Correlation Between Bedside Anatomical Indicators and Lifting Force and Glottic Exposure Under Different Video Laryngoscopy Techniques

NCT07846748 | Not Yet Recruiting

• 1 other identifier: [2026]YX172
• Study Type: observational
• Target: 200
• Locations: 0 countries
• Sites: N/A

Brief Summary

This single-center prospective observational study plans to enroll 196 patients undergoing elective general anesthesia. The study aims to investigate the correlation between preoperative bedside anatomical indicators (including modified Mallampati classification, upper lip bite test, mouth opening, head circumference, and thyromental distance) and the peak lifting force applied during video laryngoscopy, as well as the degree of glottic exposure (POGO score). The study will also evaluate the potential benefit of the direct epiglottis elevation technique in specific anatomical subgroups. After anesthesia induction, the same anesthesiologist will perform video laryngoscopy using two distinct techniques in a fixed sequence: the indirect (vallecula) method and the direct (subepiglottic) method. Peak lifting force will be quantitatively measured in real-time using a resistive thin-film pressure sensor attached to the laryngoscope blade. The primary outcomes are the POGO scores and peak lifting forces under both techniques. The secondary outcome includes the change in POGO score (ΔPOGO) between techniques. The study will provide quantitative evidence regarding the "anatomy-force-view" relationship and aid in individualized clinical decision-making for video laryngoscopy intubation.

Conditions

Difficult Airway; Intubation, Intratracheal

Outcome Measures

Primary Outcomes (4)

• Peak Lifting Force with Direct Epiglottis Elevation

  Peak lifting force (gf) measured by a resistive thin-film pressure sensor attached to the video laryngoscope blade during the direct (subepiglottic) technique.

  Perioperative

• Peak Lifting Force with Indirect Epiglottis Elevation

  Peak lifting force (gf) measured by a resistive thin-film pressure sensor attached to the video laryngoscope blade during the indirect (vallecula) technique.

  Perioperative

• POGO Score with Indirect Epiglottis Elevation

  Percentage of Glottic Opening (POGO) score assessed via video laryngoscopy using the indirect (vallecula) technique. The scale ranges from 0% to 100%, where higher scores indicate better visualization of the glottis (better outcome).

  Perioperative

• POGO Score with Direct Epiglottis Elevation

  Percentage of Glottic Opening (POGO) score assessed via video laryngoscopy using the direct (subepiglottic) technique. The scale ranges from 0% to 100%, where higher scores indicate better visualization of the glottis (better outcome).

  Perioperative

Secondary Outcomes (2)

• Delta POGO (ΔPOGO)

  Perioperative

• Incidence of Difficult Glottic Exposure

  Perioperative

Study Arms (1)

Patients Undergoing Video Laryngoscopy

Adult patients scheduled for elective general anesthesia requiring orotracheal intubation under video laryngoscopy guidance. All participants will undergo both indirect and direct epiglottis elevation techniques in a fixed sequence.

Procedure: Direct Epiglottis Elevation (Subepiglottic Method)

Interventions

Direct Epiglottis Elevation (Subepiglottic Method) PROCEDURE

Video laryngoscopy blade tip advanced past the vallecula and placed under the laryngeal surface of the epiglottis to directly lift it.

Patients Undergoing Video Laryngoscopy

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adult patients aged 18 to 75 years with ASA physical status I to III who are scheduled for elective surgery under general anesthesia requiring orotracheal intubation under video laryngoscopy guidance. Patients with known difficult airway, facial or neck abnormalities affecting landmark palpation, limited mouth opening (\< 2.0 cm), or edentulism are excluded.

You may qualify if:

• \- Age 18 to 75 years
• ASA physical status I to III
• Scheduled for orotracheal intubation under video laryngoscopy guidance
• Written informed consent obtained

You may not qualify if:

• Known history of difficult airway or anticipated need for awake intubation
• Facial or neck trauma, burns, or surgical history affecting palpation of anatomical landmarks
• Temporomandibular joint ankylosis or mouth opening \< 2.0 cm
• Edentulous patients

Sponsors & Collaborators

• Second Hospital of Shanxi Medical University: lead

Central Study Contacts

Jin

CONTACT

+86-18235572836; 1806442507@qq.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: professor

Study Record Dates

• First Submitted: September 16, 2026
• First Posted: September 29, 2026
• Study Start: October 1, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): June 1, 2027
• Last Updated: September 29, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share