Methods of luminal distention for colonoscopy

Gas Pressure From the Endoscope: An Unexplored Contributor to Morbidity and Mortality?

Background It has been shown that the incidence of venous air embolism and venous carbon dioxide (CO₂) embolism is high during endoscopic retrograde cholangiopancreatography (ERCP). We examined insufflating gas flow and maximum pressure produced by three types of commonly used endoscopes because we could not readily locate technical data for endoscope gas flow and maximum emitted pressure in the manufacturer's manuals. Methods We tested the Olympus GIF-Q180 used for esophagogastroduodenoscopy, the CF-Q180 used for colonoscopy, and the TJF-Q180 used for ERCP (Olympus America Inc., Center Valley, Pennsylvania). Under three different clinical gas insufflation scenarios, we measured in vitro maximum gas pressure transduced from a closed space created at the endoscope tip in a worst-case scenario analysis. Results We showed that it is readily possible to generate a pressure (>5-30 times normal central venous pressure) in the air space at the tip of all three endoscopes when insufflation is activated and the gas egress is limited. Conclusions These findings shed additional light on in vivo occurrences of gas embolism during gastrointestinal endoscopy. We postulate that in addition to using exclusively CO₂ as the insufflating gas, the risk of gas embolism can be further diminished by regulating insufflating gas pressure at the tip of endoscopes.

A prospective randomized controlled trial of the safety and efficacy of carbon dioxide insufflation compared with room air insufflation during gastric endoscopic submucosal dissection

BACKGROUND AND AIM

Carbon dioxide (CO₂ ) insufflation during gastric endoscopic submucosal dissection (GESD) under sedation can be used instead of room air insufflation. Appropriate monitoring of the partial pressure of CO₂ during GESD is necessary due to the impaired respiration. The aim of this study was to assess the safety and efficacy of CO₂ insufflation during GESD compared with conventional room air insufflation.

METHODS

Patients with a gastric epithelial neoplasm or early gastric cancer were enrolled. A total of 76 consecutive patients were randomly assigned to the CO₂ insufflation group (CO₂ group) or the room air insufflation group (air group). The primary outcome was the mean difference of end-tidal CO₂ (EtCO₂ ) between two groups.

RESULTS

The upper bound of the 95% CI for the mean EtCO₂ difference between the two groups before the procedure and at 15, 30 and 45 min after insufflation met the criteria for noninferiority. In a subgroup analysis of patients 70 years and older, the mean difference of EtCO₂ was not significantly different between two groups. However, the air group received more analgesics than the CO₂ group after the procedure (67.6% vs 35.1%, P = 0.005). In addition, in terms of improvement of abdominal pain or bowel gas after 24 h of GESD, CO₂ group showed better results than air group (both P < 0.05).

CONCLUSIONS

CO₂ insufflation during GESD is as safe as using room air, and patients, including elderly patients, receiving CO₂ achieve more rapid relief of abdominal pain and intra-abdominal residual gas during and after the procedure.

Colonoscopy-related colonic ischemia

Colonoscopy is a risk factor for colon ischemia. The colon is susceptible to ischemia due to its minor blood flow compared to other abdominal organs; the etiology of colon ischemia after colonoscopy is multifactorial. The causative mechanisms include splanchnic circulation impairment, bowel preparation, drugs used for sedation, bowel wall ischemia due to insufflation/barotrauma, and introduction of the endoscope. Gastroenterologists must be aware of this condition and its risk factors for risk minimization, early diagnosis, and proper treatment.

Closure of colonic deep mural injury and perforation with endoclips

INTRODUCTION

colorectal perforations are one of the most feared complications after performing an endoscopic resection. The use of endoclips is considered for the management of these complications.

OBJECTIVES

to evaluate the efficacy and safety of the use of endoclips in the management of perforations and deep mural injuries that occur after an endoscopic colorectal resection.

METHODS

a prospective cohort of consecutively included patients was used with a diagnosis of perforation or deep mural injury after an endoscopic colorectal resection treated with endoclips in our institution. The rates of perforation and deep mural injury were obtained. The factors associated with an unfavorable evolution after the placement of the endoclips were analyzed.

RESULTS

after 342 endoscopic mucosal resections (EMR) and 42 endoscopic submucosal dissections (ESD), there were 25 cases with perforation or deep mural injury. The deep mural injury rate was 3.22 % and 7.14 % in the case of EMR and ESD, respectively. The perforation rate was 1.46 % and 14.29 % in the case of EMR and ESD, respectively. Successful closure with endoclips was achieved in 24 cases (96 %). Only one patient presented an unfavorable evolution (10 %) after successful closure. The factors associated with an unfavorable evolution were the presence of diffuse peritoneal symptoms and a perforation size greater than or equal to 10 mm.

CONCLUSION

endoscopic closure with endoclips is effective to avoid surgery in cases of deep mural injury or perforation after an endoscopic resection.

Transanal access port (TrAAP) technique: the use of a single incision laparoscopic surgical port during canine colonoscopy (a cadaveric study)

BACKGROUND

Transanal colonoscopy using the single-incision laparoscopic surgical port is routinely used in human patients but has not been described in veterinary literature. The purpose of this study was to describe a novel access technique elucidating its endoscopic clinical potential and benefits. Additionally, its challenges, limitations, and clinical usability will be discussed and critiqued. The aim of this study was to describe the feasibility of the single-incision laparoscopic surgical port (SILS) as a transanal access technique in canine cadavers and compare its technical capabilities and economic value when compared to the traditional approaches of digital pressure and purse string.

RESULTS

The overall time to reach an intraluminal pressure of 10 mmHg was faster for digital pressure versus purse string (p = 0.05) and faster for single-incision laparoscopic surgical port versus purse string (p < 0.02). Maximum luminal pressure was significantly higher between single-incision laparoscopic surgical port and purse string (p = 0.001). Mean pressure for both the complete 60 s trial and during the last 45 s of insufflation were highest with the SILS port and were significantly different between the single-incision laparoscopic surgical port versus purse string (p = 0.0001, p < 0.0001) and digital pressure versus purse string (p < 0.005, p < 0.01) respectively. Complete luminal distention and visualization was observed in all trials.

CONCLUSIONS

The SILS port in a cadaveric canine model allowed good visualization of the rectal and colonic mucosa, provided constant insufflation of the colon and was feasible and subjectively easy to perform. Technical differences between techniques were observed with the use of the SILS port allowing for potentially lower personnel requirements, less procedural associated cost, less variability versus the digital pressure technique between assistants, and the ability of additional instruments to be used for procedures.

Hydro-jet propelled colonoscopy: proof of concept in a phantom colon

BACKGROUND

Colonoscopy is a widely used and effective procedure, but it often causes patient discomfort and its execution requires considerable skill and training. We demonstrate an alternative approach to colonoscope propulsion with the potential to minimise patient discomfort by reducing the forces exerted on the colonic wall and mesentery, and to reduce the level of skill required for execution.

METHODS

A prototype colonoscopic device is described, consisting of a tethered capsule that is propelled and manoeuvred through a water-filled colon (hydro-colonoscopy) by an array of water jets. As an initial proof of concept, experiments were performed to assess the ability of the device to navigate through a simplified PVA cryogel human colon phantom arranged in various anatomical configurations.

RESULTS

The prototype was capable of successfully navigating through three out of four colon configurations: a simple layout, alpha loop and reverse alpha loop. It was unable to negotiate the fourth configuration involving an "N loop", but this was attributed to problems with the colon phantom. In the successful test replicates, mean complete insertion (i.e. caecal intubation) time was 4.7 min. Measured pressures, temperatures and forces exerted on the colon appeared to be within a physiologically acceptable range. The results demonstrate the viability of propelling a colonoscope through a colon phantom using hydro-jets.

CONCLUSIONS

Results indicate that this approach has the potential to enable rapid and safe caecal intubation. This suggests that further development towards clinical translation is worthwhile.

Explosive Vomiting Associated with Proximal Colonic Distention during a Difficult Propofol-Assisted Colonoscopy

We present a case of explosive vomiting associated with the extensive manipulation of the proximal colon during a difficult colonoscopy procedure. The cause of vomiting in this case may have been multifactorial; however, proximal colonic distention was the most likely factor because the onset of vomiting coincided with proximal colonic manipulation and happened without any prodromal signs, coughing, and airway obstruction. Propofol, the sedative most commonly administered to the patient during colonoscopy, allows for a deep state of sedation, and consequently extensive colonic distention and scope manipulation. Colonic distention may lead to a higher risk of vomiting. We reviewed the neurocircuitry associated with vomiting and discussed why proximal colonic distention may increase the risk of vomiting. We emphasize vigilance during the manipulation of the proximal colon because vomiting increases the potential for aspiration pneumonitis and pneumonia in patients under deep propofol sedation with attenuated airway responses.

A Soft Pneumatic Inchworm Double balloon (SPID) for colonoscopy

The design of a smart robot for colonoscopy is challenging because of the limited available space, slippery internal surfaces, and tortuous 3D shape of the human colon. Locomotion forces applied by an endoscopic robot may damage the colonic wall and/or cause pain and discomfort to patients. This study reports a Soft Pneumatic Inchworm Double balloon (SPID) mini-robot for colonoscopy consisting of two balloons connected by a 3 degrees of freedom soft pneumatic actuator. SPID has an external diameter of 18 mm, a total length of 60 mm, and weighs 10 g. The balloons provide anchorage into the colonic wall for a bio-inspired inchworm locomotion. The proposed design reduces the pressure applied to the colonic wall and consequently pain and discomfort during the procedure. The mini-robot has been tested in a deformable plastic colon phantom of similar shape and dimensions to the human anatomy, exhibiting efficient locomotion by its ability to deform and negotiate flexures and bends. The mini-robot is made of elastomer and constructed from 3D printed components, hence with low production costs essential for a disposable device.

Efficacy and safety of carbon dioxide insufflation versus air insufflation during endoscopic retrograde cholangiopancreatography in randomized controlled trials: a systematic review and meta-analysis

Background and study aims  Ambient air is the most commonly used gas for insufflation in endoscopic procedures worldwide. However, prolonged absorption of air during endoscopic examinations may cause pain and abdominal distension. Carbon dioxide insufflation (CO ₂ i) has been increasingly used as an alternative to ambient air insufflation (AAi) in many endoscopic procedures due to its fast diffusion properties and less abdominal distention and pain. For endoscopic retrograde cholangiopancreatography (ERCP), use of CO ₂ for insufflation is adequate because this procedure is complex and prolonged. Some randomized controlled trials (RCTs) have evaluated the efficacy and safety of CO ₂ as an insufflation method during ERCP but presented conflicting results. This systematic review and meta-analysis with only RCTs evaluated the efficacy and safety of CO ₂ i versus AAi during ERCP. Methods  A literature search was performed using online databases with no restriction regarding idiom or year of publication. Data were extracted by two authors according to a predefined data extraction form. Outcomes evaluated were abdominal pain and distension, complications, procedure duration, and CO ₂ levels. Results  Eight studies (919 patients) were included. Significant results favoring CO ₂ i were less abdominal distension after 1 h (MD: -1.41 [-1.81; -1.0], 95 % CI, I² = 15 %, P  < 0.00001) and less abdominal pain after 1 h (MD: -23.80 [-27.50; -20.10], 95 %CI, I² = 9 %, P  < 0.00001) and after 6 h (MD: -7.00 [-8.66; -5.33]; 95 % CI, I² = 0 %, P  < 0.00001). Conclusion  Use of CO ₂ i instead of AAi during ERCP is safe and associated with less abdominal distension and pain after the procedure.

Can Water Exchange Improve Patient Tolerance in Unsedated Colonoscopy A Prospective Comparative Study

Background & Aims

Unsedated colonoscopy can be painful, poorly tolerated by patients, and associated with unsatisfactory technical performance. Previous studies report an advantage of water exchange over conventional air insufflation in reducing pain during unsedated colonoscopy. Our goal was to analyze the impact of water exchange colonoscopy on the level of maximum pain reported by patients submitted to unsedated colonoscopy, compared to conventional air insufflation.

Methods

We performed a single-center, patient-blinded, prospective randomized comparative study, where patients were either allocated to the water group, in which the method of colonoscopy used was water exchange, or the standard air group, in which the examination was accomplished with air insufflation.

Results

A total of 141 patients were randomized, 70 to the water and 71 to the air group. The maximum level of pain reported by patients during unsedated colonoscopy, measured by a numeric scale of pain (0-10), was significantly lower in the water group (3.39 ± 2.32), compared to the air group (4.94 ± 2.10), p < 0.001. The rate of painless colonoscopy was significantly higher in the water group (12.9 vs. 1.4%, p = 0.009). There were no significant differences between the two groups regarding indications for the procedure, quality of bowel preparation, cecal intubation time, withdrawal time, number of position changes, adenoma detection rate, and postprocedural complications. Only the number of abdominal compressions was significantly different, showing that water exchange decreases the number of compressions needed during colonoscopy.

Conclusions

Water exchange was a safe and equally effective alternative to conventional unsedated colonoscopy, associated with less intraprocedural pain without impairing key performance measures.

Carbon dioxide insufflation during colonoscopy in inflammatory bowel disease patients: a double-blind, randomized, single-center trial

OBJECTIVE

Bowel distension by insufflated air causes abdominal discomfort after colonoscopy. Carbon dioxide (CO2) instead of air insufflation during colonoscopy can reduce postprocedural discomfort in diagnostic and screening cases. Discomfort after colonoscopy and CO2 insufflation have never been studied in inflammatory bowel disease (IBD) patients, characterized by younger age, structural changes of the colon, and need for repeated and frequently uncomfortable colonoscopies. Our trial was designed to evaluate postprocedural discomfort associated with CO2 compared with air insufflation in unsedated or minimally sedated patients with known IBD.

METHODS

In a double-blind, randomized, single-center study, 64 patients were randomized to either CO2 insufflation (CO2) or air insufflation colonoscopy (Air). Abdominal pain, bloating, and flatulence scores during 24 h after colonoscopy were recorded using a continuous scale of 0-10 (0=none, 10=maximum discomfort). The primary endpoint used for power calculation was bloating score at 1 h after colonoscopy.

RESULTS

Pain, bloating, and flatulence scores at end, 1, and 3 h after colonoscopy were significantly lower in CO2 than in Air arm (P<0.001). Scores at 6, 12, and 24 h were comparable. Procedural parameters such as cecal and terminal ileum intubation rate, intubation and total time, pain during insertion, need for repositioning, and abdominal compression were not different between arms. No complications were recorded in the study.

CONCLUSION

Compared with air, CO2 insufflation significantly reduces abdominal pain, bloating, and flatulence scores during at least 3 h after colonoscopy in IBD patients, achieving comparable intraprocedural outcomes.

Impact of carbon dioxide insufflation and water exchange on postcolonoscopy outcomes in patients receiving on-demand sedation: a randomized controlled trial

BACKGROUND AND AIMS

Water exchange (WE) is the least painful insertion method during colonoscopy. Its impact on postcolonoscopy discomfort has not been well-described. Carbon dioxide (CO₂) insufflation consistently reduced postcolonoscopy discomfort. We compared postcolonoscopy outcomes of various combinations of insertion and withdrawal techniques (insertion-withdrawal modality): WE-CO₂, WE-air insufflation (WE-AI), and CO₂-CO₂.

METHODS

A total of 240 patients undergoing on-demand sedation diagnostic colonoscopy were randomized to WE-CO₂ (n = 79), WE-AI (n = 80), CO₂-CO₂ (n = 81), with postprocedural data collected up to 24 hours. The primary outcome was postcolonoscopy bloating. Other postcolonoscopy outcomes included pain scores, flatus and incontinence episodes, toilet use, interference with normal activities, patient satisfaction, and patient willingness to repeat the procedure.

RESULTS

Demographic and procedural data were comparable. Compared with WE-AI, WE-CO₂ and CO₂-CO₂ resulted in significantly less bloating (all P < .0005) and lower pain scores (P values ranged from .008 to < .0005) up to 3 hours and fewer flatus episodes up to 6 hours (P values ranged from .003 to < .0005). WE-CO₂ resulted in less interference with same-day activities compared with WE-AI (P = .043). The differences in postprocedural outcomes were significant, but the magnitude was small. Patient satisfaction and willingness to repeat the procedure were high and comparable among groups. WE was the least painful insertion technique (P < .0005).

CONCLUSIONS

The combination WE-CO₂ appears to be the optimal choice to decrease pain during the examination and to reduce bloating and other undesired procedural outcomes afterward. If a CO₂ insufflator is already available, it seems advisable to adopt the combination WE-CO₂. In the absence of a CO₂ insufflator, the cost effectiveness of the addition of withdrawal CO₂ to WE in diagnostic and nondiagnostic settings needs to be critically assessed. (Clinical trial registration number: NCT02409979.).

Painless Colonoscopy: Available Techniques and Instruments

During colonoscopy, air insufflation to distend the lumen and facilitate careful inspection and scope insertion can induce pain and cause discomfort. Carbon dioxide (CO₂) insufflation can decrease abdominal pain and discomfort during and after colonoscopy. The advantage of CO₂ insufflation is the rapid absorption of the gas across the intestine. Another painless option is water-assisted colonoscopy. Two methods for water-assisted colonoscopy are available: water immersion and water exchange. In a recent direct comparison, the water exchange method was superior to water immersion, CO₂ insufflation, and air insufflation with respect to pain during colonoscopy, although it still had the disadvantage of being a time-consuming procedure. Cap-assisted colonoscopy is a simple technique involving the use of a small transparent cap attached to the tip of the scope. Three studies showed an advantage of this technique in terms of reduced patient discomfort compared with the conventional method. Three robotic colonoscopy systems (Endotics System [Era Endoscopy], NeoGuide [NeoGuide Systems Inc.], and Invendoscope [Invendo Medical]) have been introduced to evaluate pain reduction during colonoscopy, but none has been widely adopted and used in practice. In this review, clinical trials of several techniques and new devices for painless colonoscopy are described and summarized.

Update on Difficult Polypectomy Techniques

Endoscopists often encounter colon polyps that are technically difficult to resect. These lesions traditionally were managed surgically, with significant potential morbidity and mortality. Recent advances in endoscopic techniques and instruments have allowed endoscopists to safely and effectively remove colorectal lesions with high technical and clinical success and potentially avoid invasive surgery. Endoscopic mucosal resection (EMR) has gained acceptance as the first-line therapy for large colorectal lesions. Endoscopic submucosal dissection (ESD) has been reported to be associated with higher rate of en bloc resection and less risk of short-time recurrence, but with an increased risk of adverse events. Therefore, the role of colorectal ESD should be restricted to lesions with high-risk morphologic features of submucosal invasion. In this article, we review the recent literature on the endoscopic management of difficult colorectal neoplasms.

Developing the Pediatric Gastrointestinal Endoscopy Unit: A Clinical Report by the Endoscopy and Procedures Committee

There is significant variability in the design and management of pediatric endoscopy units. Although there is information on adult endoscopy units, little guidance is available to the pediatric endoscopy practitioner. The purpose of this clinical report, prepared by the NASPGHAN Endoscopy and Procedures Committee, is to review the important considerations for setting up an endoscopy unit for children. A systematic review of the literature was undertaken in the preparation of this report regarding the design, management, needed equipment, motility setup, billing and coding, and pediatric specific topics.

Endoscopic mucosal resection and endoscopic submucosal dissection of large colonic polyps

Almost all large and complex colorectal polyps can now be resected endoscopically. Piecemeal endoscopic mucosal resection (PEMR) is an established technique with fairly low complication risk and good short-term and medium-term outcomes. Several modifications to the basic injection and snare technique have been developed contributing to safer and more complete resections. Delayed bleeding requiring reintervention is the most troublesome complication in 2-7% of patients, particularly in those with comorbidities and large, right-sided polyps. Endoscopic submucosal dissection (ESD) has become popular in Japan and has theoretical advantages over PEMR in providing a complete, en bloc excision for accurate histological staging and reduced local recurrence. These advantages come at the cost of a more complex, expensive and time-consuming procedure with a higher risk of perforation, particularly early in the procedure learning curve. These factors have contributed to the slow adoption of ESD in the West and the challenge to develop new devices and endoscopic platforms that will make ESD easier and safer. Currently, ESD indications are limited to large rectal lesions, in which procedural complications are easily managed, and for colorectal polyps with a high risk of containing tiny foci of early submucosally invasive cancer, whereby ESD may be curative compared with PEMR.

Design and control of a novel gastroscope intervention mechanism with circumferentially pneumatic-driven clamping function

BACKGROUND

Robot-assisted manipulation is promising for solving problems such as understaffing and the risk of infection in gastro-intestinal endoscopy. However, the commonly used friction rollers in few existing systems have a potential risk of deforming flexible endoscopes for non-uniform clamping.

METHODS

This paper presents a robotic system for a standard flexible endoscope and focuses on a novel gastroscope intervention mechanism (GIM), which provides circumferentially uniform clamping with an airbag. The GIM works with a relay-on mechanism in a way similar to manual operation. The shear stiffness of airbag and the critical slipping force (CSF) were analysed to determine the parameters of the airbag. A fuzzy PID controller was employed to realize a fast response and high accuracy of pneumatic actuation. Experiments were performed to evaluate the accuracy, stiffness and CSF. In vitro and in vivo animal experiments were also carried out.

RESULTS

The GIM realized an accuracy of 0.025 ± 0.2 mm and -0.03 ± 0.25° for push-pull and rotation without delivery resistance. Under < 10 N delivery resistance, the error caused by the airbag stiffness was < 0.24 mm. A quadratic polynomial could be used to describe the relationship between the CSF and pneumatic pressure.

CONCLUSIONS

The novel GIM could effectively deliver gastroscopes. The pneumatic-driven clamping method proposed could protect the gastroscope by circumferentially uniform clamping force and the CSF could be properly controlled to guarantee operating safety. Copyright © 2016 John Wiley & Sons, Ltd.

Endoscopic submucosal dissection

ESD is an established effective treatment modality for premalignant and early-stage malignant lesions of the stomach, esophagus, and colorectum. Compared with EMR, ESD is generally associated with higher rates of en bloc, R0, and curative resections and a lower rate of local recurrence. Oncologic outcomes with ESD compare favorably with competing surgical interventions, and ESD also serves as an excellent T-staging tool to identify noncurative resections that will require further treatment. ESD is technically demanding and has a higher rate of adverse events than most endoscopic procedures including EMR. As such,sufficient training is critical to ensure safe conduct and high-quality resections. A standardized training model for Western endoscopists has not been clearly established,but will be self-directed and include courses, animal model training, and optimally an observership at an expert center.Numerous dedicated ESD devices are now available in the United States from different manufacturers. Although the use of ESD in the United States is increasing, issues related to technical difficulty, limited training opportunities and mentors, risk of adverse events, long procedure duration,and suboptimal reimbursement may limit ESD adoption in the United States to a modest number of academic referral centers for the foreseeable future.

Degree of colonic distension: intrapatient comparison between CT colonography and CT with water enema

PURPOSE

Compare colonic distension using CT colonography (CTC) and CT with water enema (CTWE) in the same patients.

METHODS AND MATERIALS

Twenty-seven patients who underwent both CTC and CTWE, considering separately supine (CTC-S) and prone (CTC-P) acquisition of CTC were included. The colon was divided into six segments, performing both a qualitative and quantitative analysis.

RESULTS

Adequate distension of sigmoid colon was more frequently achieved with CTC-P and CTWE compared to CTC-S (P<.05). CTC-P and CTWE showed better distension of the left colon compared to CTC-S (P<.01 and P=.03 regarding sigmoid colon, respectively; P=.01 and P=.03 regarding descending colon, respectively).

CONCLUSIONS

Computed tomography (CT) studies of the colon should be customized to fulfill the clinical query.

British Society of Gastroenterology/Association of Coloproctologists of Great Britain and Ireland guidelines for the management of large non-pedunculated colorectal polyps

These guidelines provide an evidence-based framework for the management of patients with large non-pedunculated colorectal polyps (LNPCPs), in addition to identifying key performance indicators (KPIs) that permit the audit of quality outcomes. These are areas not previously covered by British Society of Gastroenterology (BSG) Guidelines.A National Institute of Health and Care Excellence (NICE) compliant BSG guideline development process was used throughout and the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool was used to structure the guideline development process. A systematic review of literature was conducted for English language articles up to May 2014 concerning the assessment and management of LNPCPs. Quality of evaluated studies was assessed using the Scottish Intercollegiate Guidelines Network (SIGN) Methodology Checklist System. Proposed recommendation statements were evaluated by each member of the Guideline Development Group (GDG) on a scale from 1 (strongly agree) to 5 (strongly disagree) with >80% agreement required for consensus to be reached. Where consensus was not reached a modified Delphi process was used to re-evaluate and modify proposed statements until consensus was reached or the statement discarded. A round table meeting was subsequently held to finalise recommendations and to evaluate the strength of evidence discussed. The GRADE tool was used to assess the strength of evidence and strength of recommendation for finalised statements.KPIs, a training framework and potential research questions for the management of LNPCPs were also developed. It is hoped that these guidelines will improve the assessment and management of LNPCPs.

Water-Aided Colonoscopy in Inflammatory Bowel Disease Patients-A Randomised, Single-Centre Trial

BACKGROUND

Water-aided colonoscope insertion reduces patients' discomfort and need for sedation in unsedated and minimally sedated patients. However, water-aided technique has never been studied in inflammatory bowel disease patients, characterised by younger age, structural changes of the colon and need for repeated colonoscopies. Our trial was designed to evaluate discomfort associated with water-aided colonoscopy compared with air insufflation in on-demand sedated patients with known inflammatory bowel disease.

METHODS

In a randomised, single-centre study, 92 patients were randomised to either water-aided insertion and air insufflation during withdrawal [Water] or air insufflation during both insertion and withdrawal [Air]. The main outcome measured was success rate of unsedated colonoscopy, defined as reaching the caecum without requiring sedation and with discomfort during insertion of less than or equal to 5 using 0-10 continuous scale [0 = none, 10 = maximum pain].

RESULTS

Success rate of caecal intubation without sedation or invoking a discomfort score greater than 5 was significantly higher in the Water arm compared with the Air arm [73.9 vs 45.7%, p = 0.01]. Discomfort score during insertion [mean ± SD] was significantly lower in the Water than in the Air arm [3.8±2.4 vs 5.4±1.9, p < 0.001]. Other outcomes including procedural times, success rate of terminal ileum intubation, need for abdominal compression, and repositioning were comparable. There were no complications recorded in the study.

CONCLUSIONS

Compared with air insufflation, water-aided colonoscopy significantly reduces discomfort in on-demand sedated patients with inflammatory bowel disease, achieving comparable procedural outcomes.

Perforation of a Long-standing Ileocolonic Anastomosis During Colonoscopy

Colonoscopy is a valuable diagnostic and therapeutic procedure. Colonic perforation is a serious complication of colonoscopy that must be promptly recognized to limit morbidity and mortality. We present a 69-year-old woman who, during colonoscopy, had a perforation secondary to barotrauma of a long-standing ileocolonic anastomosis proximal to the point of colonoscopic intubation. To our knowledge, this is the first case report of a perforation of a well-established anastomosis proximal to the point of endoscope intubation during colonoscopy.

Randomized controlled trial of probiotics after colonoscopy

BACKGROUND

Up to 20% of patients have ongoing abdominal symptoms at day 2 and beyond following colonoscopy. It was hypothesized that some of these symptoms are related to alterations in gut microbiota secondary to bowel preparation and would improve with probiotics compared with placebo.

METHODS

Patients were given either a probiotic or placebo capsule in the days following colonoscopy. Colonoscopy was performed with air insufflation. The probiotic capsule contained the strains Lactobacillus acidophilus NCFM and Bifidobacterium lactis Bi-07. Patients recorded their symptoms at 1 h, 1, 2, 4, 7 and 14 days post colonoscopy and returned results once their symptoms had resolved. The primary outcomes used were the length of days to resolution of bloating, abdominal pain and altered bowel function post colonoscopy.

RESULTS

A total of 320 patients were randomized. After loss to follow-up and withdrawal, 133 patients were analysed in the probiotic group and 126 in the placebo group. Patients having probiotic had a lower number of pain days following colonoscopy, 1.99 versus 2.78 days (P < 0.033). There was no significant difference in bloating or return to normal bowel habit days (P = 0.139 and 0.265 respectively). Subgroup analysis revealed that patients with pre-existing abdominal pain benefited from probiotics in number of pain days, 2.16 versus 4.08 (P = 0.0498).

CONCLUSION

Our study has shown a significant reduction in the duration of pain days post colonoscopy in patients taking probiotic compared with placebo. No significant effect was seen in terms of return to normal bowel function or bloating post colonoscopy.

Endoscopic management of iatrogenic perforations during endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) for colorectal polyps: a case series

BACKGROUND

Iatrogenic perforation during therapeutic colonoscopy, reported in up to 1% of endoscopic mucosal resections (EMRs) and up to 14% of endoscopic submucosal dissections (ESDs), has conventionally been an indication for surgery.

AIMS

We present a case series of successful endoscopic management of iatrogenic colorectal perforation during EMR and ESD, demonstrating the feasibility and safety of the method.

METHODS

Retrospective analysis of a database of patients undergoing EMR and ESD for colorectal polyps in a tertiary referral centre in the United Kingdom.

RESULTS

Four cases of perforation were identified (two EMRs and two ESDs) in a series of 218 procedures (1.8%), all detected at the time of endoscopy and managed with endoscopic clips. Patients were observed in hospital and treated with antibiotics. Their median length of stay was 3 days (range 2-6 days), with no mortality or need for surgery.

CONCLUSION

Surgery is no longer the first choice in the management of iatrogenic perforations during EMR and ESD for colorectal polyps; in selected patients with small perforations and minimal extraluminal contamination, conservative management with application of endoscopic clips, antibiotics and close patient monitoring constitute a safe and effective treatment option, avoiding the morbidity of major surgery.

A randomized, controlled trial comparing real-time insertion pain during colonoscopy confirmed water exchange to be superior to water immersion in enhancing patient comfort

BACKGROUND

A recent American Society for Gastrointestinal Endoscopy Technology Status Evaluation Report recommended comparative studies of water-aided colonoscopy methods to refine the optimal insertion technique.

OBJECTIVE

Air insufflation (AI), water immersion (WI), and water exchange (WE) were compared head-to-head to test the hypothesis that WE produces the least insertion pain.

DESIGN

Patient-blinded, prospective, randomized, controlled trials.

SETTING

Two community hospitals in Italy.

PATIENTS

First-time diagnostic or screening colonoscopy in unsedated patients with the option of on-demand sedation.

INTERVENTION

Colonoscopy with AI, WI, or WE.

MAIN OUTCOME MEASUREMENTS

Real-time maximum insertion pain (0 = none, 10 = worst). To avoid interventional bias, the timing of recording was at the discretion of the nurse assistant. Adjunct measures were implemented to ensure patient perception of minimal discomfort. Recalled pain and patients' guess of insertion methods were recorded after colonoscopy.

RESULTS

Results were merged for 576 randomized patients. Correct patient guesses lower than 33% confirmed adequate blinding. Significant correlation (Pearson coefficient 0.6, P < .0005) between real-time and recalled pain provided internal validation of the former as the primary outcome. Real-time pain (95% confidence interval [CI]: AI, 4.1 [3.7-4.5]; WI, 3.5 [3.0-3.9]; and WE, 2.5 [2.2-2.9] [P < .0005] was the lowest in the WE group. The proportions of patients completing unsedated colonoscopy based on the assigned methods were significantly different (WE, 74.7% vs WI, 62.4%; P = .009; vs AI, 65.3%; P = .04). WE required the least implementation of adjunct maneuvers.

LIMITATIONS

Unblinded colonoscopists.

CONCLUSION

The current findings with an internally validated primary outcome in adequately blinded patients support the hypothesis that WE is superior to WI in attenuating real-time insertion pain and enhancing completion of unsedated colonoscopy.

A patient-blinded randomized, controlled trial comparing air insufflation, water immersion, and water exchange during minimally sedated colonoscopy

OBJECTIVES

Minimal sedation obviates patient recovery burdens, but intolerable pain limits success of cecal intubation. Painless or minimally uncomfortable insertion ensures success of cecal intubation, current patient satisfaction, and willingness to repeat future colonoscopy with minimal sedation. Water immersion (WI) and water exchange (WE), when separately compared with air insufflation (AI), significantly reduced insertion pain. To assess comparative effectiveness, we conducted a randomized controlled trial with head-to-head comparison of these three methods. We hypothesized that WE could produce the highest proportion of patients reporting painless insertion.

METHODS

This prospective patient-blinded trial (NCT01535326) enrolled minimally sedated (25 mg intramuscular meperidine) patients randomized to AI, WI, or WE (90 patients/group) to aid insertion. The previously validated primary outcome was the proportion of patients reporting painless insertion.

RESULTS

Painless insertion was reported by 30.0% (AI), 43.3% (WI), and 61.1% (WE) of patients (P<0.001). Multivariate logistic regression analysis revealed that, after adjusting for gender, body mass index, abdominal compression, position change, insertion time to cecum, and length of scope at cecum, only WE was significantly associated with painless insertion compared with AI (odds ratio (OR)=0.08, 95% confidence interval (CI)=0.03-0.24, P<0.001) or WI (OR=0.14, 95% CI=0.05-0.40, P<0.001). Adenoma detection rate (ADR) in the right (cecum and ascending) colon was 11.1% (AI), 14.4% (WI), and 26.7% (WE) (P=0.015). The limitations included single site study with unblinded colonoscopist and assistant.

CONCLUSIONS

This head-to-head comparison of AI vs. WI vs. WE confirmed that WE was superior to WI and AI, with a significantly greater proportion of patients reporting painless insertion. The significantly higher ADR in the right colon in the WE group warrants further investigations.

Impact of water exchange colonoscopy on serum sodium and potassium levels: an observational study

BACKGROUND

Concerns over the hypothetical adverse effects of water absorption and the disturbance of serum sodium and potassium levels prompted a quality assurance evaluation of water exchange (WE) colonoscopy.

AIM

The purpose of this study was to evaluate the balance of water infused and suctioned in WE colonoscopy, and to quantify the acute impact on serum levels of sodium and potassium.

METHODS

Prospectively collected quality monitoring data of patients undergoing screening and surveillance colonoscopy at the Sacramento Veterans Affairs Medical Center were analyzed. Measurements were made of volume infused and suctioned during, and blood samples drawn 10 min before the start of and 10 min after completion of WE colonoscopy. Outcome measures included volume of water infused and suctioned, and serum levels of sodium and potassium.

RESULTS

A total of 140 patients (134M:6F), mean age of 59, underwent WE colonoscopy. Mean total volume of water infused was 1,839 mL. A negative balance of an average of 22 mL was documented. The mean (standard deviation) values (in meq/L) of serum levels of sodium 139.33 (2.27) and 139.28 (2.32), and potassium 3.86 (0.36) and 3.91 (0.39), before and after colonoscopy, respectively, showed no significant change.

CONCLUSION

The WE method allowed most of the water infused during colonoscopy to be recovered by suction at the completion of colonoscopy. Serum sodium and potassium levels did not change significantly within 10 min after completion. The WE method appears to be safe with minimal water retention and is devoid of acute fluctuations in serum levels of sodium and potassium.