Risk Factors for Hypoxemia During Ambulatory Gastrointestinal Endoscopy in ASA I–II Patients

Department of Gastroenterology and Hepatology, Digestive Disease Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, A 30, Cleveland, OH 44195, USA.
Digestive Diseases and Sciences (Impact Factor: 2.61). 11/2008; 54(5):1035-40. DOI: 10.1007/s10620-008-0452-2
Source: PubMed


Most studies identify the American Society of Anesthesiology (ASA) classification as the most significant risk factor for hypoxemia. The risk factors operative within ASA I and II patients are not well defined. Therefore, we analyzed prospectively collected data to identify the risk factors of hypoxemia in such patients.
A combination of a narcotic and benzodiazepine was used for sedation and oxygen was supplemented if hypoxemia (oxygen saturation <or=90%) developed. Univariate and multivariate analyses were performed and correlations estimated for predetermined clinical variables.
40 of 79 patients (51%) developed hypoxemia, which occurred more frequently in the obese (71%; 10/14) than the nonobese (46%; 30/65) group (P=0.08). On multivariate analysis, the odds ratios (OR) and 95% confidence intervals (CI) for developing hypoxemia were age >or= 60 years 4.5 (1.4-14.3) P=0.01, and incremental 25-mg doses of meperidine 2.6 (1.02-6.6) P = 0.04. Body mass index (BMI) significantly correlated with the number of hypoxemic episodes (rho 0.26, 95% CI 0.04-0.48, P=0.02).
In ASA I and II patients, BMI significantly correlated with the number of hypoxemic episodes, whereas age >or= 60 years and meperidine dose were significant risk factors for hypoxemia.

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Available from: Rocio Lopez, Dec 21, 2013
    • "However, at least two studies have shown that obese patients run a higher perioperative risk for adverse airway events. In a prospective observational study involving 79 patients undergoing endoscopy under “conscious sedation,” Qadeer et al.[3] found a 51% overall incidence of hypoxemia (defined as saturation below 90% any time during the procedure, irrespective of the duration of hypoxia). They also found a significant difference in the rates of desaturation between non-obese (46%) and obese group (BMI >30 kg/m2 where it was 71%). "
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    • "Hypoxemia is the most common cardiopulmonary adverse events (CAEs) that may cause morbidity and mortality during endoscopy procedures [8], [12], [13]. The reported risk factors for hypoxemia included high ASA scores, conscious sedation, obesity, old age of patient and function limitation of lung [4]–[9], [11]–[14]. "
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