Newborn Research, The Royal Women's Hospital, Melbourne, Australia.
The Murdoch Childrens Research Institute, Melbourne, Australia.
Arch Dis Child Fetal Neonatal Ed. 2018 Jul;103(4):F364-F369. doi: 10.1136/archdischild-2017-313039. Epub 2017 Aug 17.
Umbilical arterial catheter (UAC) insertion is a common procedure in the neonatal intensive care unit (NICU). Correct placement of the tip of the UAC at first attempt minimises handling of the infant and reduces the risk of infection and complications. We aimed to determine the accuracy of 11 published formulae to guide UAC placement.
This was a one-year prospective observational study in a tertiary NICU. Clinicians used their preferred formula for UAC insertion, with X-rays performed immediately post-procedure to check the tip position. Birth weight and measurements included in the 11 formulae were recorded within 48 hours. The gold standard insertion distance was defined as the distance from the abdominal wall to the mid-descending aorta, at T8 level on X-ray (range T6-T10). Insertion length using the 11 formulae was calculated and compared with this gold standard distance.
One hundred and three infants were included, with median (IQR) gestational age and weight of 28 (26-33.5) weeks and 980 (780-2045) g, respectively. The predicted value of the 11 formulae to place the UAC in correct position ranged from 51.0% to 73.8%. Formulae that involved direct body part measurements showed the highest predicted success rates, smallest mean difference from T8 and narrowest limits of agreement using the Bland-Altman method.
Success rates for accurate UAC placement are highest when formulae that involve body measurements are used. However, even the most accurate method would result in more than 25% of UACs needing manipulation to achieve an optimal position.
脐动脉导管（UAC）插入是新生儿重症监护病房（NICU）中的常见操作。首次尝试时将尖端正确放置在 UAC 中可以最大程度地减少对婴儿的处理，并降低感染和并发症的风险。我们旨在确定 11 种已发表公式指导 UAC 放置的准确性。
这是一项为期一年的前瞻性观察性研究，在三级 NICU 中进行。临床医生使用他们首选的 UAC 插入公式，在操作后立即进行 X 射线检查以检查尖端位置。在 48 小时内记录 11 个公式中包含的出生体重和测量值。黄金标准插入距离定义为从腹壁到 T8 水平降主动脉的距离（X 射线范围 T6-T10）。使用 11 个公式计算插入长度，并将其与该黄金标准距离进行比较。
共纳入 103 例婴儿，中位（IQR）胎龄和体重分别为 28（26-33.5）周和 980（780-2045）g。11 个公式中预测 UAC 正确位置的数值范围为 51.0%至 73.8%。涉及直接身体部位测量的公式显示出最高的预测成功率，与 T8 的平均差异最小，Bland-Altman 方法的协议范围最窄。
当使用涉及身体测量的公式时，UAC 放置的准确性最高。但是，即使是最准确的方法也会导致超过 25%的 UAC 需要操作以达到最佳位置。
