Effect of Lateral Positions on the Shape of Upper Airway

Completed

• Conditions: Position; Morphology; Airway Remodeling; Patency; Radiography in Otolaryngology
• Interventions: Behavioral: MRI scanning first at supine position and then turn into lateral position

• Registration Number: NCT06236971
• Lead Sponsor: First Affiliated Hospital of Zhejiang University

Brief Summary

The severity and frequency of respiratory events is increased in the supine body posture compared with the lateral position in emergency, difficult airway patients. The mechanism responsible is not clear but may relate to the effect of position on upper airway shape and size. 3D finite element model of upper airway filling based on MRI image reconstruction can effectively reflect the anatomy of the upper airway. This study compared the effect of body position on upper airway shape and size in individuals with lateral position among sedated subjects.

Detailed Description

Anesthesiologists may encounter situations in which a accidental loss of airway patency occurs in patients in a lateral patient position during surgery. Intubation is required in the lateral position in cases of oropharyngeal bleeding to reduce the risk of aspiration, or in airway management in some patients with limited posture. The severity and frequency of respiratory events is increased in the supine body posture compared with the lateral position in emergency, difficult airway patients. The mechanism responsible is not clear but may relate to the effect of position on upper airway shape and size secondary to gravitational effects. Lateral positioning decreases upper airway obstruction in sleeping individuals, children breathing spontaneously, and adults during general anesthesia. The mechanical upper airway properties may become the dominant factor governing upper airway collapsibility during sedation due to the significant depression of consciousness and the impairment of neural mechanisms controlling compensatory neuromuscular responses. Anesthesiologists and surgeons who are responsible for airway management during procedures under sedation and the perioperative period should be well versed with the physiological and pathophysiological mechanisms affecting upper airway patency. 3D finite element model of upper airway filling based on MRI image reconstruction can effectively reflect the anatomy of the upper airway.

The primary aim of this study was to determine the changes in upper airway shape and size that occur when sedated, spontaneously breathing adults are placed in the lateral position. These findings may provide new guidance for the evaluation and prediction of difficult airway during clinical anesthesia.

Study Timeline

• Study First Submitted: 2024-01-13
• Study First Submitted QC: 2024-01-24
• Study First Posted: 2024-02-01
• Study Start: 2024-02-05
• Primary Completion: 2024-03-29
• Study Completion: 2024-03-29
• Status Verified: 2024-05
• Last Update Submitted: 2024-05-24
• Last Update Posted: 2024-05-28

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 31

Inclusion Criteria

1. Subjects aged over than 18 years and less than 100 years
2. The American Society of Anesthesiologists (ASA) score was grade I to II
3. There was no serious cardiopulmonary disease

Exclusion Criteria

1. Unable to maintain oxygenation before or during the examination and requiring intervention
2. Those with preoperative arrhythmia requiring intervention
3. Thosewith severe hematological diseases, severe metabolic diseases, severe liver and kidney organ insufficiency
4. Those do not consent to participate in the study

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
MRI scanning	MRI scanning first at supine position and then turn into lateral position	The subjects are receiving MRI scanning first in the supine position, and then in the lateral position. The field of view was determined from the length and girth of each patient's head, at least including the skull base to the level of tracheal bifurcation.

Primary Outcome Measures

Name	Time	Method
minimum cross-sectional area (MCSA)	through study completion, an average of 2 months	minimum cross-sectional area (MCSA) of upper airway-related sagittal, cross-sectional, and coronal planes
lateral diameters	through study completion, an average of 2 months	lateral diameters
minimum anteroposterior	through study completion, an average of 2 months	minimum anteroposterior diameters
pharyngeal volume	through study completion, an average of 2 months	pharyngeal volume

Secondary Outcome Measures

Name	Time	Method
Change of heart rates (HR) in beats per minute	before examination, immediately after examination at supine position, immediately before examination at lateral position, immediately after examination at lateral position	compared the change of HR in beats per minute between different position
three-dimensional geometrical modeling of the upper airway	through study completion, an average of 2 months	three-dimensional geometrical modeling of the upper airway by MATALAB software
Change of oxygenation (SpO2, %)	before examination, immediately after examination at supine position, immediately before examination at lateral position, immediately after examination at lateral position	compared the change of SpO2 (%)
Change of respiratory rates (RR) in respirations per minute	before examination, immediately after examination at supine position, immediately before examination at lateral position, immediately after examination at lateral position	compared the change of RR in respirations per minute between different position

Trial Locations

Locations (1)

Tongde Hospital of Zhejiang Province; 🇨🇳 Hangzhou, Zhejiang, China