Carbon Dioxide Insufflation in Colonoscopy Is Safe: A Prospective Trial of 347 Patients

Available evidence suggests that the use of CO 2 insufflation in endoscopy is more comfortable for the patient. The safety of CO 2 use in colonoscopy remains contentious, particularly in sedated patients. The objective of the present prospective trial was to assess the safety of CO 2 colonoscopies. Methods . 109 patients from our previous randomized CO 2 colonoscopy study and an additional 238 subsequent consecutive unselected patients who had a routine colonoscopy performed in a private practice were enrolled from April 2008 through September 2008. All but 2 patients were sedated. All patients were routinely monitored with transcutaneous CO 2 measurement. Volumes of CO 2 administered were correlated with capnographic measurements from transcutaneous monitoring. Results . Of the 347 patients examined, 57% were women; mean (SD) age of participants was of 60.2 years (12.8). Mean propofol dosage was 136 mg (64 mg). Mean CO 2 values were 34.7 mm Hg (5.3) at baseline, 38.9 mm Hg (5.5) upon reaching the ileum, and 36.9 mm Hg (5.0) at examination's end. Mean maximum increase of CO 2 was 4.5 mm Hg (3.6). No correlation was observed between volume of CO 2 administered and increase in level of CO 2 (correlation coefficient: 0.01; P value: 0.84). No complications were observed. Conclusions . The present prospective study, which was based on one of the largest sedated patient sample reported to date in this setting, provides compelling evidence that CO 2 insufflation in colonoscopy is safe and unassociated with relevant increases in transcutaneously measured levels of CO 2 .