Umbilical Venous Blood Samples Research Articles

Prolonged Anesthesia Induction to Delivery Time Did Not Influence Plasma Remifentanil Concentration in Neonates.

Remifentanil, in combination with etomidate and sevoflurane, is commonly used in clinics for general anesthesia induction in cesarean section (CS). This study aimed to evaluate the correlation between the induction to delivery (I-D) time and neonatal plasma drug concentration and anesthesia, as well as its effects on neonates. Fifty-two parturients in whom general anesthesia was induced for CS were divided into group A (I-D<8 min) and group B (I-D≥8 min). Maternal arterial (MA), umbilical venous (UV), and umbilical arterial (UA) blood samples were collected at delivery to analyze the remifentanil and etomidate concentrations using liquid chromatography-tandem mass spectrometry. There were no statistically significant differences between the two groups in terms of plasma concentrations of remifentanil in the MA, UA, and UV blood (P > 0.05). The plasma concentration of etomidate in MA and UV was higher in group A than that in group B (P<0.05), whereas the UA/UV ratio of etomidate was higher in group B than that in group A (P<0.05). The Spearman rank correlation test showed no correlation between the I-D time and plasma remifentanil concentration in the MA, UA, and UV plasma (P>0.05). The concentrations of etomidate in the MA and UV were negatively correlated with the I-D time (P < 0.05). Prolonged I-D time did not significantly influence the maternal or neonatal plasma concentration of remifentanil. It is safe to administer remifentanil target-controlled infusion in combination with etomidate and sevoflurane for general anesthesia induction during CS.

Fetal oxygen and glucose utilization of uncomplicated monochorionic twins: Adapting to the intrauterine environment

IntroductionMonochorionic twins (MC) develop under unique intrauterine conditions and show a high risk of compromise during fetal life. Here we describe umbilical vein blood flow (UVBF) and fetal oxygen and glucose utilization in uncomplicated MC twins and investigate possible differences within twin-pairs according to birth-order. MethodsProspective single-center study on 48 uncomplicated MC twins enrolled at the time of elective cesarean delivery. Ultrasound measurements of UVBF for Twin 1 and Twin 2 labelled according to birth-order were performed before spinal anesthesia. Umbilical arterial and venous blood samples were collected for each twin after fetal delivery, and fetal oxygen and glucose deliveries and uptakes were computed. ResultsAll twins were delivered within 2 min from one-another under steady-state conditions at 36.4 weeks of median gestational age (IQR 36.0–37.0). Birthweight and umbilical cord gas analyses were within physiological ranges for all twins. Second-born twins showed significantly lower UVBF, measured before delivery, and lower median birthweight compared to first-borns. Moreover, median values of estimated fetal oxygen and glucose consumption were lower in second compared to first MC twins. DiscussionUncomplicated MC twins show different birthweight, oxygenation and metabolic rates based on their position in utero, hinting at pre-existing conditions possibly deriving by uneven vascular and metabolic distribution of the two placental territories. The innovative findings of this study emphasize the biological uniqueness of these pregnancies and prompt further physiological studies on MC twins and placenta metabolism.

Utilizing umbilical cord blood – Minimizing blood sampling and pain in healthy infants at risk for polycythemia

BackgroundExposure to pain in early life was associated with long term consequences, therefore strategies for minimizing painful procedures in newborns should be employed. The utility and reliability of cord blood CBC was demonstrated before, however data regarding use of cord blood in healthy infants at risk for polycythemia are lacking. MethodsA single-center, paired-sampling prospective laboratory study including all healthy asymptomatic infants born after 36 weeks gestation who were SGA (<2500 g), LGA (>4000 g), or born to mothers with diabetes in pregnancy. Blood count indices were compared between umbilical and neonatal capillary or venous blood samples. In order to predict cut-off values for neonatal polycythemia using umbilical hematocrit, receiver operator curves (ROC) were plotted. ResultsPaired samples were collected from 433 infants. Mean gestational age and birth-weight were 39.0 ± 1.3 weeks and 3489 ± 682 g. Hemoglobin, hematocrit and WBC values were lower in cord blood compared to neonatal, but PLT count was higher. Pearson r showed only modest correlation between peripheral capillary and umbilical or venous Hct - 0.35 (p < 0.001), and 0.44 (p < 0.001), respectively. In order to try and capture clinically significant polycythemia ROC was plotted for hematocrit >70% and <40%. In our cohort, using the calculated cutoff values (>51% and <35%) could have resulted in a decrease of 72% of neonatal blood draws. ConclusionThis analysis should be interpreted with caution, as currently it cannot support the routine use of umbilical samples' hematocrits for making treatment decision in newborns at risk for polycythemia. Further larger studies are needed.

Reference intervals for complete blood count from Umbilical Cord Blood in newborns and comparison with Venous Blood Values.

Background and Objective:Umbilical cord blood which can be obtained by a non-invasive method can be informative about the clinical status of the newborn. It was aimed to establish reference intervals for umbilical cord blood parameters, and to compare complete blood count results between umbilical cord and venous blood samples in this study.Methods:This study was conducted at Medipol University Sefaköy Hospital, Department of Pediatrics, Istanbul, Turkey. A total of 1898 newborns who were born in a two-year period between January 2018 and December 2019 were included in the study. Venous blood samples were taken from 184 of them, and umbilical cord blood samples were taken from 1714 newborns.Results:The percentiles were determined according to gender and delivery method for the hematological parameters of umbilical cord blood. While mean platelet, eosinophil and mean corpuscular volume values were similar between the groups (p>0.05 for each), and significant differences were found between the groups in terms of all other mean hematological parameters (p<0.05 for each).Conclusion:The results of the complete blood count of umbilical cord blood samples can provide reliable information about the newborn. There are significant differences between umbilical cord and venous blood samples in terms of hematological parameters. For these reasons, it is necessary to determine reliable value ranges for umbilical cord blood hematological parameters in newborns. Data of our study can be a guide for further studies and clinicians.

Umbilical Cord Unmeasured Anions and Tissue Acid Levels According to Stewart’s Method in Term Newborn Infants and the Impact of Delivery Mode on these parameters

Aim: To determine the reference values of strong ion difference (SID), effective SID (SIDe), unmeasured anions (UMA), tissue acids (TA), lactate and Chloride-Sodium (Cl-Na) ratio of umbilical cord blood, and to evaluate the impact of delivery mode on these parameters.&#x0D; Methods: This prospective study was performed on healthy term newborn infants that had normal progress throughout the first and second stages of labor during normal spontaneous delivery (NSD) and cesarean section (C/S). Immediately after birth, 1ml and 2 ml of umbilical venous cord blood samples were obtained for blood gas analysis and blood chemistry respectively. The Cl-Na ratio, anion gap (AG), albumin corrected AG (AGCorr), SID, SIDe, UMA and TA were calculated in NSD and C/S groups.. &#x0D; Results: A total of 181 healthy newborn infants were included the study. Fifty-one infants were delivered by NSD and 130 infants by C/S. The pH and PCO2 values were similar in both groups. The mode of delivery had a significant impact on the umbilical cord AG, AGCorr, SID, lactate, UMA, and TA levels. All these values were significantly higher in NSD than C/S group. &#x0D; Conclusion: Umbilical cord blood gas analysis is a common practice to evaluate fetal status at delivery. The calculation of blood gas parameters in perinatal problems according to Stewart’s method may lead further understanding how perinatal conditions of the mother influence the fetus and newborn infant.

Screening of vitamin D and calcium concentrations in neonates of mothers at high risk of vitamin D deficiency

ObjectiveThe aim of this study was to determine, retrospectively, the serum 25OHD and calcium concentrations of screened neonates of mothers at high risk of 25OHD deficiency and examine whether their measurement contributes to the management of these neonates.MethodsSerum 25OHD and calcium concentrations from 600 samples of umbilical cord blood or venous blood collected from neonates over a 12-month period were analysed.ResultsThere was a high prevalence of vitamin D insufficiency (27.6%, 30–50 nmol/L) and deficiency (21.3%, < 30 nmol/L) in neonates from high-risk maternal groups. There was a statistically positive but weak correlation (ρ = 0.22, P < 0.0001) between 25OHD and serum calcium. Only 7 neonates out of 569 (1.2%) had calcium concentrations in the hypocalcaemic range; however, a significant number (47.6%) were reported to be in the hypercalcaemic range. Nearly all of these were venous samples collected in first 24 h after birth.ConclusionVitamin D deficiency is prevalent in neonates of high-risk mothers but the risk of hypocalcaemia due to vitamin D deficiency at birth is low. Screening neonates entails blood testing which can cause distress to neonates and their parents, substantial imposition on staff and financial burden on the health care system. Vitamin D supplementation of these neonates from birth without routine screening appears more reasonable. Also, the data from this study suggest that the paediatric reference range for corrected calcium concentrations in neonates should be re-evaluated.

SUN-083 Screening of Vitamin D and Calcium Concentrations in Neonates of Mothers at High Risk of Vitamin D Deficiency

Objective: The aim of this study was to determine, retrospectively, the serum 25OHD and calcium concentrations of screened neonates of mothers at high risk of 25OHD deficiency (maternal 25OHD < 25 nmol/L or unknown vitamin D concentrations and risk factors for vitamin D deficiency) and critically analyse whether their measurements contributes to the management of these neonates.Methods: Serum 25OHD and calcium concentrations from 600 samples of umbilical cord blood or venous blood collected from neonates over a 12-month period were analysed. 25OHD concentrations were reported for all while both the corrected calcium concentrations and vitamin D concentrations were available for 569 samples.Results: There was little or no evidence of association between neonatal 25OHD concentrations and gender, gestational age or birth weight. There was a high prevalence of vitamin D insufficiency (27.6%, 30–50 nmol/L) and deficiency (21.3%, < 30 nmol/L) in neonates from high-risk maternal groups. There was a statistically positive but weak correlation (ρ = 0.22, P < 0.0001) between serum calcium and 25OHD concentrations. Only 7 neonates out of 569 (1.2%) had calcium levels in the hypocalcaemic range; however, a significant number (47.6%) were reported to be in the hypercalcaemic range. Nearly all of these were venous samples collected in first 24 hours after birth. We calculated the reference interval for corrected calcium from our data of venous samples in first 24 hours and the upper limit was significantly higher (2.38–3.04 mmol/L) than the standard reference range used.Conclusion: Vitamin D deficiency is prevalent in neonates of high-risk mothers but the risk of hypocalcaemia due to vitamin D deficiency at birth is low. Screening neonates entails blood testing which can cause distress to neonates and their parents, substantial impost on staff and financial burden on the health care system. 25OHD deficiency is corrected relatively easily in neonates with supplementation and vitamin D supplementation of neonates from birth without routine screening appears to offer better value of care. Also, the data from this study suggest that the paediatric reference range for corrected calcium concentrations in neonates is higher and the paediatric reference range should be reconsidered.

Maternal and umbilical cord procalcitonin, high-sensitivity C-reactive protein, and interleukin-6 levels in preeclamptic and normotensive patients: A cross-sectional study

To report maternal and umbilical vein levels of procalcitonin (PCT) in patients with preeclampsia (PE) compared to controls. As secondary aims, we measured high-sensitivity C-reactive protein (hs-CRP), and interleukin-6 (IL-6). Moreover, correlation analyses were performed between the inflammatory biomarkers and mean arterial pressure (MAP). This was a single center, cross-sectional study. After Institutional Review Board approval and written informed consent, patients with or without PE were enrolled. PCT, hs-CRP, and IL-6 levels were compared between groups using multiple linear regression models. We calculated the adjusted ratios of geometric means (aRGM) for the comparison of patients with and without PE. Correlation analysis between the inflammatory biomarkers and MAP was performed using Spearman's method. A total of 156 participants were enrolled, yielding 156 venous blood samples and umbilical venous blood samples. Seventy-six patients were in the PE group, and 80 patients were in the control group. Maternal plasma and serum concentrations of PCT (aRGM 3.35 (95% confidence interval [CI]: 2.26, 4.95; p < 0.001)), hs-CRP (aRGM 1.85 (95% CI: 1.30, 2.63; p = 0.003)), and IL-6 (aRGM 1.49 (95% CI: 1.08, 2.04; p = 0.045)) were higher in the PE group. In umbilical venous samples, the concentrations of PCT (aRGM 2.54 (95% CI: 1.46, 4.44; p = 0.003)) and hs-CRP (aRGM 1.45 (95% CI: 1.13, 1.87; p = 0.012)) in the PE group were higher than the controls. No difference in umbilical venous IL-6 concentrations were detected between PE vs. control groups (aRGM 1.46; 95% CI: 1.07, 1.98; p = 0.051). There was positive correlation for both PCT and hs-CRP with MAP in maternal and umbilical venous samples. However, there was no correlation between IL and 6 and MAP in maternal or umbilical venous samples. PCT levels were elevated in maternal and umbilical venous samples of patients with PE, and correlated with disease severity.

Assessment of Mercury in Diagnostic Biomaterials of Different Population Groups in Urban Areas of the Moscow Region

The results of a survey of different population groups in urban areas of the Moscow Region (industry workers, residents of areas with increased anthropogenic load of mercury and conditionally pristine areas, cohorts of pregnant women and children) to assess the contents of mercury in samples of various diagnostic biomaterials taken during the course of research are presented. Mercury concentrations in venous and umbilical cord blood, urine, hair, and nails were determined by means of instrumental neutron activation analysis and cold vapor atomic absorption spectrometry. Peculiarities of selection, transportation, storage, and preparation for analysis of samples of hair, nails, urine and umbilical venous blood are described. The determined concentrations of mercury in the studied diagnostic biomaterials are compared with normal and thresholds values. Although increased mercury concentrations were observed in some cases, no significant exposure of mercury was evident in general in the study towns. A positive correlation between the degree of consumption of seafood during pregnancy and a high content of mercury in the analyzed diagnostic biomaterials was shown.

Effects of mode of delivery on pro-oxidant/antioxidant balance in fetal circulation

Objective: This study was undertaken to assess the influence of mode of delivery on the balance between pro-oxidant/antioxidant systems in fetal circulation. Materials and methods: Both umbilical arterial and venous blood samples were obtained from 37 pregnant women who delivered by spontaneous vaginal delivery (VD group) and from 29 pregnant women who delivered by elective cesarean section (CS group). Oxidative stress and antioxidant activity were evaluated by reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP), respectively. Results: The d-ROMs values of the VD group were higher than that of the CS group in both umbilical arterial and venous blood and these differences were found to be statistically significant (p < .01 and p < .01, respectively). The BAP values of only the umbilical arterial blood were found to be statistically significant (p < .01), with values from the VD group being higher than those of the CS group. In all measurements, the d-ROMs values averaged below 120 CARR U and BAP values averaged above 2200 µmol/L. The ratio of BAP/d-ROMs difference was found to be statistically significant (p < .01) only in the umbilical venous blood, with ratios in the VD group being lower than those in the CS group. Conclusions: Our statistical analyses suggest that vaginal delivery has an effect on increasing oxidative stress as a result of the stress of labor and that an elective cesarean section does not impair the mother’s oxidative stress status. Furthermore, the high BAP values in all the measurements suggest that neonates just after birth have the ability to cope with oxidative stress. Rationale In many studies, the diversity of views on the influence of mode of delivery on the redox status of neonates is likely to be caused by the use of different biomarkers to measure either the oxidative stress, the antioxidant activity, or both. Furthermore, incomplete explanation for sampling cord blood in these studies, either arterial, venous blood or both, complicates matters. To solve the above, this study was designed to assess the effects of mode of delivery on both pro-oxidants, via d-ROMs, and antioxidants, via BAP, in both umbilical arterial and venous blood samples obtained just after birth. There are no existing studies of BAP in both umbilical arterial and venous blood to which we can refer. In conclusion, our study suggests that the pro-oxidant/antioxidant balance in neonates just after birth is better than may be expected when compared to the potentials of adults (including pregnant mothers) according to interpretations of BAP/d-ROMs. This can be understood that neonates may have already been endowed with the ability to cope with oxidative stress, as informed by high BAP values in both umbilical arterial and venous blood. Vaginal delivery may have an effect on increasing oxidative stress as a result of the stress of labors (as measured by d-ROMs), and an elective cesarean section, which has better BAP/d-ROMs in umbilical venous blood than that of vaginal delivery, may not impair the mother’s oxidative stress status.

Correlation Between Maternal and Fetal Insulin Resistance in Pregnant Women with Gestational Diabetes Mellitus.

Offspring of mothers with gestational diabetes mellitus (GDM) are far more likely to develop type 2 diabetes. The aim of this study was to investigate the effect of the insulin metabolism of pregnant women with GDM in late pregnancy on the insulin metabolism of the fetuses and their correlation. This study enrolled 55 pregnant women with GDM and 87 control subjects. Fasting venous blood samples and umbilical venous blood samples (reflecting fetal metabolism) were collected from the study subjects. All blood samples were used to evaluate the blood glucose and insulin concentrations. The blood glucose and insulin concentrations were measured using an automatic biochemical analyser and radioimmunoassay, respectively. The homeostasis model assessment (HOMA) was performed to assess the insulin resistance of mother and fetus. 1. The fasting blood glucose, fasting insulin, and HOMA-IR of pregnant women in the late pregnancy GDM group were all significantly higher than those in the control group (fasting blood glucose: 4.70 ± 0.11 vs. 4.11 ± 0.05 mmol/L, p < 0.001; fasting insulin: 44.1 ± 6.76 vs. 25.1 ± 3.58 µU/mL, p = 0.013; HOMA-IR: 8.92 ± 1.25 vs. 5.39 ± 0.83, p = 0.012); 2. The results of logistic regression analyses showed that maternal age, pre-pregnancy body mass index (BMI), and family history of diabetes were high-risk factors for the development of GDM in pregnant women. 3. The insulin level and HOMA-IR in the umbilical venous blood of the late pregnancy GDM group were both significantly higher than those in the control group (insulin: 10.1 ± 1.41 vs. 6.38 ± 0.49 µU/mL, p = 0.035; HOMA-IR: 1.60 ± 0.22 vs. 1.07 ± 0.08, p = 0.006). 4. The umbilical venous blood HOMA-IR in the GDM group positively correlated with the maternal HOMA-IR and fasting insulin level. The neonatal ponderal index (PI) in the GDM group positively correlated with the umbilical venous blood HOMA-IR and insulin level. The HOMA-IR was significantly higher in the late pregnancy GDM women and their fetuses than in the control group. In addition, fetal HOMA-IR positively correlated to maternal HOMA-IR in late pregnancy GDM women.

A comparative analysis of maternal and fetal 25-hydroxyvitamin D in pregnant women with and without gestational diabetes mellitus

Objective: This study aimed to compare maternal 25-hydroxyvitamin D (25(OH)D) serum levels during pregnancy in women with and without gestational diabetes mellitus (GDM) with neonatal 25(OH)D serum levels and to evaluate the relationship between maternal and fetal 25(OH)D in the two groups.Methods: Between May 2014 and March 2015, 87 pregnant women were enrolled. The study population was divided into two groups, those with and without GDM (n = 32 and 55). All participants were surveyed about lifestyle and behavior. Maternal and umbilical venous blood samples were obtained. Serum from maternal blood was analyzed for 25(OH)D2 and 25(OH)D3, and umbilical venous blood for 25(OH)D2, 25(OH)D3, and 3-epi-25(OH)D3.Results: The maternal serum level of 25(OH)D3 and the 25(OH)D3 and 3-epi-25(OH)D3 levels in umbilical venous blood were significantly lower in women with GDM (p < .01 for all comparisons). The maternal blood levels of 25(OH)D2, 25(OH)D3, and total 25(OH)D were positively correlated with their levels in umbilical venous blood in the total, normal, and GDM groups.Conclusions: The serum 25(OH)D3 and 3-epi-25(OH)D3 levels of babies from mothers with GDM are lower than in pregnant women without GDM.

Providing Oral Nutrition to Women in Labor: American College of Nurse-Midwives.

Historically, oral intake for women during labor has been limited to nothing by mouth or clear liquids only. These restrictions are based on the risk of aspiration during or after the administration of general anesthesia. While aspiration can be life threatening, older methods of anesthesia are rarely used in current intrapartum care, and evidence is inconclusive that withholding oral nutrition reduces the risk of gastric aspiration. Additionally, withholding oral nutrition may result in the development of ketosis and may potentially contribute to a woman's stress and dissatisfaction with the birth experience. The purpose of this Clinical Bulletin is to review the evidence related to this practice and provide recommendations to promote informed, shared decision making regarding oral intake during labor with women at low risk for gastric aspiration.

Cardiovascular biomarkers in paired maternal and umbilical cord blood samples at term and near term delivery

BackgroundCardiovascular biomarkers might help to identify fetuses or pregnancies at risk. AimTo examine the umbilical cord neonatal and maternal levels of cardiovascular biomarkers at the time of delivery, and to correlate maternal and fetal biomarker levels to each other, to gestational age and to delivery mode. Study designIn a prospective, observational, cross-sectional, single-center study biomarkers were measured in paired maternal and umbilical venous cord blood samples. SubjectsThe sample cohort included 66 sets of fetal and maternal blood samples (11 after multiple gestation, 53 after cesarean section, 17 after exposure to labor). Outcome measuresMidregional pro-adrenomedullin (MRproADM), midregional-pro atrial natriuretic peptide (MRproANP), brain natriuretic peptide (BNP), n-terminal-pro brain natriuretic peptide (NTproBNP), copeptin, and high sensitive troponin I (hsTnI) levels were measured. ResultsMean±SEM for biomarker levels in umbilical venous/maternal blood were: MRproADM [nmol/L] 1.02±0.04/1.24±0.08, MRproANP [pmol/L] 215.53±12.96/54.65±3.41, BNP [pg/mL] 32.02±3.37/19.76±3.29, NTproBNP [pg/mL] 1228.94±91.73/71.48±8.65, copeptin [pmol/L] 103.42±22.89/10.41±1.71, and hsTnI [pg/mL] 13.54±5.17/4.91±2.37. Fetal MRproANP, NTproBNP, and BNP were inversely correlated with gestational age. Maternal and fetal MRproANP (r=0.472, p=0.002) and copeptin (r=0.572, p<0.001) levels were correlated, whereas there was no feto-maternal correlation for the other biomarkers. Fetal copeptin was elevated after exposure to labor. ConclusionsBiomarker levels appear to be regulated independently in mother and fetus. Fetal biomarkers are influenced by gestational age and delivery mode. In this study on term and near term pregnancies without specific fetal pathology, correlation between paired maternal and fetal biomarker levels was weak or not demonstrable.

3: Umbilical Cord Blood Levels of Endothelial Progenitor Cells and Vascular Endothelial Growth Factor and Risk of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD), a chronic lung disease of prematurity, is currently considered a disease of abnormal vascular and alveolar growth. Mechanisms involved in impaired lung vascular development are poorly understood. Both endothelial progenitor cells (EPCs) and vascular endothelial growth factor (VEGF) are important factors in normal vascular development. To test the hypothesis that in infants delivered at <32 weeks gestation, umbilical cord blood levels of EPCs and VEGF are lower in infants who develop BPD as compared to infants who do not develop the disease. Umbilical venous cord blood samples were obtained within 30 minutes of birth. EPCs were measured using flow cytometry and were defined as cells expressing the surface markers CD-34, CD-133 and vascular endothelial (VE) cadherin with more mature endothelial cells defined as expressing CD-34 and VE cadherin. VEGF was measured using a quantitative sandwich enzyme linked immunoassay. BPD was defined as oxygen dependency at 36 weeks postmenstrual age. Exclusion criteria included chromosomal and congenital abnormalities. Mann-Whitney test was used for continuous variables and the χ2 or Fisher's exact test for dichotomous data. Multivariate logistic regression was performed to estimate the odds ratio (OR) for development of BPD. A P<0.05 was considered statistically significant. There was no effect of mode of delivery, chorioamnionitis or preeclampsia on EPC numbers. Levels of EPCs or VEGF at birth did not affect the risk of development of BPD in our group of premature infants. Further studies are needed before these cells and VEGF can be considered as biomarkers for prediction of BPD. RESULTS Data reported as median for continuous variables. IQR Interquartile range; NS Nonsignificant RESULTS Data reported as median for continuous variables. IQR Interquartile range; NS Nonsignificant

Glyburide transport across the human placenta.

To estimate the magnitude of transplacental transfer of glyburide in women with gestational diabetes mellitus (GDM). A prospective, observational study was conducted on women with GDM on glyburide therapy. On delivery admission, the glyburide dose and time of last dose were recorded. Immediately postdelivery, maternal and umbilical venous blood samples were obtained and the concentrations of glyburide were determined by high-performance liquid chromatography-mass spectrometry with a limit of detection of 0.25 ng/mL. Nineteen patient dyads were analyzed. The mean total daily maternal glyburide dose was 6.6±6.3 mg per day and the mean time between last dose and sampling was 13.3±6.5 hours. The mean maternal serum glyburide level at birth was 15.4±20.8 ng/mL, whereas the mean umbilical glyburide level was 7.5±8.2 ng/mL, which showed a statistical correlation (r=0.72, P<.01). There were statistically significant relationships between total maternal glyburide dose (1.25-20 mg per day) and maternal glyburide levels (0.93-70.71 ng/mL; r=0.46, P≤.01) and between total maternal glyburide dose and umbilical glyburide levels (0.95-32.41 ng/mL; r=0.43, P≤.01) However, we observed wide variability in maternal and umbilical glyburide levels at both extremes of the total glyburide dose. Seventy-nine percent of cord samples (15/19) had glyburide levels less than 10 ng/mL (the limit of detection reported in earlier studies) and 37% (7/19) were higher than the corresponding maternal samples. Transplacental transfer of glyburide is highly variable among patients, corroborating ex vivo placental perfusion studies showing a transport-mediated glyburide efflux from the fetal to the maternal circulation. In most neonates (79%), glyburide levels were below 10 ng/mL. III.

Effect of Different Phenylephrine Bolus Doses for Treatment of Hypotension during Spinal Anaesthesia in Patients Undergoing Elective Caesarean Section

The efficacy of phenylephrine might be improved by giving doses higher than that traditionally used (100 µg). This study compared the effects of three initial bolus doses of intravenous phenylephrine; 100 µg (group P100), 125 µg (group P125) and 150 µg (group P150), for the treatment of post-spinal hypotension in patients undergoing elective caesarean delivery. If hypotension was not corrected by this dose, additional boluses of 25 µg were given every minute. Further hypotensive episodes were treated with half the initial bolus dose, followed by 25 µg boluses, as required. Umbilical arterial and venous blood samples were obtained for blood gas analysis and Apgar scores recorded. One hundred and twenty subjects (40 per group) who developed post-spinal hypotension (75%) were included in this randomised, double blind trial. Although systolic blood pressure was higher at certain time-points after 150 µg phenylephrine, there were no statistically significant differences in the effectiveness of the first bolus of phenylephrine to treat hypotension (85%, 95% and 95% in groups P100, P125 and P150, respectively, P=0.215); the additional dose of phenylephrine after the first bolus (P=0.810); the number of additional boluses (P=0.318) or of hypotensive episodes (P=0.118). There were no significant differences in the number of patients developing reactive hypertension or bradycardia, in maternal side-effects or in neonatal outcomes. Although the study may have been underpowered, initial phenylephrine bolus doses of 100 µg, 125 µg and 150 µg did not significantly differ in efficacy to treat post-spinal hypotension in these patients.

Effects of Maternal Supplementary Oxygen on the Newborn for Elective Cesarean Deliveries Under Spinal Anesthesia

The aim of this investigation was to determine whether supplementary oxygen provided by either nasal cannula or face mask versus room air might affect fetal oxygenation during elective cesarean section under spinal anesthesia by assessing maternal and neonatal regional cerebral oxygenation (rSO2) with a cerebral oximeter. Ninety parturients were randomly allocated into three groups: two groups received 5 L/min oxygen by either nasal cannula (Group NC, n = 30) or face mask (Group FM, n = 30), respectively, and the third group was allowed to breathe room air (Group RA, n = 30). After maternal mean arterial pressure, heart rate and peripheral oxygen saturation had been monitored, rSO2 was determined by cerebral oximeter. Umbilical artery (UA) and venous (UV) blood samples were collected for blood gas analysis. Neonatal rSO2 and Apgar scores were recorded. The mean maternal rSO2 which was recorded 3 and 5 min after administration of the spinal block in Group FM was lower than that of Group NC (p = 0.033 and 0.042, respectively). Neonatal rSO2, UA pH, UV pH and UA base excess (BE) were lower in Group FM than in the other groups (p < 0.05). The Apgar score (1 min) in Group FM was lower than that of Group RA (p = 0.046). The effect of maternal supplementary oxygen on the newborn has been demonstrated by a cerebral oximeter monitor and supported by umbilical cord blood gas analysis and Apgar scores.

Trace elements’ concentrations in maternal and umbilical cord plasma at term gestation: a comparison between active labor and elective cesarean delivery

Objective. Trace elements are minerals required in minute quantities to maintain proper physical functioning. The role of trace elements in the process of parturition is poorly understood. This study was aimed to determine levels of trace elements’ concentration in maternal plasma and umbilical venous and arterial plasma at term during active labor vs elective cesarean delivery (CD).Study design. A prospective case–control study was conducted. Forty healthy parturients in active labor at term with their newborns were compared to 40 healthy parturients matched for maternal age, parity, and gestational age, who delivered by elective CD (before commencement of labor). Samples of maternal venous blood and umbilical cord arterial and venous blood were drawn immediately following delivery. Trace elements’ concentrations were measured using the inductively coupled plasma mass spectrometer (ICP-MS).Results. Significant higher levels of manganese (Mn) and selenium were found in maternal venous plasma during active labor vs elective CD. Magnesium (Mg) levels were significantly higher in maternal venous blood during elective CD compared to active labor. Umbilical cord artery levels of Mg, Mn, and zinc (Zn) were significantly higher in active term labor vs elective CD. Also, significant higher levels of copper and Zn were found in umbilical cord vein between active labor and elective CD.Conclusion. Trace elements’ concentrations differ significantly in fetal blood during active labor vs elective CD. Hence, trace elements may play a crucial role in the process of human parturition.

Effects of maternal supplementary oxygen on the newborn for elective cesarean deliveries under spinal anesthesia

The aim of this investigation was to determine whether supplementary oxygen provided by either nasal cannula or face mask versus room air might affect fetal oxygenation during elective cesarean section under spinal anesthesia by assessing maternal and neonatal regional cerebral oxygenation (rSO(2)) with a cerebral oximeter. Ninety parturients were randomly allocated into three groups: two groups received 5 L/min oxygen by either nasal cannula (Group NC, n = 30) or face mask (Group FM, n = 30), respectively, and the third group was allowed to breathe room air (Group RA, n = 30). After maternal mean arterial pressure, heart rate and peripheral oxygen saturation had been monitored, rSO(2) was determined by cerebral oximeter. Umbilical artery (UA) and venous (UV) blood samples were collected for blood gas analysis. Neonatal rSO(2) and Apgar scores were recorded. The mean maternal rSO(2) which was recorded 3 and 5 min after administration of the spinal block in Group FM was lower than that of Group NC (p = 0.033 and 0.042, respectively). Neonatal rSO(2), UA pH, UV pH and UA base excess (BE) were lower in Group FM than in the other groups (p < 0.05). The Apgar score (1 min) in Group FM was lower than that of Group RA (p = 0.046). The effect of maternal supplementary oxygen on the newborn has been demonstrated by a cerebral oximeter monitor and supported by umbilical cord blood gas analysis and Apgar scores.