PARAtracheal vs CRIcoid Pressure on GLIttic DEformation (PARAGLIDE)

Official title

Comparison of Left Paratracheal Versus Cricoid Pressure on Glottic Visualization During Videolaryngoscopy: A Randomized Crossover Study

Overview

This randomized crossover study evaluates the effects of left paratracheal pressure, cricoid pressure, and no pressure on glottic visualization during videolaryngoscopy in adult surgical patients. The primary endpoint is the Percentage of Glottic Opening (POGO) score assessed by blinded video review. Secondary endpoints include anatomical measures (glottic surface area, vertical and horizontal displacement of the glottic plane) and clinical outcomes (first-pass success, first-pass success without desaturation \<90%, intubation time, Intubation Difficulty Scale, hypoxemia, hemodynamic events, airway trauma, and postoperative sore throat or dysphonia). All outcomes are collected from routine anesthetic practice and video analysis, with no additional procedures.

Detailed description

This randomized crossover trial will compare three laryngoscopy conditions (no pressure, cricoid pressure, left paratracheal pressure) in adult surgical patients requiring general anesthesia with tracheal intubation. Each patient undergoes all three conditions in random order, with the intubation performed using the maneuver chosen by the operator. Anatomical outcomes (POGO, glottic surface area, vertical and horizontal displacement of the glottic plane) will be assessed from video recordings by blinded evaluators. Clinical outcomes (first-pass success, composite success without desaturation \<90%, intubation time, IDS, hypoxemia, hemodynamic changes, airway trauma, sore throat, dysphonia) will be collected from routine anesthetic records and PACU assessments.

Statistical Analysis Plan:

POGO: mixed-effects repeated measures model with patient as random effect, maneuver as fixed effect, adjusted for operator, BMI, and Mallampati.

Anatomical outcomes: analyzed similarly with mixed models and planned contrasts (LPP vs CP).

Clinical outcomes: analyzed as-treated, using logistic or linear regression with adjustments for baseline factors and operator as random effect.

Mediation analysis will evaluate whether improvements in POGO explain clinical benefits (first-pass success, intubation time).

Significance level set at α=0.05 (two-sided), with exploratory outcomes interpreted without multiplicity correction.

Missing data (e.g., unusable videos, missing sore throat scores) will be reported; complete-case analysis will be primary, sensitivity analysis considered if \>5% missing.

Interventions

• Procedure Cricoid Pressure (30 N)
  Manual application of posterior pressure on the cricoid cartilage at a standardized force of 30 newtons. The pressure is applied by a trained operator using one or two fingers, with the goal of compressing the esophagus against the cervical spine. The maneuver is performed after induction of general anesthesia and immediately before videolaryngoscopy. A still image of the glottic view is captured during pressure application.
• Procedure Left Paratracheal Pressure (30 N)
  Manual application of pressure to the left paratracheal region, lateral to the trachea and inferior to the thyroid cartilage, at a standardized force of 30 newtons. The pressure is applied by a trained operator using the thumb or fingers. The maneuver is performed after induction of general anesthesia and immediately before videolaryngoscopy. A still image of the glottic view is captured during pressure application.

Primary outcome measures

• Percentage of Glottic Opening (POGO) score [Time frame: During laryngoscopy, before tracheal intubation]

Secondary outcome measures (11)

• Glottic surface area [Time frame: During laryngoscopy, before intubation]
• Vertical Displacement of the Glottic Plane [Time frame: During laryngoscopy, before intubation]
• Horizontal displacement of the glottic plane [Time frame: During laryngoscopy, before intubation]
• First-pass intubation success [Time frame: From laryngoscope insertion to first confirmed capnography]
• Time to intubation [Time frame: From laryngoscope insertion to first confirmed capnography]
• Intubation Difficulty Scale (IDS) [Time frame: During intubation]
• First-attempt success without desaturation < 90% [Time frame: From laryngoscope blade past the incisors until confirmed tracheal intubation (end-tidal CO₂ ≥ 5 mmHg for 3 breaths), typically up to 2 minutes.]
• Hypoxemia [Time frame: From induction until confirmed intubation]
• Hemodynamic events [Time frame: From induction until confirmed intubation]
• Airway trauma [Time frame: Immediately after intubation]
• Postoperative sore throat [Time frame: 30-60 minutes in PACU]

Eligibility criteria

Inclusion criteria

• Age ≥ 18 years
• Scheduled for elective surgery under general anesthesia requiring endotracheal intubation
• ASA physical status I or II
• Normal airway anatomy as assessed by the anesthesiologist (Mallampati I-II, no known or anticipated difficult airway)
• Written informed consent obtained prior to inclusion

Exclusion criteria

• History of difficult intubation or anticipated difficult airway
• Known upper airway anatomical abnormalities (e.g., tumors, tracheal deviation, cervical spine instability)
• BMI > 35 kg/m²
• Gastroesophageal reflux disease or increased aspiration risk
• Pregnancy
• Emergency surgery
• Allergy or contraindication to any anesthetic drugs used
• Inability to provide informed consent

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Crossover

Masking

Single blind

Primary purpose

Treatment

Study locations

Belgium · 1 center

• Clinique Saint-Luc — Bouge

Identifiers

NCT: NCT07004998 · PARAGLIDE

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗