Ascorbic acid PEG-2L is superior for early morning colonoscopies in colorectal cancer screening programs: a prospective non-randomized controlled trial.

BACKGROUND: The quality of colon cleansing and the tolerability of anterograde preparation are essential to the success of colorectal cancer screening. AIM: To compare the tolerability and efficacy of low-volume preparations vs the standard regimen in individuals scheduled for an early morning colonoscopy. STUDY: Participants in a population-based colorectal cancer screening program using the fecal immunochemical test who were scheduled for a colonoscopy from 09:00 a.m. to 10:20 a.m. were prospectively included and assigned to: (1) control group (PEG-ELS 4L): PEG 4L and electrolytes; (2) group AscPEG-2L: a combination of PEG and ascorbic acid 2L; and (3) group PiMg: sodium picosulfate and magnesium citrate 500 mL plus 2L of clear fluids. Tolerability was evaluated with a questionnaire and the quality of bowel preparation with the Boston Bowel Preparation Scale. RESULTS: A total of 292 participants were included: 98 in the PEG-ELS 4L control group, 96 in the AscPEG-2L study group and 98 in the PiMg study group. Low-volume treatments were better tolerated than the standard solution (AscPEG-2L 94.8% and PiMg 93.9% vs PEG-ELS 4L 75.5%; p < 0.0001). The effectiveness of AscPEG-2L was superior to that of PEG-ELS 4L and PiMg (p = 0.011 and p = 0.032, respectively). Patient acceptance was higher for single-dose than for split-dose administration but efficacy was higher with the split dose than with other doses. CONCLUSIONS: In early morning colonoscopies, ascPEG-2L appears to be the best option, especially when administered in a split-dose.

The role of a computed tomography-based image registered navigation system for natural orifice transluminal endoscopic surgery: a comparative study in a porcine model.

BACKGROUND AND STUDY AIMS: Most natural orifice transluminal endoscopic surgery (NOTES) procedures have been performed in animal models through the anterior stomach wall, but this approach does not provide efficient access to all anatomic areas of interest. Moreover, injury of the adjacent structures has been reported when using a blind access. The aim of the current study was to assess the utility of a CT-based (CT: computed tomography) image registered navigation system in identifying safe gastrointestinal access sites for NOTES and identifying intraperitoneal structures. METHODS: A total of 30 access procedures were performed in 30 pigs: anterior gastric wall (n = 10), posterior gastric wall (n = 10), and anterior rectal wall (n = 10). Of these, 15 procedures used image registered guidance (IR-NOTES) and 15 procedures used a blind access (NOTES only). Timed abdominal exploration was performed with identification of 11 organs. The location of the endoscopic tip was tracked using an electromagnetic tracking system and was recorded for each case. Necropsy was performed immediately after the procedure. The primary outcome was the rate of complications; secondary outcome variables were number of organs identified and kinematic measurements. RESULTS: A total of 30 animals weighting a mean (± SD) of 30.2 ± 6.8 kg were included in the study. The incision point was correctly placed in 11 out of 15 animals in each group (73.3 %). The mean peritoneoscopy time and the number of properly identified organs were equivalent in the two groups. There were eight minor complications (26.7 %), two (13.3 %) in the IR-NOTES group and six (40.0 %) in the NOTES only group ( P = n. s.). Characteristics of the endoscope tip path showed a statistically significant improvement in trajectory smoothness of motion for all organs in the IR-NOTES group. CONCLUSION: The image registered system appears to be feasible in NOTES procedures and results from this study suggest that image registered guidance might be useful for supporting navigation with an increased smoothness of motion.