Impact of Nasal Mask Versus Nasal Cannula Oxygenation on Hypoxemia in Gastrointestinal Endoscopy: A Brain Function Monitoring (SedLine)-Guided Randomized Controlled Trial (NAMSHIC) (NAMSHIC)

Comparison of the Efficacy of Nasal Mask and Nasal Cannula Oxygenation During Gastrointestinal Endoscopic Procedures Performed Under Target-Controlled Propofol Infusion Anesthesia With Brain Function Monitoring (SedLine): A Randomized Controlled Trial

This randomized controlled trial compared the efficacy of a nasal mask versus a standard nasal cannula for oxygen delivery during gastrointestinal endoscopic procedures performed under target controlled propofol infusion anesthesia with SedLine brain function monitoring. Hypoxemia during procedural sedation is a common and clinically relevant event, especially during upper endoscopy and combined procedures. The study aimed to determine whether nasal mask oxygenation reduces hypoxemia compared with nasal cannula oxygenation when sedation depth is guided with electroencephalography based monitoring.

Eligible adult patients undergoing gastrointestinal endoscopic procedures were randomly assigned to receive oxygen either via a nasal mask or via a nasal cannula. Oxygen was administered at a fixed flow rate according to the study protocol. Sedation was provided with target controlled propofol infusion, and SedLine monitoring was used to guide sedation depth throughout the procedure.

The primary outcome was the occurrence of hypoxemia, defined as peripheral oxygen saturation at or below 90 percent. Secondary outcomes included severe hypoxemia, duration of hypoxemia, lowest peripheral oxygen saturation value, need for airway interventions, other adverse events during the procedure, procedure time, recovery time, and operator satisfaction ratings. The study has been completed.

Study Overview

• Status: Completed
• Conditions: Hypoxemia; Conscious Sedation
• Intervention / Treatment: Device: Nasal Mask Oxygenation; Device: Nasal Cannula Oxygenation

Detailed Description

This study was a prospective randomized controlled trial designed to compare two oxygen delivery approaches during gastrointestinal endoscopic procedures performed under target controlled propofol infusion anesthesia with SedLine brain function monitoring. The main objective was to evaluate whether nasal mask oxygenation provides better protection against hypoxemia than standard nasal cannula oxygenation when sedation depth is actively guided with electroencephalography based monitoring.

Adult patients scheduled for gastrointestinal endoscopic procedures were assessed for eligibility and enrolled after appropriate ethical approval and informed consent procedures in accordance with local regulations. Participants were randomly assigned to one of two groups. In the nasal mask group, oxygen was delivered using a nasal mask device. In the nasal cannula group, oxygen was delivered using a standard nasal cannula. Oxygen flow was administered as specified in the protocol. Sedation for all patients was provided with target controlled propofol infusion. SedLine brain function monitoring was used to guide and standardize sedation depth during the procedure to reduce variability related to over sedation or under sedation.

The primary outcome was hypoxemia, defined as peripheral oxygen saturation at or below 90 percent. Secondary outcomes included severe hypoxemia, duration of hypoxemia, the minimum peripheral oxygen saturation recorded, need for airway support or rescue interventions, procedure related adverse events such as cough, hiccup, nausea, vomiting, reflux, aspiration, and laryngospasm, total procedure time, recovery time, and satisfaction ratings by the anesthesiologist and the endoscopist. All outcomes were assessed during the procedure and the immediate recovery period based on standardized definitions in the study protocol. The study has been completed, and the collected data are intended to support evaluation of the comparative effectiveness and safety of nasal mask versus nasal cannula oxygenation in this clinical setting.

• Study Type: Interventional
• Enrollment (Actual): 600
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Istanbul, Turkey (Türkiye)
    • University of Health Sciences Sultan Abdulhamid Han Training and Research Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adults aged 18 years or older.

Scheduled for gastrointestinal endoscopic procedures (upper endoscopy and or colonoscopy) under propofol sedation using target controlled infusion with SedLine monitoring.

American Society of Anesthesiologists (ASA) physical status I to III.

Provided written informed consent.

Exclusion Criteria:

• Refusal or inability to provide informed consent.

Known allergy or contraindication to propofol or study related materials.

Severe cardiorespiratory instability or conditions judged by the investigator to increase procedural risk.

Pregnancy.

Requirement for tracheal intubation or general anesthesia at the outset of the procedure.

Significant anatomic or clinical factors precluding use of the assigned oxygen delivery device.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Nasal Mask Oxygenation; Oxygen was delivered via a nasal mask during gastrointestinal endoscopic procedures performed under target controlled propofol infusion with SedLine brain function monitoring.	Device: Nasal Mask Oxygenation; Oxygen supplementation delivered via a nasal mask at the protocol specified flow rate during the procedure.
Active Comparator: Nasal Cannula Oxygenation; Oxygen was delivered via a standard nasal cannula during gastrointestinal endoscopic procedures performed under target controlled propofol infusion with SedLine brain function monitoring.	Device: Nasal Cannula Oxygenation; Oxygen supplementation delivered via a standard nasal cannula at the protocol specified flow rate during the procedure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hypoxemia	Occurrence of hypoxemia defined as peripheral oxygen saturation (SpO2) ≤ 90% during the procedure	During the endoscopic procedure and immediate recovery period (from start of sedation to discharge from the recovery area).

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Severe hypoxemia	SpO2 ≤ 75% at any time, or SpO2 ≤ 90% lasting ≥ 60 seconds.	During the endoscopic procedure and immediate recovery period
Duration of hypoxemia	Total duration (seconds) with SpO2 ≤ 90%.	During the endoscopic procedure and immediate recovery period.
Minimum SpO2	Lowest SpO2 recorded during the procedure.	During the endoscopic procedure
Need for airway interventions	Any airway rescue or supportive intervention required (e.g., airway repositioning, jaw thrust, increased oxygen, mask ventilation, or other emergency airway management).	During the endoscopic procedure and immediate recovery period
Procedure-related adverse events	Cough, hiccup, nausea, vomiting, reflux, aspiration, laryngospasm, and other adverse events.	During the endoscopic procedure and immediate recovery period.
Procedure time	Total procedure duration (minutes).	During the procedure.
Recovery time	Time from end of procedure to readiness for discharge from recovery (minutes).	Immediately after the procedure
Satisfaction ratings	Anesthesiologist and endoscopist satisfaction assessed using a 0-100 Numeric Rating Scale, where 0 = least satisfied and 100 = most satisfied (higher scores indicate greater satisfaction)	mmediately after the procedure, during recovery (same day).

Collaborators and Investigators

• Sponsor: Sultan Abdulhamid Han Training and Research Hospital, Istanbul, Turkey

Study record dates

Study Major Dates

• Study Start (Actual): January 6, 2025
• Primary Completion (Actual): August 26, 2025
• Study Completion (Actual): November 15, 2025

Study Registration Dates

• First Submitted: January 7, 2026
• First Submitted That Met QC Criteria: March 25, 2026
• First Posted (Actual): March 30, 2026

Study Record Updates

• Last Update Posted (Actual): March 30, 2026
• Last Update Submitted That Met QC Criteria: March 25, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Propofol; Pulse Oximetry; Oxygenation; Gastrointestinal Endoscopy; Nasal Cannula; Target-Controlled Infusion; SedLine; Nasal Mask
• Additional Relevant MeSH Terms: Signs and Symptoms, Respiratory; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Hypoxia
• Other Study ID Numbers: 2024/392 (Other Identifier: SBÜ Sancaktepe Şehit Prof. Dr. Ilhan Varank Training and Research Hospital Scientific Research Ethics Committee)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No