产程中持续内监护下行羊膜腔输液及羊水置换治疗胎儿窘迫

目的 探讨产程中持续内监护下行羊膜腔输及羊水置换,对治疗胎儿窘迫的意义。方法 对产程中出现频发可变减速合并羊水胎粪污染者１３６例,随机分为观察组与对照组各６８例,观察组在持续内监护下行羊膜腔输液或羊水置换。对照组给予吸氧、改变体位、静脉输液等治疗。结果观察组经羊膜腔输液５００￣１０００ｍｌ,ＶＤ波消失或明显改善者占９１．２％,同时对观察组中４８例羊水Ⅱ度以上粪染者行羊水置换,其中３９例羊水国 清亮     

第一产程异常胎心监护图形与新生儿结局的关系

目的　探讨第一产程异常胎心监护图形与新生儿结局的关系。方法　回顾分析 2 0 0 2年 8月至 2 0 0 3年 6月在我院足月单胎头位分娩产妇 ,第一产程中胎心率 (FHR)异常图形 2 1 7例 (观察组 )和FHR正常图形的2 6 9例 (对照组 )的临床资料。结果　第一产程异常FHR图形的发生率为 4 4 7% ,常见类型为轻度变异减速(6 4 5 % )、基线变异减弱 (2 1 6 % )和轻度心动过速 (1 2 0 % )。晚期减速、基线变异减弱和重度变异减速是导致新生儿窒息的危险因素。观察组羊水过少 (5 1 % )、脐带缠绕 (2 2 6 % )、羊水粪染 (1 0 6 % )、新生儿窒息 (6 5 % )、新生儿转入NICU(1 0 1 % )的发生率和剖宫产率 (31 8% )明显高于对照组 (P <0 0 5 )。结论　第一产程异常FHR图形的发生率较高 ,其中晚期减速、基线变异减弱、重度变异减速与新生儿窒息的发生相关 ,其他图形可在严密监护下继续试产     

The role of antepartum testing in the management of postterm pregnancies with heavy meconium in early labor

The documented association between heavy meconium in early labor and increased perinatal morbidity and mortality has alerted physicians to the presence of a potential high-risk fetal condition and to the possible need for immediate fetal blood pH determination. The purpose of this study was to determine whether antepartum fetal assessment can predict whether a postterm fetus with heavy meconium in early labor is at low or high risk for an adverse perinatal outcome. Eight hundred thirty-nine postterm patients were followed with antepartum testing, consisting of twice-weekly fetal heart rate (FHR) testing and ultrasonic amniotic fluid volume estimation. Overall, patients with heavy meconium in early labor had a significantly greater frequency of fetal distress. However, when women with heavy meconium in early labor were separated according to their antepartum testing results, those with normal results were found to have no greater risk for fetal distress or perinatal morbidity than women with normal testing and subsequently clear amniotic fluid. These findings suggest that postterm patients with heavy meconium in early labor and normal antepartum testing can be managed in labor in the same manner as low-risk patients without meconium.     

Apgar score, meconium and acidaemia at birth in small-for-gestational age infants born at term, and their relation to neonatal neurological morbidity

Summary. Neonatal neurological morbidity was studied in relation to Apgar score, meconium stained amniotic fluid and acidaemia at birth in 247 small-for-gestational age (SGA) maturely born infants. SGA infants, and especially the severely SGA infants and those born abdominally, showed higher rates of neurological morbidity, acidaemia and meconium stained amniotic fluid than appropriate-for-gestational age (AGA) controls. The examined indicators of asphyxia at birth showed slightly higher correlation coefficients with the 'neonatal neurological optimality score'(NNOS) in SGA, than in AGA term infants, but the percentage of explained variance was low, except in the 23 infants born abdominally. In this group poor neurological outcome was restricted to the 14 infants who showed signs of fetal hypoxaemia diagnosed by decelerative fetal heart rate (FHR) patterns. In 11 of them, FHR decelerations occurred antepartum. These FHR abnormalities appear to be better predictors for the neonatal neurological outcome than indicators of asphyxia at birth.     

Apgar score, meconium and acidaemia at birth in small-for-gestational age infants born at term, and their relation to neonatal neurological morbidity

Neonatal neurological morbidity was studied in relation to Apgar score, meconium stained amniotic fluid and acidaemia at birth in 247 small-for-gestational age (SGA) maturely born infants. SGA infants, and especially the severely SGA infants and those born abdominally, showed higher rates of neurological morbidity, acidaemia and meconium stained amniotic fluid than appropriate-for-gestational age (AGA) controls. The examined indicators of asphyxia at birth showed slightly higher correlation coefficients with the 'neonatal neurological optimality score' (NNOS) in SGA, than in AGA term infants, but the percentage of explained variance was low, except in the 23 infants born abdominally. In this group poor neurological outcome was restricted to the 14 infants who showed signs of fetal hypoxaemia diagnosed by decelerative fetal heart rate (FHR) patterns. In 11 of them, FHR decelerations occurred antepartum. These FHR abnormalities appear to be better predictors for the neonatal neurological outcome than indicators of asphyxia at birth.     

Misoprostol for cervical ripening and labor induction in pregnancies with oligohydramnios

The efficacy and safety of misoprostol for cervical ripening and labor induction in patients with oligohydramnios was investigated. 57 pregnancies with oligohydramnios and 58 cases with a normal amniotic fluid volume (controls) were enrolled in this prospective trial. All patients received 50 microg of intravaginal misoprostol every 5 h. Primary outcomes were: cesarean section rate; induction to delivery time; oxytocin augmentation; uterine hyperstimulation; meconium passage; fetal heart rate (FHR) changes; fetal distress requiring delivery, and Apgar scores. There were no differences in the mean time to delivery, cesarean section rate, oxytocin augmentation or Apgar scores. The mean induction to delivery time in oligohydramnios and control groups were, 11 h 43 min and 11 h 18 min, respectively (p > 0.05). FHR changes were observed in 26.3% of oligohydramnios group and 32.7% of control group (p > 0.05). There was no statistically significant difference in the cesarean section rate and the uterine hyperstimulation between the 2 groups. These data suggest that misoprostol can be used as an effective agent for cervical ripening and labor induction in pregnancies with oligohydramnios without increasing the risk for perinatal outcome, compared to those with normal amniotic fluid volumes.     

Value of a screening fetal heart rate tracing in the latent phase of labor

We studied the value of a screening fetal heart rate (FHR) tracing obtained on 405 women in the latent phase of labor on presentation to the labor-and-delivery suite. All pregnancies were at term and had a cephalic presentation. Thirty-two women in the sample studied underwent a cesarean section for fetal distress. Using that end point, a screening FHR tracing in the admitting room had a sensitivity of 57%, specificity of 98%, positive predictive value of 75% and overall efficiency of 95%. One- and five-minute Apgar scores and thick meconium staining of the amniotic fluid were also examined. While no statistically significant differences were found (P less than .2 for Apgar score and less than .06 for meconium), there was a trend that might have been significant if more women had been studied. A screening FHR tracing on all women at term in the latent phase of labor will identify the majority of those who will develop fetal distress in labor. Women with an abnormal screening tracing should be admitted to the hospital and the fetal status evaluated further.     

The relationship between fetal heart rate accelerations, fetal movements, and uterine contractions

The association between fetal heart rate (FHR) accelerations and fetal movements during uterine contractions was studied in 52 pregnant women near term or at the beginning of labor. FHR and uterine contractions were recorded by tococardiograph. At the same time, fetal movements, whether associated or not with contractions, were viewed by real-time ultrasound. During uterine contractions, 95.5% of the FHR accelerations were associated with fetal movements. Also, 90.9% of the accelerations which appeared when the uterus was not contracting were associated with fetal movements. Fetal movements were not seen in 91% of uterine contractions which were not associated with FHR accelerations. The suggestion is made that uterine contractions stimulate both fetal movements and FHR accelerations.     

Fetal tachycardia and meconium staining: A sign of fetal infection

A retrospective study was carried out on 72 liveborn babies in whom perinatal infection was suspected. Twenty-nine of the 72 neonates were effectively infected. Analysis of intrapartum FHR recordings showed that tachycardia (base line FHR above 160 beats/min) during labor, occurred more often among infected babies (P < 0.001). When fetal tachycardia is associated with meconium stained amniotic fluid (MSAF), the relative risk of fetal infection is 51 times as great as in babies without MSAF. Fetal tachycardia is not related to maternal fever nor to prematurity. It is not a sign of limited placental or amniotic fluid infection, but implies infection of the fetus itself. Since most infected babies displayed infectious diarrhea immediately at birth, it is suggested that MSAF may eventually be due to antenatal intestinal infection and intrauterine emission of infected stools. Although great caution is advocated for the management of labor in the presence of fetal tachycardia, MSAF should not be always regarded as a sign of acute fetal distress when antenatal infection of the fetus is suspected.     

Significance of meconium staining of the amniotic fluid

The study was conducted to determine the significance of meconium staining and more specifically its association with fetal heart rate patterns. Five hundred and one patients in labor were examined, 106 of whom had meconium stained amniotic fluid. A multivariate analysis of the data was performed by logistic regression analysis using meconium staining as the dependent variable. The determinants of meconium in the amniotic fluid were gestational age, base deficit, calcified placenta, late decelerations and placental weight. The following variables had no effect on the occurrence of meconium: maternal age, type of risk, parity, fetal sex, duration of labor, duration of the second stage of labor, entanglement of the umbilical cord, FHR variability, variable decelerations, oxytocin usage, type of anesthesia, maternal smoking and alcohol consumption habits. In conclusion, meconium in the amniotic fluid seems to be associated with placental rather than with umbilical insufficiency.     

羊膜腔输液治疗在产时应用的临床分析

目的 :分析羊膜腔输液 (amnioinfusion,AI)治疗产时羊水过少、胎膜早破和胎粪性羊水的临床意义。方法 :选择产程中发生胎心异常合并羊水过少、胎膜早破和羊水胎粪污染的孕产妇 1 0 1例 ,随机分为治疗组 51例 ,对照组 50例。治疗组在胎心监护下行羊膜腔输液或羊水置换 ;对照组给予吸氧 ,改变体位 ,静滴 5% Na HCO3等治疗。结果 :治疗组经羊膜腔输液 50 0～ 1 0 0 0 ml,胎心可变减速 (variable deceleration,VD)和长时减速 (period long deceleration,PL D)消失或明显改善 44例 ,有效率占 86 .3% ,明显高于对照组 (2 2 % ) ,两组比较差异有显著性 (P<0 .0 1 )。治疗组 1 9例胎粪性羊水行羊水置换 ,有 1 7例羊水转为清亮或 度混浊。治疗组产程时间比对照组缩短 ,治疗组和对照组剖宫产率分别为 1 3.7%和 34.0 % ,新生儿窒息率分别为 3.9%和 42 .0 % ;对照组胎粪吸入性肺炎 9例 ,新生儿死亡 3例 ,治疗组仅一例发生胎粪吸入性肺炎 ,无新生儿死亡。产褥病率两组比较 ,差异无显著性 (P>0 .0 5)。结论 :羊膜腔输液是治疗产时羊水过少、胎膜早破、胎粪性羊水的有效方法     

The Value of Amnioscopy in Surveillance of Postdate Pregnancy

The accuracy and reliability of amnioscopy in detecting the presence of meconium in amniotic fluid and in predicting fetal distress were evaluated in 289 postdate pregnancies. Meconium-stained amniotic fluid tended to be associated with complications of pregnancy such as ABO incompatibility (p less than 0.05), the need for operative delivery (p less than 0.02), and fetal distress at birth (p less than 0.05). Amnioscopy failed to detect the presence of meconium antenatally in most cases (57%), and positive amnioscopy for meconium was unrelated to the incidence of fetal distress. When meconium was present, induction of labour was ineffective in reducing the incidence of fetal distress. Amnioscopy is not recommended for the monitoring of postdate pregnancies.     

产程中应用度冷丁对胎心率及宫缩的影响

目的探讨度冷丁对胎心率及宫缩的影响。方法对潜伏期精神紧张或休息、进食不佳的３０例产妇肌内注射度冷丁１００ｍｇ,用胎儿内监护仪监测胎心率及宫腔压力,观察用药后３０分钟、１小时、２小时的胎心率变化及宫缩情况。结果用药３０分钟后胎心率基线有所下降,１～２小时下降明显但仍在正常范围。用药３０分钟后宫腔静止压力下降。用药１小时后,不协调宫缩得以改善,同时,度冷丁对宫缩频率及强度有加强作用。结论潜伏期使用度冷丁能改善产妇一般情况,虽胎心率有所下降但不造成胎儿窘迫;并有增强宫缩频率与强度和调整不协调宫缩的作用     

Intracranial pressure and fetal heart rate in a hydrocephalic fetus during labor.

Intra-uterine pressure (IUP), intracranial pressure (ICP) and fetal heart rate (FHR) were simultaneously recorded during labor in a severely hydrocephalic fetus. After cephalocentesis, 600 ml of liquor cerebrospinalis was drained. ICP exceeded IUP, but the increase in ICP was less than the increase in IUP during most of the contractions. The FHR showed marked decelerations during uterine contractions and changed gradually into a persistent bradycardia. The pathophysiology of fetal heart rate patterns during labor is discussed and the literature has been reviewed.     

The relationship of heart rate patterns and tissue pH in the human fetus.

The relationship between different FHR patterns and fetal tissue pH in 68 high-risk gravidas in labor was analyzed. A tissue pH electrode was placed in the fetal scalp and tissue pH recorded on a fetal monitor every 15 seconds along with uterine contractions and continuous fetal heart rate. The tissue pH changes correlated with the FHR patterns in a manner consistent with current concepts of fetal stress. Trend monitoring of fetal tissue pH in labor may prove useful in the management of high-risk patients in labor.     

Subclassification of small-for-gestational-age fetus using fetal Doppler velocimetry

Our purpose was to determine whether small-for-gestational-age (SGA) fetus can be divided to subclassified groups using fetal Doppler velocimetry. Fifty-four pregnant women with SGA infant delivered after 37 weeks of gestation were studied. After 24 weeks of gestation, fetal middle cerebral artery puslatility index (MCAPI) and umbilical artery pulsatility index (UAPI) were measured at 2- to 3-week intervals using Doppler ultrasound. Perinatal outcomes [operative delivery due to fetal distress, abnormal fetal heart rate (FHR) pattern, meconium staining, low Apgar score (<7), neonatal acidosis (umbilical artery blood pH <7.15), neonatal intensive care unit (NICU) admission due to neonatal asphyxia, and decreased amniotic fluid] were compared in subclassified SGA groups using fetal Doppler velocimetry. The number of SGA fetuses with normal MCAPI and UAPI (normal SGA group) was 39, and those with significantly low MCAPI but normal UAPI (eventful SGA group) 15, respectively. Birth age and birth weights in the eventful SGA group were significantly earlier and lower than those in the normal SGA group, respectively (p < 0.05, and p < 0.005). There were significant increases in operative deliveries, abnormal FHR patterns and decreased amniotic fluid in eventful SGA group, when compared with events related to normal SGA group. However, there were no significant differences in meconium staining of amniotic fluid, low Apgar score, neonatal acidosis, and NICU admission between the two groups. These results suggest that SGA fetus with abnormally low MCAPI but normal UAPI has more poor perinatal outcomes, compared with that with normal MCAPI and UAPI.     

Umbilical artery Doppler velocimetry as a labor admission test

Doppler ultrasound of the umbilical artery flow velocity waveform was studied prospectively as an admission test at the labor ward. Recordings were made in 575 women in various stages of labor before, during, and after uterine contractions, and evaluated in relation to intrapartum and fetal outcome variables. No association was found between abnormal flow velocity waveforms and cord complications, meconium-stained amniotic fluid, or abnormal fetal heart rate tracing, nor was there any association with operative delivery for fetal distress or low Apgar scores at 1 and 5 minutes. Small for gestational age fetuses had significantly more abnormal flow velocity waveforms than appropriate for gestational age fetuses, and so had those with umbilical artery acidemia compared with those with normal pH. The results indicate that Doppler recording of the umbilical artery flow velocity waveform as an admission test at the labor ward is not a good predictor of fetal distress in an unselected population.     

Fetal heart rate during labour: definitions and interpretation

Continuous fetal heart rate monitoring is widely used during labor even in low risk pregnancies. Consensus is necessary to define and interpret accurately the different FHR patterns. The normal FHR tracing include baseline rate between 110-160 beats per minute (bpm), moderate variability (6-25 bpm), presence of accelerations and no decelerations. Uterine activity is monitored simultaneously: contractions frequency, duration, amplitude and relaxation time must be also normal. Abnormal baseline heart rate during 10 minutes or more is termed tachycardia above 160 bpm (except for FIGO above 150) and bradycardia below 110 bpm. Variability is minimal below 6 bpm and absent when non visible. Decelerations are classified as early, variable, late, and prolonged. Early and late decelerations have an onset gradual decrease of FHR, in contrast variable decelerations have an abrupt onset. Early deceleration is coincident in timing with uterine contraction. Variable deceleration is variable in onset, duration and timing, and may be described as typical or non reassuring. Late deceleration is associated with uterine contraction; the onset, nadir, and recovery occur after onset, peak and end of the contraction. Prolonged deceleration is lasting more than two but less 10 minutes, with almost onset abrupt and no repetition. Electronic fetal monitoring is a method to detect risk of fetal asphyxia; analysis and interpretation of FHR patterns are difficult with a high false positive rate, increasing operative deliveries. The patterns who are predictive of severe fetal acidosis include recurrent late or variable or prolonged decelerations or bradycardia, with absent FHR variability, and sudden severe bradycardia. The other FHR patterns are not conclusive and defined as non reassuring; obstetrical risk factors must be considered and other method (like scalp sampling for pH) utilised to evaluate fetal state.     

Use of prostaglandin E2 for cervical ripening in pregnancies with oligohydramnios

The effectiveness of intracervical prostaglandin E2 (PGE2) was studied in 96 primigravidas with unfavorable cervix and need for induction of labor. Group A consisted of 49 oligohydramnios and group B of 47 cases with normal amniotic fluid volume (controls). A single dose of 0.5 mg PGE2 gel was applied intracervically and several parameters were recorded during the next hours. The mean number of uterine contractions increased during the first 2 h in both groups, decreased during the next one and did not change significantly afterwards. The mean fetal heart rate (FHR) in group A decreased during the first 2 h and then increased, staying always within normal limits. The mean FHR in group B increased for 2 h, decreased during the next hour and did not change significantly afterwards. No significant differences were found between the two groups regarding mode of delivery, Apgar score and neonatal acidosis. Intracervical PGE2 appeared to effectively stimulate cervical ripening and labor induction in oligohydramnios, without causing side effects to the uterus and fetus.     

Acute fetal distress

Three different clinical patterns of acute fetal distress may be observed during labor: an ante-partum hypoxia with a persistent nonreactive and "fixed" fetal heart rate (FHR) on admission to the hospital, a progressive intra-partum asphyxia manifested, as the labor continues, by a substantial rise in baseline heart rate, a loss of variability and repetitive severe variable or late decelerations, and finally, as a result of a catastrophic event, a sudden prolonged FHR deceleration to approximately 60 beats per minute lasting until delivery. However the majority of fetuses with nonreassuring tracings of FHR are neurologically intact, as evidenced by the high false-positive rate of electronic fetal monitoring (EFM). Therefore the diagnosis of fetal distress must be corroborated by complementary methods, such as continuous recording of the fetal electrocardiogram or computed-assisted EFM, fetal pulse oximetry or fetal scalp sampling with immediate determination of blood gases or lactates. Defavorable outcome of an acute fetal distress leading to neonatal encephalopathy or death is best predicted by a persisting low Apgar score (<3) for more than 5 minutes and by a severe metabolic acidosis (umbilical artery pH<7,00 and base-excess>-12mmol/l).