A microbiological evaluation of level of disinfection for flexible cystoscopes protected by disposable endosheaths

Abstract

BackgroundFlexible cystoscopy is used in urological outpatient departments for diagnostic cystoscopy of bladder cancer and requires a high-level disinfection between each patient. The purpose of this study was to make a microbiological post disinfection efficacy assessment of flexible cystoscopes (FC) using disposable sterile endosheaths.MethodsOne hundred endosheaths underwent a leak-test for barrier integrity after cystoscopy. Microbiological samples from these cystoscopies were obtained; after removal of the endosheath, and after cleaning the scope with a detergent cloth, rinsing with tap water followed by 70% ethanol disinfection and subsequent drying. The number of colony forming units (cfu) from the samples was counted after 72 hours and then divided in three categories, Clean FC (<5 cfu/sample), Critical FC (5–50 cfu/sample) and High-risk FC (>50 cfu/sample). The result was compared with data of 10 years continuous control sampling recorded in the Copenhagen Clean-Endoscope Quality Control Database (CCQCD) and analyzed with a Chi-square test for homogeneity.ResultsAll 100 endosheaths passed the leak-test. All samples showed a Clean FC and low means of cfu. A query to the CCQCD, showed that 99.8% (1264/1267) of all FC with a built-in work-channel reprocessed in a WD were clean before use.ConclusionThe reprocessing of FC using endosheaths, as preformed in this study, provides a patient-ready procedure. The results display a reprocessing procedure with low risk of pathogen transmission, high patient safety and a valid alternative to the recommended high-level disinfection procedure of FC. However, the general impression was that sheaths slightly reduced vision and resulted in some patient discomfort.

A Systematic Review of Disposable Sheath Use During Flexible Endoscopy

“…Four teams of researchers (A, D, F, H) took samples for microbial cultures to evaluate the sheaths’ ability to prevent contamination of reusable endoscope components . These studies found no growth or low levels of growth in both sheathed and unsheathed endoscopes, with similar findings in each group (Table ).…”

“…In seven studies (A, F, H, I, K, L, R), researchers evaluated sheath durability. No breaches were detected in any sheaths . The authors of one study (I) noted that friction caused the sheath to cling to the cystoscope in 4 of 27 procedures, making its removal from the cystoscope difficult …”

“…Researchers in one study (B) reported aggregate findings for patients who underwent procedures with sheathed or unsheathed endoscopes and found that a high proportion of endoscopy patients were generally satisfied with the procedure (94%) and would recommend it to others (98%) . In addition to these systematic assessments of patient experience, researchers in four other studies (H, I, K, R) stated that the use of sheaths generally resulted in no additional discomfort or minor discomfort for patients …”

“…Authors of three articles (F, K, M) found costs for sheathed and unsheathed procedures were comparable . Seven studies (A, D, H, J, L, N, R) reported the cost per sheath could be offset by avoiding other costs associated with unsheathed procedures, including HLD or sterilization, additional staff time, physician downtime, instrument downtime, and patient sedation . The authors of one study (T) noted that sheaths are “portable, quick to change and minimize exposure to hazardous chemicals.” (p12) Another study (C) noted that additional costs can be expected if a sheath breaks during setup because an additional sheath will be required .…”

“…Some sheaths are simply coverings that fit tightly over external surfaces, similar to ultrasound probe covers. Other sheaths are more complex, with disposable channels incorporated into the sheath design (Figure ) . After a procedure is completed, personnel discard the sheaths and clean and disinfect the reusable endoscope components.…”