Indian Journal of Medical Microbiology Medknow Publications on behalf of Indian Association of Medical Microbiology ISSN: 0255-0857 EISSN: 1998-3646 Vol. 25, Num. 4, 2007, pp. 429-431

Indian Journal of Medical Microbiology, Vol. 25, No. 4, October-December, 2007, pp. 429-431

Correspondence

Endoscope reprocessing: Stand up and take notice!

Das A, Ray P, Sharma M

Department of Medical Microbiology, PGIMER, Chandigarh - 160 012

Correspondence Address: Department of Medical Microbiology, PGIMER, Chandigarh - 160 012, India. Email: das_anindita73@yahoo.co.in.

Date of Submission: 02-May-2007
Date of Acceptance: 03-May-2007

Code Number: mb07123

Dear Editor,

Endoscopy is a very frequently performed diagnostic and therapeutic interventional modality. Recently, it has been reported that up to 270,000 infections (in 2.7% of procedures) are transmitted annually by flexible endoscopes in the USA. ^[1] There have been> 500 reports of infections due to use of contaminated endoscopes, commonly by Pseudomonas aeruginosa , Salmonella spp., Mycobacterium tuberculosis and atypical mycobacteria. Recommendations for reprocessing of endoscopes have been established worldwide, but lack of compliance is rampant in 20-70% of centres in Europe, Australia and Asia. ^[2],[3] Compliance is also very poor in Japan, India (only 1/3 of 133 centres practiced minimum disinfection), Western Europe (inadequate disinfection in ≥30% centres) and USA (inadequate disinfection of 23.9% of endoscopes). ^[4]

International recommendations for endoscope reprocessing is a stepwise process; pre-cleaning, leak testing, cleaning, rinsing, high level disinfection (HLD)/sterilization, rinsing, drying and storage. Cleaning is extremely important, resulting in 2-6 log ₁₀ (mean 3 log ₁₀ ) reduction in bacterial load and almost complete removal of viruses. Cleaning should be done with mildly alkaline/neutral enzyme cleaners and household detergents. Those containing aldehydes should not be used. The most widely used disinfectants are: glutaraldehyde (GA) orthophthalaldehyde (OPA), hydrogen peroxide (H ₂O₂ ) and per acetic acid (PAA). Although use of GA is banned in a few European countries (skin and respiratory irritant), it is still frequently used worldwide. Several newer disinfectants are available and material compatibility and efficacy should be validated before use [Table - 1]. OPA requires lesser time for HLD (12 min at 20 °C), does not require activation, has better mycobactericidal activity than GA, but is costlier. PAA is a better biocide, less irritant and has ability to remove hardened material, but is corrosive and less stable. Endoscope and valves should be immersed in a high-level disinfectant or liquid chemical sterilant (LCS) solution with good material compatibility; all channels should be irrigated; and manufacturer′s recommendation for the pH, temperature and time of exposure to the disinfectant/LCS followed. The concentration of disinfectant solution should be tested at least daily. Final rinsing should be done under running sterile water. Drying should be done between patients by pressurized air (1.4 atm) and before storage, using 70% alcohol flush, followed by pressurized air. The endoscope should be disassembled in a well-ventilated storage cupboard. Accessories that penetrate the mucosal barrier should be single use or cleaned and then sterilized between each patient use. The automatic flexible endoscope reprocessor (AFER) should be operated by trained personnel. Manual cleaning of the endoscope is necessary prior to AFER use. Endoscope reprocessors need to be regularly cleaned to prevent formation of biofilms. Strict microbiological monitoring is essential. Regular cultures are recommended in several countries for quality assurance, but in the United States, sampling is advised if clustering of infections following endoscopy is suspected. ^[5]

The practical problem of handling patient load with lesser number of endoscopes and hence shorter time period to practice reprocessing, can be frustrating. The cost of maintaining AFER, multiple endoscopes, newer/powerful disinfectants, enzymic cleaners, sterile water for rinsing may not be financially sustainable in the government sector and small private endeavours, which provide health care to the majority of the Indian population. Trained nursing and technical staff for manual/automated reprocessing are also not easily available.

In our institute, endoscope reprocessing is done once by an AFER at the end of the day and the nursing personnel have been trained by the manufacturers in its use. Reprocessing between patients is done just by immersing in GA (as per manufacturer′s instructions) and drying of the endoscopes between patients is not always followed. PGIMER, Chandigarh has an infection control committee with requisite infection control guidelines and an ongoing education and training programme (infection control practices, sterilization/disinfection in CSSD, operating room nurses) for all health care personnel. There is no established consensus or awareness about the requirement for microbiological monitoring and quality assurance during AFER use.

Use of 2.5% GA for 5 min at 35 °C [Table - 1] can be cost-effective, since this temperature is easily achieved in our climate and the duration is shortened by 75%. The usual practice of simply rinsing the endoscopes and immersing in 2% GA for 20 min is ineffective. Thorough cleaning to remove organic matter is essential; therefore, shortening the disinfection time and utilizing the left-over time for manual cleaning, rinsing and drying between patients is a reasonable option. Rinsing may be done with filtered or sterile water, but not tap water. Detergent solution should be renewed each time and disinfectant concentration should be checked daily with test strips. It is important to remember that use of AFERs does not circumvent manual cleaning. Microbiologists and physicians need to formulate local guidelines for environmental sampling, frequency of monitoring, interpretation of positive cultures and possible remedial action, which are customized according to the patient load and set-up. The common practice of performing endoscopy on infectious patients at the end of the day will not eliminate the risk of encountering patients with latent or sub-clinical infections. Regular CMEs, training programmes and lectures should be conducted by societies (e.g., IAMM, HISI) for doctors, nurses and technicians for increasing awareness.

References

Copyright 2007 - Indian Journal of Medical Microbiology

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