Linhui Zhang

Water exchange enhanced cecal intubation in potentially difficult colonoscopy. Unsedated patients with prior abdominal or pelvic surgery: a prospective, randomized, controlled trial

BACKGROUND Colonoscopy is widely used for management of colorectal diseases. A history of abdominal or pelvic surgery is a well-recognized factor associated with difficult colonoscopy. Although water exchange colonoscopy (WEC) was effective in small groups of male U.S. veterans with such a history, its application in other cultural settings is uncertain. OBJECTIVE To investigate the application of WEC in such patients. DESIGN Prospective, randomized, controlled, patient-blinded study. SETTING Tertiary-care referral center in China. PATIENTS Outpatients with prior abdominal or pelvic surgery undergoing unsedated diagnostic, screening, or surveillance colonoscopy. INTERVENTION Patients were randomized to examination by either WEC or conventional air colonoscopy (AC). MAIN OUTCOME MEASUREMENTS Cecal intubation rate. RESULTS A total of 110 patients were randomized to the WEC (n = 55) or AC (n = 55) group. WEC significantly increased the cecal intubation rate (92.7% vs 76.4%; P = .033). The maximum pain scores (± standard deviation) were 2.1 ± 1.8 (WEC) and 4.6 ± 1.7 (AC), respectively (P < .001). Multivariate analysis showed that the colonoscopy method was the only independent predictor of failed colonoscopy (odds ratio 11.44, 95% confidence interval, 1.35-97.09). A higher proportion of patients examined by WEC would be willing to have a repeat unsedated colonoscopy (90.9% vs 72.7%, P = .013). LIMITATIONS Single center; unblinded but experienced endoscopists. CONCLUSION This randomized, controlled trial confirms that the water exchange method significantly enhanced cecal intubation in potentially difficult colonoscopy in unsedated patients with prior abdominal or pelvic surgery. The lower pain scores and higher proportion accepting repeat of the unsedated option suggest that WEC is promising. It may enhances compliance with colonoscopy in specific populations. ( CLINICAL TRIAL REGISTRATION NUMBER NCT01485133.).

Polysaccharide hemostatic system for hemostasis management in colorectal endoscopic mucosal resection

A new polysaccharide hemostatic system (EndoClotTM) was recently developed for bleeding control in gastrointestinal tract endoscopy; however, its efficacy and safety is not yet well established in colorectal endoscopic mucosal resection (EMR). The aim of the present study was to observe the bleeding control effect after EMR in the colorectum.

Delivery of Instructions via Mobile Social Media App Increases Quality of Bowel Preparation

BACKGROUND & AIMS Bowel preparation is closely linked to the quality of colonoscopy. We investigated whether delivery of instructions via a social media app increases the quality of colonoscopy by improving adequacy of bowel preparation. METHODS We performed a prospective study at 3 endoscopic centers in China of 770 colonoscopy outpatients (18-80 years old) with convenient access to Wechat (a widely used mobile social media app) from May through November 2014. Patients were randomly assigned to groups that received standard education along with delivery of interactive information via Wechat (n = 387) or standard education (controls, n = 383). The primary outcome was proportion of patients with adequate bowel preparation (Ottawa score <6). Secondary outcomes included rates of adenoma detection and cecal intubation, cecal intubation time, rates of incomplete compliance with instructions, and patient willingness to repeat bowel preparation. RESULTS Demographic features were comparable between the groups. A higher proportion of patients in the group that received social media instruction had adequate bowel preparation than the control group (82.2% vs 69.5%, P < .001). Among patients with successful colonoscopies, the group that received social media instruction had lower mean total and segmental Ottawa scores (P < .05). A higher proportion of patients receiving social media instruction also had cecal intubation (97.2% vs 93.2% in controls, P = .014) and were found to have adenomas (18.6% vs 12.0% in controls, P = .012). CONCLUSIONS Instruction via a mobile social media app, in conjunction with regular instruction, increases subjective measures of adequacy of bowel preparation. Use of the app significantly increased the proportion of patients with successful cecal intubation and in whom adenomas were detected, indicating increased quality of colonoscopy. ClinicalTrials.gov number: NCT02140827.

Water Exchange Method Significantly Improves Adenoma Detection Rate: A Multicenter, Randomized Controlled Trial.

Objectives:Adenoma detection rate (ADR) is a key colonoscopy quality indicator in Western clinical literature. Our low ADR prompted us to assess novel methods to improve performance. Western retrospective reports suggested that water exchange (WE) could increase ADR. However, most of these studies used pain score or intubation rate as the primary outcome. Here we test the hypothesis that WE significantly increases ADR among Chinese colonoscopists and design a prospective randomized controlled trial using ADR as our primary outcome.Methods:This prospective, randomized controlled trial was performed at six centers in China. Screening, surveillance, and diagnostic cases were randomized to be examined by WE or traditional air insufflation (AI) method. The primary outcome was ADR.Results:From April 2014 to July 2015, 3,303 patients were randomized to WE (n=1,653) and AI (n=1,650). The baseline characteristics were comparable. Overall ADR was 18.3% (WE) and 13.4% (AI) (relative risk 1.45, 95% confidential interval: 1.20–1.75, P<0.001). ADR in screening patients using AI was 25.8% (male) and 15.7% (female). ADR in screening patients aged >50 years old was 29.4% (WE) and 22.9% (AI) (relative risk 1.09, 95% confidential interval: 1.00–1.19, P=0.040). The increase by WE was reproducibly observed in all indication categories, and significant in screening and diagnostic cases. The limitation imposed by the unblinded investigators was mitigated by comparable inspection times in cases without polyps, similar adenoma per positive colonoscopy, and reproducible enhancement of ADR and adenoma per colonoscopy by WE across all eight investigators.Conclusions:This prospective study confirms Western retrospective data that WE significantly improves ADR among Chinese colonoscopists. WE may be superior to AI for screening colonoscopy in China. Colonoscopists elsewhere with low ADR might consider evaluating WE for performance improvement.

Left-colon water exchange preserves the benefits of whole colon water exchange at reduced cecal intubation time conferring significant advantage in diagnostic colonoscopy — a prospective, randomized controlled trial

Abstract Objectives: Whole-colon water exchange (WWE) reduces insertion pain, increases cecal intubation success and adenoma detection rate, but requires longer insertion time, compared to air insufflation (AI) colonoscopy. We hypothesized that water exchange limited to the left colon (LWE) can speed up insertion with equivalent results. Methods: This prospective, randomized controlled study (NCT01735266) allocated patients (18–80 years) to WWE, LWE or AI group (1:1:1). The primary outcome was cecal intubation time. Results: Three hundred subjects were randomized to the WWE (n = 100), LWE (n = 100) or AI group (n = 100). Ninety-four to ninety-five per cent of patients underwent diagnostic colonoscopy. Baseline characteristics were balanced. The median insertion time was shorter in LWE group (4.8 min (95%CI: 3.2–6.2)) than those in WWE (7.5 min (95%CI: 6.0–10.3)) and AI (6.4 min (95%CI: 4.2–9.8)) (both p < 0.001) groups. The cecal intubation rates in unsedated patients of the two water exchange methods (WWE 99%, LWE 99%) were significantly higher than that (89.8%) in AI group (p = 0.01). The final success rates were comparable among the three groups after sedation was given. Maximum pain scores and number of patients needing abdominal compression between WWE and LWE groups were comparable, both lower than those in AI group (p < 0.05). No significant difference was observed regarding PDR, although the PDR in right colon tended to be higher in WWE group. Conclusion: By preserving the benefits of WWE and reducing insertion time, LWE is appropriate for diagnostic colonoscopy, especially in settings with tight scheduling of patients. The higher PDR in the right colon in WWE group deserves to be further investigated.

Comparison of O-Type HybridKnife to Conventional Knife in Endoscopic Submucosal Dissection for Gastric Mucosal Lesions.

AbstractEndoscopic submucosal dissection (ESD) has been accepted as a minimal invasive alternative to surgery for localized superficial gastrointestinal neoplasms recently. However, the procedure remains to be technically challenging and time consuming. A new dissecting knife with partially insulated tip has been recently developed with built-in injection capability. The purpose of this study was to investigate whether the efficiency of ESD procedure could be improved with this new device.A total of 78 patients, who underwent ESD with gastric mucosal lesions including flat type polyps, adenoma or early gastric cancer, were randomly assigned to either ESD with O-type HybridKnife or conventional ESD knives without waterjet. Procedure time and related factors of ESD were analyzed.ESD procedure time was 43.0 (interquartile range, IQR 27.0–60.0) minutes in HybridKnife group compared to 60.5 (IQR 44.0–86.3) minutes in the control group (P = 0.001). There was no difference in the clinical outcome and the adverse event rate. The former demonstrated more favorable results in lesions ⩽4 cm of specimen size (P ⩽ 0.0001) and when located in the distal stomach (P = 0.001), also in lesions with fibrosis (P = 0.008). Multivariate regression analysis showed that O-type Knife (P ⩽ 0.0001), specimen size (P ⩽ 0.0001), and fibrosis (P ⩽ 0.0001) were independent predictors of procedure time.The O-type HybridKnife yielded faster procedure time compared to the conventional knives in gastric ESD with a similar safety profile.

Same-Day Single Dose of 2 Liter Polyethylene Glycol is Not Inferior to The Standard Bowel Preparation Regimen in Low-Risk Patients: A Randomized, Controlled Trial.

Objectives:Split dose of 4 l polyethylene glycol (PEG) is currently the standard regimen for bowel preparation (BP). However, it may be unnecessary for patients without high risks (e.g., old age, constipation, and diabetes, and so on) for inadequate BP. The study aimed to compare the efficacy of bowel cleansing between low-risk patients receiving same-day, single dose of low-volume (SSL) PEG vs. standard regimen.Methods:This prospective, randomized, observer-blinded, non-inferiority study enrolled low-risk patients in three centers. Patients undergoing colonoscopy were randomized (1:1) to the SSL or standard group. The primary outcome was adequate BP, defined by Boston Bowel Preparation Score (BBPS) ≥6 and each segmental score ≥2. Secondary outcomes included adverse events, cecal intubation rate, and patient willingness to repeat BP, and so on.Results:Among 2,532 patients eligible for the study, 940 (37.1%) were at low risk and 792 (31.3%) at high risk for inadequate BP. The low-risk patients were randomly allocated to the SSL (n=470) or standard group (n=470). The baseline characteristics of the two groups were similar. Intention-to-treat analysis showed that adequate BP was achieved in 88.1% in the SSL group and 87.0% in the standard group (relative risk (RR) 1.10, 95% confidence interval (CI): 0.75–1.63, P=0.621). The overall BBPS was 7.3±1.2 and 7.3±1.3, respectively (P=0.948). No significant differences were found between the two groups with regards to the right, transverse, and left-segmental colon BBPS (all P>0.05). However, in terms of adverse events, patients in the SSL group reported less nausea (19.6% vs. 29.9%), vomiting (5.3% vs. 11.4%), and abdominal discomfort (2.2% vs. 6.0%) compared with those in the standard group. More patients in the SSL group were willing to repeat BP (94.0% vs. 89.5%, P=0.015).Conclusions:For low-risk patients, the SSL regimen was not inferior to the split dose of 4 l PEG for adequacy of BP. Single dose of low-volume regimen had significantly fewer adverse events. This simplified regimen may be preferable in the “easy-to prepare” population.