Evaluation of complications during and after conscious sedation for endoscopy using pulse oximetry

Gastrointest Endosc. 1993 Sep-Oct;39(5):620-5. doi: 10.1016/s0016-5107(93)70211-4.


All events prolonging an endoscopic procedure or recovery, or requiring a medication or an intervention, were analyzed from a consecutive sample of 508 patients receiving conscious sedation. Although 102 events were identified (20%), 33 of these (7%) were major. These included four episodes of apnea and four patients with a prompt and sustained fall in oxygenation during the procedure; 19 additional patients had a decrease to less than 89% in oxygen saturation in the 30 minutes after the completion of the procedure. The patients with observed events had significantly more major illnesses, a higher fraction older than 70 years, and a higher fraction of endoscopic retrograde cholangiopancreatography than those without events (p < 0.05) but had a similar dose of sedative medications, mean age, and fraction of colonoscopies.

MeSH terms

  • Age Factors
  • Aged
  • Apnea / diagnosis*
  • Apnea / epidemiology
  • Apnea / etiology
  • Cholangiopancreatography, Endoscopic Retrograde
  • Colonoscopy / adverse effects*
  • Conscious Sedation*
  • Endoscopy, Digestive System / adverse effects*
  • Humans
  • Hypoventilation / diagnosis*
  • Hypoventilation / epidemiology
  • Hypoventilation / etiology
  • Meperidine / therapeutic use
  • Midazolam / therapeutic use
  • Monitoring, Physiologic / methods*
  • Oximetry*
  • Risk Factors


  • Meperidine
  • Midazolam