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Point-of-Care Ultrasound: A Review of Ultrasound Parameters for Predicting Difficult Airways
Published on: April 7, 2023
Study on the Ultrasonic Characteristics of the Paraglottic Space at the Glottic Level in Normal Adults
Xiang-Ru Wang1, Hua Wang1, Yue Gao1,2
1Department of Ultrasound, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Objective:
High-frequency ultrasound was used to observe and measure the width of the normal adult glottal-level paraglottic space (PGS).
Methods:
One thousand healthy Han Chinese adults (694 women; 18-79 years) were enrolled between October 2023 and April 2024. PGS ultrasound characteristics were observed, and the width was measured at the midpoint of the anterior, middle, and posterior 1/3 points. The data were stratified by age group and sex. Spearman correlation analysis was used to analyze the correlations between PGS width and sex, age, height, weight, BMI, and BSA.
Results:
The glottic-level PGS is a triangular hyperechoic structure that is narrow in the front and wide in the back of the parathyroid cartilage section. The PGS width reference ranges (5th and 95th percentiles) were as follows: Male: W 1 (0.45-1.16) mm, W 2 (0.55-1.71) mm, W 3 (1.30-2.35) mm; Female: W 1 (0.55-0.95) mm, W 2 (0.90-1.35) mm, W 3 (1.55-2.00) mm. There were no statistically significant differences in W 1, W 2, and W 3 between males and females or between different age groups (all p > 0.05).
Conclusions:
This study summarized normal adult PGS ultrasound characteristics at the glottal level and established references for PGS width, which can provide reference values for clinical practice.
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