NORCCAP (Norwegian colorectal cancer prevention): a randomised trial to assess the safety and efficacy of carbon dioxide versus air insufflation in colonoscopy

Carbon dioxide insufflation reduces the relapse of ulcerative colitis after colonoscopy: A randomized controlled trial

BACKGROUND AND AIM

Colonoscopy is necessary for diagnosing and surveilling patients with ulcerative colitis, though it may cause disease flares. Colonoscopy with carbon dioxide (CO2) insufflation decreases abdominal discomfort; however, its effect on exacerbation incidence in ulcerative colitis remains unclear. Therefore, this study aimed to evaluate the colonoscopy effects using CO2 insufflation in patients with ulcerative colitis.

METHODS

Overall, 96 remissive patients with ulcerative colitis (partial Mayo score ≤ 2) who underwent total colonoscopy between March 2015 and December 2019 at Osaka University Hospital were enrolled and blindly randomized to the CO2 (n = 45) and air (n = 51) insufflation group (UMIN-CTR, number: UMIN000018801). The post-procedural abdominal discomfort and the clinical relapse (partial Mayo score ≥ 3) rate within 8 weeks were evaluated.

RESULTS

Baseline backgrounds did not differ between the groups. The mean abdominal fullness and pain scores were significantly lower in the CO2 group than in the Air group immediately (p = 0.0003, p = 0.0003) and 30 min (p < 0.0001, p < 0.0001) after colonoscopy. While the overall clinical relapse rate remained unchanged between the groups, the clinical relapse rate at 8 weeks after colonoscopy was significantly lower in the CO2 group than in the Air group in patients not in complete remission (Mayo endoscopic subscore ≥ 1, p = 0.049; or partial Mayo score ≥ 1, p = 0.022).

CONCLUSIONS

CO2 insufflation can reduce abdominal discomfort in remissive patients with ulcerative colitis and decrease clinical relapse at 8 weeks after colonoscopy for those not in complete remission.

Long-term follow-up of colorectal cancer screening attendees identifies differences in Phascolarctobacterium spp. using 16S rRNA and metagenome sequencing

Background

The microbiome has been implicated in the initiation and progression of colorectal cancer (CRC) in cross-sectional studies. However, there is a lack of studies using prospectively collected samples.

Methods

From the Norwegian Colorectal Cancer Prevention (NORCCAP) trial, we analyzed 144 archived fecal samples from participants who were diagnosed with CRC or high-risk adenoma (HRA) at screening and from participants who remained cancer-free during 17 years of follow-up. We performed 16S rRNA sequencing of all the samples and metagenome sequencing on a subset of 47 samples. Differences in taxonomy and gene content between outcome groups were assessed for alpha and beta diversity and differential abundance.

Results

Diversity and composition analyses showed no significant differences between CRC, HRA, and healthy controls. Phascolarctobacterium succinatutens was more abundant in CRC compared with healthy controls in both the 16S and metagenome data. The abundance of Bifidobacterium and Lachnospiraceae spp. was associated with time to CRC diagnosis.

Conclusion

Using a longitudinal study design, we identified three taxa as being potentially associated with CRC. These should be the focus of further studies of microbial changes occurring prior to CRC diagnosis.

VOLUMETRIC CAPNOGRAPHY FOR RESPIRATORY MONITORING OF PATIENTS DURING ROUTINE COLONOSCOPY WITH ROOM-AIR AND CARBON DIOXIDE INSUFFLATION

BACKGROUND

Capnography and carbon dioxide (CO2) insufflation during gastrointestinal endoscopy under sedation are associated with safety and comfort improvements, respectively. Capnography can provide early detection of apnea and hypoxemia, whereas CO2 insufflation causes lower periprocedural discomfort. This is the first study to report the application of volumetric capnography in colonoscopy.

OBJECTIVE

This study aimed to evaluate the use of volumetric capnography with room air (RA) and CO2 insufflation during routine colonoscopy.

METHODS

In this prospective cohort study, 101 patients who underwent routine colonoscopy under sedation with volumetric capnography monitoring were included. Insufflation with RA was used to distend the intestinal lumen in group 1 (n=51), while group 2 (n=50) used CO2 insufflation. The primary endpoints were episodes of hypoxia, alveolar hypoventilation, and end-tidal CO2 (EtCO2). The secondary endpoints were tidal volume per minute, consumption of sedation medications, and post-procedure pain using the Gloucester modified pain scale.

RESULTS

The number of episodes of hypoxia (SpO2<90%) was similar between the groups: four episodes in Group 1 and two episodes in Group 2. The duration of hypoxia was significantly longer in group 2 (P=0.02). Hypoalveolar ventilation (EtCO2) occurred more frequently in Group 2 than in Group 1 (27 vs 18 episodes, P=0.05). Regarding EtCO2, Group 2 showed higher values in cecal evaluation (28.94±4.68 mmHg vs 26.65±6.12 mmHg, P=0.04). Regarding tidal volume per minute, Group 2 had significantly lower values at the cecal interval compared to Group 1 (2027.53±2818.89 vs 970.88±1840.25 L/min, P=0.009). No episodes of hypercapnia (EtCO2 > 60 mmHg) occurred during the study. There was no difference in the consumption of sedation medications between the groups. Immediately after colonoscopy, Group 2 reported significantly less pain than Group 1 (P=0.05).

CONCLUSION

In our study, volumetric capnography during colonoscopy was feasible and effective for monitoring ventilatory parameters and detecting respiratory complications. CO2 insufflation was safe and associated with less pain immediately after colonoscopy.

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.

Relief Effect of Carbon Dioxide Insufflation in Transnasal Endoscopy for Health Checks-A Prospective, Double-Blind, Case-Control Trial

CO2 insufflation has proven effective in reducing patients’ pain after colonoscopies but has not been examined in esophagogastroduodenoscopies. Therefore, we examined the effect of CO2 insufflation in examinees who underwent transnasal endoscopies without sedation. This study is a single-center, prospective, double-blind, case-control trial conducted between March 2017 and August 2018. Subjects were assigned weekly to receive insufflation with either CO2 or air. The primary outcome was improvement of abdominal pain and distension at 2 h and 1-day postprocedure. In total, 336 and 338 examinees were assigned to the CO2 and air groups, respectively. Visual analog scale (VAS) scores for abdominal distension (15.4 vs. 25.5; p < 0.001) and distress from flatus (16.0 vs. 28.8; p < 0.001) at 2 h postprocedure were significantly reduced in the CO2 group. VAS scores for pain during the procedure (33.5 vs. 37.1; p = 0.059) and abdominal pain after the procedure (3.9 vs. 5.7; p = 0.052) also tended to be lower at 2 h postprocedure, but all parameters showed no significant difference at 1-day postprocedure. All procedures were safely completed through the planned program, and no apparent adverse events requiring treatment or follow-up occurred. In conclusion, CO2 insufflation may reduce postprocedural abdominal discomfort from transnasal esophagogastroduodenoscopies. (UMIN000028543).

WASh multicentre randomised controlled trial: water-assisted sigmoidoscopy in English NHS bowel scope screening

OBJECTIVES

The English Bowel Cancer Screening Programme invites 55 year olds for a sigmoidoscopy (Bowel Scope Screening (BSS)), aiming to resect premalignant polyps, thus reducing cancer incidence. A national patient survey indicated higher procedural pain than anticipated, potentially impacting on screening compliance and effectiveness. We aimed to assess whether water-assisted sigmoidoscopy (WAS), as opposed to standard CO₂ technique, improved procedural pain and detection of adenomatous polyps.

DESIGN

The WASh (Water-Assisted Sigmoidoscopy) trial was a multicentre, single-blind, randomised control trial for people undergoing BSS. Participants were randomised to either receive WAS or CO₂ from five sites across England. The primary outcome measure was patient-reported moderate/severe pain, as assessed by patients on a standard Likert scale post procedure prior to discharge. The key secondary outcome was adenoma detection rate (ADR). The costs of each technique were also measured.

RESULTS

1123 participants (50% women, mean age 55) were randomised (561 WAS, 562 CO₂). We found no difference in patient-reported moderate/severe pain between WAS and CO₂ (14% in WAS, 15% in CO2; p=0.47). ADR was 15% in the CO₂ arm and 11% in the WAS arm (p=0.03); however, it remained above the minimum national performance standard in both arms. There was no statistical difference in mean number of adenomas nor overall polyp detection rate. There was negligible cost difference between the two techniques.

CONCLUSION

In the context of enema-prepared unsedated screening sigmoidoscopies performed by screening-accredited endoscopists, no difference in patient-reported pain was seen when using either a CO₂ or WAS intubation technique.

TRIAL REGISTRATION NUMBER

ISRCTN81466870.

Carbon Dioxide vs. Air Insufflation for Pediatric Gastrointestinal Endoscopy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Carbon dioxide (CO₂) insufflation during gastrointestinal (GI) endoscopic procedures has gained popularity in adults. However, its utility in pediatric patients is not known. The current review aimed to compare the efficacy of CO₂ vs. air insufflation for GI endoscopic procedures in pediatric patients. Methods: The electronic databases of PubMed, Embase, Scopus, and CENTRAL were searched from the inception of databases to 15th August 2020. Results: All randomized controlled trials (RCTs) comparing CO₂ vs. air insufflation for GI endoscopic procedures in pediatric patients were eligible for inclusion. Five RCTs were identified. Pooled analysis of data from 226 patients in the CO₂ group and 224 patients in the air group revealed that patients receiving CO₂ insufflation were at a lower odds of experiencing postoperative pain as compared to those undergoing the procedure with air (OR: 0.40; 95% CI: 0.19, 0.87; I ² = 62%; p = 0.02). Descriptive analysis indicated no difference in the two groups for abdominal distention after the procedure. Two trials reported elevated CO₂ in the study group but without any pulmonary complications. Bloating was reported by two studies and both reported significantly less bloating in the CO₂ group. Conclusion: Our study indicates that the incidence of pain may be reduced with the use of CO₂ insufflation in pediatric GI endoscopies without a significant risk of adverse events. However, current evidence is from a limited number of trials and not strong to recommend a routine of CO₂ in pediatric gastroenterology practice. Further high-quality RCTs are required to supplement current evidence.

Effect of carbon dioxide versus room air insufflation on post-colonoscopic pain: A prospective, randomized, controlled study

BACKGROUND/AIMS

Room air (RA) and carbon dioxide (CO2) are widely used to insufflate the colon to examine the mucosa in colonoscopy. Pain, discomfort, and bloating can be seen during and after colonoscopy secondary to bowel distention. This study aimed to investigate the effect of CO2 on post-procedure pain sensation (PPPS) in comparison with RA.

MATERIALS AND METHODS

Patients were randomly assigned to the RA and CO2 insufflation groups in a 1:1 ratio. The visual analog scale (VAS) was used to measure the pain before and after the colonoscopy. VAS score of 0 was accepted as the absence of pain and above 0 was accepted as the presence of pain. The primary outcome was to investigate the effect of CO2 insufflation on PPPS. Secondary outcomes were to investigate the other contributing factors affecting PPPS and the effect of CO2 on PPPS in patients with inflammatory bowel disease (IBD).

RESULTS

A total of 204 patients were enrolled in the study. No significant difference in PPPS was seen between the 2 groups at any point in time after the colonoscopy. Furthermore, there was no significant difference in pain sensation between the CO2 and RA groups in patients with IBD. When we investigated the other contributing factors to pain sensation, body-mass index (BMI) was found to be significant at 30 minutes and BMI and colonoscopy time were found to be significant at 6 hours afterwards.

CONCLUSION

We found no favorable effect of CO2 insufflation on PPPS in colonoscopy, including in patients with IBD.

Safety of chronic obstructive pulmonary disease patients undergoing carbon dioxide insufflation in extended endoscopic procedures

Introduction:

Carbon dioxide (CO₂) insufflation for endoscopies has been shown to be more comfortable and safe, but only in patients without underlying chronic obstructive pulmonary disease (COPD). The aim of this study was to show that using CO₂ is safe in COPD patients.

Methods:

Patients were retrospectively identified who underwent extended endoscopic procedures during the time period of January 2012 to December 2017. Patients were included if they also had COPD. A matched control group without COPD was created during the same timeframe. All the patients were sedated with continuous monitoring of their CO₂ levels by end-tidal CO₂ (EtCO₂).

Results:

One hundred and ten patients had COPD and underwent an extended endoscopic procedure. These patients had a higher severity of their comorbidities (American Society of Anesthesiologists class 3 or 4) (93.6% [95% confidence interval [CI], 87.4%–96.9%] vs. 60.3% [95% CI, 51.1%–69.0%]; P < 0.01) and an increase of co-existing obstructive sleep apnea (33.6% vs. 6.3%, P < 0.01). There was no difference in baseline EtCO₂, but the peak EtCO₂ and postprocedure EtCO₂ were both significantly higher in the COPD group. The only postprocedural complication found was an inability to be extubated immediately following the procedure with subsequent need to hospitalize the patient, which occurred in three patients (2.8%; 95% CI, 0.9%–7.9%) in the COPD group and one (0.9%; 95% CI, 0.2%–4.9%) in the non-COPD group (P = 0.37).

Conclusion:

The present study, which was the only study looking at CO₂ insufflation specifically in COPD patients, provides evidence that CO₂ insufflation is safe in COPD despite a slight increase in EtCO₂.

Efficacy and Safety of Carbon Dioxide Versus Air Insufflation for Colonoscopy in Deeply Sedated Pediatric Patients

OBJECTIVES

Studies have shown the advantages of carbon dioxide (CO2) over air insufflation in the adult population during colonoscopies. This study was designed to investigate the efficacy and safety of CO2 insufflation in deeply sedated children undergoing colonoscopy.

METHODS

This was a prospective, randomized, double-blind clinical trial. We recruited 100 consecutive pediatric patients who had colonoscopy under deep sedation for various indications. Patients were first randomized by history of abdominal pain and then randomly assigned to either CO2 or air insufflation. Postprocedural abdominal pain scores were registered on a 10-point visual analog rating scale and significant pain was defined as a score of 3 or higher. Abdominal circumferences and end tidal CO2 (ETCO2) levels were measured. Complications during and after the procedure were recorded.

RESULTS

We did not find statistically significant difference between CO2 and air insufflation on univariate analysis because of low number of children experiencing significant pain after colonoscopy. After adjusting for baseline pain, we found that pain was significantly lower in patients after CO2 versus air insufflation on multivariable analysis (P = 0.03). The significant factors related to pain were duration of the procedure (P = 0.006), history of abdominal pain (P = 0.002) and previous abdominal surgery (P = 0.02). CO2 insufflation was associated with decreased abdominal circumference after colonoscopy (P = 0.002). Girls were more likely to have pain regardless of intervention (P = .04).

CONCLUSIONS

Most children tolerate endoscopic procedures without significant pain. Our study was underpowered to show significant difference between air and CO2 on univariate analysis. CO2 insufflation during colonoscopy, however, may reduce postprocedural abdominal pain. Significant factors for increased pain on multivariate analysis included colonoscopy length over 30 minutes, history of abdominal pain, and previous abdominal surgery.

Bowel Preparation With Polyethylene Glycol 3350 or Fasting Only Before Peroral Single-balloon Enteroscopy: A Randomized European Multicenter Trial

BACKGROUND

Although bowel preparation before colonoscopy and capsule endoscopy is widely evaluated and usually follows established guidelines, a standard preparation regime for peroral small bowel enteroscopy is yet to be defined.The aim of the present study was to compare small bowel preparation with polyethylene glycol (PEG) and "fasting only" (FO) before peroral single-balloon enteroscopy (SBE).

STUDY

We compared small bowel preparation with PEG versus "FO" for peroral SBE in a randomized European multicenter trial. Patients' and procedural characteristics were documented and carefully analyzed. Primary endpoint was the oral intubation depth of the small bowel. A modified Boston preparation scale was used to assess bowel cleansing as a secondary endpoint.

RESULTS

In total, 43 patients were enrolled in this study (FO group: n=25; PEG group: n=18). In both groups, patients' characteristics were comparable. The indications for oral enteroscopy were equally distributed in both groups (P=0.894). The oral intubation depth was significantly higher in the PEG versus the FO group (261±87 vs. 203±66 cm; P=0.019; mean±SD), while the quality of bowel preparation was equally sufficient in both groups [complete visualization of the mucosa (Boston preparation scale) 83% versus 76% (P=1.000)].

CONCLUSIONS

Small bowel preparation with PEG for SBE yields significantly deeper intubation as compared with "FO" preparation. As patient comfort and safety was similar in both groups, PEG preparation might be favored, especially if deep intubation of the small bowel is desired. For patients requiring visualization of the proximal jejunum, a FO preparation seems to be sufficient.

Transcutaneous partial pressure of carbon dioxide monitoring during EUS-guided drainage of peripancreatic fluid collections using carbon dioxide insufflation: A prospective study

Background:

Carbon dioxide (CO₂) insufflation has become more commonly used in EUS-guided interventions in recent years. However, there is a paucity of information regarding methods by which to monitor in vivo CO₂ levels. This study aimed to assess the feasibility of a novel noninvasive method to monitor transcutaneous partial pressure of CO₂ (P_CO2) (P_tcCO2) levels during EUS-guided drainage of peripancreatic fluid collections (PFCs). The safety of CO₂ insufflation in EUS-guided interventions was also investigated.

Patients and Methods:

Patients who underwent EUS-guided PFC drainage between September 2015 and December 2016 at Shengjing Hospital of China Medical University were prospectively enrolled in this study. P_tcCO2 was measured in all patients using a noninvasive sensor throughout the procedure.

Results:

There were 25 patients eligible to be included in this study. The mean procedure time was 53.1 min. The mean P_tcCO2 level was 40 ± 4 mmHg and 48 ± 5 mmHg before and after the procedure, respectively. The mean peak P_tcCO2 during the procedure was significantly higher at 53 ± 6 mmHg (P < 0.0001). No complications associated with CO₂ insufflation such as CO₂ narcosis, gas embolism, or arrhythmias were encountered.

Conclusions:

P_tcCO2 monitoring can accurately reflect the level of P_CO2 continuously and noninvasively. CO₂ insufflation is safe for patients undergoing relatively complicated EUS-guided drainage of PFCs.

Carbon dioxide versus room air for colonoscopy in deeply sedated pediatric patients: a randomized controlled trial

Background and study aims  Use of carbon dioxide (CO ₂ ) instead of room air (RA) during colonoscopy in adults revealed significantly less flatulence and abdominal pain in several studies. The objectives of this study were to investigate the effects of CO ₂ usage on post-interventional pain, abdominal discomfort, abdominal girth, pCO ₂ levels, and narcotic requirement in deeply sedated pediatric patients. Patients and methods  A total of 97 children and adolescents aged 4 years to 17 years undergoing colonoscopy were randomized to RA or CO ₂ in a prospective, randomized, controlled trial. Age-appropriate pain scales assessed abdominal pain as primary outcome. In addition, abdominal girth, abdominal bloating, transcutaneous pCO ₂ , narcotic requirement to achieve deeply sedation, and post-procedural analgesic demand was analyzed in 73 patients. Results  Overall, significantly fewer patients reported bloating in the CO ₂ group ( P  = 0.0012). However, we observed only a trend to lower post-interventional pain ( P  = 0.15) and a lower pain score. There was no significant difference in transcutaneous pCO ₂ level and no adverse events occurred. Although there was no difference in the dosage of propofol and midazolam, we observed a significant increased necessity for use of synthetic opioids in the RA group to achieve optimal examination conditions ( P  = 0.023). Conclusions  The benefits using CO ₂ in colonoscopy of deeply sedated children predominate. In particular, CO ₂ insufflation may allow a less painful post-interventional time and it significantly reduces abdominal bloating. Moreover, with CO ₂ , significantly less additional opioids were used. Thus, CO ₂ insufflation can be considered as safe in deeply sedated patients as there was no relevant pulmonary CO ₂ retention observed. (DRKS00013914).

Carbon Dioxide Insufflation Increases Colonoscopic Adenoma Detection Rate Compared With Air Insufflation

GOALS

To determine the effect of carbon dioxide insufflation on the most important outcome measure of colonoscopic quality: adenoma detection rate (ADR).

BACKGROUND

Bowel cancer is the second most common cause of cancer deaths in males and females in Australia. Carbon dioxide has in recent times become the insufflation methodology of choice for screening colonoscopy for bowel cancer, as this has been shown to have significant advantages when compared with traditional air insufflation.

STUDY

Endoscopies performed over a period of 9 months immediately before and after the implementation of carbon dioxide insufflation at endoscopy centers were eligible for inclusion.

RESULTS

The difference in ADR between the carbon dioxide and air insufflation methods was statistically significant, with an increased ADR in the carbon dioxide group. The superiority of carbon dioxide insufflation was sustained with a logistic regression model, which showed ADR was significantly impacted by insufflation method.

CONCLUSIONS

Carbon dioxide insufflation is known to reduce abdominal pain, postprocedural duration of abdominal pain, abdominal distension, and analgesic requirements. This study represents for the first time the beneficial effect of carbon dioxide insufflation upon the key quality colonoscopy indicator of ADR.

Insufflation With Carbon Dioxide During Pediatric Colonoscopy for Control of Postprocedure Pain

GOALS

To determine if carbon dioxide (CO2) insufflation in children would improve postprocedure pain following colonoscopy in children.

BACKGROUND

CO2 insufflation during colonoscopy has been found to reduce postcolonoscopy pain in the adult population, but limited data exist in pediatrics.

MATERIALS AND METHODS

We conducted a prospective study with 40 pediatric patients scheduled for outpatient colonoscopy. Patients were enrolled continuously and were randomized to receive CO2 or air insufflation. Patients and colonoscopists were blinded to insufflation method. End tidal CO2 (EtCO2) was documented throughout the procedure. Abdominal pain was established preprocedure then at 1-, 6-, and 24-hour postprocedure. Subject demographics, indications, colonoscopists' year of training, time to cecum, adverse events, and final diagnoses were recorded.

RESULTS

Twenty patients were randomized to each group. Patients receiving air had a statistically significant increase in pain from baseline at 1- and 6-hours after colonoscopy (P=0.007 and 0.008). This was not seen in the CO2 group (P=0.740 and 0.289). There was an increase in postprocedure pain in the air group compared with CO2 group at the 1-hour mark (P=0.032). EtCO2 increased during the procedure, regardless of insufflation method, but no difference was seen between groups (P=0.822).

CONCLUSIONS

Our results demonstrate that higher levels of pain were reported by patients following air compared with those receiving CO2 insufflation. This is the first study to show CO2 is as safe as air, with no increase in EtCO2 between groups in the pediatric population. CO2 is an effective and safe modality and should be considered for pediatric colonoscopies.

Ectopic air localizations after transanal procedures: A systematic literature review

BACKGROUND

Aim of this study is to report and to analyze the incidence, clinical impact and treatment options of ectopic air localizations after transanal procedures.

METHODS

A systematic literature review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The research was carried out using the PubMed database, identifying 40 articles with the following keywords: "transanal" AND "emphysema"; "transanal" AND "subcutaneous emphysema"; "transanal" AND "pneumomediastinum"; "transanal" AND "pneumothoraces"; "transanal" AND "pneumopericardium"; "transanal" AND "retropneumoperitoneum".

RESULTS

Nineteen articles, published between 1993 and 2017, were included in the study for a total of 29 patients. The most frequent air localization was in the retroperitoneum, followed by subcutaneous tissues, mediastinum and neck. This condition was treated conservatively in 20 patients, with colostomy in 4 patients, with bowel resection and negative diagnostic laparoscopy in one patient each. In three cases the treatment was not specified. Ectopic air location resolved in all cases.

CONCLUSIONS

Pneumo-mediastinum and pneumo-retroperitoneum after transanal procedures are unusual complications with a dramatic radiological appearance but can be managed successfully with a completely benign course in most cases. Initially, a conservative approach is recommended. Surgical treatment should be reserved only in case of fluid collection or suture dehiscence.

Carbon dioxide versus air insufflation enteroscopy: a systematic review and meta-analysis based on randomized controlled trials

OBJECTIVES

 To compare the insufflation of CO ₂ and ambient air in enteroscopy.

SEARCH SOURCES

 The investigators researched the electronic databases MedLine, Cochrane Library, Central, LILACS, BVS, Scopus and Cinahl. The grey search was conducted in the base of theses of the University of São Paulo, books of digestive endoscopy and references of selected articles and in previous systematic revisions.

STUDY ELIGIBILITY CRITERIA

 The evaluation of eligibility was performed independently, in a non-blind manner, by two reviewers, firstly by title and abstract, followed by complete text. Disagreements between the reviewers were resolved by consensus.

DATA COLLECTION AND ANALYSIS METHOD

 Through the spreadsheet of data extraction, where one author extracted the data and a second author checked the extraction. Disagreements were resolved by debate between the two reviewers. The quality analysis of the studies was performed using the Jadad score. The software RevMan 5 version 5.3 was used for the meta-analysis.

RESULTS

 Four randomized clinical trials were identified, totaling 473 patients submitted to enteroscopy and comparing insufflation of CO ₂ and ambient air. There was no statistical difference in the intubation depth between the two groups. When CO ₂ insufflation was reduced, there was a significant difference in pain levels 1 hour after the procedure (95 % IC, -2.49 [-4.72, -0.26], P : 0.03, I ² : 20%) and 3 hours after the procedure (95% IC, -3.05 [-5.92, -0.18], P : 0.04, I ² : 0 %). There was a usage of lower propofol dosage in the CO ₂ insufflation group, with significant difference (95 % IC, -67.68 [-115.53, -19.84], P : 0.006, I ² : 0 %). There was no significant difference between the groups in relation to the use of pethidine and to the oxygen saturation.

LIMITATIONS

 Restricted number of randomized clinical trials and nonuniformity of data were limitations to the analysis of the outcomes.

CONCLUSION

 The use of CO ₂ as insufflation gas in enteroscopy reduces the pain levels 1 hour and 3 hours after the procedure, in addition to the reduction of the sedation (propofol) dosage used.

Carbon dioxide insufflation during endoscopic resection of large colorectal polyps can reduce post-procedure abdominal pain: A prospective, double-blind, randomized controlled trial

Background

Studies of the use of CO₂ insufflation during endoscopic resection of large colorectal polyps (LCPs) are lacking.

Objective

We evaluated the effect of CO₂ insufflation on pain after endoscopic resection of LCPs.

Methods

In a prospective randomized controlled trial (RCT), 132 patients were randomly assigned to groups who underwent endoscopic resection with CO₂ insufflation (CO₂ group, n = 66) or air insufflation (air group, n = 66). The primary outcome was abdominal pain post-procedure (PP). The secondary outcomes were abdominal distension, rates of technical success, amounts of sedatives prescribed, use of analgesics, and adverse events.

Results

Baseline patient characteristics were similar between the groups. The mean abdominal pain score was 12.3 in the CO₂ group vs. 17.5 in the air group at 1 h PP (p  =  0.047). Also, the proportion of patients without pain was significantly higher in the CO₂ group at 1 h PP (p = 0.008). The pain score differed more in the endoscopic submucosal dissection group and long-time group. The secondary outcomes were not significantly different between the two groups.

Conclusions

The results of this RCT demonstrate the superiority of CO₂ insufflation for endoscopic resection of LCPs in terms of decreasing PP abdominal pain (KCT0001636).

Bayesian network meta-analysis: Efficacy of air insufflation, CO2 insufflation, water exchange, and water immersion in colonoscopy

BACKGROUND AND AIM

Colonoscopy is an excellent screening tool for colorectal cancer. There are four colonoscopy techniques: air insufflation, CO₂ insufflation, water exchange, and water immersion. Some studies reported that the latter three methods are better than the criterion standard (air insufflation), whereas some studies did not. In order to evaluate the efficacy of the four colonoscopy techniques, a network meta-analysis was carried out.

METHODS

We searched randomized controlled trials (RCT) published up to September 2017 from PubMed, Embase, Cochrane library, and Web of Science. Studies referencing the comparison between at least two of air insufflation, CO₂ insufflation, water exchange, and water immersion were selected. Primary outcomes included pain score during insertion, polyp detection rate, and adenoma detection rate, and secondary outcomes included cecal intubation time and cecal intubation rate. Mean differences or odds ratios and their corresponding 95% credible intervals were pooled with Bayesian modeling.

RESULTS

Forty RCT with 13 734 patients were included in this network meta-analysis. Our analysis showed that air insufflation had the highest pain score (surface under the cumulative ranking curve [SUCRA]: 98.8%) and the lowest detection rate of adenoma (SUCRA: 21.3%) and polyp (SUCRA: 16.8%). Water exchange had the lowest pain score (SUCRA: 1.1%) and highest detection rate of adenoma (SUCRA: 96.0%) and polyp (SUCRA: 98.9%), although it led to the longest cecal intubation time (SUCRA: 86.9%).

CONCLUSIONS

Air insufflation might be the most unsatisfactory colonoscopy. Meanwhile, water exchange might be the most efficient colonoscopy.

Feasibility and Importance of Enteroscopy after Gastric Bypass

BACKGROUND

Bariatric surgery has increased in popularity, with Roux-en-Y Gastric Bypass (RYGB) being one of the most frequently performed. This leads to many cases in which the stomach is removed from routine gastroscopy access, sometimes being a major source of concern. Performing enteroscopy in these patients is technically difficult. We present our experience with 24 cases in which the aim was to access the detached stomach.

METHODS

Retrospective analysis on RYGB enteroscopy procedures aimed to access the detached stomach. Data recorded: demographic parameters, indication, gas insufflation, time to bypass stomach, total procedure and recovery times, and endoscopic and pathological findings.

RESULTS

This study included 24 patients who underwent RYGB in the previous 3-36 months. Indications were chronic abdominal pain, refractory anemia, or unexplainable weight loss. Detached stomach was accessed in 79% of patients. Access time ranged from 25 to 55 min. Recovery time for all procedures was 86.66 min on average and shorter with CO₂ insufflation (42.5 min). All detached stomachs showed macroscopic gastritis; four of them were Helicobacter pylori positive. Significant findings included three patients with jejunojejunostomy stenosis and one patient with a marginal gastrojejunal ulcer, which was later diagnosed with Signet ring cell carcinoma of the proximal anastomosis.

CONCLUSIONS

We present the feasibility and importance of enteroscopy of the detached stomach and believe that this procedure should be performed more frequently. A high index of suspicion is needed for postoperative symptoms in order to exclude significant pathologies and reassure symptomatic patients that there is no abnormality in the bypassed stomach.

COLONOSCOPY: RANDOMIZED COMPARATIVE STUDY OF INSUFFLATION WITH CARBON DIOXIDE VERSUS AIR

Background:

In Brazil, an increasing number of people are submitted to colonoscopy, either for screening or for therapeutic purposes.

Aim:

To evaluate whether there are advantages of using carbon dioxide (CO₂) over air for insufflation.

Methods:

Two hundred and ten of 219 patients were considered eligible for this study and were randomized into two groups according to the gas insufflation used: Air Group (n=104) and CO₂ Group (n=97). The study employed a double-blind design.

Results:

The Air and CO₂ Groups were similar in respect to bowel preparation evaluated using the Boston scale, age, gender, previous surgery, maneuvers necessary for the advancement of the device, and presence of polyps, tumors or signs of diverticulitis. However, “waking up with pain” and “pain at discharge” were more prevalent in the Air Group, albeit not statistically significant, with post-exam bloating seen only in the Air Group. The responses to a questionnaire, applied to analyze the late post-exam period, showed more comfort with the use of CO₂.

Conclusions:

The use of CO₂ is better than air as it avoids post-examination bloating, thereby providing greater comfort to patients.

Comparison of carbon dioxide and air insufflation during consecutive EGD and colonoscopy in moderate-sedation patients: a prospective, double-blind, randomized controlled trial

BACKGROUND AND AIMS

Endoscopy is performed with air insufflation and is usually associated with abdominal pain. It is well recognized that carbon dioxide (CO₂) is absorbed more quickly into the body than air; however, to date, few studies have investigated the use of CO₂ insufflation during consecutive EGD and colonoscopy (CEC). Thus, this study evaluated the efficacy of CO₂ insufflation compared with air insufflation in CEC.

METHODS

From March 2014 to April 2016, a total of 215 consecutive patients were randomly assigned to receive CO₂ insufflation (CO₂ group, n = 108) or air insufflation (air group, n = 107). Abdominal pain after CEC was recorded on a visual analogue scale (VAS). The amount of sedatives administered, use of analgesics, polyp detection rate (PDR), adenoma detection rate (ADR), abdominal circumference, and adverse events were also analyzed.

RESULTS

Baseline patient characteristics were not significantly different between the groups. Abdominal pain on the VAS in the CO₂ group and air group 1 hour after CEC was, respectively, 13.8 and 20.1 (P = .010), 3 hours after CEC was 8.3 and 12.5 (P = .056), 6 hours after CEC was 3.5 and 5.3 (P = .246), and 1 day after CEC was 1.8 and 3.4 (P = .192). The dose of sedative administered, analgesic usage, PDR, ADR, and adverse events were not statistically different between the groups. However, the increase in abdominal circumference was significantly higher in the air group than in the CO₂ group.

CONCLUSIONS

CO₂ insufflation was superior to air insufflation with regard to the pain score on the VAS in the hour after CEC. (Clinical trial registration number: KCT0001491.).

CO2 insufflation versus air insufflation for endoscopic submucosal dissection: A meta-analysis of randomized controlled trials

Background

Carbon dioxide (CO₂) insufflation is increasingly used for endoscopic submucosal dissection (ESD) owing to the faster absorption of CO₂ as compared to that of air. Studies comparing CO₂ insufflation and air insufflation have reported conflicting results.

Objectives

This meta-analysis is aimed to assess the efficacy and safety of use of CO₂ insufflation for ESD.

Methods

Clinical trials of CO₂ insufflation versus air insufflation for ESD were searched in PubMed, Embase, the Cochrane Library and Chinese Biomedical Literature Database. We performed a meta-analysis of all randomized controlled trials (RCTs).

Results

Eleven studies which compared the use of CO₂ insufflation and air insufflation, with a combined study population of 1026 patients, were included in the meta-analysis (n = 506 for CO₂ insufflation; n = 522 for air insufflation). Abdominal pain and VAS scores at 6h and 24h post-procedure in the CO₂ insufflation group were significantly lower than those in the air insufflation group, but not at 1h and 3h after ESD. The percentage of patients who experienced pain 1h and 24h post-procedure was obviously decreased. Use of CO₂ insufflation was associated with lower VAS scores for abdominal distention at 1h after ESD, but not at 24h after ESD. However, no significant differences were observed with respect to postoperative transcutaneous partial pressure carbon dioxide (PtcCO₂), arterial blood carbon dioxide partial pressure (PaCO₂), oxygen saturation (SpO₂%), abdominal circumference, hospital stay, white blood cell (WBC) counts, C-Reactive protein (CRP) level, dosage of sedatives used, incidence of dysphagia and other complications.

Conclusion

Use of CO₂ insufflation for ESD was safe and effective with regard to abdominal discomfort, procedure time, and the residual gas volume. However, there appeared no significant differences with respect to other parameters namely, PtcCO₂, PaCO₂, SpO₂%, abdominal circumference, hospital stay, sedation dosage, complications, WBC, CRP, and dysphagia.

Carbon Dioxide versus Air Insufflation in Gastric Endoscopic Submucosal Dissection: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background/Aims

Endoscopic submucosal dissection (ESD) with air insufflation is commonly used for the staging and treatment of early gastric carcinoma. However, carbon dioxide (CO₂) use has been shown to cause less post-procedural pain and fewer adverse events. The objective of this study was to compare the post-procedural pain and adverse events associated with CO₂ and air insufflation in ESD.

Methods

A systematic search was conducted for randomized control trials (RCTs) comparing the two approaches in ESD. The Mantel-Haenszel method was used to analyze the data. The mean difference (MD) and odds ratio (OR) were used for continuous and categorical variables, respectively.

Results

Four RCTs with a total of 391 patients who underwent ESD were included in our meta-analysis. The difference in maximal post-procedural pain between the two groups was statistically significant (MD, -7.41; 95% confidence interval [CI], -13.6 – -1.21; p=0.020). However, no significant differences were found in the length of procedure, end-tidal CO₂, rate of perforation, and postprocedural hemorrhage between the two groups. The incidence of overall adverse events was significantly lower in the CO₂ group (OR, 0.51; CI, 0.32–0.84; p=0.007).

Conclusions:

CO₂ insufflation in gastric ESD is associated with less post-operative pain and discomfort, and a lower risk of overall adverse events compared with air insufflation.

Carbon Dioxide Versus Air Insufflation for Elective Colonoscopy: A Meta-Analysis and Systematic Review of Randomized Controlled Trials

AIMS AND OBJECTIVE

The aim of this study was to conduct a meta-analysis and systematic review of randomized controlled trials (RCTs) comparing 2 methods of colonic insufflation for elective colonoscopy, that is, carbon dioxide (CO2) or air, and to evaluate their efficiency, safety, and side effects.

MATERIALS AND METHODS

Prospective RCTs comparing CO2 versus air insufflation for colonic distension during colonoscopy were selected by searching PubMed, Medline, Embase, Science Citation Index, Current Contents, and the Cochrane Central Register of Controlled Trials published between January 1980 and October 2014. The outcome variables analyzed included procedural and immediate postprocedural pain (during, end, or within 15 min after procedure), early postprocedural pain (between 30 and 120 min), intermediate postprocedural pain (360 min) and late postprocedural pain (720 to 1140 min), cecal/ileal intubation rate, cecal/ileal intubation time, and total colonoscopy examination time. These outcomes were unanimously decided to be important as they influence the practical approach toward patient management within and outside of hospital. Random effects model was used to calculate the effect size of both binary and continuous data. Heterogeneity among the outcome variables of these trials was determined by the Cochran Q statistic and I2 index. The meta-analysis was prepared in accordance with PRISMA guidelines.

RESULTS

Twenty-four RCTs totaling 3996 patients (CO2=2017, Air=1979) were analyzed. Statistically significant differences for the pooled effect size were observed for procedural and immediate postprocedural pain [weighted mean difference (WMD)=0.49; 95% confidence interval (CI), 0.32, 0.73; P=0.0005], early postprocedural pain between 30 and 120 minutes (WMD=0.25; 95% CI, 0.12, 0.49; P<0.0001), intermediate postprocedural pain, that is, 360 minutes after completion (WMD=0.35; 95% CI, 0.23, 0.52; P<0.0001), and late postprocedural pain between 720 and 1440 minutes (WMD=0.53; 95% CI, 0.34, 0.84; P=0.0061). Comparable effects were noted for cecal/ileal intubation rate (WMD=0.86; 95% CI, 0.61, 1.22; P=0.3975), cecal/ileal intubation time (WMD=-0.64; 95% CI, -1.38, 0.09; P=0.0860), and total examination time (WMD=-0.20; 95% CI, -0.96, 0.57; P=0.6133).

CONCLUSIONS

On the basis of our meta-analysis and systematic review, we conclude that CO2 insufflation significantly reduces abdominal pain during and following the procedure lasting up to 24 hours. There is no difference in the cecal/ileal intubation rate and time and total examination time between the 2 methods. CO2 retention with CO2 insufflation during and after the colonoscopy shows inconsequential variation compared with air insufflation and has no adverse effect on patients. CO2 instead of air should be routinely utilized for colonoscopy.

Single-Balloon Enteroscopy

Single-balloon enteroscopy is among 3 device-assisted enteroscopy systems on the market. Compared with double-balloon enteroscopy, no significant difference in diagnostic yield was found. Additionally, no significant difference was found in oral and anal insertion depth, adverse events, or procedure times. Some studies observed lower complete enteroscopy rates, which have evidently no diagnostic impact. With a learning curve of around 30 procedures, the single-balloon endoscope is a safe endoscopic tool, which seems equally suitable for diagnostic and therapeutic interventions. Carbon dioxide should be used for single-balloon endoscopy procedures, especially in patients with a history of surgical abdominal interventions.

Complications of diagnostic colonoscopy, upper endoscopy, and enteroscopy

Endoscopy is an inherent and an invaluable tool in every gastroenterologist's armamentarium. The prerequisite for quality and safety remains foremost. Adverse events should be minimized and proactive steps should taken before, during and after the endoscopic procedure. Upper endoscopy and colonoscopy are part of basic endoscopy and their major complications will be reviewed here, together with those of enteroscopy. The most common of all endoscopy related complications are cardiopulmonary and thus they will be addressed in detail first. Colonoscopy's major complications are bleeding and perforation. Their epidemiology, mechanisms/risk factors, diagnosis, treatment and prevention will be addressed. The incidence of both of these complications increases significantly with polypectomy. Thus clinical judgment and experience in both polypectomy techniques and the ways to treat these complications, especially with the advanced endoscopic options advanced in the last decade, are of paramount importance. Post-polypectomy syndrome, infection and gas explosion are less frequent and will be reviewed briefly. Bleeding and perforation are upper endoscopy's major complications as well. Advances in endoscopic techniques in recent years offer endoscopic treatment instead of directly resorting to surgery, as was used to be the case and still is if the first fails. Enteroscopy is generally a more advanced procedure and overall complication rate is often quoted as 1%, most of them have been attributed to the passage of the overtube. Perforation and bleeding are the major complications, and a unique upper enteroscopy-associated complication is pancreatitis.

A randomized controlled trial comparing water exchange and air insufflation during colonoscopy without sedation

OBJECTIVES

Previous studies have shown that water exchange is superior to air insufflation in attenuating insertion pain during colonoscopy. We conducted a randomized controlled trial with head-to-head comparison of these methods to assess their effectiveness in colonoscopy without sedation.

METHODS

A total of 447 outpatients were randomized to either water exchange (WE) or the standard air (CO2) insufflation (AI). The primary outcome was the improvement of patient intraprocedural pain (pain score), evaluated using a questionnaire (scores 1 to 5).

RESULTS

After exclusion of 44 patients from further analysis, 403 patients were analyzed. There was no difference in clinical background between the WE and AI groups. Patients in the WE group reported less intraprocedural pain than those in the AI group (2.17 ± 1.06 vs. 2.42 ± 1.03; unpaired t test, p = 0.021). We divided the cases into two groups, more or less painful colonoscopy, based on age, body mass index, use of anti-peristaltic drugs or not, and physician's experience. In less painful colonoscopy, the WE method could reduce pain effectively but its effect was limited in the more painful group.

CONCLUSION

WE is superior to AI for attenuating insertion pain during colonoscopy without sedation, but its efficacy is limited in more painful endoscopy.

The effectiveness of FOBT vs. FIT: A meta-analysis on colorectal cancer screening test

BACKGROUND

After lung and prostate cancers, colorectal cancer (CRC) is the third most common cancer in men and the second most common cancer in women after breast cancer worldwide. Every year, more than one million people are diagnosed with colorectal cancer worldwide and half of these patients die from this disease, making it the fourth leading cause of death in the world. This systematic review aimed to assess the effectiveness of the two colorectal diagnostic tests of FOBT (fecal occult blood test) and FIT (fecal immunochemical test)) in terms of technical performance.

METHODS

To retrieve the relevant evidence, appropriate medical databases such as Cochrane library, NHSEED, Scopus and Google scholar were searched from February 2013 to July 2014, using free-texts and Mesh. In this study, inclusion/exclusion criteria of the papers, randomized controlled trials, economic evaluations, systematic reviews, meta-analyses and meta-syntheses of the effectiveness of FIT versus FOBT tests in moderate-risk populations (age: 50 to 70 years), which had reported the least of such outcomes as sensitivity, specificity and clinical outcomes were reviewed. The analyses of the effectiveness outcomes were performed in the form of meta-analysis.

RESULTS

Five papers were eligible to be included in the final phase of the study for synthesis. FIT showed a better performance in participation and positivity rate. Moreover, in terms of false positive and negative rate, FIT showed fewer rates compared to FOBT (RR:-4.06; 95% CI (-7.89-0.24), and NN-scope (Number need to scope) (2.2% vs. 1.6%), and NN-screen (Number need to screen) (84% vs. 31-49% in different cut off levels) showed significant differences in FOBT vs. FIT, respectively.

CONCLUSION

In the five included studies (3, 11-14), the acceptability of FIT was more than FOBT. However, in our meta-analysis, no difference was found between the two tests. FIT was significant in positivity rate and had a better performance in participation rate, and a fewer false negative numbers compared to FOBT.

Randomized, double-blind trial of CO2 versus air insufflation in children undergoing colonoscopy

BACKGROUND AND AIMS

Studies in adults have shown that postprocedural abdominal pain is reduced with the use of carbon dioxide (CO(2)) instead of air for insufflation during colonoscopy. The aim of our study was to compare postprocedural abdominal pain and girth in children undergoing colonoscopy using CO(2) or air for insufflation.

METHODS

This was a prospective, randomized, double-blind study that included 76 consecutive pediatric patients undergoing colonoscopy for various indications. Patients were randomly assigned to either CO(2) or air insufflation. At 2, 4, and 24 hours after the examination, the patients' pain was assessed by using the 11-point numerical rating scale. The waist circumference was measured 10 minutes and 2 and 4 hours after colonoscopy.

RESULTS

A significantly higher proportion of patients had no pain after colonoscopy in the CO(2) group compared with the air group (82 vs 37% at 2 hours and 95% vs. 63% at 4 hours, P < .001). Mean abdominal pain scores 2 and 4 hours after the procedure were statistically significantly lower in the CO(2) group compared with the control air group (0.5 vs 2.6 at 2 hours and 0.1 vs 1.2 at 4 hours, P < .001). There was no difference in waist circumference between the 2 groups at all time intervals.

CONCLUSION

The results of this randomized trial show clear benefits of CO(2) insufflation for colonoscopy in reducing postprocedural discomfort. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT02407639.).

Carbon dioxide insufflation during colonoscopy can significantly decrease post-interventional abdominal discomfort in deeply sedated patients: A prospective, randomized, double-blinded, controlled trial

BACKGROUND AND AIM

CO2 has been reported to be absorbed from the bowel more rapidly than air, resulting in a discomfort reduction after colonoscopy. Its role in deeply sedated patients is limited. This study was designed to investigate the efficacy and safety of CO2 insufflation during colonoscopy in patients deeply sedated with propofol.

METHODS

A total of 125 continuous patients were randomly assigned to receive either CO2 (n = 63) or air (n = 62) insufflation during propofol-sedated colonoscopy. Postcolonoscopy abdominal pain, distention, and satisfaction were assessed at 1, 3, and 24 h after the procedure, and the proportions of pain-free and distention-free patients were compared. Residual bowel gas in the colon and small bowel was evaluated at 1 h after colonoscopy. End-tidal CO2 and O2 saturation was measured for safety analysis.

RESULTS

There was a significant difference between the two groups regarding the postcolonoscopy abdominal pain, distention, and subjective satisfaction at 1 h (P < 0.001) and 3 h (P < 0.01) after the procedure. Patients' pain and distention at 1 and 3 h after the procedure were significantly lower in the CO2 group (P < 0.01). Residual bowel gas in the colon and small bowel was significantly less in the CO2 group (P < 0.001). There was no significant difference in end-tidal CO2 levels between two groups before, during, and after the procedure.

CONCLUSIONS

Compared with air, CO2 insufflation during colonoscopy reduced postcolonoscopy abdominal discomfort and improved patients' satisfaction. It was safe to use CO2 insufflation in deeply sedated colonoscopy.

Carbon dioxide insufflation or warm-water infusion for unsedated colonoscopy: A randomized controlled trial in patients with chronic constipation in China

AIMS

The effect of carbon dioxide (CO2) insufflation and warm-water infusion during colonoscopy on patients with chronic constipation remains unknown. We evaluated CO 2 insufflation and warm-water irrigation versus air insufflation in unsedated patients with chronic constipation in China.

PATIENTS AND METHODS

This randomized, single-center, controlled trial enrolled 287 consecutive patients, from January 2014 to January 2015, who underwent colonoscopy for chronic constipation. Patients were randomized to CO2 insufflation, warm-water irrigation and air insufflation colonoscopy insertion phase groups. Pain scores were assessed by the visual analog scale (VAS). The primary outcome was real-time maximum insertion pain, recorded by an unblinded nurse assistant. At discharge, the recalled maximum insertion pain was recorded. Meanwhile, patients were requested to select the VAS at 0, 10, 30, and 60 min after the procedure. In addition, cecal intubation and withdrawal time, total procedure time, and adjunct measures were recorded.

RESULTS

A total of 287 patients were randomized. The correlation between real-time and recalled maximum insertion pain ((Pearson coefficient r = 0.929; P < 0.0001) confirmed internal validation of the primary outcome. The mean real-time maximum pain scores during insertion 2.9 ± 2.1 for CO2, 2.7 ± 1.9 for water achieved a significantly lower pain score compared with air (5.7 ± 2.5) group (air vs CO2 P < 0.001; air vs water P < 0.001). However, no significant pain score differences were found between the patients in the CO2 and water groups (CO2 vs water, P = 0.0535). P values in painless colonoscopy and only discomfort colonoscopy (pain 1-2) were, respectively, 6 (6.4%) and 8 (8.5%) for air; 17 (17.7%) and 29 (30.2%) for CO2; 16 (16.5%) and 31 (31.9%) for water. At 0, 10, 30, and 60 min postprocedure, pain scores showed in the CO2 and water groups had significantly reduced than in air group. Insertion time was significantly different between air (10.6 ± 2.5) and CO2 ( 7.2 ± 1.4) (air vs CO2 P < 0.001), air and water (6.9 ± 1.3) (air vs water P < 0.001). However, CO2 and was not significantly different in cecum-intubated time (CO2 vs water, P = 0.404). CO2 and water group in extubation time were significantly different, respectively, CO2 (7.9 ± 1.1) and water (8.0 ± 1.1) (CO2 vs water, P = 0.707). CO2 or water group required less implementation of adjunct measures and more willingness to repeat the procedure.

CONCLUSIONS

Compared with air, the CO2 or water-aided method reduced real-time maximum pain and cecum-intubated time for chronic constipated patients in unsedated colonoscopy. The CO2 insufflation or warm-water irrigation may be a simple and inexpensive way to reduce discomfort in unsedated patients with constipation. This study demonstrated an advantage of using CO2 insufflation and warm-water irrigation during colonoscopy in unsedated constipated patients in China.

Evaluation of abdominal circumference and salivary amylase activities after unsedated colonoscopy using carbon dioxide and air insufflations

OBJECTIVE

To assess and compare abdominal distention and stress in unsedated colonoscopy using carbon dioxide (CO2 ) and air insufflations.

METHODS

Two hundred and five patients underwent colonoscopic examinations without sedation using either CO2 or air insufflation. Abdominal circumference and salivary amylase (sAMY) activities before and 0 and 15 min after colonoscopy were measured by a nurse who was blinded to the grouping of the patients.

RESULTS

In all, 102 and 103 patients were randomly recruited in the CO2 and air insufflation groups, respectively. sAMY activities before and 0 and 15 min after colonoscopy were not significantly different between the two groups. Abdominal circumference measured immediately and 15 min after colonoscopy was significantly smaller in CO2 insufflation group than in the air insufflation group (81.2 cm vs 84.0 cm, and 79.7 cm vs 83.6 cm, respectively; P <0.05). The increasing ratio of abdominal circumference immediately after colonoscopy was not significantly different between the two groups; however, the ratio at 15 min after colonoscopy using CO2 insufflation was significantly lower than that in the air insufflation group (1.007 vs 1.028, P <0.001).

CONCLUSION

sAMY activities after unsedated colonoscopy using CO2 insufflation were not improved; however, CO2 insufflation decreases abdominal circumference after colonoscopy compared with air insufflation.

Efficacy of carbon dioxide insufflation during gastric endoscopic submucosal dissection: a randomized, double-blind, controlled, prospective study

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is commonly performed under air insufflation and is often accompanied by abdominal discomfort. CO2 is absorbed more rapidly by the body than is air; however, the use of CO2 insufflation in ESD remains controversial. This randomized, double-blind, controlled, prospective study was designed to assess the efficacy of CO2 versus air insufflation in gastric ESD.

METHODS

Between May 2012 and August 2014, a total of 110 patients with gastric tumors were randomly assigned to the CO2 insufflation (CO2 group, n = 54) or air insufflation group (air group, n = 56). Abdominal pain after ESD was chronologically recorded via visual analog scale (VAS) scores. Secondary outcome measurements were adverse events, abdominal circumference, amount of sedatives prescribed, and use of analgesics.

RESULTS

Neither the baseline patient characteristics nor the mean procedural time differed between the groups. The VAS score for abdominal pain was 35.2 in the CO2 insufflation group versus 48.5 in the air insufflation group 1 hour after ESD (P = .026), 27.8 versus 42.5 three hours after ESD (P = .007), 18.4 versus 34.8 six hours after ESD (P = .001), and 9.2 versus 21.9 one day after ESD (P < .001). Changes in abdominal circumference, the amounts of sedative drugs taken, and the adverse events did not differ between the groups. However, the air insufflation group required more analgesics than did the CO2 insufflation group (CO2 group, 22.0% [11/50]; air group, 42.3% [22/52]; P = .028).

CONCLUSIONS

CO2 insufflation during gastric ESD significantly reduced abdominal pain and analgesic usage compared with air insufflation. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01579071.)

Colorectal endoscopic submucosal dissection: Recent technical advances for safe and successful procedures

Endoscopic submucosal dissection (ESD) is very useful in en bloc resection of large superficial colorectal tumors but is a technically difficult procedure because the colonic wall is thin and endoscopic maneuverability is poor because of colonic flexure and extensibility. A high risk of perforation has been reported in colorectal ESD. To prevent complications such as perforation and unexpected bleeding, it is crucial to ensure good visualization of the submucosal layer by creating a mucosal flap, which is an exfoliated mucosa for inserting the tip of the endoscope under it. The creation of a mucosal flap is often technically difficult; however, various types of equipment, appropriate strategy, and novel procedures including our clip-flap method, appear to facilitate mucosal flap creation, improving the safety and success rate of ESD. Favorable treatment outcomes with colorectal ESD have already been reported in many advanced institutions, and appropriate understanding of techniques and development of training systems are required for world-wide standardization of colorectal ESD. Here, we describe recent technical advances for safe and successful colorectal ESD.

Objective volumetric comparison of room air versus carbon dioxide for colonic distention at screening CT colonography

PURPOSE

To objectively compare colonic distention at CT colonography (CTC) achieved with manual room air vs. automated low-pressure carbon dioxide (CO2) using a novel automated volumetric quality assessment tool.

METHODS

Volumetric analysis was retrospectively performed on CTC studies in 300 asymptomatic adults using an automated quality assessment tool (V3D Colon [beta version], Viatronix). Colonic distention was achieved with room air self-administered to tolerance via hand-held pump (mean number of pumps, 39 ± 32) in 150 individuals (mean age, 59 years; 98 men, 51 women) and via continuous low-pressure automated infusion of CO2 in 150 individuals (mean age, 57 years; 89 men, 61 women). CTC studies in supine and prone position were assessed to determine total colonic volume (luminal gas and fluid). The colonic length along the automated centerline was also recorded to enable calculation of length-adjusted colonic volumes.

RESULTS

The mean total colonic volume (±SD) for individuals receiving room air and CO2 distention was 1809 ± 514 and 2223 ± 686 mL, respectively (p < 0.01). The prone position was better distended in 78.7% (118/150) of cases using room air; whereas, the supine was better in 66.0% (99/150) of CO2 cases (p < 0.01). Using a volume threshold of 2000 mL, 49 (32.7%) of room air cases and 92 (61.3%) of CO2 cases were above this cut-off. The mean length-adjusted colonic volume (mL/cm) for the room air and CO2 techniques was 9.9 ± 2.4 and 11.6 ± 2.6 mL/cm (p < 0.01).

CONCLUSIONS

Using automated volumetry allowed quantitative analyses of colonic volumes and objectively confirmed that continuous low-pressure CO2 provides greater overall colonic distention than the manual room air technique at CTC. The supine position demonstrated better distention with CO2, whereas the prone position was better distended with the room air technique.

Gastrointestinal cancer screening: screening may release new research funding to improve health service also in routine clinics

We are far from having seen the ideal method of screening for colorectal cancer (CRC) and the downsides of screening have not been fully addressed. Funding of adequately sized screening trials with a 10-15-year perspective for endpoints CRC mortality and incidence is difficult to get. Also, with such time horizons, there will always be an ongoing study to be awaited before feeling obliged to invest in the next. New, promising screening methods may, however, emerge far more often than every 10th year, and the knowledge gap may easily widen unless research is made a key responsibility for any ongoing cancer screening program. Previous lost battles on screening research may be won if accepting that scientific evidence may be obtained within the framework of screening programs - provided that they are designed as platforms for Comparative Effectiveness Research (CER). Accepting that CER-based screening programs should be preferred to non-CER programs and seriously compete for their funding sources, then CER screening programs may not be considered so much as contenders for ordinary clinical research funds. Also, CER within a screening framework may benefit patients in routine clinics as shown by screening research in Nordic countries. The Nordic countries have been early contributors to research on CRC screening, but slow in implementing screening programs.

Carbon dioxide insufflation vs conventional air insufflation for colonoscopy: a systematic review and meta-analysis of published randomized controlled trials

AIM

Conventional air insufflation (AI) may cause prolonged abdominal bloating, excessive abdominal pain and discomfort during colonoscopy. Carbon dioxide may be an acceptable alternative to avoid these complications. The object of this study was to evaluate systematically the effectiveness of carbon dioxide insufflation (CI) for colonoscopy compared with AI.

METHOD

Randomized controlled trials (RCTs) comparing the effectiveness of CI with that of AI during colonoscopy were retrieved from medical electronic databases and combined analysis was performed using the RevMan statistical package. The combined outcome of dichotomous and continuous variables was expressed as an odds ratio (OR) and standardized mean difference (SMD).

RESULTS

Twenty-one RCTs comprising 3607 patients were included in the study. There was statistically significant heterogeneity among included studies. CI showed a significant trend towards reduced procedural pain [SMD -1.34; 95% confidence interval (95% CI) -2.23 to -0.45; z = 2.96; P < 0.003] and also postprocedural pain at 1 h (SMD -1.11; 95% CI -1.83 to -0.38; z = 2.97; P < 0.003), 6 and 24 h (OR 0.44; 95% CI 0.23-0.85; z = 2.44; P < 0.01). CI was associated with faster caecal intubation (SMD -0.20; 95% CI -0.37 to -0.02; z = 2.23; P < 0.03) but the caecal intubation rate was similar (P = 0.59) in both colonic insufflation techniques .

CONCLUSION

CI seems to have clinical advantages over AI for colonoscopy with regard to pain during and after the procedure.

Peroral endoscopic myotomy for esophageal achalasia

Peroral endoscopic myotomy (POEM) is one of the alternative treatment for achalasia. Due to concept of natural orifice transluminal endoscopic surgery (NOTES), it becomes popular and widely accepted. With the endoluminal technique, submucosal tunnel was created followed by endoscopic myotomy. POEM is not only indicated in classical achalasia but also other abnormal esophageal motility disorders. Moreover, failures of endoscopic treatment or surgical attempted cases are not contraindicated for POEM. The second attempted POEM is also safe and technically feasible. Even though the legend of success of POEM is fruitful, the possible complications are very frightened. Good training and delicate practice will reduce rate of complications. This review provides a summary of current state-of-the-art of POEM, including indication equipments, technique and complications. This perfect procedure may become the treatment of choice of achalasia and some esophageal motility disorders in the near future.

Safety of carbon dioxide insufflation during gastric endoscopic submucosal dissection in patients with pulmonary dysfunction under conscious sedation

BACKGROUND

Carbon dioxide (CO2) insufflation is effective for gastric endoscopic submucosal dissection (ESD). However, its safety is unknown in patients with pulmonary dysfunction. This study aimed to investigate the safety of CO2 insufflation during gastric ESD in patients with pulmonary dysfunction under conscious sedation.

METHODS

We analyzed 322 consecutive patients undergoing ESD using CO2 insufflation (1.4 L/min) for gastric lesions. Pulmonary dysfunction was defined as a forced expiratory volume in 1.0 s/forced vital capacity (FEV1.0%) <70% or vital capacity <80%. Transcutaneous partial pressure of CO2 (PtcCO2) was recorded before, during, and after ESD.

RESULTS

In total, 127 patients (39%) had pulmonary dysfunction. There were no significant differences in baseline PtcCO2 before ESD, peak PtcCO2 during ESD, and median PtcCO2 after ESD between the pulmonary dysfunction group and normal group. There was a significant correlation between PtcCO2 elevation from baseline and ESD procedure time (r = 0.22, P < 0.05) only in the pulmonary dysfunction group. In patients with FEV1.0% <60%, the correlation was much stronger (r = 0.39, P < 0.05). Neither the complication incidences nor the hospital stay differed between the two groups. CO2 narcosis or gas embolism was not reported in either group.

CONCLUSIONS

CO2 insufflation during gastric ESD in patients with pulmonary dysfunction under conscious sedation is safe with regard to complication risk and hospital stay. However, in patients with severe obstructive lung disease, especially in those with FEV1.0% <60%, longer procedure time may induce CO2 retention, thus requiring CO2 monitoring.