Division of Neonatology, Department of Pediatrics and Adolescent Medicine, Medical University of Graz, Graz, Austria. Research Unit for Neonatal Micro- and Macrocirculation, Department of Pediatrics and Adolescent Medicine, Medical University of Graz, Graz, Austria.
Physiol Meas. 2020 Aug 11;41(7):075003. doi: 10.1088/1361-6579/ab998b.
Near-infrared spectroscopy (NIRS) combined with venous occlusions enables peripheral-muscle oxygenation and perfusion monitoring.
The aim of the present exploratory observational study was to evaluate peripheral-muscle oxygenation and perfusion during the first 24 h after birth in stable preterm neonates.
Secondary outcome parameters of prospective observational studies were analysed. Preterm neonates with peripheral-muscle NIRS measurements combined with venous occlusion on the first day after birth were included. Neonates without circulatory support and without signs of infection/inflammation were included. Neonates were stratified in four groups according to their measurement time-point (6 h-periods) and matched 2:1 for gestational age ±1 week. For each group haemoglobin flow (Hbflow), oxygen-delivery (DO2), oxygen-consumption (VO2), fractional-oxygen-extraction (FOE), tissue-oxygenation-index (TOI) and mixed-venous-oxygenation (SvO2) were calculated. Neonates with measurements during the first 6-hour time period were compared to neonates with measurements of the following time periods.
40 preterm neonates (gestational age (median(IQR)): 33.5(32.5-34.1)weeks) measured during the first 6 h period after birth were compared to 20 preterm neonates measured in each of the following 6 h periods (period two: 33.7(33.1-34.3)weeks; period three: 34.1(33.2-34.6)weeks; period four: 33.8(32.6-34.6)weeks). Hbflow, DO2 and SvO2 were significantly higher in the second and third 6 h time period compared to the first 6 h period. VO2 did not change significantly during the first day after birth. FOE was significantly lower in the second, third and fourth time period compared to the first 6 h period. TOI showed a non-significant trend towards higher values in the third period compared to the first 6 h period.
In preterm neonates Hbflow, DO2, SvO2 increased, FOE decreased and TOI showed a trend towards increase during the first day after birth, whereas VO2 did not change. Changes of peripheral-muscle oxygenation during the first day after birth in stable preterm neonates are different to already published changes thereafter.
近红外光谱（NIRS）与静脉闭塞相结合，可实现外周肌肉的氧合和灌注监测。
本探索性观察研究的目的是评估稳定的早产儿出生后 24 小时内的外周肌肉氧合和灌注情况。
对前瞻性观察研究的次要结局参数进行分析。纳入出生后第一天接受外周肌肉 NIRS 测量并结合静脉闭塞的早产儿。纳入无循环支持且无感染/炎症迹象的早产儿。根据他们的测量时间点（6 小时时间段）将早产儿分为四组，并按胎龄±1 周进行 2:1 配对。为每组计算血红蛋白流量（Hbflow）、氧输送（DO2）、氧消耗（VO2）、氧摄取分数（FOE）、组织氧合指数（TOI）和混合静脉氧饱和度（SvO2）。将第一个 6 小时时间段内进行测量的早产儿与随后的时间点进行测量的早产儿进行比较。
比较了 40 名早产儿（胎龄（中位数（IQR））：33.5（32.5-34.1）周）在出生后前 6 小时内进行的测量，与在随后的每个 6 小时时间段内进行的 20 名早产儿进行比较（第 2 时间段：33.7（33.1-34.3）周；第 3 时间段：34.1（33.2-34.6）周；第 4 时间段：33.8（32.6-34.6）周）。与前 6 小时时间段相比，第 2 和第 3 个 6 小时时间段的 Hbflow、DO2 和 SvO2 明显升高。出生后第一天，VO2 无明显变化。与前 6 小时时间段相比，第 2、第 3 和第 4 时间段的 FOE 明显降低。与前 6 小时时间段相比，第 3 个时间段的 TOI 值呈升高趋势，但无统计学意义。
在早产儿中，出生后第一天，Hbflow、DO2、SvO2 增加，FOE 降低，TOI 呈上升趋势，而 VO2 没有变化。与出生后已发表的变化不同，稳定的早产儿出生后第一天外周肌肉氧合的变化不同。
