The investigators’ primary objective in this study was to assess the feasibility of high-volume single-day screening sigmoidoscopy as a means of addressing a prevailing concern among physicians regarding inefficient use of time and resources. The authors note that colorectal cancer continues to be a leading cause of cancer-related death in the U.S. and although compelling evidence exists to demonstrate that screening sigmoidoscopy can significantly reduce colorectal cancer mortality, this type of screening has yet to achieve national impact on colorectal cancer incidence or mortality. Consensus among medical professionals indicates this is largely due to poor patient acceptance and inadequate promotion and utilization by physicians, even by gastroenterologists. The secondary objective of the investigators in this study was to assess the performance and functional status of an innovative flexible fiberoptic sigmoidoscope (Vision Sciences®S-F100) with a single-use disposable sheath system (Vision Sciences® EndoSheath®Technology) for use in high-volume screening.
All municipal employees of a northeast city over the age of 50 yrs. (n=6137) were invited to undergo screening sigmoidoscopy free of charge, and were advised the sessions would be conducted on the weekend, at a prominent local hospital. A total of 227 individuals were scheduled, and pre-registration was efficiently handled the week before each session, to maximize potential for rapid patient turnaround time during the screening sessions. Patients were scheduled consecutively into 15 min. slots during 6 half-day (3 hr.) weekend sessions. Of the 227 scheduled, 86% (n=198) patients presented for the screening sessions. For this study, all screening procedures were performed with the Vision Sciences® S-F100 and disposable EndoSheath®Technology. The authors noted that the reusable components of this endoscopic system are similar to conventional fiberoptic sigmoidoscopes except that the scope itself does not contain air, water, or biopsy/suction channels. These channels are incorporated into the disposable sheath, which can be quickly removed and replaced between procedures; all parts that come into contact with the patient and/or the patient’s bodily fluids are disposed of after each use.
Study staff included an observer who recorded depth of sigmoidoscope insertion, procedure time, instrument set up time, and patient turnaround time. To reduce the potential for observation bias, the endoscopy nurse also documented patient turnaround time, which in turn provided a means for monitoring accuracy of procedure and instrument set up times. Total number of procedures per physician and per room were also recorded. Schroy et al reported that only 15% of the patients had undergone a previous sigmoidoscopy or colonoscopy, yet 32% acknowledged a positive family history of colorectal cancer or polyps.
Physicians performed a mean of 3.5 procedures per room per hour, or 4.7 procedures per hour overall; and the mean procedure time was 4.7 ± 3.3 mins. Equipment set up time and patient turnaround time averaged 4.6 ± 1.7 min. and 11.0 ± 6.0 min. respectively. There were no equipment malfunctions or technical difficulties. These results led the investigators to conclude that the use of the flexible fiberoptic sigmoidoscope and disposable sheath system was a highly expeditious and efficient approach. They found that as many as seven to eight procedures could be performed per hour by a single physician rotating between two endoscopy rooms. Schroy et al cited a previous study by Rothstein et al (1), which directly compared the performance status of the sheathed system versus a conventional system. In that study of 143 procedures, the authors found that procedure time was slightly longer with the sheathed system (5.6 min. vs. 6.7 min.), however, down time was considerably shorter with the sheathed system (32.8 vs. 8.1 min.). In the Schroy et al study, the authors noted that the sheathed sigmoidoscopy system minimized down time by eliminating elaborate and time-consuming high-level disinfection/sterilization routines between each procedure. In this study, a mean of only 4.6 min. was needed to unload and reload the S-F100 EndoSheath® Technology sigmoidoscope between procedures, compared with the >45 minutes currently recommended for conventional sigmoidoscopes by leading chemical germicide manufacturers to achieve high level disinfection. Minimized down time enabled the physicians to perform 3.7 procedures per room per hour with the S-F100 system vs. only a single procedure per room per hour had a conventional endoscopic system been used. The authors commented that this benefit could only be off set by the availability of an arsenal of conventional sigmoidoscopes, which is impractical in most settings, and extremely costly. The investigators also noted that in addition to its positive impact on efficient use of time and resources, the sheathed system offers a potential strategy for reducing the risk of endoscopically transmitted infectious complications and patient or staff reactions to harsh disinfectant solutions. It was suggested that although this study evaluated the performance of the sheath system for the purpose of high-volume screening, this system may well have distinct advantages in lower volume settings, such as private offices.
In conclusion, the authors discussed the validity of the study from a cost-effectiveness standpoint; and while it is understood that the issue of cost-effectiveness is extremely complex, they approached this by addressing comparable costs between the disposable sheathed system and a conventional endoscopic system. The capital equipment costs of the two systems were found to be comparable; the major differential costs to be considered were those of the sheaths and costs associated with reprocessing. It was noted that at face value the cost of the sheath was about $45 and the associated reprocessing cost was minimal; in contrast, the costs associated with reprocessing conventional sigmoidoscopes include costs for prolonged labor, specialized equipment (fume hoods, disinfection chambers, etc.), space, protective gear, chemical disinfectants, and cleaning supplies. The investigators commented that to obtain a meaningful cost comparison between the two systems, it is necessary to factor in procedural routines involved in using an un-sheathed conventional endoscopic system, which result in physician and nurse “idle time.” A previous study by Trowers et al (2) was cited to support the finding that increased patient turnaround and maximized effi ciency of time and resources provide a strong incentive for office-based sigmoidoscopy