The accuracy of ultrasound to predict endotracheal tube size for pediatric patients with congenital scoliosis

Abstract

Background: Ultrasonography has been used for prediction the endotracheal tube(ETT) size through measuring the cricoid cartilage diameter. The aim of this study was to determine the accuracy of ultrasound to predict ETT size for pediatric patients with congenital scoliosis.Methods:Fifty pediatric patients underwent scoliosis surgery were included in the study. According to the position of scoliosis, patients were divided into three groups: Group C (cervical lateral bending); Group T ( thoracic scoliosis); and Group L (lumbar scoliosis). For all participants, the transverse diameter of the cricoid cartilage was measured with ultrasonography and the initial ETT size was chosen according to the measurements, then the leak test was used to determine the best‑fit ETT size. In each group, the ETT size measured by ultrasound and the best‑fit ETT size were compared using Bland-Altman analysis and linear regression analysis.Results: There was a strong correlation between the best‑fit ETT size and the ETT size predicted by ultrasound in Group T (r=0.93, p<0.001) and Group L(r=0.95, p<0.001) and a moderate correlation in Group C(r=0.83, p<0.001). Bland-Altman analysis show that the ETT size was over estimated by ultrasound in pediatric patients with cervical lateral bending.Conclusion: Ultrasound is a reliable tool to predict ETT size for pediatric patients with thoracic scoliosis and lumbar scoliosis. However, compared to what was predicted by ultrasonography, pediatric patients with cervical lateral bending need a smaller sized ETT.

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

“…Some studies have used ultrasonography to predict the feasibility of endotracheal intubation by measuring the cricoid cartilage diameter [13][14][15][16]. 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 the past, X-ray imaging was used to measure tracheal diameter [12]. 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].…”