Carbon dioxide versus room air for colonoscopy in deeply sedated pediatric patients: a randomized controlled trial

Background and study aims Use of carbon dioxide (CO2) instead of room air (RA) during colonoscopy in adults revealed significantly less flatulence and abdominal pain in several studies. The objectives of this study were to investigate the effects of CO2 usage on post-interventional pain, abdominal discomfort, abdominal girth, pCO2 levels, and narcotic requirement in deeply sedated pediatric patients. Patients and methods A total of 97 children and adolescents aged 4 years to 17 years undergoing colonoscopy were randomized to RA or CO2 in a prospective, randomized, controlled trial. Age-appropriate pain scales assessed abdominal pain as primary outcome. In addition, abdominal girth, abdominal bloating, transcutaneous pCO2, narcotic requirement to achieve deeply sedation, and post-procedural analgesic demand was analyzed in 73 patients. Results Overall, significantly fewer patients reported bloating in the CO2 group (P = 0.0012). However, we observed only a trend to lower post-interventional pain (P = 0.15) and a lower pain score. There was no significant difference in transcutaneous pCO2 level and no adverse events occurred. Although there was no difference in the dosage of propofol and midazolam, we observed a significant increased necessity for use of synthetic opioids in the RA group to achieve optimal examination conditions (P = 0.023). Conclusions The benefits using CO2 in colonoscopy of deeply sedated children predominate. In particular, CO2 insufflation may allow a less painful post-interventional time and it significantly reduces abdominal bloating. Moreover, with CO2, significantly less additional opioids were used. Thus, CO2 insufflation can be considered as safe in deeply sedated patients as there was no relevant pulmonary CO2 retention observed. (DRKS00013914)