Umbilical Arterial Blood pH Research Articles

Umbilical arterial profiles as predictors of severity of hypoxic ischemic encephalopathy after perinatal asphyxia

Background: Perinatal hypoxic-ischemic encephalopathy (HIE) remains a major cause of neurodevelopmental impairment. Umbilical cord blood analysis provides an objective assessment of newborn metabolic status. Accordingly, it is recommended that physicians attempt to obtain venous and arterial samples when there is high risk of neonatal compromise.
 Objective To compare the predictive value of umbilical arterial blood pH, lactate and base deficit for subsequent development of severity of hypoxic ischemic encephalopathy (HIE) after perinatal asphyxia and comparison of these parameters to determine which one is superior in predicting severity.
 Methods Umbilical cord arterial blood of newborns with perinatal asphyxia was tested for pH, lactate, and base deficit estimation. These newborns were evaluated in level III NICU and divided into two groups. Group 1 had no or signs and symptoms of HIE I and group 2 had signs and symptoms of HIE II/III. Values of pH, lactate, and base deficit were tabulated and analyzed by receiver-operating characteristic curves. Optimal cut-off values were estimated based on the maximal Youden index.
 Results Mean pH was significantly lower in group 2 than in group 1, while lactate and base deficit were significantly higher in group 2 than in group 1. Cut-off points for determining severity of HIE were pH <7.13, lactate >6.89 mg/dL, and base deficit >7 mEq/L. Sensitivity and specificity for these cut-off points were 100% and 91.49% for pH, 100% and 85.11% for lactate, and 82.4% and 91.76% for base deficit, respectively. Predictive abilities of all three parameters were similar in determination of HIE severity.
 Conclusion Umbilical arterial pH, lactate, and base deficit have excellent accuracy to predict the severity of HIE. All three parameters have similarly good predictive ability.

Intrapartum PRSA: a new method to predict fetal acidosis?-a case-control study.

Phase-rectified signal averaging method (PRSA) represents an analysis method which applied on fetal cardiotocography (CTG) allows the quantification of the speed of fetal heart rate changes. By calculating the average deceleration capacity (ADC) an assessment of the fetal autonomic nervous system (ANS) is possible. The objective of this study was to test its ability to predict perinatal acidosis. A case-control study was performed at a University Hospital in Munich. All intrapartum CTG heart rate tracings saved during a 7-year period were considered for analysis. All neonates born with an umbilical arterial blood pH ≤ 7.10 were considered as cases. Controls were defined as healthy fetuses born with a pH ≥ 7.25. The main matching criteria were gestational age at delivery, parity, birth mode, and birth weight percentile. Exclusion criteria were a planned caesarean section, fetal malformations, and multiple pregnancies. ADC and STV were then calculated during the last 60, the last 45, and the last 30min intervals prior to delivery. Of all stored birth CTG recordings, 227 cases met the inclusion criteria and were studied. ADC was significantly higher in fetuses born with acidemia (4.85bpm ± 3.0) compared to controls (3.36bpm ± 2.2). The area under ROC curve was 0.659 (95% CI 0.608-0.710) for ADC and 0.566 (0.512-0.620) for STV (p = 0.013). This study confirms that the assessment of ADC using PRSA represents a good additional tool for the prediction of acute fetal acidosis during delivery.

Effect of epidural analgesia in trial of labor after cesarean on maternal and neonatal outcomes in China: a multicenter, prospective cohort study

BackgroundThe trial of labor after cesarean section (TOLAC) is a relatively new technique in mainland of China, and epidural analgesia is one of the risk factors for uterine rupture. This study aimed to evaluate the effect of epidural analgesia on primary labor outcome [success rate of vaginal birth after cesarean (VBAC)], parturient complications and neonatal outcomes after TOLAC in Chinese multiparas based on a strictly uniform TOLAC indication, management and epidural protocol.MethodsA total of 423 multiparas undergoing TOLAC were enrolled in this study from January 2017 to February 2018. Multiparas were divided into two groups according to whether they received epidural analgesia (study group, N = 263) or not (control group, N = 160) during labor. Maternal delivery outcomes and neonatal characteristics were recorded and evaluated using univariate analysis, multivariable logistic regression and propensity score matching (PSM).ResultsThe success rate of VBAC was remarkably higher (85.55% vs. 69.38%, p < 0.01) in study group. Epidural analgesia significantly shortened initiating lactation period and declined Visual Analogue Score (VAS). It also showed more superiority in neonatal umbilical arterial blood pH value. After matching by PSM, multivariable logistic regression revealed that the correction of confounding factors including epidural analgesia, cervical Bishop score at admission and spontaneous onset of labor were still shown as promotion probability in study group (OR = 4.480, 1.360, and 10.188, respectively; 95%CI = 2.025–10.660, 1.113–1.673, and 2.875–48.418, respectively; p < 0.001, p = 0.003, and p < 0.001, respectively).ConclusionsEpidural analgesia could reduce labor pain, and no increased risk of postpartum bleeding or uterine rupture, as well as adverse effects in newborns were observed. The labor duration of multiparas was increased, but within acceptable range. In summary, epidural analgesia may be safe for both mother and neonate in the three studied hospitals.Trial registrationChineses Clinical Trial Register, ChiCTR-ONC-17010654. Registered February 16th, 2017.

Prediction of adverse perinatal outcome by serum placental growth factor and soluble fms-like tyrosine kinase-1 in women undergoing induction of labor.

To investigate the additive value of serum placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1), measured within 24 h prior to induction of labor, to the performance of screening for adverse perinatal outcome provided by maternal risk factors and the cerebroplacental ratio (CPR). This was a prospective observational study of 795 singleton pregnancies undergoing induction of labor at ≥ 37 weeks' gestation. Before induction of labor, Doppler ultrasound was used to measure the pulsatility index (PI) in the umbilical artery (UA) and fetal middle cerebral artery (MCA) and maternal blood was obtained for measurement of serum PlGF and sFlt-1. The measured UA-PI, MCA-PI and their ratio (CPR) were converted to multiples of the median (MoM) after adjustment for gestational age, and the measured PlGF and sFlt-1 were converted to MoM after adjustment for gestational age, maternal characteristics and the machine used for the assays. Univariable and multivariable logistic regression analysis was used to determine factors that provided a significant contribution in the prediction of adverse perinatal outcome, defined as the presence of any one of Cesarean section for non-reassuring fetal status in labor, umbilical arterial or venous cord blood pH ≤ 7 and ≤ 7.1, respectively, 5-min Apgar score < 7 or admission to the neonatal intensive care unit for ≥ 24 h. The detection rate (DR) and false-positive rate (FPR) in screening for adverse perinatal outcome were determined. In pregnancies with adverse perinatal outcome, compared to those without, median serum PlGF MoM was lower (0.44; interquartile range (IQR), 0.30-0.82 vs 0.60; IQR, 0.36-1.07; P = 0.003), but median sFlt-1 MoM was not significantly different (P = 0.080). Multivariable regression analysis demonstrated that, in the prediction of adverse perinatal outcome, there was significant contribution from maternal risk factors and CPR MoM but not PlGF MoM or sFlt-1 MoM. The performance of screening for adverse perinatal outcome achieved by maternal risk factors alone (DR of 28.9% at FPR of 10%) was not improved by the addition of CPR (DR of 33.8% at FPR of 10%) (area under the curve, 0.702; 95%CI, 0.654-0.750 vs 0.712; 95%CI, 0.664-0.760; P = 0.233). Serum PlGF and sFlt-1, measured within 24 h prior to induction of labor, do not provide a significant additional contribution to maternal risk factors in the prediction of adverse perinatal outcome. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Dexmedetomidine versus sufentanil with high- or low-concentration ropivacaine for labor epidural analgesia: A randomized trial.

To study analgesic effects of dexmedetomidine or sufentanil, both combined with ropivacaine, in epidural analgesia during labor. We recruited 160 primigravidae with full-term pregnancy who received epidural anesthesia during labor and randomized them into four groups to receive epidural administration of ropivacaine combined with sufentanil (RS1 and RS2 groups) or with dexmedetomidine (RD1 and RD2 groups). Systolic blood pressure, diastolic blood pressure and heart rate before anesthesia (T1 ), 15 min after anesthesia induction (T2 ), on delivery (T3 ) and 2 h postpartum (T4 ), together with visual analogue scale scores, Bromage scores, Ramsay scores, adverse reactions during analgesia and urinary retention at 6 and 24 h postpartum were recorded; the pH, PCO2 and PO2 of umbilical cord arterial blood and Apgar scores at 1, 5 and 10 min after childbirth were assessed. RS1 group had significantly lower systolic blood pressure, diastolic blood pressure and heart rate than RD1 group at T2 and T3 (all P < 0.05), but not at T1. At T2 and T3 , the other three groups were lower than RS2 group in visual analogue scale and Ramsay scores (all P < 0.05). After childbirth, RD2 group had significantly higher PO2 result than other three groups (P < 0.05). At 6 h postpartum, RD2 group had significantly fewer cases of urinary retention than RD1 and RS1 groups (both P < 0.05). A relatively low concentration of ropivacaine, combined with dexmedetomidine, is better in analgesia during labor.

CONDISOX- continued versus discontinued oxytocin stimulation of induced labour in a double-blind randomised controlled trial

BackgroundOxytocin is an effective drug for induction of labour, but is associated with serious adverse effects of which uterine tachysystole, fetal distress and the need of immediate delivery are the most common. Discontinuation of oxytocin once the active phase of labour is established could reduce the adverse effects.The objective is to investigate how the caesarean section rate is affected when oxytocin stimulation is discontinued in the active phase of labour compared to labours where oxytocin is continued.MethodsCONDISOX is a double-blind multicentre randomised controlled trial conducted at Danish and Dutch Departments of Obstetrics and Gynaecology. The first participant was recruited on April 8 2016.Based on a clinically relevant relative reduction in caesarean section rate of 7%, an alpha of 0.05, a beta of 80%, we aim for 1200 participating women (600 in each arm).The CONDISOX trial includes women at a gestational age of 37–42 complete weeks of pregnancy, who have uterine activity stimulated with oxytocin infusion for the induction of labour. Women are randomised when the active phase of labour becomes established, to study medication containing either oxytocin (continuous group) or placebo (discontinued group) infusion. Women are stratified by birth site, indication for oxytocin stimulation (induction of labour, prelabour rupture of membranes) and parity (nulliparous, parous +/− previous caesarean section).We will compare the primary outcome, caesarean section rate, in the two groups using a chi-square test with a p-value of 0.05. If superiority is not demonstrated, we have a pre-defined post hoc non-inferiority boundary (margin, delta) at 1.09.Secondary outcomes include duration of the active phase of labour, incidence of uterine tachysystole, postpartum haemorrhage, admission to the neonatal intensive care unit, Apgar score, umbilical arterial blood pH, and birth experience.DiscussionThe high frequency of oxytocin use and the potential risks of both maternal and fetal adverse effects of oxytocin emphasise the need to determine the optimal oxytocin regime for induction of labour.Trial registrationNCT02553226 (registered September 17, 2015). Eudra-CT number: 2015–002942-30.

The impact of chorionicity and the type of twin growth on the early neonatal outcome in twin pregnancies – 20 years of experience from one tertiary perinatal center

ObjectiveTwin pregnancies are associated with higher neonatal mortality and morbidity. Growth discordance and monochorionicity are among the factors that worsen the course of pregnancy. The study aimed to assess neonatal conditions and mortality in relation to growth type and chorionicity. Materials and methodsData from 820 pregnant women with twin pregnancies and their 1640 newborns were analyzed. The Apgar score and umbilical artery blood pH, as well as the rate of complications, were compared between dichorionic diamniotic (DCDA) and monochorionic diamniotic (MCDA) twins with symmetric and discordant growth. The Student's t-test and the Pearson chi-square test were used for comparisons. ResultsThere were 576 (70.2%) DCDA pregnancies, including 421 (73.1%) with symmetric growth and 155 (26.9%) with discordant growth, and 244 (29.8%) MCDA pregnancies, including 110 (45.1%) with symmetric growth and 134 (54.9%) with discordant growth. A significantly greater percentage of twins with discordant growth occurred in women older than 34 years than in those that were younger. An Apgar score of ≤7 was significantly more common among MCDA discordant twins, while an arterial umbilical blood pH of <7.2 was more common among MCDA twins with symmetric growth. Early neonatal deaths (n = 29; 1.8%), respiratory disorders, and a birth weight of <1500 g were significantly more common in MCDA twins than in DCDA twins. ConclusionMCDA twins with growth discordance are burdened with a higher risk of neonatal morbidity and mortality than symmetric DCDA twins. Chorionicity and growth discordancy are important determinants of the outcome of twin pregnancy.

Correlation of short-term variation and Doppler parameters with adverse perinatal outcome in small-for-gestational age fetuses at term.

To evaluate the association of short-term variation (STV) and Doppler parameters with adverse perinatal outcome in small-for-gestational-age (SGA) fetuses at term. In this retrospective single-center study 97 patients with singleton SGA fetuses at term (≥ 37 + 0weeks' gestation) were examined. Inclusion criteria were a birth weight < 10th centile, cephalic presentation and planned vaginal birth. Only cases with available Doppler measurements of umbilical artery (UA) and middle cerebral artery (MCA) with calculated cerebroplacental ratio (CPR) in combination with a computerized CTG (cCTG) and STV 72h prior to delivery were eligible for analysis. Pulsatility indices (PI) were converted into multiples of median (MoM), adjusted for gestational age. The association between Doppler indices and STV values with mode of delivery [secondary cesarean delivery (CD), operative vaginal delivery (OVD), as well as secondary CD and OVD due to fetal distress] and neonatal outcome [UA blood pH ≤ 7.15 and the need of admission to the neonatal intensive care unit (NICU)] was analyzed using logistic regression analysis. There was a significant association between UA PI MoM and the rate of CD. CD due to fetal distress, OVD and OVD due to fetal distress did not show a correlation with the evaluated Doppler parameters. Furthermore, we did not find an association between low UA birth pH and Doppler parameters while neonates with the need of admission to NICU had significant higher UA PI MoM and significant lower MCA PI MoM and CPR MoM. Regarding STV, a significant effect of low STV on NICU admission was found while none of the other assessed outcome parameters were significantly associated with STV. STV and Doppler parameters in SGA fetuses at term are significantly associated to the rate of NICU admission.

On the prediction of foetal acidaemia: A spectral analysis-based approach

A computational analysis of physiological systems has been used to support the understanding of how these systems work, and in the case of foetal heart rate, many different approaches have been developed in the last decades.Our objective was to apply a new method of classification, which is based on spectral analysis, in foetal heart rate (FHR) traces to predict foetal acidosis diagnosed with umbilical arterial blood pH ≤ 7.05. Fast Fourier transform was applied to a real database for the classification approach. To evaluate the models, sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve were used.Sensitivity equal to 1, specificity equal to 0.85 and an area under the ROC curve of 0.94 were found. In addition, when the definition of metabolic acidosis of umbilical arterial blood pH ≤ 7.05 and base excess ≤ −10 mmol/L was used, the proposed methodology obtained sensitivity = 1, specificity = 0.97 and area under the ROC curve = 0.98. The proposed methodology relies exclusively on the spectral frequency decomposition of the FHR signal. After further successful validation in more datasets, this approach can be incorporated easily in clinical practice due to its simple implementation. Likewise, the incorporation of this novel technique in an intrapartum monitoring station should be straightforward, thus enabling the assistance of labour professionals in the anticipated detection of acidaemia.

Prediction of adverse perinatal outcome by cerebroplacental ratio in women undergoing induction of labor.

To investigate the performance of screening for adverse perinatal outcome by the cerebroplacental ratio (CPR) measured within 24 h prior to induction of labor. This was a prospective observational study of 1902 singleton pregnancies undergoing induction of labor at ≥ 37 weeks' gestation. Doppler ultrasound was used to measure the pulsatility index (PI) in the umbilical artery (UA) and fetal middle cerebral artery (MCA) within 24 h before induction of labor. The measured UA-PI and MCA-PI and their ratio were converted to multiples of the median after adjustment for gestational age. Univariable and multivariable logistic regression analysis was used to determine whether CPR improved the prediction of adverse perinatal outcome provided by maternal characteristics, medical history and obstetric factors. The detection rate (DR) and false-positive rate (FPR) of screening by CPR were estimated for Cesarean section for presumed fetal distress and adverse neonatal outcome, which included umbilical arterial or venous cord blood pH ≤ 7 and ≤ 7.1, respectively, 5-min Apgar score < 7, admission to the neonatal intensive care unit for > 24 h or hypoxic ischemic encephalopathy. A combination of maternal and pregnancy characteristics, including age, weight, racial origin, previous obstetric history, pre-eclampsia, gestational age at delivery and amniotic fluid volume, identified 39% of pregnancies requiring Cesarean section for fetal distress at a FPR of 10%; addition of CPR did not improve the performance of screening. In screening for adverse neonatal outcome by a combination of parity and CPR, the DR was 17% at a FPR of 10%. Low CPR, measured within 24 h prior to induction of labor, is associated with increased risk of Cesarean section for fetal distress and adverse neonatal outcome, but the performance of CPR for such surrogate measures of fetal hypoxic morbidity is poor. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Postnatal condition of the second twin in respect to mode of delivery, chorionicity and type of fetal growth.

The increased use of assisted reproductive techniques (ART) contributes to the increased rate of twin pregnancies, which are burdened with a higher risk of complications. Factors that affect the condition of the second twin are understudied. The objective of this study was to assess the impact of the delivery mode, chorionicity, amnionicity, and the type of fetal growth on the postnatal condition of the second twin. The study included data from 475 pregnant women with twin pregnancies. Maternal age, parity, chorionicity, amnionicity, type of fetal growth, mode of delivery, gestational weeks at delivery, Apgar score, and umbilical arterial blood pH were retrospectively analyzed. Data normality was checked with the Kolmogorov-Smirnov test. The paired Wilcoxon signed-rank test and χ2 test were used for comparisons between groups. To check predictive value of the analyzed variables multiple linear regression was used. The mean maternal age was 29.22 (standard deviation (SD) ±5.19) years. The maternal age and gestational age at delivery did not differ significantly between women who delivered by cesarean section (CS) and vaginal delivery (VD). In the second twin, the Apgar score and values of arterial umbilical blood pH were lower in infants delivered by VD than in those delivered by CS (6.30 ±2.83 and 7.30 ±0.12; p = 0.0209 and 7.26 ±0.12 and 7.30 ±0.11; p = 0.0236, respectively). In monochorionic diamniotic twins with asymmetric growth, the second twin achieved significantly lower outcome than the first twin. Vaginal delivery was a predictive factor for a lower Apgar score and lower values of umbilical arterial blood pH in second twins, while not in first twins. Symmetrical fetal growth of twins was a predictive factor for better postnatal condition for both twins. In twin pregnancies, VD, but not CS, is associated with increased risk of worse postnatal condition of the second twin. In monochorionic diamniotic pregnancies complicated by growth discordance, CS seems to be a reasonable mode of delivery.

Analysis of Neonatal Outcome with Supplemental Oxygen to Mother during Elective Cesarean Section under Spinal Anesthesia: A Prospective Randomized Controlled Trial.

Background:Many questions have arisen on benefits of routine use of supplemental oxygen during elective cesarean section (CS) under spinal anesthesia.Aims:The aim of this randomized controlled study was to evaluate neonatal outcome in immediate postpartum period with or without supplemental oxygen to mother, undergoing elective CS under spinal anesthesia.Materials and Methods:One hundred and thirty-four nonlaboring term pregnant women were allocated randomly into two groups to breathe room air (air group) or oxygen (oxygen group). Times from starting oxygen supplementation to delivery interval, skin incision to delivery (I-D) interval, and uterine incision to delivery (U-D) interval were recorded. APGAR scores were assessed at 1 min and 5 min after delivery. Umbilical cord blood gas analysis was done immediately to measure pH, oxygen partial pressure, carbon dioxide partial pressure (PCO2), and bicarbonate.Statistical Analysis:Statistical comparisons were performed using either Student's t-test or Mann–Whitney U-test.Results:For oxygen group versus air group, In Oxygen group, proportion of fetal acidosis was significantly less; umbilical arterial (UA) blood pH (7.22 ± 0.05 vs. 7.19 ± 0.05, P = 0.001) as well as umbilical venous (UV) blood pH (7.26 ± 0.05 vs. 7.22 ± 0.06, P < 0.001) were significantly higher and UA PCO2 (55.4 ± 9.9 vs. 62.9 ± 6.9, P = 0.001) and UV PCO2 (51.4 ± 8.2 vs. 54.3 ± 7.2, P = 0.036) were significantly lower compared to air group. APGAR scores were similar between the groups.Conclusions:Supplemental oxygen has potential benefits as demonstrated by less proportion of FA in mothers receiving supplemental oxygen.

Double-balloon catheter versus dinoprostone insert for labour induction: a meta-analysis.

To assess the efficacy and safety of a double-balloon catheter versus dinoprostone insert for labour induction. PubMed, MEDLINE, Embase, ClinicalTrials.gov, and the Cochrane Central Register of Clinical Trials databases were searched from 1985 to April 2018. Randomized controlled trials that compared a double-balloon catheter and dinoprostone insert for cervical ripening were identified. Eligible study populations consisted of women with singleton pregnancies that had any indication for labour induction and were randomly assigned to undergo induction with a double-balloon catheter or dinoprostone insert. The main outcomes were incidence of vaginal delivery within 24h and caesarean section, and neonatal outcomes. Five randomized trials (603 women; 305 with a double-balloon catheter and 298 with a dinoprostone insert) were eligible for inclusion. No differences were observed between the two groups in terms of vaginal delivery within 24h [relative risk (RR) 1.21, 95% confidence interval (CI) 0.93-1.59] and incidence of caesarean section (RR 0.99, 95% CI 0.77-1.27). Compared with the double-balloon catheter, the dinoprostone insert was associated with a reduced need for oxytocin administration in the process of labour induction (RR 1.95, 95% CI 1.45-2.62). However, there was a higher incidence of excessive uterine activity (RR 0.17, 95% CI 0.06-0.54) and neonatal umbilical cord arterial blood pH < 7.1 (RR 0.36, 95% CI 0.15-0.84) in the dinoprostone insert group. This review showed that the efficacy of labour induction using both the double-balloon catheter and dinoprostone insert was similar. However, the double-balloon catheter seemed to be a safer method.

Prophylactic infusion of phenylephrine increases the median effective dose of intrathecal hyperbaric bupivacaine in cesarean section: A prospective randomized study.

Background:Phenylephrine infusion to prevent spinal-induced hypotension can attenuate cephalic spread of intrathecal bupivacaine. Therefore, we suspected the intrathecal dose requirement for bupivacaine may differ when using phenylephrine infusion to prevent spinal-induced hypotension in cesarean section. We designed a prospective, randomized study to determine the ED50 of hyperbaric bupivacaine for cesarean section under combined spinal-epidural anesthesia in healthy parturients with and without prophylactic phenylephrine infusion to prevent spinal-induced hypotension.Methods:Sixty healthy parturients rated American Society for Anesthesiology status I/II undergoing elective cesarean section were enrolled in this study, which was conducted July 2016 to February 2017 in the labor and delivery department of Jiaxing University Affiliated Women and Children Hospital. After enrollment, patients were randomized into 2 groups of 30 by blinded opaque envelopes sorted by computer-generated random allocation. Solutions were prepared by an anesthesiologist not involved in outcome measurement. Patients and anesthesiologists collecting data were blinded to group allocation. Group P (phenylephrine group) parturients received prophylactic infusion of phenylephrine at the time of intrathecal injection. Group S (saline group) parturients receive the same volume of saline. Doses of intrathecal bupivacaine for each patient were determined using an up-down allocation method; initial dose was 7 mg. Effective dose was defined as bilateral T6 or above sensory block level achieved within 10 minutes of intrathecal drug administration and no additional epidural lidocaine required for intraoperative pain. The Dixon and Massey formula was used to calculate ED50 values.Results:The ED50 values for hyperbaric bupivacaine were 7.0 mg (95% confidence interval [CI]: 6.6–7.4 mg) and 4.9 mg (95% CI: 4.4–5.4 mg) for groups P and S, respectively (P < .001). There were significant differences in incidence of hypotension and pH of umbilical arterial blood between groups S and P (60% vs 10%, P = .04 and 7.31 ± 0.04 vs 7.28 ± 0.06, P = .003, respectively).Conclusion:The ED50 of intrathecal hyperbaric bupivacaine is higher when phenylephrine infusion is used to prevent spinal-induced hypotension than when it is not used.

The Effect of Prophylactic Phenylephrine and Ephedrine Infusions on Umbilical Artery Blood pH in Women With Preeclampsia Undergoing Cesarean Delivery With Spinal Anesthesia: A Randomized, Double-Blind Trial.

Spinal anesthesia for cesarean delivery is associated with a high incidence of hypotension. Phenylephrine results in higher umbilical artery pH than ephedrine when used to prevent or treat hypotension in healthy women. We hypothesized that phenylephrine compared to ephedrine would result in higher umbilical artery pH in women with preeclampsia undergoing cesarean delivery with spinal anesthesia. This study was a randomized double-blind clinical trial. Nonlaboring women with preeclampsia scheduled for cesarean delivery with spinal anesthesia at Prentice Women's Hospital of Northwestern Medicine were randomized to receive prophylactic infusions of phenylephrine or ephedrine titrated to maintain systolic blood pressure >80% of baseline. Spinal anesthesia consisted of hyperbaric 0.75% bupivacaine 12 mg, fentanyl 15 µg, and morphine 150 µg. The primary outcome was umbilical arterial blood pH and the secondary outcome was umbilical artery base excess. One hundred ten women were enrolled in the study and 54 per group were included in the analysis. There were 74 and 72 infants delivered in the ephedrine and phenylephrine groups, respectively. The phenylephrine:ephedrine ratio for umbilical artery pH was 1.002 (95% confidence interval [CI], 0.997-1.007). Mean [standard deviation] umbilical artery pH was not different between the ephedrine 7.20 [0.10] and phenylephrine 7.22 [0.07] groups (mean difference -0.02, 95% CI of the difference -0.06 to 0.07; P = .38). Median (first, third quartiles) umbilical artery base excess was -3.4 mEq/L (-5.7 to -2.0 mEq/L) in the ephedrine group and -2.8 mEq/L (-4.6 to -2.2mEq/L) in the phenylephrine group (difference -0.6 mEq/L, 95% CI of the difference -1.6 to 0.3 mEq/L; P = .10). When adjusted for gestational age and infant gender, umbilical artery pH did not differ between groups. There were also no differences in the umbilical artery pH stratified by magnesium therapy or by the severity of preeclampsia. We were unable to demonstrate a beneficial effect of phenylephrine on umbilical artery pH compared with ephedrine. Our findings suggest that phenylephrine may not have a clinically important advantage compared with ephedrine with regard to improved neonatal acid-base status when used to prevent spinal anesthesia-induced hypotension in women with preeclampsia undergoing cesarean delivery.

340: Intrapartum hypertension, diagnosis of preeclampsia and adverse neonatal outcomes

The intrapartum diagnosis of hypertension is challenging given blood pressure (BP) measurements in labor may be affected by pain and hemodynamic changes. Our objective was to determine the prevalence of intrapartum hypertension and its clinical relevance. Secondary analysis of an intrapartum fetal heart rate monitoring trial that enrolled women with singleton gestation at >36 weeks gestation, who were attempting vaginal delivery, had ruptured membranes and a cervix 2-7 cm dilated. Women diagnosed with gestational hypertension (GHTN) or preeclampsia (PE) at the time of enrollment, or receiving magnesium sulfate, were excluded from the analysis, as well as those with chronic hypertension, lupus, or BP measured less frequently than every 30 minutes. BP was measured using an automated machine and digitally stored. The prevalence of various degrees of systolic and diastolic BP elevations after enrollment, and their associations with maternal outcomes and a composite neonatal outcome (intrapartum fetal death, neonatal death, Apgar score ≤ 3 at 5’, neonatal seizure, umbilical-artery blood pH ≤ 7.05 with a base deficit ≥ 12 mmol/L, intubation for ventilation at delivery, or neonatal encephalopathy) were determined. The prevalence of the various BP elevations is summarized in Table 1. One or more systolic BP >140 mmHg or diastolic BP >90 mmHg occurred in 64.5% of laboring women, and was not associated with the composite neonatal outcome or cesarean delivery (CD), but was associated with use of magnesium sulfate (MgSO4), and longer maternal length of stay. In addition to the association with the latter maternal outcomes, 2 or more BPs above these cutoffs at least 4 hours apart was also associated with higher CD rates. Multivariate logistic regression showed that when compared to normotensive women, increased BP with or without the diagnosis of GHTN or PE was associated with CD, but not adverse outcomes (Table 2). Two women had seizures after enrollment: one had normal BP but was diagnosed with GHTN /PE and the other had a single BP elevation BP elevations above the cutoffs used to diagnose hypertension are very common in labor and are not associated with adverse neonatal outcomes. They are, however, associated with higher cesarean rates and maternal length of stay, even if they do not lead to diagnosis of GHTN or PE

The Assessment of Association between Uterine Artery Pulsatility Index at 30-34 Week's Gestation and Adverse Perinatal Outcome.

Background:Given the high prevalence of adverse perinatal outcome in the developing countries and the association between uterine artery (UtA) blood flow and fetal status in the uterine, in the current study, we assess the association between UtA pulsatility index (UtA-PI) at 30–34 week's gestation and adverse perinatal outcome.Materials and Methods:This cohort study included 100 pregnant women at 30–34 weeks’ gestation. At baseline, UtA-PI was evaluated with color Doppler through abdominal ultrasound. Then, adverse perinatal outcomes including preterm labor, intrauterine fetal death, preeclampsia, low 5-min Apgar score (<7), low umbilical arterial cord blood pH, admitted to Intensive Care Unit in the first 3 days of birth, low birth weight, infant with low weight, death of newborns, cesarean section for respiratory distress, and meconial amniotic fluid were recorded. Ultimately, the collected data were analyzed using SPSS, version 20.Results:The presence of small-for-gestational-age fetuses indicated the highest prevalent adverse prenatal outcome with the incidence of 13.3% and 58.5%, respectively, among pregnancies with normal UtA-PI as well as those with high UtA-PI (P < 0.001). Overall, given that sensitivity and specificity of high UtA-PI were 37.5% and 73.3%, respectively, it could not properly predict adverse perinatal outcome (P = 0.360).Conclusion:According to the results, although the incidence of some of adverse perinatal outcomes in pregnant women with high UtA-PI was higher compared to those with normal UtA-PI, this factor alone cannot predict adverse perinatal outcome well. Therefore, this factor may predict these outcomes well, in the subgroups with high-risk pregnancies or with some blood factors or with pregnancy complications.

The comparison of umbilical cord arterial blood lactate and pH values for predicting short-term neonatal outcomes

ObjectiveCurrent clinical practice of assessing neonatal condition is based on evaluation of umbilical cord arterial blood pH value rather than lactate. However, evidence shows that lactate is direct and more predictive measurement than pH or at least of equal importance. This study is to assess and compare umbilical cord arterial lactate and pH values for predicting short-term neonatal outcomes. Materials and methodsA retrospective cohort study was conducted at the tertiary level hospital, were arterial umbilical cord blood sampling was collected according to the standard procedures. Neonatal morbidity was registered if at least one of the following conditions was noted: Apgar score at 1 min after delivery was 6 or lower, resuscitation performed, including assisted ventilation and requirement of admission to neonatal intensive care unit. Mothers–newborns pairs were allocated into two groups: newborns exposed to perinatal hypoxia (group 1) and observed as healthy newborns (group 2). Receiver operating characteristics curves (ROC) were generated to assess the predictive ability of pH and lactate for the short-term neonatal outcomes. Results901 neonates born at ≥37 weeks of gestation were included. Newborns exposed to perinatal hypoxia (group 1) encompassed 39 (4.3%) patients, and observed as healthy (group 2) – 862 (95.7%). Arterial umbilical cord blood pH in group 1 was 7.160 ± 0.126 as compared to 7.314 ± 0.083 in group 2; p < 0.001. Mean arterial lactate was significantly higher in group 1 than group 2 (6.423 ± 2.335 as compared to 3.600 ± 1.833; p < 0.001). The difference between areas under ROC curves representing pH and lactate was not significant (0.848 and 0.831 respectively; p = 0.6132). ConclusionUmbilical cord arterial lactate and pH predicted short-term neonatal outcomes with similar efficacies.

Outcome of vaginal birth after cesarean section in women with advanced maternal age

Objective: To explore the perinatal outcome of vaginal birth after cesarean (VBAC) in women with advanced age. Methods: Totally 2 587 women delivered after one or two prior cesarean sections (gestational age≥28 weeks) in the First Affiliated Hospital of Kunming Medical University from July 2013 to February 2017. 909 trial of labor after cesarean(TOLAC) cases of singleton pregnancy with one prior cesarean section were studied retrospectively. According to the age, of the 909 TOLAC cases, 237 were the advanced age group, and 672 cases were the low age group. The maternal and neonatal outcomes between the two groups were compared. Results: The percentage of TOLAC in women with advanced age was 32.4% (237/731), and VBAC rate was 88.2% (209/237). The percentage of TOLAC in younger women was 36.2% (672/1 856), and VBAC rate was 82.4% (554/672). The difference of the TOLAC rate between the two groups was not significant (P>0.05), and the VBAC rate of the advanced age group was higher than the low age group (P<0.05). In the comparison of the two groups, the proportion of bachelor degree or above(55.7%,132/237), the prepregnancy BMI (22.4±3.0) kg/m(2), pregnant interval time (68.5±38.3) months, the proportion of gestational hypertension (8.4%,20/237), the proportion of gestational diabetes(34.6%,82/237) and the rate of the neonatal ICU admission (18.1%,43/237) in the advanced age group were higher than those of the low age group (P<0.05), respectively. And there were no significant differences in the rate of postpartum hemorrhage, the rate of postpartum hemorrhage≥1 500 ml, the rate of postpartum transfusion, puerperal morbidity, neonatal birth weight, neonatal 5 min Apgar score<7 score, umbilical artery blood pH<7.0, neonatal tracheal intubation and respiratory distress syndrome (all P>0.05). In all TOLAC cases, the rate of uterine rupture was 0.11%(1/909) and there was no maternal and neonatal death. Conclusion: VBAC is a safe and feasible way of delivery for singleton pregnancy after one prior cesarean section in women with advanced age.

A Prophylactic Phenylephrine Infusion for Preventing Hypotension during Spinal Anaesthesia for Caesarean Section and to Study its Effects on APGAR Score and Umbilical Artery Blood pH

A Prophylactic Phenylephrine Infusion for Preventing Hypotension during Spinal Anaesthesia for Caesarean Section and to Study its Effects on APGAR Score and Umbilical Artery Blood pH