Latremouille Samantha, Al-Jabri Ali, Lamer Philippe, Kanbar Lara, Shalish Wissam, Kearney Robert E, Sant'Anna Guilherme M
Division of Neonatology, Department of Pediatrics, McGill University Health Center, Montreal, Canada. At the time of this study.
Division of Neonatology, Department of Pediatrics, McGill University Health Center, Montreal, Canada.
Respir Care. 2018 Jan;63(1):62-69. doi: 10.4187/respcare.05672. Epub 2017 Oct 24.
There is a paucity of studies comparing the physiological effects of nasal CPAP or non-synchronized noninvasive ventilation (ns-NIV) during the postextubation phase in preterm infants. Heart rate variability (HRV) can identify system instability before clinical or laboratory signs of deterioration. Thus, we sought to investigate any differences in HRV between those modes.
15 preterm infants with birthweight ≤1,250 g and undergoing their first extubation attempt were studied immediately after disconnection from mechanical ventilation. Electrocardiogram (ECG) recordings were obtained while on nasal CPAP and ns-NIV in a random order (30-60 min on each). Time and frequency domain analyses were used to calculate HRV from 5-min segments of ECG.
12 of 15 infants were analyzed (3 were excluded for low ECG quality): 7 successes and 5 failures. HRV parameters were higher during ns-NIV when compared to nasal CPAP, but differences were not statistically different. However, absolute and relative differences in HRV values (all time domain parameters) were significantly higher in infants who failed extubation during ns-NIV.
Nasal CPAP or ns-NIV provided immediately postextubation did not affect HRV. Interestingly, in an exploratory analysis, changes in HRV did occur during ns-NIV in the subgroup of infants who failed extubation. Hence, changes in HRV as early as 2 h after extubation should be further explored in larger studies as a potential predictor of postextubation respiratory failure.
比较鼻持续气道正压通气（CPAP）或非同步无创通气（ns-NIV）对早产儿拔管后阶段生理影响的研究较少。心率变异性（HRV）可在临床或实验室出现恶化迹象之前识别系统不稳定。因此，我们试图研究这些模式之间HRV的差异。
对15例出生体重≤1250g且首次尝试拔管的早产儿在脱离机械通气后立即进行研究。以随机顺序在鼻CPAP和ns-NIV状态下获取心电图（ECG）记录（每种状态持续30 - 60分钟）。使用时域和频域分析从ECG的5分钟片段计算HRV。
分析了15例婴儿中的12例（3例因ECG质量低被排除）：7例成功，5例失败。与鼻CPAP相比，ns-NIV期间的HRV参数更高，但差异无统计学意义。然而，ns-NIV期间拔管失败的婴儿HRV值的绝对和相对差异（所有时域参数）显著更高。
拔管后立即给予鼻CPAP或ns-NIV不影响HRV。有趣的是，在一项探索性分析中，拔管失败的婴儿亚组在ns-NIV期间确实出现了HRV变化。因此，在更大规模的研究中应进一步探索拔管后2小时内HRV的变化，作为拔管后呼吸衰竭的潜在预测指标。
