No Added Benefit of Capnography in Colonoscopy
"We know moderate sedation for colonoscopy is extremely safe; it's been used on millions of patients," said Paresh Mehta, MD, a former fellow at the Cleveland Clinic, and currently with the Gastroenterology Consultants of San Antonio.
"Does adding a device that costs more money, that requires extra training, that we are not sure even works in patients who may not need it worth it?," he asked.
"I believe this study provides initial evidence that some patient populations, especially healthy adults who are American Society of Anesthesiologists [ASA] physical classification I or II, can safely undergo these procedures without capnographic monitoring, at least when looking at hypoxemia as an outcome," he told Medscape Medical News.
The finding, presented here at the American College of Gastroenterology 2014 Annual Scientific Meeting, counters the recently updated ASA practice guidelines that require capnography when moderate sedation is used during colonoscopy or other procedures.
Dr Mehta and colleagues studied 234 adults scheduled for routine outpatient colonoscopy. Patients were given midazolam for sedation and either fentanyl or meperidine for pain control.
The adults were randomized to either an open or blinded capnography alarm group. Both groups were well matched, and there were no significant differences in body mass index or in patient history of heart or pulmonary disease. In addition to capnographic monitoring, standard cardiopulmonary monitoring devices were used in both groups.
The primary end point of the study was the incidence of hypoxemia, defined as a drop in oxygen saturation to below 90% for at least 10 seconds over a 1-minute period.
Secondary end points included the incidence of severe hypoxia, defined as a drop in oxygen saturation to below 85% at any time during the procedure, the incidence of apnea, disordered respiration, hypotension, bradycardia, and early procedure termination for any cause.