Andriessen Peter, Janssen Ben J A, Berendsen Ralph C M, Oetomo S Bambang, Wijn Pieter F F, Blanco Carlos E
Máxima Medical Center, Neonatal Intensive Care Unit, Veldhoven, P.O. Box 7777, 5500 MB, The Netherlands.
Pediatr Res. 2004 Dec;56(6):939-46. doi: 10.1203/01.PDR.0000145257.75072.BB. Epub 2004 Oct 6.
To study cardiovascular autonomic control, we assessed the effect of atropine on heart rate (HR) and blood pressure (BP) variability in 12 preterm infants (range 26-32 wk) before intubation for respiratory insufficiency. Spectral power analysis of R-R interval and systolic BP (SBP) series were estimated in a low-frequency (LF; 0.04-0.15 Hz) and high-frequency (HF; 0.4-1.5 Hz) band and evaluated for a 10-min period before and a 10-min period after atropine sulfate (0.01 mg/kg). Baroreceptor reflex (BR) functioning was estimated using transfer function analysis at LF (coherence, gain, and phase). Atropine resulted in a significant 12% increase in steady-state HR (p < 0.01) and unchanged SBP. For R-R interval series, the total spectral power decreased 6-fold (p < 0.01), which was predominantly due to a reduction in the LF band (16-fold; p < 0.01). In contrast, we observed a significant increase (25%; p < 0.05) in total spectral power of SBP series partly as a result of an increase in HF power. The LF power of SBP series was not altered. The median LF transfer gain (BR sensitivity) between SBP and R-R interval decreased from 4.2 to 1.4 ms/mm Hg (p < 0.01) after atropine. The LF phase relationship (BP leads R-R interval fluctuations by approximately 4 s) was not changed after atropine. In conclusion, even in preterm infants in distress, atropine modulates HR and BP variability, suggesting that BR-mediated parasympathetic control of heart rate is of significance for cardiovascular control at that age.
为研究心血管自主神经控制，我们评估了阿托品对12例呼吸功能不全需插管的早产儿（孕周26 - 32周）心率（HR）和血压（BP）变异性的影响。在注射硫酸阿托品（0.01 mg/kg）前10分钟和后10分钟期间，对R - R间期和收缩压（SBP）序列进行频谱功率分析，估计低频（LF；0.04 - 0.15 Hz）和高频（HF；0.4 - 1.5 Hz）频段的频谱功率，并进行评估。使用低频段的传递函数分析（相干性、增益和相位）估计压力感受器反射（BR）功能。阿托品使稳态心率显著增加12%（p < 0.01），而收缩压未改变。对于R - R间期序列，总频谱功率下降了6倍（p < 0.01），这主要是由于低频段功率下降（16倍；p < 0.01）。相反，我们观察到SBP序列的总频谱功率显著增加（25%；p < 0.05），部分原因是高频功率增加。SBP序列的低频功率未改变。阿托品注射后，SBP与R - R间期之间的中位数低频传递增益（BR敏感性）从4.2降至1.4 ms/mm Hg（p < 0.01）。阿托品注射后，低频相位关系（血压领先R - R间期波动约4秒）未改变。总之，即使在窘迫的早产儿中，阿托品也能调节心率和血压变异性，这表明压力感受器反射介导的心率副交感神经控制在该年龄段对心血管控制具有重要意义。
