Risk of Metachronous Advanced Colorectal Neoplasia After Removal of Diminutive Versus Small Nonadvanced Adenomas: A Multicenter Study.

BACKGROUND: Current postpolypectomy guidelines treat 1-9 mm nonadvanced adenomas (NAAs) as carrying the same level of risk for metachronous advanced colorectal neoplasia (ACRN). AIMS: To evaluate whether small (6-9 mm) NAAs are associated with a greater risk of metachronous ACRN than diminutive (1-5 mm) NAAs. METHODS: We retrospectively evaluated 10,060 index colonoscopies performed from July 2011 to June 2019. A total of 1369 patients aged ≥ 40 years with index NAAs and having follow-up examinations were categorized into 5 groups based on size and number of index findings: Group 1, ≤ 2 diminutive NAAs (n = 655); Group 2, ≤ 2 small NAAs (n = 529); Group 3, 3-4 diminutive NAAs (n = 78); Group 4, 3-4 small NAAs (n = 65); and Group 5, 5-10 NAAs (n = 42). Size was classified based on the largest NAA. ACRN was defined as finding an advanced adenoma or colorectal cancer at follow-up. RESULTS: The absolute risk of metachronous ACRN increased from 7.2% in patients with all diminutive NAAs to 12.2% in patients with at least 1 small NAA (P = 0.002). Patients in Group 2 (adjusted odds ratio [AOR] 1.89; 95% confidence interval [CI], 1.21-2.95), Group 3 (AOR 2.40; 95% CI 1.78-4.90), Group 4 (AOR 2.77; 95% CI 1.35-5.66), and Group 5 (AOR 3.71; 95% CI 1.65-8.37) were associated with an increased risk of metachronous ACRN compared with Group 1. CONCLUSIONS: Patients with small NAAs have an increased risk of metachronous ACRN. Postpolypectomy guidelines should consider including risk stratification between small and diminutive adenomas.

Comparison of polyp detection during both insertion and withdrawal versus only withdrawal of colonoscopy: A prospective randomized trial.

BACKGROUND AND AIMS: Polyps seen and not removed during colonoscope insertion are sometimes unable to be found during withdrawal. We aimed to evaluate whether additional inspection and polypectomy during insertion increases adenoma detection rate (ADR) compared with inspection and polypectomy entirely during withdrawal. METHODS: A total of 421 patients aged ≥ 45 years and undergoing colonoscopy were prospectively randomized to receive inspection and polypectomy during both insertion and withdrawal (study group) or inspection and polypectomy entirely during withdrawal (control group). The primary outcome was the ADR. Secondary outcomes included other adenoma-related parameters and procedure-related measures. RESULTS: Baseline demographics, procedure indications, preparation quality, total procedure time, sedative doses, colonoscopy difficulty, and patient discomfort were similar between the groups. The insertion time was significantly longer in the study group (11.1 ± 4.8 vs 6.2 ± 4.7 min, P < 0.0001). The withdrawal time was significantly longer in the control group (29.2 ± 9.8 vs 23.1 ± 7.9 min, P < 0.0001). There was no significant difference in the ADR (63.5% [study group] vs 68.1% [control group]), the mean adenoma per procedure (1.6 ± 2.0 vs 1.9 ± 2.4), or the mean adenoma per positive procedure (2.5 ± 2.0 vs 2.7 ± 2.5) between groups. The proximal colon ADR was significantly higher in the control group compared with the study group (56.2% vs 46.0%, P = 0.041). CONCLUSIONS: Additional inspection and polypectomy during colonoscope insertion did not improve ADR compared with inspection and polypectomy entirely during withdrawal. These results do not support an additional role for routine inspection during insertion (clinical trial registration number: NCT03444090).

Risk of Renal Injury After the Use of Polyethylene Glycol for Outpatient Colonoscopy: A Prospective Observational Study.

GOAL: The goal of this study was to estimate the risk of renal injury after the use of 3-L polyethylene glycol (PEG) before outpatient colonoscopy. BACKGROUND: Population-based studies showed that the use of PEG was associated with renal injury, but this association has not been confirmed by prospective study. STUDY: Patients ≥40 years of age with an estimated glomerular filtration rate ≥30 mL/min were screened for enrollment. Laboratory data were collected before, during, and after the colonoscopies. Patients with a ≥30% increase in baseline serum creatinine levels were followed until a peak level was detected. Renal injury included acute renal dysfunction (ARD) and acute kidney injury (AKI), defined as a 30% to 49% increase and ≥50% increase in creatinine levels compared with the baseline, respectively. RESULTS: A total of 1163 patients (mean age, 55.7 y) completed the study. Baseline and first postcolonoscopy laboratory data were obtained an average of 17.0 days before and 17.3 days after the colonoscopies were performed, respectively. Renal injury was identified in 32 patients; 26 patients (2.2%) had ARD, and 6 patients (0.5%) had AKI. All patients with renal injury recovered fully during follow-up. In the subgroup analysis, the use of nonsteroidal anti-inflammatory drugs (NSAIDs) before colonoscopy was statistically associated with the development of AKI (odds ratio, 6.5; 95% confidence interval, 1.2-35.5; P=0.03). CONCLUSIONS: This prospective study showed that the use of PEG was associated with a small risk of renal injury. NSAIDs use was statistically associated with AKI in the context of colonoscopy for which PEG was used for bowel preparation.

Optimal procedural sequence for same-day bidirectional endoscopy with moderate sedation: A prospective randomized study.

BACKGROUND AND AIM: Same-day bidirectional endoscopy (BDE) is a commonly performed procedure, but the optimal sequence for the procedure with moderate conscious sedation is not well established. This study investigated the optimal sequence for same-day BDE under moderate conscious sedation and carbon dioxide insufflation in terms of sedation doses, patient discomfort, and colonoscopy performance. METHODS: A prospective randomized controlled study of 120 patients who were scheduled for BDE examination was performed. Colonoscopy followed by esophagogastroduodenoscopy (EGD) examination was performed in 60 patients (colonoscopy-EGD group), and EGD followed by colonoscopy examination was performed in another 60 patients (EGD-colonoscopy group). Endoscopists and patients completed a questionnaire to assess objective and subjective discomfort. RESULTS: Baseline demographics, procedure indications, bowel preparation quality, cecal intubation rate/time, colonoscopy withdrawal time, endoscopic interventions, BDE procedure time, colon polyp/adenoma detection rates, patient discomfort, and adverse events were similar between the two study groups. The total doses of fentanyl and midazolam were significantly higher for the colonoscopy-EGD group than for the EGD-colonoscopy group (83.4 ± 17.7 vs 68.7 ± 18.6 µg and 6.3 ± 1.4 vs 5.2 ± 1.3 mg, P < 0.0001 and P < 0.0001, respectively). The recovery time to discharge was significantly longer for the colonoscopy-EGD group than for the EGD-colonoscopy group (43.5 ± 16.2 vs 34.5 ± 8.9 min, P = 0.0003). CONCLUSIONS: Esophagogastroduodenoscopy followed by colonoscopy is the optimal sequence for same-day BDE under moderate conscious sedation and carbon dioxide insufflation. Following this order allows for a reduction of sedation doses and for shorter recovery times.

Predictors of Suboptimal Bowel Preparation Using 3-l of Polyethylene Glycol for an Outpatient Colonoscopy: A Prospective Observational Study.

BACKGROUND: A 3-l polyethylene glycol (PEG) solution provided better bowel cleansing quality than a 2-l solution for outpatient colonoscopy. Predictors of suboptimal preparation using a 3-l PEG have not been previously reported. AIMS: To investigate the possible predictors of suboptimal bowel preparation using 3-l of PEG. METHODS: We analyzed a database of 1404 consecutive colonoscopies during a 27-month period at a community hospital. A split-dose PEG regimen was provided for morning colonoscopies, and a same-day PEG regimen was provided for afternoon colonoscopies. The level of bowel cleansing was prospectively scored according to the Boston Bowel Preparation Scale (BBPS). Possible predictors of suboptimal colon preparation, defined as a BBPS score <7, were analyzed using univariate statistics and multivariate logistic regression models. RESULTS: The mean age of the study population (46.7 % men) was 52.5 years (range 20-80 years, SD 11.1 years), and the majority of patients (77.6 %) underwent morning colonoscopies. A suboptimal bowel preparation was reported in 17.2 % of the observed colonoscopies. In the multivariate regression analysis, constipation (odds ratio [OR] 1.60, 95 % confidence interval [CI] 1.15-2.22), male gender (OR 1.68, 95 % CI 1.25-2.25), obesity (OR 1.76, 95 % CI 1.29-2.41), and inadequate (<80 %) PEG consumption (OR 5.4, 95 % CI 2.67-10.89) were independent predictors of a suboptimal colon preparation. CONCLUSIONS: This prospective study identified that constipation, male gender, obesity, and inadequate intake of PEG were significant risk factors for suboptimal bowel preparation using a 3-l PEG solution for outpatient colonoscopy. Interventions of optimized colonoscopy preparation should be targeted at these patient populations.

Residual Gastric Volume After Bowel Preparation With Polyethylene Glycol for Elective Colonoscopy: A Prospective Observational Study.

GOAL: To examine the residual gastric volume (RGV) in colonoscopy after bowel preparations with 3-L polyethylene glycol (PEG). BACKGROUND: Obstacles to high-volume bowel preparation by anesthesia providers resulting from concerns over aspiration risk are common during colonoscopy. STUDY: Prospective measurements of RGV were performed in patients undergoing esophagogastroduodenoscopy (EGD) and morning colonoscopy with split-dose PEG preparation, patients undergoing EGD and afternoon colonoscopy with same-day PEG preparation, and patients undergoing EGD alone under moderate conscious sedation. Colonoscopy patients were allowed to ingest clear liquids until 2 hours before the procedure. Patients undergoing EGD alone were instructed to eat/drink nothing after midnight. RESULTS: There were 860 evaluated patients, including 330 in the split-dose preparation group, 100 in the same-day preparation group, and 430 in the EGD-only group. Baseline demographics and disease/medication factors were similar. The mean RGV in patients receiving the same-day preparation (35.4 mL or 0.56 mL/kg) was significantly higher than that in patients receiving the split-dose preparation (28.5 mL or 0.45 mL/kg) and in patients undergoing EGD alone (22.8 mL or 0.36 mL/kg) (P=0.023 and P<0.0001, respectively). Within the bowel-preparation groups, patients with fasting times of 2 to 3 hours had similar RGV compared with patients who had fasting times >3 hours. The shape of the distribution and the range of RGV among the 3 study groups were similar. No aspiration occurred in any group. CONCLUSIONS: PEG bowel preparations increase RGV mildly, but seem to have no clinical significance. These results support the current fasting guidelines for colonoscopy.

Impact of Bowel Preparation with Low-Volume (2-Liter) and Intermediate-Volume (3-Liter) Polyethylene Glycol on Colonoscopy Quality: A Prospective Observational Study.

BACKGROUND/AIMS: Two-liter polyethylene glycol (PEG) is the most commonly used bowel-cleansing regimen in Taiwan, but its efficacy is unsatisfactory. The aim of this study was to compare 2-liter and 3-liter PEG in terms of their impact on colonoscopy quality among an average-risk population. METHODS: Two-liter PEG was provided between August 2012 and May 2013, while 3-liter PEG was provided between June 2013 and March 2014. A split-dose regimen was provided for morning colonoscopy and a same-day regimen was provided for afternoon colonoscopy. The level of bowel cleansing was prospectively scored. RESULTS: A total of 407 consecutive subjects completed the 2-liter regimen, and another 407 consecutive subjects completed the 3-liter regimen. The 3-liter group had a significantly higher rate of excellent or good preparations, equivalent to a Boston bowel preparation scale of ≥7, than the 2-liter group (90 vs. 73%, p < 0.0001). More subjects in the 3-liter preparation group compared with the 2-liter group had overall adenoma (70 vs. 54%, p < 0.0001), proximal adenoma (47 vs. 35%, p = 0.0006), sessile serrated adenoma (28 vs. 6%, p < 0.0001), and advanced adenoma (21 vs. 9%, p < 0.0001). CONCLUSIONS: Three-liter PEG provided better cleansing quality and higher adenoma detection rate than 2-liter PEG.