Autonomic nervous responses in colorectal polypectomy: Randomized controlled trial comparing air and carbon dioxide insufflation

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.

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).

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.).