Introduction Less-invasive surfactant administration (LISA) under continuous positive airway pressure is increasingly used for the treatment of neonatal respiratory distress. Different procedures are described, but data on the optimal catheter insertion depth are sparse. Objective To generate data for recommending an optimal catheter insertion depth in LISA. Methods We examined 112 anterior–posterior chest X-rays from intubated infants and determined the carina’s vertebral projection, whenever possible. After that, distances between the middle of cervical vertebra 4 (C4) and thoracic vertebra 2 and the middle of C4 to thoracic vertebra 3, respectively, were measured. Results were plotted against infant’s weight. Results A weight-based chart and recommendations for the optimal intratracheal catheter position in infants with a body weight between 350 and 4000 g were created. Conclusions Generated data offer standardisation and may thus help to find a balance between risk of surfactant reflux and unilateral surfactant administration. All data relevant to this data analysis are included in the article or uploaded as supplemental information.

中文翻译：

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微创表面活性剂给药中的导管插入深度

简介 持续气道正压下的微创表面活性剂给药 (LISA) 越来越多地用于治疗新生儿呼吸窘迫。描述了不同的程序，但关于最佳导管插入深度的数据很少。目的 生成用于推荐 LISA 中最佳导管插入深度的数据。方法 我们检查了 112 例插管婴儿的前后胸部 X 光片，并尽可能确定隆突的椎体投影。之后，分别测量颈椎4（C4）中部和胸椎2之间以及C4中部到胸椎3之间的距离。将结果与婴儿体重作图。结果 为体重在 350 至 4000 g 之间的婴儿创建了基于体重的图表和最佳气管内导管位置建议。结论 生成的数据提供了标准化，因此可能有助于在表面活性剂反流风险和单侧表面活性剂给药之间找到平衡。与此数据分析相关的所有数据都包含在文章中或作为补充信息上传。