & time, model and serial number of the endoscope used, patient information, staff involved with the procedure, information on the reprocessing method (e.g., AER serial number or identifier, chemical used, staff performing the reprocessing).  This information will facilitate the ability to retrospectively link the scope used for each patient procedure.
  • Annual audits of the reprocessing processes and infection prevention and control practices.
  • A preventative maintenance program should be in place for all medical devices (i.e., endoscopes, AER, leak tester).
  • A surveillance system capable of detecting clusters of infections or pseudo-infections associated with endoscopic procedures.
  • Inform infection prevention and control personnel of any suspected or identified infection.
  • Ensure infection prevention and control personnel are consulted when reviewing, changing or updating the reprocessing procedure or policy.

4.1 Staff Training

The reprocessing of flexible endoscopes has a narrow safety margin due to the complexity of the devices and the processes used.  Deviation from the manufacturer’s recommendations for reprocessing could potentially lead to residual microorganisms being left on the device and thus increase the risk of infectionFootnote 95. The reprocessing of flexible scopes, like all human endeavours, is prone to error as it is a multi-step process relying on both humans and automated or manual cleaning equipment. Inexperienced or untrained staff handling flexible endoscopes during reprocessing increases the likelihood of errors. A major element of quality management is ensuring the provision of device-specific training for endoscopy staff and ongoing competency testing to ensure compliance with protocols. Competent personnel that maintain consistent excellence in practice are crucial to proper cleaning and disinfection of endoscopesFootnote 2 Footnote 3 Footnote 4 Footnote 6 Footnote 7 Footnote 9 Footnote 11 Footnote 16 Footnote 45 Footnote 85 Footnote 91 Footnote 149.

Infection Prevention and Control education is a critical part of the orientation and continuing education for all personnel, including physicians, nurses, and technical staff who work in the endoscopy settingFootnote 6 Footnote 9.  The orientation and continuing education program should include, but not be limited to, the following topics:

  • Mechanisms of disease transmission,
  • Routine Practices and Additional Precautions,
  • The appropriate use of personal protective equipment,
  • Occupational health and safety regulations,
  • Reprocessing procedures for flexible endoscopes and accessories,
  • Safe work practices,
  • Safe handling of chemicals used in reprocessing,
  • Safe waste management.

See Appendix G for sample training protocol.

4.2 Preventative Maintenance and Repair

Periodic assessments of the endoscopes by qualified personnel can reduce both patient risk and repair costs.  Manufacturers will provide trained technical personnel for such assessments and in-house service.  Repairs should always meet or exceed the manufacturer’s original specifications and Original Equipment Manufacturer (OEM) parts should be used. Detecting the need for minor repairs before further damage occurs can prevent use of a substandard endoscope on a patient, and may also prevent unnecessary major repairs and cost.

During the manual cleaning process, trained personnel should inspect devices for functionality and damageFootnote 4, Footnote 11. If an endoscope requires repairs, it is important to ensure proper disinfection; if disinfection is not possible, then handling precautions as specified by the service vendor must be followed when shipping a contaminated endoscope, and according to provincial and federal guidelines for the transportation of dangerous goodsFootnote 11. When an endoscope requires repairs by a party other than the original manufacturer (i.e., third party repairs), the provider of the service should provide information that the new or repaired product meets or exceeds the specifications of the original product (e.g., if the suction channel is changed or repaired, the material used should be physically compatible with the high level disinfectant used).

Repairs must be performed by a party knowledgeable on the various materials used for repairs and on the mechanical complexity of the flexible endoscope being repaired.

4.3 Monitoring Microbial Bioburden in Flexible Endoscope Channels

There are two potential problems that may arise during the reprocessing of flexible endoscopes:  i) persistence of organic material if cleaning is inadequate, and ii) presence of residual microorganisms if high-level disinfection/sterilization are suboptimal or if endoscopes are not dried before storage. The role of ongoing environmental endoscopic surveillance cultures to monitor the effectiveness of routine cleaning and disinfection techniques remains controversial. AustralianFootnote 10, FrenchFootnote 150, and the European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA)Footnote 151 guidelines advocate routine culturing of flexible endoscopes and AER for specific pathogens. North American guidelines, for the most part, do not recommend routine monitoring of endoscope channels unless infection transmission, an outbreak, or a reprocessing error has been identifiedFootnote 3 Footnote 4. Routine bioburden monitoring of flexible endoscope channels may be useful as a “process monitor” by providing a valuable quality assurance tool to help identify previously unknown problems with the reprocessing processFootnote 135, Footnote 136, Footnote 152, Footnote 153, Footnote 154. The results of this monitoring could be used to reinforce staff compliance with proper reprocessing techniques or identify a need to revise reprocessing policies and procedures. Bioburden monitoring should not be used to identify a specific endoscope in need of better reprocessing before use.  Whether patient disclosure is required post-endoscopy if deficiencies in reprocessing are identified through the process monitor is controversial. Appendix D provides an outline of how bioburden testing could be performed as part of an outbreak investigation.

5. Healthcare Worker Protection During Endoscopy/Bronchoscopy and During Equipment Reprocessing

5.1 Hazards During Endoscopy

Endoscopy and bronchoscopy procedures can put both the patient and the healthcare worker (HCW) performing the procedure at risk for infection.  Although transmission of a blood borne pathogen from patient to HCW during endoscopy has not been documented, it is possible. A needlestick or “sharp” injury involving an infected patient represents the greatest risk of transmission of a blood borne pathogen to HCWs.  The probability of  transmission from a needlestick/sharp injury has been estimated at up to 30% for HBV, 4% for HCW, and 0.25% for HIVFootnote 19, Footnote 155.  The likelihood of percutaneous exposure to blood borne pathogens relates primarily to injury with sharp, contaminated endoscopic accessories (e.g., snares, biopsy forceps).  However, the possibility of mucous membrane exposure to contaminated secretions is real if personal protective equipment (PPE) is not wornFootnote 13, Footnote 46.  It is essential that all HCWs working in the endoscopy unit follow Routine Practices to minimize the risk of infection.

Of equal concern is the risk for transmission of tuberculosis (TB) from infected patients who are undergoing bronchoscopyFootnote 72.  Infection prevention and control precautions stipulate staff use of N95 respirators when patients with a potential respiratory infection are undergoing bronchoscopy.

5.2 Hazards During Reprocessing

Reprocessing procedures present the potential risk of biological (e.g., infectious agents) and chemical (e.g., high level disinfectant) exposures. HCW infection can occur during improper handling of patient contaminated instruments, such as the endoscope or accessories after the procedure. Prior to undertaking any cleaning of a flexible endoscope, personnel should put on the appropriate PPE. Reprocessing staff need to recognize that even after the flexible endoscope has been manually cleaned, there may still be viable infectious microorganisms in or on the endoscope (the cleaning process does not disinfect the endoscope) and appropriate use of  PPE is still necessary for handling the endoscope after cleaning.

Cleaning and disinfecting endoscopes involves the use of chemicals that can emit toxic fumes and exacerbate allergies. To avoid danger to staff, patients, and the environment, prudent use as well as established safety precautions are required. Refer to the product label of each product or the MSDS associated with each product for appropriate handling.

5.3 Infection Prevention and Control Practices and Precautions

The most important ways to prevent acquiring an infection are to perform good hand hygiene and wear the appropriate PPE.  In addition, proper removal of PPE after the procedure is essential, as the PPE itself can be a source of infection.  All personnel involved in the endoscopic procedure and/or reprocessing the endoscope after use require education in the basic principles of 'Routine Practices'Footnote 13 and 'Hand Hygiene'Footnote 12.  Hand hygiene should be performed before and after every contact with a patient and his/her  surroundingsFootnote 12, Footnote 156.  Gloves and a fluid resistant gown should be worn during an endoscopic procedure and while cleaning endoscopes.  Gowns should be changed between patient procedures, after cleaning instruments, and/ or when they are dirtyFootnote 157.  Although rare, there have been case reports of HCV transmission from a blood splash to the conjunctiva of HCWsFootnote 158, Footnote 159, as has a case of bacterial conjunctivitis following a splash during colonoscopyFootnote 73. Therefore, facial protection (i.e., mask and eye protection/face shield) should be worn to protect the mucous membranes of the eyes, nose and mouth during all endoscopic procedures and while reprocessing instruments. Eyeglasses are not sufficient to protect from splashes. For endoscopy procedures, in general, a surgical/procedure mask will suffice. If an infection is suspected a NIOSH certified N95 respirator should be worn during bronchoscopyFootnote 160, Footnote 161, Footnote 162, Footnote 163PPE should not be worn outside the room in which the procedure takes place or outside the room in which the instruments are cleaned.

5.4 Occupational Health and Safety Considerations

Healthcare workers working in environments where endoscopes are handled should receive all vaccines as recommended by the National Advisory Committee on ImmunizationFootnote 164 including the hepatitis B vaccine. HCWs should also have regular tuberculin skin tests (TST), as per Health Canada: Guidelines for preventing the transmission of tuberculosis in Canadian health care facilities and other institutional settingsFootnote 165. The frequency of TST will depend on the burden of patients with TB actually seen in the clinic (e.g., annually or every 6 months for high risk facilities)Footnote 165.  In the event of an exposure to a patient with infectious TB, the hospital’s protocol for post exposure management should be followed.  Similarly, if there is a percutaneous or mucous membrane exposure to blood or body fluids during the procedure, follow-up through Occupational Health and Safety is required.

Exposure to glutaraldehyde can cause headaches, conjunctivitis, dermatitis, asthma-like responses and nasal irritationFootnote 21.  This can be minimized with appropriate point-of-use ventilation in accordance with the MSDS for the product usedFootnote 11.  Less toxic high level disinfectants (e.g., 0.55% ortho-phthalaldehyde) are now available, but no option is idealFootnote 166. While cleaning endoscopes, to protect against contact with chemicals that can cause caustic injuries, personnel should wear gloves, facial protection (i.e., mask and eye protection/face shield) to protect the eyes, mucous membranes and face from splashes, and moisture-resistant gowns or aprons that protect the bodyFootnote 157. All chemicals must be stored and handled appropriately and all personnel who handle chemicals need to be aware of the hazards associated with the materials and how to manage spills. Refer to the product label of each product, or the MSDS associated with each product for appropriate handling.

5.5 Environmental Controls

Certain microorganisms are transmissible by the airborne route (e.g., TB), and thus environmental controls are required. A negative pressure room is required for all bronchoscopy procedures and in the area where the patient is recovering from the procedureFootnote 165, Footnote 167.  A minimum total air exchange rate of 12 per hour is recommended for newly constructed bronchoscopy suites with 6 exchanges per hour for existing facilities. The direction of air should be inward (negative pressure) and the air should be exhausted to the outdoors through a dedicated system or HEPA filteredFootnote 9, Footnote 167, Footnote 168, Footnote 169. The endoscopic instrument reprocessing room should be under negative pressure and requires an air exchange rate of, at minimum, 8 per hour to protect personnel from toxic vapours generated by cleaning or disinfecting agents, and covered containers should be used for additional control of vapoursFootnote 167, Footnote 170.

Work areas need to be properly ventilated to ensure product levels are below threshold limit values (TLVs) specified in provincial OH&S regulations.  Recirculation of air in the area where the product is used is prohibited by OH&S regulation and ventilation must be to the exterior. Use of an AER helps to reduce vapour concentration and the risk from splashes.

Ethylene oxide (ETO) is a designated substance under the Canadian Environmental Protection Act. Healthcare facilities that use 10 kg. or more of ETO per year for sterilization must comply with Environment Canada: Guidelines for the Reduction of Ethylene Oxide Releases from Sterilization ApplicationsFootnote 121 and  Canadian Standards Association Z314.9-01: Installation, Ventilation, and Safe Use of Ethylene Oxide Sterilizers in Health Care FacilitiesFootnote 114.

6. Endoscopy Unit Design

The design of an endoscopy unit is important to facilitate proper infection prevention and control and occupational health and safety. Major considerations in design and use of space for patient procedures, equipment reprocessing and storage include: i) patient volume, ii) traffic flow, and iii) types of endoscopic procedures performedFootnote 4. The main objective is to create an efficient flow of patients and personnel through the unit, from reception to procedure and then to recovery, while maintaining a distinct separation between patient care areas and contaminated space and equipment.  Providing comfortable working conditions for clinical staff, as well as supportpersonnel, will promote an environment where proper procedures are routinely exercised.  An ideal endoscopy unit would permit a one-way or circular flow for patients and endoscopes. 

In procedure rooms, the workflow should be from clean to dirty. A dedicated clean area should be provided for charting, dictation and supplies. A separate soiled holding area must be provided for pre-cleaning of scopes and handling of contaminated instruments. The procedure room should have a separate dedicated hand washing sink with hands-free controls. 

An appropriate airborne precautions environment should be available for patients with confirmed or suspected infectious airborne diseases if they cannot be immediately transported to an appropriately ventilated roomFootnote 13, Footnote 166.

In designing an endoscopy unit, consideration should be given to providing patients with private bathroom and change room. A staff lounge should be made available as eating, drinking, personal hygiene (e.g., cosmetic application, contact lenses) activities should be prohibited from all patient care areas and the reprocessing roomFootnote 4, Footnote 171.

Instrument reprocessing space should be physically separate from patient procedure rooms, maintained as a restricted access area, and enable personnel to respect the one-way work-flowFootnote 11, Footnote 67. Reprocessing functions can be broken down into 3 general areas: cleaning, decontamination, and storage.  The workflow should be unidirectional from the contaminated or ‘dirty’ area to the clean assembly area and then to storage. Adequate space should be provided for each function with dedicated storage space in a separate roomFootnote 167. Reprocessing areas should have dedicated plumbing and drainsFootnote 11, and if AERs are used, the area should be designed with adequate space and utility connections specific to the machine being usedFootnote 4, Footnote 167.  Adequate space for storage of chemical disinfectants should be considered near the AER.  Other considerations for an endoscope reprocessing area include monolithic or joint free flooringFootnote 167, Footnote 168 and stainless steel counters.  Sinks should have rounded edges and enough depth to facilitate complete immersion of the endoscope.  The size of the sink should be adequate to ensure the endoscope can be positioned without tight coiling as this could damage the fiberoptic bundles. Any other design features that promote easy cleanup are desirable. Hands-free doors and sinks will improve workflow and reduce risk of cross contamination. Separate, dedicated hand washing sinks must be at each entrance or exit.

Appropriate ventilation (see Section 5.5) must be provided to remove toxic vapours of disinfection chemicals and to handle any aerosolized particles or microbes. The manual cleaning and disinfection space should be under negative pressure in relation to the adjoining rooms, whereas the endoscope storage space should be under positive pressureFootnote 170. Ventilation in the storage area should be adequate to ensure dry storage of clean endoscopes.

7. Surveillance and Outbreak Investigation and Management

Few healthcare settings have routine post-procedure surveillance programs in place to monitor the incidence of endoscopy-associated infections.  Many endoscopies are now carried out in outpatient clinics and follow-up of patients in the community is difficult. In addition, some infections, such as hepatitis B and tuberculosis, have long incubation periods, and thus clinical infection developing later may not be linked to an earlier endoscopy. It has been suggested that infection surveillance programs be implemented, at least periodically, for high risk procedures such as Endoscopic Retrograde Cholangiopancreatography (ERCP)Footnote 45.

An outbreak is defined as an increase in the rate of infection or disease above the usual. This requires that ongoing surveillance for potential complications be in place so that the background rate is known or can be calculated, or alternatively that a retrospective review could be performed to obtain baseline data.  There have been numerous reported outbreaks of infection related to endoscopic procedures (See Table 1) as well as transmission of microorganisms without disease related to contaminated endoscopes (See Table 2).

Any occurrence of infection after an endoscopy procedure should be reviewed since it might be a sentinel event that signals the occurrence of an outbreak. If an outbreak is suspected, an investigation should be initiatedFootnote 4, Footnote 172. Appendix H outlines steps to be taken during an outbreak investigation. Many of these steps may be performed concurrently.

8. Investigation of a Reprocessing Problem

Potential exposure events due to breaches of disinfection and sterilization guidelinesFootnote 57, Footnote 173, and failures in the disinfection or sterilization processesFootnote 25 are not uncommon in healthcare settings.  The purpose of investigating a potential reprocessing problem is to discover the factor(s) that led to the potential exposure and to protect patients from adverse events, and not to assign blame to a particular person or persons.

Any investigation should be undertaken using a standardized approach. Rutala et al.Footnote 174 have described a process for exposure investigation after potential failure of a disinfection/sterilization procedure. Table 8 outlines steps to be taken to investigate a reprocessing problem. Every situation is unique, therefore steps taken in the investigation should be adapted to the specific situation. In addition, the American Society for Gastrointestinal Endoscopy (ASGE) has recently published guidelines for patient notification and follow-up when a significant breach in reprocessing has been discoveredFootnote 175.

Table 8. Investigation of a Reprocessing Problem

  1. Confirm disinfection or sterilization reprocessing failure (e.g., review time and date of possible failure, sterilization method used, process parameters, and physical, chemical, biological indicators).
  2. Impound any improperly disinfected/sterilized items.
  3. Do not use the questionable disinfection/sterilization unit (e.g., sterilizer, AER) until proper functioning can be assured.
  4. Inform key personnel (e.g., medical and nursing director of involved unit, risk management).
  5. Conduct a thorough evaluation of the cause of the disinfection/sterilization failure (e.g., review exact circumstances of failure: dates and results of process measures, physical, chemical, biological indicators).
  6. Prepare a line listing of potentially exposed patients (e.g., name, identification number), date of exposure, contaminated device used, underlying risk factors for infection, development of any healthcare-associated infections, or other adverse events.
  7. Assess whether disinfection/sterilization failure increases patient risk for infection.
  8. Inform expanded list of personnel of the reprocessing issue (e.g., administration, public relations, legal department).
  9. Develop a hypothesis for the disinfection/sterilization failure and initiate corrective action.
  10. Develop a method to assess potential adverse patient events (e.g., laboratory tests for source patients and exposed persons to blood borne pathogens).
  11. Consider notification of provincial and federal authorities.
  12. Consider patient notification.
  13. Develop long term follow-up plan (e.g., long-term surveillance, changes in current policies and procedures).
  14. Prepare after action report.

Adapted from RutalaFootnote 174

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