Colonoscopy is a well recognized diagnostic and therapeutic tool. Endoscope reprocessing must be done correctly every time; a breach of protocol leading to transmission of infection has the potential to bring endoscopy to a halt. Standards exist that guide the practitioner in all health care settings to minimize the chance of transmission of infection. Safe injection practices and reprocessing of endoscopes using high-level disinfection and sterilization methods may help avert the risk of contracting possible infections during colonoscopy procedures.
Maximizing the value of colonoscopy begins with assuring that the procedure is as safe as possible. In the United States alone, more than 10 million colonoscopic procedures are estimated to be performed annually. Colonoscopy is a well-recognized diagnostic and therapeutic tool; complications are rare. Maintenance of effective infection-control processes is a key component of safety, and proper reprocessing of endoscopic equipment is a critical part of any procedure. Meticulous attention to detail during the reprocessing of flexible endoscopic instruments is crucial. Effective cleaning and disinfection of the endoscope is an integral part of the procedure.
Endoscope reprocessing must be done correctly every time; a breach of protocol leading to transmission of infection has the potential to bring the field of endoscopy to a halt. Standards concerning infection control in endoscopy have been developed and disseminated widely since the late 1980s, helping to ensure continued safety in gastrointestinal (GI) endoscopy. Physicians and associates working in settings where colonoscopy is performed need to be vigilant about strict adherence to all infection-control and reprocessing guidelines.
Potential infection risks during colonoscopy
Standards exist that guide the practitioners in all health care settings to minimizing the chance of transmission of infection. The potential for transmitting infection during colonoscopy exists when there is a breakdown in adherence to such standards. In general, the key issues in reducing the risk of transmission of infection during colonoscopy center on adhering to “best practices” in terms of:
- 1.
General infection-control principles
- 2.
Safe injection practices
- 3.
Endoscope reprocessing.
General Infection-Control Principles
Recommended practices for the prevention of transmission of infection in health care settings are available in guidelines that have been promulgated and widely disseminated. The latest Centers for Disease Control and Prevention (CDC) guidelines were published in 2007, and is a comprehensive review that should be part of the standard operating practices for any facility where colonoscopy is performed.
Personal protective equipment such as gowns, gloves, eye protection, and respiratory protective devices should be easily available and used regularly as appropriate to protect endoscopy personnel from exposure to blood, chemicals, and other potentially hazardous materials.
Both the CDC and the Occupational Safety and Health Administration (OSHA) require the use of gloves when touching blood or other potentially infectious materials. The CDC recommends the use of masks and eye protection (or a face shield) during patient care activities that are “likely to generate splashes or sprays of blood, body fluids, secretions and excretions.” OSHA recommends the use of such equipment whenever “splashes, spray, splatter or droplets of other infectious materials may be generated and eye, nose or mouth contamination can be reasonably anticipated.” Thus, recommendations for the use of eye protection and a mask or a face shield allow some discretion and may be subject to interpretation. Both CDC and OSHA recommend the use of protective aprons or gowns when appropriate.
Hand washing should occur after contact with any potentially infectious or contaminated items. The CDC recommends that hands should be washed immediately after gloves are removed, after contact between patients, and in some situations, during examination of the same patient to prevent cross-contamination of different sites.
Safe Injection Practices
Safe injection practices are part of high-quality medical care in all settings, including sites where colonoscopy is performed. Several outbreaks of hepatitis C virus infection have occurred in endoscopy centers, ultimately traced to improper injection practices. Improper use of single and multidose anesthetic vials, reuse of needles and syringes, and improper use of intravenous tubing and connectors have all been implicated for spreading infection. In a well-publicized case in Las Vegas, Nevada, in 2008, at least 6 people developed acute hepatitis C. In this situation, cross-contamination between patients occurred after syringes that were reused to draw additional doses of anesthetic from single-use vials were then subsequently used for other patients undergoing endoscopy. CDC guidelines relevant to safe injection practices during endoscopy include the following :
- •
Use aseptic technique
- •
Do not administer medications from a syringe to multiple patients, even if the needle or the cannula on the syringe is changed
- •
Use fluid infusion sets for one patient only
- •
Use single-dose vials whenever possible
- •
Do not administer medications from single-dose vials to multiple patients
- •
If multidose vials must be used, both the needle or cannula and syringe used to access the multidose vial must be sterile
- •
Do not keep multidose vials in immediate patient treatment areas.
The need to maintain safe injection practices and be vigilant over the injection practices of all staff working in endoscopy cannot be overemphasized.
Endoscope Reprocessing
Guidelines for reprocessing endoscopes, when followed meticulously, prevent any transmission of infection from one patient to the next. Similarly, reprocessing guidelines for other items used during GI endoscopy (accessories, general medical equipment) are specified by the manufacturer and must be followed meticulously. All items used in GI endoscopy must be reprocessed according to guidelines and manufacturer’s instructions to prevent cross-contamination.
Mechanism of transmission and level of risk
Transmission of infection at the time of GI endoscopy is exceedingly rare. When reviewed critically, most cases of infection deemed related to an endoscopic procedure can be traced to the failure to adhere to published guidelines for reprocessing. Mechanisms of transmission can be further divided into these broad areas:
- 1.
Procedural errors in the meticulous cleaning and disinfection of the endoscope, leading to retained microorganisms on the endoscope. These organisms may accumulate in the crevices and joints of the instruments.
- 2.
Insufficient exposure time to liquid chemical germicides (LCGs) or use of inappropriate disinfectant solutions.
- 3.
Improper use of automated endoscope reprocessing equipment.
- 4.
Contaminated water bottles and irrigating solutions.
- 5.
Inadequate drying and improper storage of endoscopes after reprocessing.
The reported frequency of transmission of infection in GI endoscopy has been estimated to be 1 in 1.8 million. This much-quoted rate emanates from Spach and colleagues in 1993, who reviewed 281 infections related to GI endoscopy, as well as 96 thought to have been caused by bronchoscopy ( Table 1 ). Of the 281, all but 28 occurred before 1988, the year when importance of adequate manual cleaning as well as disinfection were stressed in guidelines published by the American Society for Gastrointestinal Endoscopy (ASGE) and the British Society of Gastroenterology (BSG). The ASGE Technology Committee reviewed Spach’s data in 1993 and then estimated that 40 million GI procedures had been done in the United States between 1988 and 1992. This meant there had been 28 reported infections in approximately 40 million endoscopic procedures, for an estimated rate of transmission of infection by GI endoscopy of 1 in 1.8 million. Some think that with widespread adoption of the Multi-Society Guidelines in 2003 the actual transmission rate of infection via endoscopy is considerably lower, with estimates in the 1 in 6 million range.
| Infection (I) or Contamination (C) | Cleaning Procedure | Disinfection Process | Rinsing Process | Automated Processor | Contaminated Processing or WaterBottle | |
|---|---|---|---|---|---|---|
| Before Guidelines | ||||||
| A. Gram-negative bacilli | ||||||
| Pseudomonas aeruginosa | I | X | X | X | X | X |
| Klebsiella sp | I | X | X | |||
| Enterobacter sp | I | X | X | |||
| Serratia marcescens | I | X | X | |||
| Salmonella sp including S typhi | I | X | X | X | ||
| Helicobacter pylori | I | X | X | X | ||
| Bacillus sp | C | X | X | |||
| Proteus sp | C | X | X | |||
| B. Mycobacteria | ||||||
| Mycobacterium tuberculosis | I | X | X | |||
| Atypical mycobacteria | I | X | X | |||
| C. Fungi | ||||||
| Trichosporon sp | C | X | X | X | ||
| Rhodotorula rubra | C | X | X | X | ||
| D. Parasites | ||||||
| Strongyloides | I | X | X | |||
| E. Viruses | ||||||
| Hepatitis B | I | X | X | |||
| After Guidelines | ||||||
| A. Gram-negative bacilli | ||||||
| P aeruginosa | I | X | X | X | ||
| B. Mycobacteria | ||||||
| M tuberculosis | I | X | X | X | X | |
| Atypical mycobacteria | C | X | ||||
| C. Viruses | ||||||
| Hepatitis C | I | X | X | X | ||
However, it is also possible that the reported infection rate is underestimated because of factors such as inadequate surveillance, asymptomatic infections, and infections with long incubation periods. Some investigators have suggested that endoscopists do not capture all their complications because follow-up is too short; infectious complications might not be recognized to be related to the procedure, or the patient may return to another caregiver or facility and the complication is never apparent to the health care provider who completed the procedure. These investigators recommended a 30-day follow-up of GI procedures (as opposed to the traditional assessment of complications recognized during and immediately after the procedure) as a better measure to study endoscopic complications.
Every patient must be considered as a potential source of infection, and all endoscopes must be reprocessed in a standardized fashion. It is crucial to understand that all recent cases of pathogen transmission related to endoscopy have been the result of a breach in following accepted protocols. Reprocessing standards are published, updated, and widely available, and include the Multi-Society Guidelines (2003), as well as individual guidelines from the ASGE (2008), Society for Gastrointestinal Nurses and Associates (SGNA) (2008), European Society for Gastrointestinal Endoscopy (2008), Association of Perioperative Registered Nurses (AORN) (2002), and BSG (1998).
Mechanism of transmission and level of risk
Transmission of infection at the time of GI endoscopy is exceedingly rare. When reviewed critically, most cases of infection deemed related to an endoscopic procedure can be traced to the failure to adhere to published guidelines for reprocessing. Mechanisms of transmission can be further divided into these broad areas:
- 1.
Procedural errors in the meticulous cleaning and disinfection of the endoscope, leading to retained microorganisms on the endoscope. These organisms may accumulate in the crevices and joints of the instruments.
- 2.
Insufficient exposure time to liquid chemical germicides (LCGs) or use of inappropriate disinfectant solutions.
- 3.
Improper use of automated endoscope reprocessing equipment.
- 4.
Contaminated water bottles and irrigating solutions.
- 5.
Inadequate drying and improper storage of endoscopes after reprocessing.
The reported frequency of transmission of infection in GI endoscopy has been estimated to be 1 in 1.8 million. This much-quoted rate emanates from Spach and colleagues in 1993, who reviewed 281 infections related to GI endoscopy, as well as 96 thought to have been caused by bronchoscopy ( Table 1 ). Of the 281, all but 28 occurred before 1988, the year when importance of adequate manual cleaning as well as disinfection were stressed in guidelines published by the American Society for Gastrointestinal Endoscopy (ASGE) and the British Society of Gastroenterology (BSG). The ASGE Technology Committee reviewed Spach’s data in 1993 and then estimated that 40 million GI procedures had been done in the United States between 1988 and 1992. This meant there had been 28 reported infections in approximately 40 million endoscopic procedures, for an estimated rate of transmission of infection by GI endoscopy of 1 in 1.8 million. Some think that with widespread adoption of the Multi-Society Guidelines in 2003 the actual transmission rate of infection via endoscopy is considerably lower, with estimates in the 1 in 6 million range.
| Infection (I) or Contamination (C) | Cleaning Procedure | Disinfection Process | Rinsing Process | Automated Processor | Contaminated Processing or WaterBottle | |
|---|---|---|---|---|---|---|
| Before Guidelines | ||||||
| A. Gram-negative bacilli | ||||||
| Pseudomonas aeruginosa | I | X | X | X | X | X |
| Klebsiella sp | I | X | X | |||
| Enterobacter sp | I | X | X | |||
| Serratia marcescens | I | X | X | |||
| Salmonella sp including S typhi | I | X | X | X | ||
| Helicobacter pylori | I | X | X | X | ||
| Bacillus sp | C | X | X | |||
| Proteus sp | C | X | X | |||
| B. Mycobacteria | ||||||
| Mycobacterium tuberculosis | I | X | X | |||
| Atypical mycobacteria | I | X | X | |||
| C. Fungi | ||||||
| Trichosporon sp | C | X | X | X | ||
| Rhodotorula rubra | C | X | X | X | ||
| D. Parasites | ||||||
| Strongyloides | I | X | X | |||
| E. Viruses | ||||||
| Hepatitis B | I | X | X | |||
| After Guidelines | ||||||
| A. Gram-negative bacilli | ||||||
| P aeruginosa | I | X | X | X | ||
| B. Mycobacteria | ||||||
| M tuberculosis | I | X | X | X | X | |
| Atypical mycobacteria | C | X | ||||
| C. Viruses | ||||||
| Hepatitis C | I | X | X | X | ||
Related posts:
Sedation Issues in Quality Colonoscopy
Complications of Colonoscopy: Magnitude and Management
Maximizing the Value of the Endoscopist–Pathologist Partnership in the Management of Colorectal Polyps and Carcinoma
Advanced Systems to Assess Colonoscopy
The Use of Databases and Registries to Enhance Colonoscopy Quality
Defining an Episode of Care for Colonoscopy: Work of the High Value Health Care Project Characterizing Episodes and Costs of Care
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