消化内镜清洗消毒的研究

为选择方便、实用、可靠的清洗消毒方法和高效、广谱、无毒付作用的内镜消毒剂。在近１５万例次内镜检查、治疗的同时，对内镜的清洗、消毒进行了一系列研究。内镜使用后，先对镜身及孔道附着物彻底清除，再用三步法对内镜清洗、消毒，基本达到灭菌目的。手工操作应强调规范、到位，机械自动洗消可减轻劳动强度，并可避免人为因素影响消毒效果。常用消毒剂新洁尔灭、戊二醛等，能有效杀灭常见微生物，但有一定的毒付作用。酸化电位水具有高氧化还原电位、低ｐＨ值和氧化能力，是一种高效、迅速、安全、方便的消毒制剂。     

Reprocessing of flexible endoscopes and endoscopic accessories - an international comparison of guidelines

Endoscopic examinations and procedures are essential for diagnosis and treatment of gastrointestinal diseases. As a result of poor reprocessing practice microorganisms can be transmitted via endoscope. The majority of infection transmissions is due to insufficient performance of cleaning and disinfection disregarding guidelines of societies of gastrointestinal endoscopy. A review of the literature and a comparison of European and American guidelines for reprocessing flexible endoscopes are given. Differences in the classification of endoscopic devices, on the possibility of prion transmission, recommendations on staff training and protection, quality assurance of reprocessing and evidence-based graduation of guidelines are stressed and discussed. With respect to the procedure of endoscope reprocessing, differences concerning the cleaning solution to choose, necessity of thoroughly manual cleaning and brushing of the accessible endoscope channels (even in the case of subsequent automatic reprocessing endoscopes in washers-disinfectors), disinfection solution, microbiological quality of water for final rinsing and rationale for alcohol flush of endoscope channels for better drying are mentioned. The need for experimental investigations of the cleaning and disinfection process is stressed. In contrast to recent guidelines of European and American societies of gastrointestinal endoscopy, the now updated recommendations of the Robert Koch-Institute for reprocessing flexible endoscopes and endoscopic accessories are evidence-based and graduated.     

Disinfection and endoscopy: Summary and recommendations

This working party was convened by the organizers of the World Congresses of Gastroenterology, Sydney 1990. Its remit was to produce a report on disinfection in endoscopy. Endoscopy plays an essential role in the management of gastrointestinal disorders; its benefits far outweigh the occasional complications which arise. Nevertheless, case reports and surveys performed over a 20-year period confirm that endoscopic procedures do occasionally cause cross-infection and the current epidemic with human immunodeficiency virus (HIV) has highlighted the potential for more serious disease transmission if suitable precautionary measures are not generally applied in endoscopy practice. Contaminated equipment may cause infection in three ways: transmission of pathogenic organisms from one patient to another, the commonest example being Salmonellosis; transmission of infection such as hepatitis B (HBV) from patient to staff by needle-stick injury; and introduction of opportunistic organisms which colonize endoscopic and ancillary equipment on storage. This may cause focal sepsis or septicaemia, particularly in the immunocompromised, or cholangitis and pancreatic sepsis following endoscopic retrograde cholangiopancreatography (ERCP). These risks can be eliminated by the use of effective cleaning and disinfection techniques, by providing suitable staff training and by paying attention to endoscopy room procedures. Both HBV and HIV are inactivated by all currently accepted disinfecting or sterilizing procedures.(ABSTRACT TRUNCATED AT 250 WORDS)     

Disinfection of endoscopic equipment

Patients undergoing endoscopy are at risk of infection from the use of contaminated equipment. Dangers arise from the transmission of organisms from one patient to another and from the introduction of opportunist organisms which colonize endoscopic equipment on storage and can lead to sepsis and death in those who are immunocompromised and at ERCP. Staff are in danger from needle-stick injury and sensitivity to aldehyde disinfectants. These risks can be eliminated by careful attention to disinfection techniques. The most important part of endoscope disinfection is thorough mechanical cleaning first, followed by 5-10 min total immersion of the instrument and all channels in 2% glutaraldehyde (or the equivalent). At the end of the endoscopy list, following the disinfection protocol, all equipment should be dried internally and externally prior to storage. Staff must be fully aware of the risks of infection in endoscopy, be protected from hepatitis B by vaccination, and be fully trained in disinfection techniques. Glutaraldehyde should be used only in closed systems or in well-ventilated areas with the operator protected from direct contact from splashing and fumes. Institutions should designate an individual to be responsible for preparing, monitoring and overseeing disinfection procedures within the endoscopy room and for ensuring that regular microbiological testing of equipment (including automatic disinfecting machines) is undertaken.     

Bacteriologic testing of endoscopes after high-level disinfection

BACKGROUND: There are no definitive data available concerning microbiologic safety of prolonged endoscope storage after reprocessing and disinfection. This study evaluated the durability of high-level disinfection of endoscopes stored in a dust-proof cabinet for 5 days. METHODS: Three different types of endoscopes (upper endoscopes, duodenoscopes, colonoscopes) were tested. After completion of the endoscopic procedure, endoscopes were subjected to an initial decontamination, followed by manual cleaning with the endoscope immersed in detergent. The endoscopes then were placed in an automatic reprocessor that provides high-level disinfection. They then were stored by hanging in a dust-proof cabinet. Bacteriologic samples were obtained from the surface of the endoscopes, the openings for the piston valves, and the accessory channel daily for 5 days, and by flush-through (combined with brushing) from the accessory channels after 5 days of storage. Samples were cultured for all types of aerobic and anaerobic bacteria, including bacterial spores, and for Candida species. RESULTS: For all assays, all endoscopes were bacteria-free immediately after high-level disinfection. Only 4 assays (of 135) were positive during the subsequent 5-day assessment (skin bacteria cultured from endoscope surfaces). All flush-through samples were sterile. CONCLUSIONS: When endoscope reprocessing guidelines are strictly observed and endoscopes are stored in appropriate cabinets for up to 5 days, reprocessing before use may not be necessary.     

Australian infection control in endoscopy consensus statements on carbapenemase‐producing Enterobacteriaceae

Outbreaks of carbapenemase‐producing Enterobacteriaceae clinical infections related to endoscopic transmission are well documented. The high morbidity and mortality associated with these infections emphasizes the need to reassess endoscopic reprocessing protocols. The Gastroenterological Society of Australia established a multi‐society committee to formulate evidence‐based consensus statements on the prevention and management of endoscopic transmission of carbapenemase‐producing Enterobacteriaceae. A literature search was undertaken utilizing the MEDLINE database. Further references were sourced from published paper bibliographies. Nine statements were formulated. Using the Delphi methodology, the statements were initially reviewed electronically by the committee members and subsequently at a face‐to‐face meeting in Melbourne, Australia. After further discussion, four additional sub‐statements were added resulting in a total of 13 statements. Each statement was assessed for level of evidence, recommendation grade and the voting on recommendation was recorded. For a statement to be accepted, five out of six committee members had to “accept completely” or “accept with some reservation.” All 13 statements achieved consensus agreement. Eleven statements achieved 100% “accepted completely.” Two statements were 83% “accepted completely” and 17% “accepted with some reservation.” Of particular significance, automated flexible endoscope reprocessors were mandated for high‐level disinfection, and the use of forced‐air drying cabinets was mandated for endoscope storage. These evidence‐based statements encourage preventative strategies with the aim of ensuring the highest possible standards in flexible endoscope reprocessing thereby optimizing patient safety. They must be considered in addition to the broader published guidelines on infection control in endoscopy.     

Disinfection of endoscopes from Helicobacter pylori-positive subjects: evaluation of the effectiveness of the Chinese Calijing disinfection kit

BACKGROUND: The aim of this study was to evaluate the effectiveness of the Calijing disinfection kit (an endoscope disinfection method used in Chinese hospitals) in eradicating Helicobacter pylori and assess whether use of the kit in 1994 during endoscopies in the Shandong Intervention Trial (SIT), Shandong, China, could have resulted in iatrogenic transmission of H pylori . METHODS: Bacterial culture studies at the Veterans Affairs Medical Center, Houston, Texas, using endoscopes and forceps from 49 H pylori -positive patients were performed on contaminated endoscopes before and after disinfection with the Calijing kit. RESULTS: At least 1 endoscope culture site was H pylori positive in 39 of 49 (79.6%) specimens predisinfection, whereas H pylori was not isolated from any endoscopic culture site postdisinfection. Non- H pylori bacteria and fungi were recovered from 22.6% of the postdisinfection cultures. CONCLUSION: Although no viable H pylori were recovered following the disinfection procedures, levels of H pylori below the detection threshold of the bacteriologic assay may have contributed to an increase in H pylori seroprevalence noted in the SIT. In addition, the kit was unable to provide disinfection against non- H pylori organisms, suggesting the need to adhere to internationally accepted disinfection procedures for endoscope reprocessing.     

Multi-state investigation of the actual disinfection/sterilization of endoscopes in health care facilities.

PURPOSE: The purpose of this investigation was to observe and assess the actual disinfection or sterilization of endoscopes in health care facilities. MATERIALS AND METHODS: A total of 22 hospitals and four ambulatory care centers in three states were studied. Facility protocols were reviewed, interviews conducted with relevant personnel, actual disinfection or sterilization procedures observed, and biologic tests performed to determine and assess disinfection/sterilization procedures. RESULTS: Fundamental errors observed during the course of the investigation included respective failures to time the period of disinfection, to clean all channels, to flush all channels with disinfectant, to fully immerse the endoscope in the disinfectant solution, and to use a disinfectant. At 78% of the facilities, failure to sterilize all biopsy forceps was observed. A total of 23.9% of the bacterial cultures from the internal channels of 71 gastrointestinal endoscopes grew 100,000 colonies or more of bacteria. These cultures were obtained after the completion of all disinfection/sterilization procedures and the device was deemed ready for use in the next patient. CONCLUSIONS: These data indicate that actual disinfection/sterilization procedures for endoscopes are not always optimal, and high-level disinfection of gastrointestinal endoscopes is not always achieved.     

Pseudomonas infection of the biliary system resulting from use of a contaminated endoscope

Pseudomonas aeruginosa was present in bile cultures from 10 patients who had undergone previous endoscopic retrograde cholangiopancreatography in 1984. After environmental cultures and review of instrument disinfection, we traced the infections to a single endoscope contaminated with P. aeruginosa, serotype 10. Although the instrument had been cleaned repeatedly with an automatic endoscope cleaning machine, P. aeruginosa survived on residual moisture left in the channels of the endoscope. Contamination ended only after we began to manually suction alcohol through the endoscope before air drying. In 5 of 10 patients, P. aeruginosa caused clinical infections including gangrenous cholecystitis, abscesses, and death. We could identify no factor that distinguished symptomatic from asymptomatic patients. In asymptomatic patients, P. aeruginosa was recovered from gallbladder bile up to 2 mo after endoscopic retrograde cholangiopancreatography. As this P. aeruginosa epidemic was discovered retrospectively because we monitor bile cultures, we advocate this practice as part of endoscopic retrograde cholangiopancreatography procedures.     

Cleaning and disinfection of equipment for gastrointestinal flexible endoscopy: interim recommendations of a Working Party of the British Society of Gastroenterology.

1. All patients undergoing gastrointestinal endoscopy must be considered 'at risk' for HIV and appropriate cleaning/disinfection measures taken for endoscopes and accessories. 2. Thorough manual cleaning with detergent, of the instrument and its channels is the most important part of the cleaning/disinfection procedure. Without this, blood, mucus and organic material will prevent adequate penetration of disinfectant for inactivation of bacteria and viruses. 3. Aldehyde preparations (2% activated glutaraldehyde and related products) are the recommended first line antibacterial and antiviral disinfectant. A four minute soak is recommended as sufficient for inactivation of vegetative bacteria and viruses (including HIV and HBV). 4. Quaternary ammonium detergents (8% Dettox for two minutes for bacterial disinfection), followed by exposure of the endoscope shaft and channels to ethyl alcohol (70% for four minutes for viral inactivation), is an acceptable second-line disinfectant routine where staff sensitisation prevents the use of an aldehyde disinfectant. 5. Accessories, including mouthguards and cleaning brushes, require similarly careful cleaning/disinfection, before and after each use. Disposable products (especially injection needles) may be used and appropriate items can be sterilised by autoclaving and kept in sterile packs. 6. Closed circuit endoscope washing machines have advantages in maintaining standards and avoiding staff sensitisation to disinfectants. Improved ventilation including exhaust extraction facilities may be required. 7. Endoscopy staff should receive HBV vaccination, wear gloves and appropriate protective garments, cover wounds or abrasions and avoid needlestick injuries (including spiked forceps, etc). 8. Known HIV-infected or AIDS patients are managed as immunosuppressed, and require protection from atypical mycobacteria/cryptosporidia etc, by one hour aldehyde disinfection of endoscopic equipment before and after the procedure. A dedicated instrument is not required. 9. Increased funding is necessary for capital purchases of GI endoscopic equipment, including extra and immersible endoscopes with additional accessories to allow for safe practice. 10. Greater numbers of trained GI assistants are needed to ensure that cleaning/disinfection recommendations and safety precautions are followed, both during routine lists and emergency endoscopic procedures. 11. These recommendations are based on expert interpretation of current data on infectivity and disinfection; they may require future modification.     

Preventing nosocomial infections from gastrointestinal endoscopy

Gastrointestinal procedures have been associated with a wide range of infectious complications, including bacterial endocarditis. Although the rate of bacteremia from the patient's own flora is quite high after some procedures, only a few cases of endocarditis caused by gastrointestinal instrumentation have been reported. Because of the severity of the illness, however, antibiotic prophylaxis has been recommended for patients who are categorized as high risk for some procedures. Bacteremia and other infections, such as colitis, may also originate from a contaminated endoscope. To prevent such an occurrence, high-level disinfection has been recommended for gastrointestinal endoscopes. High-level disinfection includes manual cleaning of the endoscope, flushing of internal channels with a liquid chemical sterilant, and thorough rinsing and drying of internal lumens.     

Disinfection of upper gastrointestinal fibreoptic endoscopy equipment: an evaluation of a cetrimide chlorhexidine solution and glutaraldehyde.

There is little information available on the bacteriological contamination of upper gastrointestinal fibreoptic endoscopes during routine use and the effects of 'disinfecting solutions'. A bacteriological evaluation was therefore made of cleaning an endoscope and its ancillary equipment with (1) water, (2) an aqueous solution of 1% cetrimide with 0.1% chlorhexidine, and (3) activated aqueous 2% glutaraldehyde. All equipment, but particularly the endoscope itself, was found to be heavily contaminated after use with a wide variety of organisms of which 53% were Gram positive. Cleaning the endoscope and ancillary equipment with water and the cetrimide/chlorhexidine solution alone or in combination was inadequate to produce disinfection but immersion in glutaraldehyde for two minutes consistently produced sterile cultures with our sampling technique. A rapid and simple method for disinfection of endoscopic equipment is therefore recommended and we think this is especially suitable for busy endoscopy units.     

ERCP in the Management of Choledocholithiasis in Pregnancy

The physiological changes of pregnancy increase the risk of gallstone formation, and choledocholithiaisis is the most common indication for endoscopic retrograde cholangiopancreatography (ERCP) during pregnancy. ERCP has been performed during pregnancy for over 20?years. Despite the apparent efficacy and lack of adverse fetal outcomes in published case series and reports, there remains a concern for the use of fluoroscopy during pregnancy. Recent focus has centered around avoidance of the use of fluoroscopy during ERCP, including the use of alternative techniques to confirm biliary cannulation and ductal clearance. The benefits of these techniques over traditional ERCP technique are unclear. In this article, we will review the epidemiology of gallstone disease during pregnancy, outline the risks of ERCP during pregnancy, and describe recent novel techniques in endoscopic biliary intervention for biliary drainage and ductal clearance.     

EXAMINATION OF RESPIRATORY AND CIRCULATORY DYNAMICS DURING EXAMINATION USING A THIN GASTROINTESTINAL ENDOSCOPE IN ADVANCED‐AGE SUBJECTS

Background: Endoscopic examination influences cardiovascular hemodynamics. Upper gastrointestinal examinations are currently performed with a thin endoscope. In the present study, respiratory and circulatory dynamics and autonomic nervous activity using a thin endoscope (XP260) or a standard endoscope (XQ240) were investigated. Methods: The subjects were 25 healthy adults aged less than 60 years (middle‐aged group) and 15 healthy adults aged 60 years or older (advanced‐age group). Percutaneous oxygen saturation, tonometric blood pressure, heart rate, and autonomic nervous activity were evaluated before the examination. After the endoscopic procedure, a questionnaire survey regarding examination‐related stress was conducted. Results: In the questionnaire survey, the proportion of subjects who answered ‘very stress free’ in the thin endoscope group was significantly higher than that in the standard endoscope group. The low frequency power of blood pressure variability (LF_BP), an indicator of sympathetic nervous activity, was significantly lower during the thin endoscopic procedure than during the standard endoscopic procedure. Moreover, the ratio of low frequency power to high frequency power of heart rate variability (LF_RR/HF_RR), an indicator of sympathetic nervous activity, was significantly lower during thin endoscopic procedure than during the standard endoscopic procedure. The maximum rates of change in the LF_BP and HF_RR powers in the advanced‐age group using thin and standard endoscopic procedures were significantly lower than in the middle‐aged group. Conclusions: The findings, although not in cross‐over study, suggest that a thin endoscope has a less marked influence on circulatory kinetics. Gastrointestinal endoscopic examinations using a thin endoscope might reduce complications related to endoscopic screening examinations in advanced‐age subjects.     

EFFICACY OF HIGH‐LEVEL DISINFECTANTS FOR GASTROINTESTINAL ENDOSCOPE DISINFECTION AGAINST STRONGYLOIDES STERCORALIS

Background: Guidelines for high‐level disinfection of gastrointestinal endoscopes have been published in many countries; however, none of them have a statement for disinfection against the parasite Strongyloides stercoralis. To establish a method for gastrointestinal endoscope disinfection against Strongyloides stercoralis, we examined the disinfection efficacy of high‐level disinfectants (3% glutaraldehyde, 0.55% ortho‐phthalaldehyde, and 0.3% peracetic acid) and 70% ethanol by in vitro tests. Methods: Strongyloides stercoralis larval suspension (0.05 mL) was added to 0.95 mL of each disinfectant and disinfection time measured under low magnification microscopy. Results: Among the high‐level disinfectants, peracetic acid was more efficacious for disinfection against Strongyloides stercoralis than glutaraldehyde and ortho‐phthalaldehyde. Ethanol was also efficacious for parasite killing. Conclusion: These results suggested that peracetic acid be recommended for gastrointestinal endoscope disinfection in regions with endemic Strongyloides stercoralis.     

The influence of endoscopic procedures upon the contamination of Helicobacter pylori cultures

BACKGROUND: Among the various diagnostic methods for the detection of Helicobacter pylori infection, histological examination and microbiological processing of gastric biopsy samples are assumed to be the gold standard techniques. AIMS: Since H. pylori culture can be affected by the presence of non-H. pylori bacteria, we evaluated the efficacy of endoscope disinfection and the influence of endoscopic procedures on culture contamination. PATIENTS AND METHODS: The procedures used during the first two routine endoscopies were evaluated during 28 consecutive days. Endoscopy room, forceps and endoscopic channel were analyzed before and after the beginning of normal procedures. After disinfection, a biopsy simulation was performed to verify the gastric bacteria. RESULTS: Endoscope disinfection removed all organisms from forceps and endoscopic channel with 100% efficacy. The most frequent non-H. pylori bacteria detected were Streptococcus bovis, Enterobacter hormaechei, and Staphylococcus aureus. The sensibility of the H. pylori culture was affected by the presence of non-H. pylori bacteria. CONCLUSION:The risk of transmission of microorganisms was not detectable when sterilized biopsy forceps and stringent disinfection standards were employed. Whilst S. bovis and E. hormaechei may be common in gastric microbial flora, the presence of P. aeruginosa and S. aureus indicated that the manipulation of biopsies could be responsible for culture contamination with these bacteria.     

ENDOSCOPIC PROCEDURE UNDER IRRIGATION

Background: Endoscopic therapy is often difficult to achieve particularly when the field of view of the lesion is poor due to contamination of mucus and blood. We developed five different types of end hoods that facilitate endoscopic procedures by simultaneously allowing various treatments and irrigation of the site. Methods: The end‐hood pieces were fabricated by drilling a side hole in the cap portion of conventional transparent hoods, then the irrigation tube was glued to the exterior surface of the hole. The fabricated transparent hood was placed at the tip of the endoscope. Results: Types 1 and 2 were useful for upper‐gastrointestinal (GI) hemorrhage, type 3 for lower‐GI hemorrhage, type 4 for endoscopic submucosal dissection and type 5 for endoscopic mucosal resection. Conclusions: With this method, endoscopic procedure is easy and economical, as therapeutic procedures can be performed under irrigation using a conventional endoscopy.     

HYGEA (Hygiene in gastroenterology--endoscope reprocessing): Study on quality of reprocessing flexible endoscopes in hospitals and in the practice setting

The quality of reprocessing gastroscopes, colonoscopes and duodenoscopes in daily routine of 25 endoscopy departments in hospitals and 30 doctors with their own practices was evaluated by microbiological testing in the HYGEA interventional study.In 2 test periods, endoscopes ready for use in patients were found contaminated at high rates (period 1: 49 % of 152 endoscopes; period 2: 39 % of 154 endoscopes). Culture of bacterial fecal flora (E. coli, coliform enterobacteriaceae, enterococci) was interpreted indicating failure of cleaning procedure and disinfection of endoscopes. Detection of Pseudomonas spp. (especially P. aeruginosa) and other non-fermenting rods - indicating microbially insufficient final rinsing and incomplete drying of the endoscope or a contaminated flushing equipment for the air/water-channel - pointed out endoscope recontamination during reprocessing or afterwards. Cause for complaint was found in more than 50 % of endoscopy facilities tested (period 2: 5 in hospitals, 25 practices). Reprocessing endoscopes in fully automatic chemo-thermally decontaminating washer-disinfectors with disinfection of final rinsing water led to much better results than manual or semi-automatic procedures (failure rate of endoscopy facilities in period 2 : 3 of 28 with fully automatic, 8 of 12 with manual, 9 of 15 with semi-automatic reprocessing). The study results give evidence for the following recommendations: 1. Manual brushing of all accessible endoscope channels has to be performed even before further automatic reprocessing; 2. For final endoscope rinsing, water or aqua dest. should only be used disinfected or sterile-filtered; 3. Endoscopes have to be dried thoroughly using compressed air prior to storage; 4. Bottle and tube for air/water-channel flushing have to be reprocessed daily by disinfection or sterilization, and in use, the bottle have to be filled exclusively with sterile water.The HYGEA study shows that microbiological testing of endoscopes is useful for detection of insufficient reprocessing and should be performed for quality assurance in doctors' practices, too. The study put recommendations for reprocessing procedures in more concrete terms.     

Disposable-sheath, flexible gastroscope system versus standard gastroscopes: a prospective, randomized trial.

BACKGROUND: Endoscopically transmitted infections due to inadequate disinfection are rare but well-recognized complications. A new prototype of a flexible, fiberoptic endoscope has been developed that uses a disposable sheath to cover and protect all working surfaces of the endoscope from contamination. The present study investigated the function, reprocessing, and hygienic status of this endoscope system in comparison with standard systems. METHODS: In a prospective, randomized trial, 100 upper endoscopic procedures (50 standard, 50 sheathed) were performed. Analog rating scales were used to evaluate endoscopic performance and reprocessing. Reprocessing time, procedure duration, insertion depth, total instrument downtime, and problems occurring during the procedure were recorded. Microbiologic swabs were obtained from each endoscope. RESULTS: Mean procedure duration was slightly longer with the sheathed system than with standard endoscope (9.9 vs. 8.4 min). Set up and reprocessing times, however, were significantly shorter with the Endosheath (8.9 vs. 48.4 min with the standard endoscope). The disposable-sheath endoscope system permits the rate of performance of procedures to be increased by a factor of up to 3.0. Both endoscopists and reprocessing personnel preferred the standard endoscope. No post-procedure sheath leakage or rupture was seen. CONCLUSION: Our results suggest that the "disposable endoscope" may have important advantages in terms of decreased instrument turn-around time and potentially improved safety.     

Differences in endoscopic views during biopsy through the right and left lower biopsy channels of the upper gastrointestinal endoscope

Background: It has not been established as to which side the biopsy (instrument) channel should be placed in the tip of a front‐viewing upper gastrointestinal (GI) endoscope to allow an en‐face approach to lesions on various aspects of the stomach wall. Methods: Using a front‐viewing two‐channel endoscope, we identi?ed a difference in endoscopic views during biopsy between lower‐right and lower‐left channels. Colored marks were distributed on the lesser curvature (LC), greater curvature (GC), anterior wall (AW), and posterior wall (PW) in the ‘stomach’ of a dummy for mock‐performance of upper GI endoscopy. When biopsy forceps through the different channels touched the marks, an endoscopic photograph was taken. Furthermore, when biopsy specimens were obtained from PW lesions in several patients, endoscopic views were compared between the two biopsy channels. Results: In the dummy study, no remarkable difference was detected in targeting the marks on AW, LC, or GC of the stomach. The dummy and the patient study showed that the lower‐right approach could target PW lesions with a more adequate endoscopic view than from the lower left. The lower‐left approach targeted PW lesions on the higher body with a nearly blinded endoscopic view. Specimens from PW of the upper body, which could be precisely obtained under direct visual control through the lower‐right channel, were no smaller than those obtained using the channel on the lower left. Conclusion: The present study suggests that the lower‐right channel may be preferable to the lower‐left channel in the tip of a front‐viewing upper GI endoscope.