Department of Pediatrics - Elverum, Innlandet Hospital Trust, Elverum, Norway
Department of Clinical Science, University of Bergen, Bergen, Norway.
Arch Dis Child Fetal Neonatal Ed. 2021 Sep;106(5):489-493. doi: 10.1136/archdischild-2020-320761. Epub 2021 Jan 15.
Heart rate (HR) is an important clinical parameter in newborn infants, but normal ranges are poorly defined. Our aim was to establish normal reference ranges and individual variations in HR as obtained by auscultation in healthy term-born infants during the first 24 hours of life.
Observational study.
Single hospital in Norway.
HR was assessed by auscultation for 30 s at 2, 4, 8, 16 and 24 hours of age. Auscultation was validated against ECG recordings.
Healthy term-born infants who were asleep or awake in a quiet resting state.
Construction of percentile curves for resting HR.
The study included 953 infants. The 50th percentile was 126 beats per minute (bpm) at age 2 hours and thereafter 120-122 bpm. The respective 2nd and 98th percentiles were 102 (thereafter 96-100) bpm and 162 (thereafter 150-156) bpm. The mean HR was 5.6 bpm higher when awake than asleep, 4.9 bpm higher when on the mother's chest than in the cot, 1.6 bpm higher in girls than in boys, and increased by 0.5 bpm per 0.1°C increase in rectal temperature. Mode of delivery, meconium staining, birth weight and maternal smoking during pregnancy were of no significance. For each infant, HR varied considerably during the first 24 hours (intraclass correlation 0.21 (95% CI 0.18 to 0.24), coefficient of variation 9.2%).
The HR percentiles allow for a scientifically based use of HR when assessing newborn infants born at term.
心率（HR）是新生儿的一个重要临床参数，但正常范围尚未明确。我们的目的是建立健康足月新生儿出生后 24 小时内通过听诊获得的 HR 的正常参考范围和个体变化。
观察性研究。
挪威的一家医院。
在出生后 2、4、8、16 和 24 小时，通过听诊评估 30 秒的 HR。听诊通过与心电图记录进行验证。
在安静休息状态下入睡或清醒的健康足月新生儿。
静息心率百分位曲线的构建。
该研究纳入了 953 名婴儿。2 小时龄时 50 百分位心率为 126 次/分（bpm），此后为 120-122 bpm。相应的第 2 和 98 百分位心率为 102（此后为 96-100）bpm 和 162（此后为 150-156）bpm。清醒时心率比入睡时高 5.6 bpm，趴在妈妈胸前时比在婴儿床里时高 4.9 bpm，女孩比男孩高 1.6 bpm，直肠温度每升高 0.1°C，心率增加 0.5 bpm。分娩方式、胎粪污染、出生体重和母亲孕期吸烟对心率没有影响。对于每个婴儿，在出生后的 24 小时内，心率变化很大（组内相关系数 0.21（95%CI 0.18 至 0.24），变异系数 9.2%）。
心率百分位可用于评估足月新生儿的 HR，具有科学依据。
