Capnographic Monitoring in Routine EGD and Colonoscopy With Moderate Sedation: A Prospective, Randomized, Controlled Trial

Am J Gastroenterol. 2016 Mar;111(3):395-404. doi: 10.1038/ajg.2015.437. Epub 2016 Feb 23.


Objectives: Regulatory changes requiring the use of capnographic monitoring for endoscopic procedures using moderate sedation have placed financial challenges on ambulatory and hospital endoscopy centers across the United States due to the increased cost of training endoscopy personnel and purchasing both capnography-monitoring devices and specialized sampling ports. To date, there has been no published data supporting the use of capnographic monitoring in adult patients undergoing routine endoscopic procedures with moderate sedation. The aim of this randomized, parallel group assignment trial was to determine whether intervention based on capnographic monitoring improves detection of hypoxemia in patients undergoing routine esophagogastroduodenoscopy (EGD) or colonoscopy with moderate sedation.

Methods: Healthy patients (ASA Physical Classification (ASAPS) I and II)) scheduled for routine outpatient EGD or colonoscopy under moderate sedation utilizing opioid and benzodiazepine combinations were randomly assigned to a blinded capnography alarm or open capnography alarm group. In both study arms, standard cardiopulmonary monitoring devices were utilized with additional capnographic monitoring. The primary end point was the incidence of hypoxemia defined as a fall in oxygen saturation (SaO2) to <90% for ≥10 s. Secondary outcomes included severe hypoxemia, apnea, disordered respirations, hypotension, bradycardia, and early procedure termination for any cause.

Results: A total of 452 patients were randomized; 218 in the EGD and 234 in the colonoscopy groups; 75 subjects in the EGD group (35.9%) and 114 patients (49.4%) in the colonoscopy group were male, and average body mass index was 27.9 and 29.1 (kg/m(2)), respectively. The blinded and open alarm groups in each study arm were similar in regards to use of opioids and/or benzodiazepines and ASAPS classification. There was no significant difference in rates of hypoxemia between the blinded and open capnography arms for EGD (54.1% vs. 49.5; P=0.5) or colonoscopy (53.8 vs. 52.1%; P=0.79).

Conclusions: Capnographic monitoring in routine EGD or colonoscopy for ASAPS I and II patients does not reduce the incidence of hypoxemia ( number, NCT01994785).

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Analgesics, Opioid* / administration & dosage
  • Analgesics, Opioid* / adverse effects
  • Benzodiazepines* / administration & dosage
  • Benzodiazepines* / adverse effects
  • Capnography / methods*
  • Colonoscopy* / adverse effects
  • Colonoscopy* / methods
  • Conscious Sedation* / adverse effects
  • Conscious Sedation* / methods
  • Endoscopy, Digestive System* / adverse effects
  • Endoscopy, Digestive System* / methods
  • Female
  • Humans
  • Hypnotics and Sedatives / administration & dosage
  • Hypnotics and Sedatives / adverse effects
  • Hypoxia / diagnosis*
  • Hypoxia / etiology
  • Hypoxia / prevention & control
  • Intraoperative Complications / diagnosis*
  • Intraoperative Complications / prevention & control
  • Male
  • Middle Aged
  • Monitoring, Physiologic / methods
  • Treatment Outcome


  • Analgesics, Opioid
  • Hypnotics and Sedatives
  • Benzodiazepines

Associated data