Mayer Benjamin, Pohl Moritz, Hummler Helmut D, Schmid Manuel B
Institute of Epidemiology and Medical Biometry, Ulm University, Germany.
Department of Pediatrics and Adolescent Medicine, Division of Neonatology and Pediatric Intensive Care, Ulm University Medical Centre, Germany.
J Neonatal Perinatal Med. 2017;10(3):267-273. doi: 10.3233/NPM-16124.
Hypoxemic episodes commonly occur in very preterm infants and may be associated with several adverse effects. Cerebral tissue oxygen saturation (StO2) as measured by near infrared spectroscopy (NIRS) may be a useful measure to assess brain oxygenation. However, knowledge on variability of StO2 is limited in preterm infants at this time, so StO2 dependency on arterial oxygenation (SpO2) and heart rate (HR) was assessed in preterm infants using statistical methods of time series analysis.
StO2, SpO2, and HR were recorded from 15 preterm infants every 2 seconds for six hours. Statistical methods of time series and longitudinal data analysis were applied to the data.
The mean StO2 level was found as 72% (95% confidence interval (CI) 55.5% -85.5%) based on a moving average process with a 5 minute order. Accordingly, longitudinal SpO2 measurements showed a mean level of 91% (95% CI 69% -98%). Generally, compensation strategies to cope with both StO2 and SpO2 desaturations were observed in the studied patients. SpO2 had a significant effect on cerebral oxygenation (p < 0.001), but HR did not, which led to inconclusive results considering different time intervals.
In infants with intermittent hypoxemia and bradycardia, we found a mean StO2 level of 72% and a strong correlation with SpO2. We observed large differences between individuals in the ability to maintain StO2 at a stable level.
低氧血症发作常见于极早产儿，可能与多种不良反应相关。通过近红外光谱（NIRS）测量的脑组织氧饱和度（StO2）可能是评估脑氧合的有用指标。然而，目前关于早产儿StO2变异性的知识有限，因此使用时间序列分析的统计方法评估了早产儿StO2对动脉氧合（SpO2）和心率（HR）的依赖性。
每2秒记录15名早产儿的StO2、SpO2和HR，持续6小时。对数据应用时间序列和纵向数据分析的统计方法。
基于5分钟阶数的移动平均过程，发现平均StO2水平为72%（95%置信区间（CI）55.5%-85.5%）。相应地，纵向SpO2测量显示平均水平为91%（95%CI 69%-98%）。一般来说，在研究患者中观察到了应对StO2和SpO2饱和度下降的补偿策略。SpO2对脑氧合有显著影响（p<0.001），但HR没有，考虑到不同的时间间隔，这导致结果不确定。
在伴有间歇性低氧血症和心动过缓的婴儿中，我们发现平均StO2水平为72%，且与SpO2有很强的相关性。我们观察到个体在将StO2维持在稳定水平的能力上存在很大差异。
