Obesity Surgery

, Volume 30, Issue 1, pp 238–243 | Cite as

Unsedated Transnasal Endoscopy for Preoperative Examination of Bariatric Patients: a Prospective Study

  • Amaury Teixeira XavierEmail author
  • Arthur V. Alvares
  • Prasad G. Iyer
  • Vitor N. Arantes
Original Contributions



Esophagogastroduodenoscopy is a preoperative examination commonly required for candidates to bariatric surgery (BS). Overweight individuals have a greater risk of cardiorespiratory complications during endoscopy under sedation. This study aimed to investigate the feasibility, tolerance, and cardiovascular stress of transnasal endoscopy (TNE) without sedation in obese patients eligible for BS.


This prospective study enrolled obese adult patients with indication for BS that consented to undergo unsedated preoperative TNE. All examinations were carried out in an outpatient center. The outcomes assessed were endoscopic findings, procedural success, patients’ tolerance according to a visual analogic scale, cardiovascular stress estimated by double product (i.e., systolic blood pressure × heart rate) and adverse events. Statistical analyses were used to compare each patient’s double product among different examination periods.


Ninety-four patients (77.6% female) completed the study, with an average body mass index (BMI) of 53 kg/m2 (range, 35–73.4 kg/m2). There were 63 super-obese individuals (67%), with BMI > 50 kg/m2. In 93 patients (98.9%), unsedated TNE was successfully completed up to the second part of the duodenum. TNE failed in one patient. Tolerance was rated as excellent or good in 95.7%. Minimal cardiovascular stress was noted in obese individuals, whereas the double product remained stable throughout the procedure in super-obese patients. Three patients (3.2%) had self-limited epistaxis.


Unsedated TNE for preoperative endoscopic evaluation of obese patients is feasible, safe, and well tolerated and should be preferentially considered when examining super-obese patients.


Transnasal endoscopy Obesity Endoscopy without sedation 



The authors would like to thank Enago ( for the English language review.

The authors would like to thank the Federal University of Minas Gerais and Clinical Hospital for recruiting patients.

Author’s Contribution

Amaury T. Xavier, MS: Drafting of the manuscript

Arthur V. Alvares: Drafting of the manuscript

Prasad G. Iyer, M.D: Drafting and critical revision of the manuscript

Vitor N. Arantes, M.D: Drafting and critical revision of the manuscript

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Ethical Approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed Consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Endoscopy Unit, Alfa Institute of Gastroenterology, Clinics HospitalFederal University of Minas GeraisBelo HorizonteBrazil
  2. 2.Instituto Alfa de GatroenterologiaUniversidade Federal de Minas Gerais – MedicineBelo HorizonteBrazil
  3. 3.Endoscopy UnitMilitary Hospital of Minas GeraisBelo HorizonteBrazil
  4. 4.Division of Gastroenterology and HepatologyMayo ClinicRochesterUSA

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