Ultrasonography measurement of glottic transverse diameter and subglottic diameter to predict endotracheal tube size in children: a prospective cohort study

Abstract

We aimed to determine the correlation between mid-glottic transverse diameter/subglottic diameter and outer diameter of endotracheal tube (ETT) by ultrasonography in children. Ninety-five patients aged 1–8 years who underwent general anesthesia were included. Ultrasonography of glottic/subglottic transverse diameter was performed by two investigators after patients were anesthetized and when the train of four showed ≤ 4. The subglottic diameter was measured at the mid cricoid cartilage. The mid-glottic transverse diameter was measured at the mid-point of true vocal fold triangle whereas the distance between arytenoids was considered as the glottic transverse diameter. Linear regression models and correlation coefficients (r) were used to determine the best formula of glottic/subglottic transverse diameter to predict the outer diameter of ETT. The predicted outer diameter of ETT formula for subglottic diameter, mid-glottic transverse diameter, and glottic transverse diameter were 5.7 + (subglotticmm/3) with an r of 0.45, 5.5 + (midglotticmm/2) with an r of 0.47, and 5.7 + (glotticmm/4) with an r of 0.46, respectively. The correlation between subglottic diameter and mid-glottic transverse diameter was 0.50. Subglottic/mid-glottic/glottic transverse diameter formulae had moderate correlations with the outer diameter of ETT. The glottic/mid-glottic transverse diameter can be used alternatively to predict the ETT size.Trial registration: Thai Clinical Trial Registry: TCTR20191022002 Registered 22/10/2019—Prospectively registered, https://www.thaiclinicaltrials.org/# TCTR20191022002.

Analysis of Risk Factors of Potentially Difficult Endotracheal Intubation: A Retrospective Observational Study of 154 Patients with Scoliosis at a Single Center in China

“…The glottic entrance is usually the narrowest area of the trachea [17,18]. In a prospective study involving 95 children, a correlation was found between the glottis diameter measured by ultrasonography and endotracheal intubation size [17], but generalizability of that study is confined to only healthy children with no previous airway abnormalities.…”

“…Hao et al used ultrasonography to measure the transverse diameter of cricoid cartilage in 50 patients with congenital scoliosis to predict the size of endotracheal intubation, but the measurement was biased due to cone rotation [16]. The glottic entrance is usually the narrowest area of the trachea [17,18]. In a prospective study involving 95 children, a correlation was found between the glottis diameter measured by ultrasonography and endotracheal intubation size [17], but generalizability of that study is confined to only healthy children with no previous airway abnormalities.…”

“…Recent studies have used ultrasonography to predict the feasibility of endotracheal intubation by measuring the cricoid cartilage diameter [13][14][15][16]. However, the glottis is usually located in the narrowest cross-section in the tracheal, which is considered the limiting factor during intubation [17,18]. Research to date has not yet measured glottic parameters in patients with scoliosis, and no studies have determined the condition and risk factors of difficult intubation in various types of scoliosis patients.…”

Long-term stimulation by implanted pacemaker enables non-atrophic treatment of bilateral vocal fold paresis in a human-like animal model

“…The left side of three animals required higher amplitudes of 3.5 mA, 5 mA and 6 mA for a maximal glottal opening. In DC04, each stimulation lasted for 1.7 s followed by a pause of 2.6 s. In DC07 the stimulation lasted for 3.0 s, followed by a pause of 1.3 s. Ultrasound was used once a week to observe the movement of the anterior parts of the vocal folds and the arytenoid cartilages 60 , 61 to confirm that the PCA was still opening the vocal folds. If this was not the case, the amplitude was increased to achieve sufficient movement and, if necessary, the position and condition of the electrodes were checked by X-ray in the awake, standing animal.…”

The Effect of the Ultrasonography Measurement Method and the Conventional Measurement Method Used in Endotracheal Tube Size Selection in the Pediatric Patient Group on Postextubation Complications and Patient Recovery

“…The issue of determining the ETT diameter to be used in the pediatric patient group is still controversial today. Due to anatomical, structural, and racial differences, this situation is tried to be solved by developing various formulas including height, weight, and age of the child in the literature [ 3 , 7 , 8 ]. Generally, the COLE formula (internal diameter (mm) = (age/4) +4) is used for this purpose [ 3 ].…”