A comparison of air, CO2 and an air/CO2 mixture as insufflation agents for double contrast barium enema*

Abstract

Using CO2 for DCBE is recommended as it may decrease pain afterwards but recent studies suggest it produces inferior distension. This prospective double blind study was designed to evaluate the use of an air/CO2 mixture. We randomised 105 patients to receive air, CO2 or a 50/50 mixture as the insufflation agent in DCBE. Gases were administered from prefilled bags. Those requiring additional insufflations before over couch films were recorded. Post procedure symptoms were evaluated by questionnaire. Distension and mucosal coating were assessed independently. There was no difference in mucosal coating. Those given CO2 had significantly less immediate and delayed pain compared to air and less delayed pain compared to the 50/50 mixture. Distension with air was graded better than with the other two agents but the difference did not reach statistical significance. However 50 % of patients receiving CO2 and 40 % of those receiving the mixture required additional insufflation before over couch films as distension was considered suboptimal, compared to 17 % of those given air, which was statistically significant. Our results indicate that using CO2 causes less pain than using air or the mixture although top up insufflations are often required to maintain adequate quality distension.

European society of gastrointestinal and abdominal radiology (ESGAR): Consensus statement on CT colonography

“…Use of hyoscine butylbromide has a reasonable evidence base [13][14][15], as does routine supine and prone scanning [16,17] with the lateral decubitus position reserved for those intolerant of lying prone [18]. A small majority of respondents now prefer carbon dioxide for distension [19][20][21]. Although there is some evidence of improved distension with automated insufflation [22], room air remains a simple and practical option.…”

Nonlaxative PET/CT Colonography: Feasibility, Acceptability, and Pilot Performance in Patients at Higher Risk of Colonic Neoplasia

“…We confirmed that the procedure was technically feasible, with generally high-quality distension and bowel preparation; this result was reassuring given the relatively prolonged examination time necessary for PET/ CT colonography in comparison to CT colonography alone. Our choice of carbon dioxide (which is absorbed by the colon) over air was governed by the superior patient tolerance of the former (21). The readers were confident that a lesion greater than 10 cm could be excluded in 98.2% of colonic segments using PET/CT colonography.…”

Current Status of CT Colonography

“…Insufflating the colon with air or carbon dioxide (CO 2 ) allows for polyps to be seen on a CT scan because of the large contrast difference between air and soft tissue. The use of CO 2 to insufflate the colon has been shown to decrease immediate and delayed pain compared to those who receive air (27,28). CO 2 is more easily absorbed through the wall of the colon and therefore causes less cramping and discomfort.…”

“…CO 2 is more easily absorbed through the wall of the colon and therefore causes less cramping and discomfort. However, because CO 2 is absorbed into the body, additional insufflations or an automated pressure-sensing machine may be necessary to maintain the proper colonic distension (27).…”