Vesalainen R K, Ekholm E M, Jartti T T, Tahvanainen K U, Kaila T J, Erkkola R U
Department of Medicine, Turku University Central Hospital, Finland.
Br J Obstet Gynaecol. 1999 Mar;106(3):238-43. doi: 10.1111/j.1471-0528.1999.tb08237.x.
To study the acute effects of tocolytic treatment with intravenous ritodrine on cardiovascular autonomic regulation.
Validated methods to assess cardiovascular autonomic nervous function-heart rate and blood pressure variability and vagal cardiac baroreflex sensitivity-were measured before and during ritodrine infusion.
Turku University Central Hospital, Turku, Finland.
Twelve pregnant women admitted to hospital for threatened preterm labour.
Electrocardiogram and continuous noninvasive finger blood pressure signals were recorded in each woman, resting in a supine position. Autoregressive spectrum analysis was used to quantify short term heart rate and blood pressure variability. Vagal cardiac baroreflex sensitivity was measured as the bradycardia response to an intravenous bolus injection of phenylephrine.
Vagal cardiac baroreflex sensitivity and spectrum analysis indices of short term heart rate and blood pressure variability.
Ritodrine significantly decreased vagal cardiac baroreflex sensitivity as well as total (0.00-0.40 Hz), low frequency (0.04-0.15 Hz) and high frequency (0.15-0.40 Hz) power bands of the heart rate variability spectrum. Ritodrine significantly increased mean heart rate and the low frequency power band of the systolic blood pressure variability spectrum.
In pregnant women with threatened preterm labour intravenous administration of ritodrine decreases vagal cardiac baroreflex sensitivity and vagal modulation of heart rate, and increases sympathetically mediated blood pressure variability. Decreased baroreflex sensitivity and heart rate variability are known to be associated with a poor prognosis in some patient groups, so the effects of ritodrine tocolysis may be unfavourable in women with impaired circulatory homeostasis.
研究静脉注射利托君进行保胎治疗对心血管自主调节的急性影响。
在输注利托君之前及期间，采用经过验证的方法评估心血管自主神经功能——心率和血压变异性以及迷走神经心脏压力反射敏感性。
芬兰图尔库图尔库大学中心医院。
12名因先兆早产入院的孕妇。
让每位孕妇仰卧休息，记录心电图和连续无创手指血压信号。采用自回归谱分析来量化短期心率和血压变异性。通过静脉推注去氧肾上腺素时的心动过缓反应来测量迷走神经心脏压力反射敏感性。
迷走神经心脏压力反射敏感性以及短期心率和血压变异性的谱分析指标。
利托君显著降低了迷走神经心脏压力反射敏感性以及心率变异性谱的总功率（0.00 - 0.40赫兹）、低频功率（0.04 - 0.15赫兹）和高频功率（0.15 - 0.40赫兹）。利托君显著提高了平均心率以及收缩压变异性谱的低频功率带。
对于先兆早产的孕妇，静脉注射利托君会降低迷走神经心脏压力反射敏感性和心率的迷走神经调节，并增加交感神经介导的血压变异性。已知压力反射敏感性降低和心率变异性降低在某些患者群体中与预后不良相关，因此利托君保胎治疗的效果可能对循环稳态受损的女性不利。
