Effect of Lateral Positions on the Shape of Upper Airway

Effect of Lateral Positions on the Shape of Upper Airway Under Sedation

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.

Study Overview

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

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 Type: Observational
• Enrollment (Estimated): 30

Contacts and Locations

• Study Contact: Name: Hui Ye, M.D.; Phone Number: 15267048716; Email: yehui@zju.edu.cn

Study Locations

• China
  • Zhejiang
    • Hangzhou, Zhejiang, China, 310000
      • Recruiting
      • Tongde Hospital of Zhejiang Province
      • Contact: Hui Ye, M.D.; Phone Number: 15267048716; Email: yehui@zju.edu.cn
      • Principal Investigator: Xiangming Fang, M.D.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Probability Sample

Study Population

Healthy subjects aged over 18 years old, ASA 1~II without serious cardiopulmonary disease, scheduled for magnetic resonance imaging scan in the supine position and followed lateral position at a tertiary hospital from January 2024 to February 2024 were enrolled in this study.

Description

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 Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
MRI scanning; 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.	Behavioral: MRI scanning first at supine position and then turn into lateral position; Magnetic resonance imaging was used to scan the upper airway of sedated subjects, first at supine position and then turn into lateral position.

What is the study measuring?

Primary Outcome Measures

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

Secondary Outcome Measures

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

Collaborators and Investigators

• Sponsor: First Affiliated Hospital of Zhejiang University
• Collaborators: Zhejiang Provincial Tongde Hospital
• Investigators: Principal Investigator: Xiangming Fang, M.D., The First Affiliated Hospital School of MedicineZhejiang University

Publications and helpful links

General Publications

• Litman RS, Weissend EE, Shrier DA, Ward DS. Morphologic changes in the upper airway of children during awakening from propofol administration. Anesthesiology. 2002 Mar;96(3):607-11. doi: 10.1097/00000542-200203000-00016.
• Lin CY, Chen CN, Kang KT, Hsiao TY, Lee PL, Hsu WC. Ultrasonographic Evaluation of Upper Airway Structures in Children With Obstructive Sleep Apnea. JAMA Otolaryngol Head Neck Surg. 2018 Oct 1;144(10):897-905. doi: 10.1001/jamaoto.2018.1809.
• Campos LD, Trindade IEK, Trindade SHK, Pimenta LAF, Kimbell J, Drake A, Marzano-Rodrigues MN, Trindade-Suedam IK. Effects of 3D Airway Geometry on the Airflow of Adults with Cleft Lip and Palate and Obstructive Sleep Apnea: A Functional Imaging Study. Sleep Sci. 2023 Nov 22;16(4):e430-e438. doi: 10.1055/s-0043-1776868. eCollection 2023 Dec.
• Chen W, Ma L, Shao J, Bi C, Xie Y, Zhao S. Morphological specificity analysis of an image-based 3D model of airway filling in a difficult airway. BMC Anesthesiol. 2022 Nov 3;22(1):336. doi: 10.1186/s12871-022-01880-6.
• Martinez A, Muniz AL, Soudah E, Calvo J, Suarez AA, Cobo J, Cobo T. Physiological and geometrical effects in the upper airways with and without mandibular advance device for sleep apnea treatment. Sci Rep. 2020 Mar 24;10(1):5322. doi: 10.1038/s41598-020-61467-4.
• Dollinger M, Jakubass B, Cheng H, Carter SJ, Kniesburges S, Aidoo B, Lee CH, Milstein C, Patel RR. Computational fluid dynamics of upper airway aerodynamics for exercise-induced laryngeal obstruction: A feasibility study. Laryngoscope Investig Otolaryngol. 2023 Aug 19;8(5):1294-1303. doi: 10.1002/lio2.1140. eCollection 2023 Oct.
• Li H, Wang W, Lu YP, Wang Y, Chen LH, Lei LP, Fang XM. Evaluation of Endotracheal Intubation with a Flexible Fiberoptic Bronchoscope in Lateral Patient Positioning: A Prospective Randomized Controlled Trial. Chin Med J (Engl). 2016 Sep 5;129(17):2045-9. doi: 10.4103/0366-6999.189069.
• Hyldmo PK, Vist GE, Feyling AC, Rognas L, Magnusson V, Sandberg M, Soreide E. Is the supine position associated with loss of airway patency in unconscious trauma patients? A systematic review and meta-analysis. Scand J Trauma Resusc Emerg Med. 2015 Jul 1;23:50. doi: 10.1186/s13049-015-0116-0.
• Litman RS, Wake N, Chan LM, McDonough JM, Sin S, Mahboubi S, Arens R. Effect of lateral positioning on upper airway size and morphology in sedated children. Anesthesiology. 2005 Sep;103(3):484-8. doi: 10.1097/00000542-200509000-00009.

Study record dates

Study Major Dates

• Study Start (Estimated): January 28, 2024
• Primary Completion (Estimated): March 31, 2024
• Study Completion (Estimated): March 31, 2024

Study Registration Dates

• First Submitted: January 13, 2024
• First Submitted That Met QC Criteria: January 24, 2024
• First Posted (Estimated): February 1, 2024

Study Record Updates

• Last Update Posted (Estimated): February 1, 2024
• Last Update Submitted That Met QC Criteria: January 24, 2024
• Last Verified: January 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathological Conditions, Anatomical; Airway Remodeling
• Other Study ID Numbers: airway

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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