Arterial Oxygen Desaturation During Endoscopic Ultrasonography Combined with Gastroscopy: a Safety Evaluation in Out-Patients

Introduction

Significant reductions in arterial oxygen saturation (SaO₂) have been observed in patients undergoing gastroscopy, colonoscopy or ERCP, especially in those at risk [1] [2] [3] [4] [5] [6]. Corresponding data for endoscopic ultrasonography (EUS) are not available, but knowledge of potential effects of EUS on SaO₂ is important in view of the rising safety standards and the growing numbers of EUS examinations being carried out, particularly on an outpatient basis [7] [8] [9] [10] [11]. To obtain this information, we continuously monitored the time-related SaO₂ course, pulse rates, and blood pressure in outpatients referred for EUS in order to assess whether EUS in combination with a prior gastroscopy has additional decreasing effects on SaO₂. We were also interested in finding out whether it is possible to identify patients who will be particularly prone to develop relevant SaO₂ desaturation (< 90.0 %) during the procedures, based on their baseline (pre-procedure) arterial oxygen saturation. EUS is usually combined with gastroscopy for better location and visualization of target lesions, due to the superior optical qualities of conventional instruments compared to EUS.

References

• 1 Whorwell PS, Smith CL, Fosk KJ. Arterial blood gas tensions during upper GI endoscopy.  Gut. 1976;  17 797-800
• 2 Bilotta JJ, Floyd JL, Waye JD. Arterial oxygen saturation during ambulatory colonoscopy: predictability, incidence and clinical significance.  Gastrointest Endosc. 1990;  86 (Suppl) S5-8
• 3 Dark DS, Campbell DR, Wesselius U. Arterial oxygen desaturation during gastrointestinal endoscopy.  Am J Gastroenterol. 1990;  85 1317-1321
• 4 Block R, Jankowski J, Johnston D, et al. The administration of supplementary oxygen to prevent hypoxia during upper alimentary tract endoscopy.  Endoscopy. 1993;  25 269-271
• 5 Wong PYN, Lane MR, Hamilton I. Arterial oxygen saturation during endoscopic retrograde cholangiopancreatography [letter].  Endoscopy. 1993;  25 309-310
• 6 Rigg JD, Watt TC, Tweedle DEF, Martin DF. Oxygen saturation during endoscopic retrograde cholangiopancreatography: a comparison of two protocols for oxygen administration.  Gut. 1994;  35 408-411
• 7 Smith MR, Bell JD. Routine oxygen during endoscopy? An editorial review.  Endoscopy. 1993;  25 298-300
• 8 Bell GD, McCloy RF, Charlton JE, et al. Recommendations for standards of sedation and patient monitoring during gastrointestinal endoscopy.  Gut. 1991;  32 823-827
• 9 The Royal College of Surgeons of England Commission on the Provision of Surgical Services. Report of the working party on guidelines for sedation by non-anaesthesiologists.  London; Royal College of Surgeons, 1993
• 10 Allgayer H, Gugler R. Clinical usefulness and cost savings of early endoscopic ultrasound (EUS) in patients with unclear upper GI wall impressions [abstract].  Gastroenterology. 1993;  104 A 383
• 11 Ziegler K, Sanft C, Zeitz M, et al. Evaluation of endosonography in TN staging of oesophageal cancer.  Gut. 1991;  32 16-20
• 12 Hutton P, Clutton-Brock T. The benefits and pitfalls of pulse oximetry.  Br Med J. 1993;  307 457-458
• 13 Rozen P, Fireman R, Gilat T. Arterial oxygen tension changes in elderly patients undergoing upper gastrointestinal endoscopy, 2: influence of narcotic premedication and endoscopic diameter.  Scand J Gastroenterol. 1981;  6 299-303
• 14 Liebermann DA, Wuerker CK, Katon RM. Cardiopulmonary risk of oesophagogastroduodenoscopy: role of endoscopic diameter and systemic sedation.  Gastroenterology. 1985;  88 468-472
• 15 Scott-Coombes DM, Thompson JN. Hypoxia during upper gastrointestinal endoscopy is caused by sedation [letter].  Endoscopy. 1993;  25 308-309