Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul 110-744, South Korea.
Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam 463-707, South Korea.
J Clin Anesth. 2013 Aug;25(5):384-387. doi: 10.1016/j.jclinane.2013.01.015. Epub 2013 Aug 17.
To determine whether a radiograph-based formula using the tracheal diameter from a chest radiograph predicted the appropriate endotracheal tube (ETT) size in children, and to compare these results with those produced using age-based formulas.
Retrospective, observational study.
Medical record review.
Data from 537 pediatric patients, aged 3 to 6 years, who underwent orotracheal intubation with an uncuffed ETT, were randomly divided into two datasets: one was used to derive a formula and the other was for validation. A radiograph-based formula was obtained by linear regression modeling between the tracheal diameter at the seventh cervical vertebra (C7) on chest radiography and the appropriate ETT size from the estimation dataset (n=268). The appropriate size was defined as the ETT size when air leak pressure was 10 to 30 cmH2O. The predictive ability of this equation was evaluated using the validation dataset (n=269). The primary outcome was the success rate of the prediction.
The following radiograph-based formula was obtained: ID = 3 + 0.3 × (tracheal diameter at C7). The success rate of the radiograph-based formula was 57%, which is higher than the 32% (P < 0.001) of the standard age-based formula (ID = 4 + age/4) or 43% (P = 0.002) of Penlington's formula (ID = 4.5 + age/4). An underestimation of the actual tracheal size occurred in 65% of cases using the age-based formulas, but in only 19% with the radiograph-based formula (P < 0.001).
The radiograph-based formula may be useful for predicting the appropriate ETT size in children aged 3 to 6 years.
确定基于胸片的气管直径公式是否能预测儿童合适的气管内导管（ETT）大小，并与基于年龄的公式进行比较。
回顾性观察性研究。
病历回顾。
537 名年龄在 3 至 6 岁的小儿患者接受经口气管插管，使用无套囊 ETT，将其随机分为两个数据集：一个数据集用于推导公式，另一个数据集用于验证。通过线性回归模型，在胸片上第七颈椎（C7）处的气管直径与估计数据集（n=268）中合适的 ETT 大小之间建立了基于胸片的公式。合适的大小定义为当空气泄漏压力为 10 至 30cmH2O 时的 ETT 大小。使用验证数据集（n=269）评估该方程的预测能力。主要结果：得出以下基于胸片的公式：ID=3+0.3×（C7 处气管直径）。基于胸片的公式的成功率为 57%，高于标准年龄公式（ID=4+年龄/4）的 32%（P<0.001）或 Penlington 公式（ID=4.5+年龄/4）的 43%（P=0.002）。使用年龄公式会低估实际气管大小，发生率为 65%，而使用基于胸片的公式则为 19%（P<0.001）。
基于胸片的公式可能有助于预测 3 至 6 岁儿童合适的 ETT 大小。
