Badalian S S, Fox H E, Baxi L V, Chao C R
Department of Obstetrics and Gynecology, College of Physicians and Surgeons, Columbia University, New York, New York, USA.
J Matern Fetal Med. 1996 Jul-Aug;5(4):206-10. doi: 10.1002/(SICI)1520-6661(199607/08)5:4<206::AID-MFM8>3.0.CO;2-O.
The purpose of our study was to determine the Doppler ultrasound characteristics of fetal breathing-related nasal fluid flow velocity in pregnancies complicated by diabetes mellitus and to examine any changes in the timing parameters of fetal breath cycle relative to maternal blood glucose level. Fetal nasal fluid flow velocity was studied in 67 women at 30-41 weeks of gestation. In 37 cases, the pregnancy was uncomplicated; in 13 cases, the pregnancy was complicated by type I diabetes mellitus; and in 17 cases, the pregnancy was complicated by gestational diabetes. At the examination, subjects with diabetes mellitus were grouped by glucose control (normoglycemic and hyperglycemic) and by gestational age: 30-36 weeks and 37-41 weeks. Maternal hyperglycemia was defined as a plasma glucose value ranging from 140 to 205 mg per 100 ml. A continuous videotape record of the spectral Doppler imaging of fluid flow velocity in the nose was made during each study session. Based on a sample of 25 consecutive fetal breaths, the timing components of breath cycles were determined: time of inspiration (Ti), time of expiration (Te), breath-to-breath interval (Ttotal), and ratio of Ti and Te (Ti/Te). There was a statistically significant difference between the Ttotal (msec) at 30-36 weeks' gestation in the cases of diabetes mellitus with maternal normoglycemia (1,050 +/- 68 SEM) and uncomplicated pregnancy with maternal normal carbohydrate intolerance (1,221 +/- 52). There was a similar difference in the values of Te (552 +/- 37 and 660 +/- 29, respectively) at 30-36 weeks. In cases of maternal hyperglycemia at 30-36 weeks' gestation, the value of Te (689 +/- 84) was significantly higher than in cases of normoglycemia (552 +/- 37). At 37-41 weeks' gestation, only the fetal Ti/Te ratio in normoglycemic diabetic patients was significantly lower than in an uncomplicated pregnancy. No differences were found in the other timing parameters at this gestational age group in cases of diabetes mellitus relative to maternal blood glucose level. No relationship was found between the value of maternal blood glucose and either fetal Ttotal (r2 = 0.003), or Ti/Te ratio (r2 = 0.0001) in cases of diabetes mellitus. Expiratory phase of fetal breath cycle even in well-controlled normoglycemic diabetic women, is significantly shorter than in uncomplicated pregnancies before 37 weeks of gestation. Maternal hyperglycemia in these cases prolonged the duration of expiratory phase of fetal breath cycle and significantly decreased the Ti/Te ratio more than 15% at 30-36 weeks of gestation. It is suggested that blood glucose level is involved in the regulation of fetal respiratory center in pregnancies complicated by diabetes mellitus.
我们研究的目的是确定妊娠合并糖尿病时胎儿呼吸相关鼻内液体流速的多普勒超声特征，并研究胎儿呼吸周期的时间参数相对于母体血糖水平的任何变化。在67名妊娠30 - 41周的女性中研究了胎儿鼻内液体流速。其中37例妊娠无并发症；13例妊娠合并I型糖尿病；17例妊娠合并妊娠期糖尿病。检查时，糖尿病患者按血糖控制情况（血糖正常和高血糖）和孕周分组：30 - 36周和37 - 41周。母体高血糖定义为血浆葡萄糖值在每100毫升140至205毫克之间。每次研究期间都对鼻内液体流速的频谱多普勒成像进行连续录像记录。基于连续25次胎儿呼吸的样本，确定呼吸周期的时间成分：吸气时间（Ti）、呼气时间（Te）、呼吸间隔时间（Ttotal）以及Ti与Te的比值（Ti/Te）。妊娠30 - 36周时，母体血糖正常的糖尿病患者的Ttotal（毫秒）（1,050±68标准误）与母体碳水化合物耐量正常的无并发症妊娠患者（1,221±52）之间存在统计学显著差异。30 - 36周时Te值（分别为552±37和660±29）也有类似差异。妊娠30 - 36周母体高血糖时，Te值（689±84）显著高于血糖正常时（552±37）。妊娠37 - 41周时，仅血糖正常的糖尿病患者的胎儿Ti/Te比值显著低于无并发症妊娠。在该孕周组，糖尿病患者相对于母体血糖水平，其他时间参数未发现差异。在糖尿病患者中，母体血糖值与胎儿Ttotal（r2 = 0.003）或Ti/Te比值（r2 = 0.0001）之间均未发现相关性。即使是血糖控制良好的血糖正常的糖尿病女性，其胎儿呼吸周期的呼气期在妊娠37周前也明显短于无并发症妊娠。这些情况下的母体高血糖延长了胎儿呼吸周期呼气期的持续时间，并在妊娠30 - 36周时使Ti/Te比值显著降低超过15%。提示血糖水平参与了妊娠合并糖尿病时胎儿呼吸中枢的调节。
