Carbon dioxide insufflation during withdrawal of the colonoscope improved postprocedure discomfort: a prospective, randomized, controlled trial

A meta-analysis of carbon dioxide versus room air insufflation on patient comfort and key performance indicators at colonoscopy

BACKGROUND

Carbon dioxide (CO₂) has been used as an alternative to air insufflation at endoscopy with good results; however, uptake of the technique has been poor, possibly due to perceived lack of outcome equivalency. This meta-analysis evaluates the effectiveness of CO₂ versus air in reducing pain post-colonoscopy and furthermore examines other key performance indicators (KPIs) such as sedative use, procedure times and polyp detection rates.

METHODS

This meta-analysis was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Pubmed, Pubmed Central, Embase and Cochrane Library were searched for randomized studies from 2004 to 2019, reporting outcomes for patients undergoing colonoscopy with air or CO₂ insufflation, who reported pain on a numerical or visual analogue scale (VAS). Results were reported as mean differences (MD) or pooled odds ratios (OR) with 95% confidence intervals (95% CI).

RESULTS

Of 3586 citations, 23 studies comprising 3217 patients were analysed. Patients undergoing colonoscopy with air insufflation had 30% higher intraprocedural pain scores than those receiving CO₂ (VAS 3.4 versus 2.6, MD -0.7, 95% CI - 1.4-0.0, p = 0.05), with a sustained beneficial effect amongst those in the CO₂ group at 30 min, 1-2-h and 6-h post procedure (MD - 0.8, - 0.6 and - 0.2, respectively, p < 0.001 for all), as well as less distension, bloating and flatulence (p < 0.01 for all). There were no differences between the two groups in KPIs such as the sedation required, procedure time, caecal intubation or polyp detection rates.

CONCLUSIONS

CO₂ insufflation improves patient comfort without compromising colonoscopic performance.

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.

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.

Is the type of insufflation a key issue in gastro-intestinal endoscopy?

Endoscopic procedures continue to play an emerging role in diagnosing and treating upper and lower gastrointestinal (GI) disorders. In particular, the introduction of colonoscopy in bowel cancer screening has underlined its promising role in decreasing the incidence of colorectal cancer and reducing tumour related mortality. To achieve these goals patients need to contemplate endoscopic examinations as painless and fearless procedures. The use of carbon dioxide (CO₂) as an alternative insufflation gas in comparison to air has been considered as an essential key to improving patients' acceptance in undergoing endoscopic procedures. CO₂ is absorbed quickly through the bowel mucosa causing less luminal distension and potentially less abdominal pain. However, its exact role has not been defined completely. In particular, the beneficial use of CO₂ in upper GI endoscopy and in sedated patients is still conflicting. In the present review, we aimed to assess the current evidence for using CO₂ in endoscopy and to evaluate its potential role in the future.

Carbon dioxide insufflation or warm-water infusion versus standard air insufflation for unsedated colonoscopy: a randomized controlled trial

BACKGROUND

The increasing demand for colonoscopy has renewed the interest for unsedated procedures. Alternative techniques, such as carbon dioxide insufflation and warm-water infusion, have been advocated to improve patient tolerance for colonoscopy in comparison with air insufflation.

OBJECTIVE

The aim of this study was to evaluate the benefits of carbon dioxide insufflation and warm-water irrigation over air insufflation in unsedated patients.

DESIGN

This study was a randomized, controlled trial.

SETTING

This study was conducted at a nonacademic single center.

PATIENTS

Consecutive outpatients agreeing to start colonoscopy without premedication were included.

INTERVENTIONS

Patients were assigned to either carbon dioxide insufflation, warm-water irrigation, or air insufflation colonoscopy insertion phase. Sedation/analgesia were administered on patient request if significant pain or discomfort occurred.

MAIN OUTCOME MEASURES

The primary outcome measured was the percentage of patients requiring sedation/analgesia. Pain and tolerance scores were assessed at discharge by using a 100-mm visual analog scale.

RESULTS

Three hundred forty-one subjects (115 in the carbon dioxide, 113 in the warm-water, and 113 in the air group) were enrolled. Intention-to-treat analysis showed that the proportion of patients requesting sedation/analgesia during colonoscopy was 15.5% in the carbon dioxide group, 13.2% in the warm-water group, and 25.6% in the air group (p = 0.04 carbon dioxide vs air; p = 0.03 warm water vs air). Median (interquartile range) scores for pain were 30 (10-50), 28 (15-50), and 46 (22-62) in the carbon dioxide, warm-water, and air groups (carbon dioxide vs air, p < 0.01; warm water vs air, p < 0.01); corresponding figures for tolerance were 20 (5-30), 19 (5-36), and 28 (10-50) (carbon dioxide vs air, p < 0.01; warm water vs air, p < 0.01).

LIMITATIONS

This investigation was limited because it was a single-center study and the endoscopists were not blinded to randomization.

CONCLUSIONS

Carbon dioxide insufflation was associated with a decrease in the proportion of patients requesting on-demand sedation, improved patient tolerance, and decreased colonoscopy-related pain in comparison with air insufflation. The findings regarding warm-water irrigation confirmed the previously reported advantages, so that warm-water irrigation and carbon dioxide insufflation could represent competitive strategies for colonoscopy in unsedated patients.

Bringing top-end endoscopy to regional australia: hurdles and benefits

This paper focuses on recent experience in setting up an endoscopy unit in a large regional hospital. The mix of endoscopy in three smaller hospitals, draining into the large hospital endoscopy unit, has enabled the authors to comment on practical and achievable steps towards creating best practice endoscopy in the regional setting. The challenges of using what is available from an infrastructural equipment and personnel setting are discussed. In a fast moving field such as endoscopy, new techniques have an important role to play, and some are indeed cost effective and have been shown to improve patient care. Some of the new techniques and technologies are easily applicable to smaller endoscopy units and can be easily integrated into the practice of working endoscopists. Cost effectiveness and patient care should always be the final arbiter of what is essential, as opposed to what is nice to have. Close cooperation between referral and peripheral centers should also guide these decisions.