Giles W. Stevenson

Minimizing postcolonoscopy abdominal pain by using CO2 insufflation: A prospective, randomized, double blind, controlled trial evaluating a new commercially available CO2 delivery system

BACKGROUND Abdominal pain after colonoscopy is a common, distressing symptom resulting from bowel distension by insufflated gas. CO(2), unlike air, is rapidly cleared from the colon by passive absorption. A commercially available CO(2) delivery system has only recently become available. The effects of CO(2) and air insufflation on residual bowel gas and postprocedure pain were compared. METHODS One hundred patients were randomized to undergo colonoscopy with insufflation of air (n = 51) or CO(2) (n = 49) by means of a regulator; 97 patients completed the study. Patients with active GI bleeding, inflammatory bowel disease, or previous colectomy were excluded. Pain scores (ordinal scale: 0 = none, to 5 = extreme) were recorded immediately after colonoscopy and at 1, 6, and 24 hours. Residual colonic gas was evaluated on abdominal radiographs at 1 hour. RESULTS Residual colonic gas and postprocedural pain at 1 and 6 hours were significantly less in the CO(2) group. 71% of patients insufflated with room air had colonic distension in excess of 6 cm versus 4% for those in the CO(2) group. 94% of patients insufflated with CO(2) had minimal colonic gas versus 2% in whom air was used (p < 0.0001). Of patients insufflated with air, 45% and 31% had pain at, respectively, 1 hour and 6 hours, versus 7% and 9%, respectively, for those insufflated with CO(2) (respectively, p < 0.0001 and p < O.02). No complications resulted from use of the CO(2) delivery system. CONCLUSIONS Insufflation of CO(2) rather than air significantly reduces abdominal pain and bowel distension after colonoscopy. CO(2) may be insufflated safely and effectively with the new CO(2) delivery system.

Pain following colonoscopy: elimination with carbon dioxide

Fifty-six patients have been examined in a prospective randomized study on the effects of air and carbon dioxide on post-procedural discomfort following colonoscopy. A significant reduction in post-procedural pain was observed at 6 hours (p = < 0.0005) and was still present the next day (p = 0.01). This was associated with a difference in the grading of flatus at 6 and 24 hours (p = < 0.0001 and < 0.05, respectively). An abdominal radiograph 1 hour after the procedure showed minimal gas in the CO2 patients, while the patients who had air showed distention of large and small bowel (p = < 0.0001 and < 0.01, respectively). Seventeen of 29 patients who had air suffered post-procedural pain, compared with 2 of 27 of the CO2 patients. Fifty-seven percent of the patients who were given air had colonic diameters over 6 cm on a 1-hour post-colonoscopy radiograph and 18% over 10-cm diameter. Provision by equipment manufacturers of simple and safe devices for routine delivery of CO2 for lower gastrointestinal endoscopy is long overdue.

Who needs radiology?: A/S/G/E Distinguished Lecture 1980

It is a great honor to give this lecture to our Society, and I am most grateful for the opportunity you have given me to review some of the ways in which radiology and endoscopy may be used in the care of patients. The subject is very large, and I have decided to limit my comments almost completely to barium radiology and endoscopy.

Laxatives prior to small bowel follow-through: are they necessary for a rapid and good-quality examination?

Fifty-six patients undergoing small bowel follow-through examination were randomly allocated to two groups to assess the effect of preparation with laxative on the speed and quality of the examination. We found that laxative had no effect on either speed of the examination or quality of visualization of small bowel. However, the latter was dependent on the degree of supervision and technique of the examining radiologist.

Two- and Three-Dimensional Examination of the Stomach (Virtual Gastroscopy): Technical Note

Endoscopy of the stomach is performed so routinely and with acceptable results that there are few requests for detailed radiologic examination, predominantly after bariatric or hiatus hernia surgery. Nevertheless, computed tomographic (CT) examination with 3-dimensional (3D) virtual gastroscopy may provide additional and complementary information useful in therapeutic decision making, and it also offers an alternative gastric examination for patients in whom conventional endoscopy is not straightforward. Abdominal CT is usually performed without gastric distention. However, double-contrast barium meals and enemas, enteroclysis, CTof the colon, and CT enterography of the small intestine have all shown that distention of the alimentary tract is critical for demonstration of mucosal pathology. Horton and Fishman [1] suggested the use of water for gastric distention. Springer et al [2] obtained the best results with air contrast but found 3D spatial resolution to be limited by computer performance and software constraints at that time. More recently, with the advent of rapid 3D applications, some investigators have evaluated CT 3D gastric imaging, with and without 2-dimensional (2D) imaging, and described promising results for characterizing advanced gastric cancer [3], gastrointestinal stromal tumours (GIST) [4], and moderate results for early gastric cancer [4e6]. In this technical note, we present one approach to 3D CT examination of the stomach.

Procedures in gastrointestinal radiology

This book presents several gastrointestinal radiology techniques. Contrast studies are emphasized as well as endoscopic procedures, thus enabling the radiologist to choose the appropriate technology. Each procedure is discussed with reference to materials, patient preparation. positioning, technical factors, and potential problems. Patient-radiologist interaction before, during, and after the results of the study are emphasized.

Bowel Preparation Suitable for Same-day Computed Tomography Colonography and Colonoscopy

Purpose This study was designed to evaluate whether a bowel preparation used for computed tomography (CT) colonography could also be suitable for same-day colonoscopy regardless of which test was done first. Method Six different endoscopists working at 3 separate hospitals evaluated 75 patients who underwent colonoscopy after receiving a bowel preparation that contained contrast material used to tag fecal and fluid material to facilitate CT colonography. This bowel preparation has been used in more than 1500 CT colonography studies. Evaluation included assessment of whether the colon was clean and dry, and whether the contrast material caused any impairment of visualization or clogging of the endoscopes. Some of the patients had first undergone CT colonography followed by same-day colonoscopy, whereas other patients had colonoscopy as their initial test. Results Although the contrast material was sometimes perceptible, the volumes were very small, and caused no impairment of mucosal visualization and no clogging of the endoscopes. The bowel preparation was well tolerated. Same-day CT colonography and colonoscopy with fecal tagging was technically possible. Conclusion A simple, fairly low cost 1-day bowel preparation with fluid and fecal tagging is suitable for CT colonography and colonoscopy done the same day in either order. However, the preferences of individual endoscopists and difficulties with making oral contrast agents readily available are challenges to widespread adoption of a common bowel preparation regimen.

Bowel preparation regimen for computed tomography colonography.

Purpose This study was designed to determine whether a reduction in oral contrast dose and a change in timing of administration will result in less residual material in the colonic lumen. Method We retrospectively assessed, in a blinded fashion, the amount and nature of residual material in the colon in 40 patients who received computed tomography colonography. Half of the cohort received the standard bowel-preparation regimen, whereas a sex- and age-matched test arm received the modified regimen. A scoring system that consisted of metrics to quantify the nature and extent of residual fluid and solid material was defined. Image analysis was conducted with the investigators blinded to the group assignment of each patient. Three different trained observers independently reviewed and scored the 6 colonic segments in supine and prone positions for each patient in the cohort. In cases in which interobserver discrepancies existed, the observers reanalyzed the images together to come to an agreement on scores. Results The new bowel-preparation regimen resulted in significantly less “sticky coat” (P < .005), a problematic phenomenon in which the colonic mucosa is covered in a thin coating of residual contrast and fecal material. There was no difference in the amount of residual fluid. Fewer masses of stool were noted with the new preparation, but this was not found to be statistically significant. Conclusion A new bowel-preparation regimen that consisted of lower quantities of contrast administered earlier in the day preceding computed tomography colonography resulted in a lower incidence of adherent contrast and fecal matter. The reduction of this “sticky coat” problem not only improved radiologic analysis of the colon but may permit same-day therapy via colonoscopy if indicated on imaging.

2048 x 2048 (2K) digital videofluorography (DVF): a clinical perspective

Digital Video Fluorography (DVF) has been developed over the past fifteen years. Although much emphasis has been placed upon digital subtraction angiography (DSA) the concept has been extended to gfluoroscopic examinations. Indeed, 1024 x 1024 DVF systems are currently being marketed by all major equipment manufacturers. In spite of these developments there are many in the Radiology Community who exhibit reservations which can, on occasion, manifest as outright antagonism to this new technology.

Ultrasound Training for Nonradiologists

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