Vascular contraction of umbilical arteries of pregnant women with preeclampsia.

Objective: Potassium channels have an important role in the vascular adaptation during pregnancy and a reduction in the expression of adenosine triphosphate-sensitive potassium channels (Katp) has been linked to preeclampsia. Activation of Katp induces vasodilation; however, no previous study has been conducted to evaluate the effects of the inhibition of these channels in the contractility of preeclamptic arteries. Glibenclamide is an oral antihyperglycemic agent that inhibits Katp and has been widely used in vascular studies. Methods: To investigate the effects of the inhibition of Katp, umbilical arteries of preeclamptic women and women with healthy pregnancies were assessed by vascular contractility experiments, in the presence or absence of glibenclamide. The umbilical arteries were challenged with cumulative concentrations of potassium chloride (KCl) and serotonin. Results: There were no differences between the groups concerning the maternal age and gestational age of the patients. The percentage of smokers, caucasians and primiparae per group was also similar. On the other hand, blood pressure parameters were elevated in the preeclamptic group. In addition, the preeclamptic group presented a significantly higher body mass index. The newborns of both groups presented similar APGAR scores and weights. Conclusion: In the presence of glibenclamide, there was an increase in the KCl-induced contractions only in vessels from the PE group, showing a possible involvement of these channels in the disorder.

The significance of Syndecan 1, a new marker for endothelial dysfunction, in cases of fetal growth retardation.

PROBLEM: In the current study we aimed to investigate Syndecan 1 (SDC1) levels in pregnant women diagnosed with fetal growth restriction (FGR) and the relationship between SDC1 levels and clinical and doppler parameters in FGR cases associated with endothelial dysfunction, angiogenesis and uteroplacental insufficiency METHOD OF STUDY: A total of 90 pregnant women included in the study, (45 with FGR, 45 healthy control) matched by week of gestation and maternal age. Venous blood samples were collected and plasma concentrations of SDC1 were determined by a specific immunoassay. Doppler examination was performed to evaluate the relationship between the SDC1 levels and placental blood supply. RESULTS: Doppler parameters; mean UtA-PI (p < .001), CPR (p = .002) and CPUR (p < .001) were different between the groups, however MCA PI, umbilical artery PI and umbilical artery S/D were not (p > .05). While gestational age at delivery, birth weight, APGAR score at 1 and 5 min were significantly lower (all, p < .001) in the study group, non-reassure fetal heart rate tracing (p = .09) and NICU admission (p = .02) were significantly higher. SDC 1 level was 2,00 ± 1,47 ng/mL and 2,34 ± 1,12 ng/mL in the FGR and control groups, respectively (p = .008). In the study group SDC 1 level was 1,69 ± 2,00 in those with gestational age below 32 weeks and 2,13 ± 1,18 in those with gestational age above 32 weeks and there was a statistically significant difference between the groups (p = .015). Plasma SDC 1 concentration of 2,1850 ng/mL or less had a sensitivity of 70%, a specificity of 72%, area under the ROC curve .65 (p < .005). CONCLUSIONS: Low maternal plasma SDC1 level may be associated with placental insufficiency and FGR. Low levels of SDC1 may be helpful as a predictor for the development of FGR during gestation.

Fetal external features and morphology of the umbilical cord of wild boars.

This study aimed to describe the gestational and morphological aspects of the fetuses and their respective umbilical cords from two pregnant wild boars (Sus scrofa). Morphological descriptions were provided for 23 fetuses and the gestational ages were estimated through fetal characteristics and formula application. The specimens were fixed in 10% formalin for subsequent macroscopic and microscopic examination. Histological characterization was performed using haematoxylin-eosin (H&E), Masson's trichrome (MT) and Verhöeff's staining techniques. The wild boar fetuses exhibited an estimated gestational age of 55 days (in the larger uterus) and 45 days (in the smaller uterus). They displayed well-developed features consistent with domestic pig fetuses, except for the presence of five pairs of mammae. Additionally, the umbilical cord consisted of two arteries, one vein, an allantoic duct, and a vitelline duct (the latter two identified only microscopically), located in the juxtafetal, intermediate and juxtaplacental portions. The arteries and veins were comprised of endothelium, smooth muscle and collagen fibres, with no elastic fibres observed in the vessel walls. The allantoic duct was lined with simple cuboidal epithelium, while the vitelline duct featured a simple squamous epithelium. In conclusion, the morphological characteristics observed in the examined structures align with the expected patterns for species of the Suidae family. Furthermore, these findings contribute substantially to the morphological characterization of the wild boar, yielding valuable insights into the fetal morphology and the structure of the umbilical cord.

Changes in metabolic acidosis following birth in intensive care unit neonates.

BACKGROUND: Little is known about how and why metabolic acidosis changes within the first six hours of life in intensive care unit neonates. OBJECTIVE: To determine changes in pH and base excess between paired umbilical cord arterial and neonatal arterial blood samples during the first 6 h of life, to identify factors associated with the direction and magnitude of change, and to examine morbidity and mortality in newborns with acidosis at birth or as neonates. STUDY DESIGN: Retrospective cohort study of all deliveries from a single institution between 2016-2020 with paired umbilical cord arterial and neonatal arterial samples obtained within 6 h of life meeting rigorous criteria to ensure sample integrity. The primary outcomes were the direction and magnitude of change of pH and base excess. Multiple factors were assessed for possible correlation with pH and base excess change. The secondary outcome was the association between a composite outcome of death or cerebral palsy and pathologic acidosis (pH ≤ 7.1) at birth or as a neonate. RESULTS: 102 patients met inclusion criteria. Newborn arterial gasses were obtained at a median of 1.5 h (74 % < 2 h). pH improved in 71 % of cases and worsened in 29 %, and base excess improved in 52 % and worsened in 48 %, with wide observed ranges in both parameters. The paired pH and base excess values were moderately (r = 0.38) and strongly (r = 0.63) positively correlated, respectively, but were not correlated with time since birth (r = 0.14). Low birth weight, prematurity or respiratory failure were associated with worsening or less improvement, while worse initial acidosis was associated with greater improvement. Death or survival with cerebral palsy was more common with pathologic acidosis in either cord or newborn sample as compared with those without acidosis (27.3 % vs 3.7 %, p = 0.003), and was more common in those with isolated neonatal acidosis as compared to those without acidosis (50 % vs 3.7 %, p = 0.016). CONCLUSIONS: Changes in pH and base excess occurred over a wide range between delivery and the first newborn blood gas in the first 6 h of life, and we identified several factors associated with direction of change. Metabolic acidosis at birth cannot reliably be inferred from neonatal arterial values. Neonatal acidosis, including acidosis following a normal pH and base excess at birth, was associated with morbidity and mortality.

Expression and influence of KATP in umbilical artery smooth muscle cells of patients with hypertensive disorders of pregnancy.

The objective of this study is to investigate the expression and influence of adenosine triphosphate-sensitive potassium channel (KATP) in human umbilical arterial smooth muscle cells (HUASMCs) of patients with hypertensive disorders of pregnancy (HDP). Western blotting was used to detect the protein expression levels of KATP inwardly rectifying potassium channel (Kir)6.1 and sulphonylurea receptor (SUR)2B subunits in HUASMCs from patients with normal parturients (NP), gestational hypertension (GH), chronic hypertension (CH), preeclampsia (PE) and chronic hypertension with superimposed preeclampsia (CHSP), respectively. There was no significant difference in the protein expression of Kir6.1 subunit in NP group, GH group, CH group, PE group and CHSP group (P > 0.05). The protein expression of SUR2B subunit was gradually decreased in NP group, GH group, CH group, PE group and CHSP group, with statistically significant difference among the groups (P < 0.05). The altered expression level of KATP SUR2B subunit may be involved in the pathogenesis of HDP. The severity of HDP may be related to the degree of decrease of SUR2B subunit.

Hemodynamic changes and perinatal outcome associated with umbilical artery thrombosis: a retrospective study.

OBJECTIVE: Poor fetal and perinatal outcomes in fetuses associated with umbilical artery thrombosis (UAT), such as severe intrauterine growth restriction (IUGR) and intrauterine asphyxia have been reported by some case series. Its hemodynamic impact remains unclear. The aim of this study was to evaluate the hemodynamic changes and perinatal outcome in UAT fetuses with a relatively large sample. METHODS: We included singleton fetuses diagnosed with UAT and with at least one available Doppler evaluation before the end of pregnancy in our center from 2016 to 2023. Fetuses with structural abnormalities and with no follow-up results were excluded. Doppler waveforms from the Umbilical artery (UA), middle cerebral artery (MCA), ductus venosus (DV) and uterine artery (UtA) were routinely evaluated according to ISUOG Practice Guidelines from diagnosis. The same sample of GA-matched normal fetuses with Doppler measurements during the same period were randomly selected as control group. RESULTS: Eighty-nine singleton fetuses with UAT with at least one Doppler evaluation before the end of pregnancy were identified, 13 fetuses with no follow-up results were excluded. After comprehensive prenatal counseling, 14 cases received urgent cesarean section, the remaining 55 cases received expectant management, the median day between GA at diagnosis and end of pregnancy was 13 (5-53) days (range, 2-159). 7 (7/76, 9.2%) cases occurred stillbirth, and the incidence of IUGR and Neonatal Intensive Care Unit (NICU) admission were 18.4% (14/76) and 13.2% (10/76) respectively. 49 fetuses (49/76, 64.5%) combined with Doppler abnormalities. UA abnormalities (35/76, 46.1%) and MCA abnormalities (34/76, 44.7%) were the most changes at presentation. Compared to control group, UA-EDV was significantly increased in UAT fetuses [21.84 (15.59-26.64) vs. 16.40 (12.43-20.70) cm/s, p < 0.001], UA-PI and UA-RI significantly decreased [0.68 (0.57-0.84) vs. 0.92 (0.79-1.11), p<0.001; 0.51 (0.44-0.59) vs. 0.62 (0.55-0.68), p < 0.001, respectively]. Both the MCA-PSV and MCA-EDV were significantly higher in UAT fetuses [54.60 (48.00-61.34) vs. 44.47 (29.66-57.60) cm/s, p < 0.001; 11.19 (7.84-17.60) vs. 8.22 (5.21-12.00) cm/s, p < 0.001, respectively], this led to a lower MCA-PI and MCA-RI. Meanwhile, DV-PIV was significantly higher in UAT fetuses [0.6 (0.47-0.87) vs. 0.45 (0.37-0.55), p < 0.001], CPR and UtA-PI were no significant difference between these two groups. Multivariate logistic regression analysis showed that DV-PIV was an independent risk factor for adverse pregnancy outcomes (OR 161.922, p<0.001), the area under the ROC curve (AUC) was 0.792 (95% CI 0.668-0.917; p < 0.001). CONCLUSION: Our data showed serious adverse pregnancy consequences are combined with UAT fetuses. Hemodynamic changes in UAT fetuses showed the remaining artery for compensation and brain perfusion derangement. With a comprehensive and standardized Doppler evaluation, progression of fetal deterioration may be detailed presented.

Diagnosis of single umbilical artery and risk of foetal congenital malformations by prenatal ultrasound: a retrospective study.

BACKGROUND: Single umbilical artery (SUA) is strongly associated with foetal structural abnormalities; however, the exact pattern of this association has not been described. We aimed to investigate the occurrence of malformations in singleton pregnancies with SUA in China and to study the association between the absent side of the umbilical artery and foetal malformations. METHODS: This was a retrospective study of singleton pregnancies for which routine first-trimester anatomical screening was performed at 11+ 0-13+ 6 gestational weeks and, if the pregnancy continued, a second-trimester scan was performed at 20+ 0-24+ 0 weeks. Data were extracted from records at the referral centre, the Obstetrics and Gynecology Hospital of Fudan University, between January 2011 and April 2019 (n = 47,894). Using logistic regression, the odds ratios (OR) with 95% confidence intervals (CIs) were calculated for malformations associated with SUA. RESULTS: The incidence of SUA in our study was 2.0% (970/47,894). Of all foetuses with SUA, 387 (39.9%) had structural malformations. The malformation type varied, with cardiovascular complications being the most common. A robust association was observed between SUA and oesophageal stenosis or atresia (OR: 25.33), followed by cardiovascular (OR: 9.98-24.02), scoliosis (OR: 18.62), genitourinary (OR: 2.45-15.66), and brain malformations (OR: 4.73-9.12). The absence of the left umbilical artery (n = 445, 45.9%) was consistent with that of the right umbilical artery (n = 431, 44.4%). Furthermore, a significantly higher rate of an absent right than the left umbilical artery (p<0.01) was observed in SUA with foetal abnormalities than in SUA with no malformations. CONCLUSIONS: Overall, we observed a higher risk of various specific malformations in foetuses with SUA, and a strong association between SUA and oesophageal stenosis or atresia. The absence of the right umbilical artery was most common in foetuses with SUA and structural malformations. This study provides a reference for ultrasonographers in conducting foetal structural screening for pregnant women with SUA.

Umbilical artery Thrombosis: A case report of prenatal diagnosis and systematic review of the literature.

Umbilical Artery Thrombosis (UAT) is an extremely rare complication of pregnancy strongly associated with severe fetal distress and death. The pathogenesis is still unclear but it is often associated with anatomical cord abnormalities that leads to blood stasis and thrombosis formation. Other possible risk factors are maternal thrombophilia, autoimmune disease, gestational diabetes, hypertension disorders of pregnancy and Rh-alloimmunization. The most common clinical symptom is the reduction of fetal movements. The diagnosis is histopathological, but it can be suspected by clinical and prenatal ultrasound findings. Generally, the first choice therapy is the immediate delivery with cesarean section. This study reported a case of a spontaneous intrauterine UAT in a low-risk pregnancy and a systematic review of the literature on clinical, ultrasound and histopathological findings of UAT, in order to help clinicians in the diagnostic process and management of this rare complication.

Trends in Apgar scores and umbilical artery pH: a population-based cohort study on 10,696,831 live births in Germany, 2008-2022.

Low Apgar scores and low umbilical arterial (UA) blood pH are considered indicators of adverse perinatal events. This study investigated trends of these perinatal health indicators in Germany. Perinatal data on 10,696,831 in-hospital live births from 2008 to 2022 were obtained from quality assurance institutes. Joinpoint regression analysis was used to quantify trends of low Apgar score and UA pH. Additional analyses stratified by mode of delivery were performed on term singletons with cephalic presentation. Robustness against unmeasured confounding was analyzed using the E-value sensitivity analysis. The overall rates of 5-min Apgar scores < 7 and UA pH < 7.10 in liveborn infants were 1.17% and 1.98%, respectively. For low Apgar scores, joinpoint analysis revealed an increase from 2008 to 2011 (annual percent change (APC) 5.19; 95% CI 3.66-9.00) followed by a slower increase from 2011 to 2019 (APC 2.56; 95% CI 2.00-3.03) and a stabilization from 2019 onwards (APC - 0.64; 95% CI - 3.60 to 0.62). The rate of UA blood pH < 7.10 increased significantly between 2011 and 2017 (APC 5.90; 95% CI 5.15-7.42). For term singletons in cephalic presentation, the risk amplification of low Apgar scores was highest after instrumental delivery (risk ratio 1.623, 95% CI 1.509-1.745), whereas those born spontaneous had the highest increase in pH < 7.10 (risk ratio 1.648, 95% CI 1.615-1.682).          Conclusion: Rates of low 5-min Apgar scores and UA pH in liveborn infants increased from 2008 to 2022 in Germany. What is Known: • Low Apgar scores at 5 min after birth and umbilical arterial blood pH are associated with adverse perinatal outcomes. • Prospective collection of Apgar scores and arterial blood pH data allows for nationwide quality assurance. What is New: • The rates of liveborn infants with 5-min Apgar scores < 7 rose from 0.97 to 1.30% and that of umbilical arterial blood pH < 7.10 from 1.55 to 2.30% between 2008-2010 and 2020-2022. • In spontaneously born term singletons in cephalic presentation, the rate of metabolic acidosis with pH < 7.10 and BE < -5 mmol/L in umbilical arterial blood roughly doubled between the periods 2008-2010 and 2020-2022.

The changing Doppler patterns and perinatal outcomes of monochorionic diamniotic twins with selective fetal growth restriction.

OBJECTIVES: To investigate the clinical outcomes and Doppler patterns changes in monochorionic diamniotic (MCDA) twins with selective fetal growth restriction (sFGR). METHODS: We retrospectively analyzed 362 sFGR cases from January 2010 to May 2016 at a single tertiary referral center. The Doppler waveforms of umbilical artery end-diastolic flow were collected, and all neonates were subjected to an early neonatal brain scan. RESULTS: A total of 66/100 (66 %) type I cases were stable, whereas 25/100 (25 %) cases changed to type II and 9/100 (9 %) changed to sFGR complicated twin-twin transfusion syndrome (TTTS). A total of 48.9 % (22/45) sFGR cases were complicated with polyhydramnios and 30.4 % (7/23) sFGR cases were complicated with oligohydramnios, both of which were progressed to sFGR with TTTS. Mild cerebral injury was significantly associated with Doppler flow abnormalities, earlier gestational age at delivery and type of sFGR diagnosis. Severe cerebral injury was significantly associated with gestational age at delivery (31.6 vs. 34.1, p=0.002) and larger birthweight discordance (43.9 vs. 29.3 %, p=0.011). CONCLUSIONS: Doppler patterns in sFGR can gradually change, with important consequences with regard to management and outcomes. Along with abnormal Doppler findings, earlier occurrence of sFGR and delivery are associated with subsequent neonatal cerebral injury.

Umbilical artery thrombosis risk factors and perinatal outcomes.

PURPOSE: The purpose of this study was to investigate the risk factors for umbilical artery thrombosis (UAT) and the relationship between umbilical artery thrombosis and perinatal outcomes. METHODS: This was a retrospective study that enrolled singleton pregnant women who were diagnosed with umbilical artery thrombosis. The control group recruited pregnant woman with three umbilical vessels or those with isolated single umbilical artery (iSUA) who were matched with umbilical artery thrombosis group. The risk factors and perinatal outcomes were compared between the groups. RESULTS: Preconception BMI (OR [95%CI]: 1.212 [1.038-1.416]), abnormal umbilical cord insertion (OR [95%CI]: 16.695 [1.333-209.177]) and thrombophilia (OR [95%CI]: 15.840 [1.112-223.699]) were statistically significant risk factors for umbilical artery thrombosis. An elongated prothrombin time (OR [95%CI]: 2.069[1.091-3.924]) was strongly associated with the occurrence of UAT. The risks of cesarean delivery, preterm birth, fetal growth restriction, neonatal asphyxia, and intraamniotic infection were higher in pregnancies with UAT than in pregnancies with three umbilical vessels or isolated single umbilical artery (P<0.05). Additionally, the incidence of thrombophilia was higher in pregnant women with umbilical artery thrombosis than those with isolated single umbilical artery (P = 0.032). Abnormal umbilical cord insertion was also found to be associated with an elevated risk of iSUA (OR [95%CI]: 15.043[1.750-129.334]). CONCLUSIONS: Abnormal umbilical cord insertion was the risk factor for both umbilical artery thrombosis and isolated single umbilical artery. The pregnancies with umbilical artery thrombosis had a higher risk of the adverse perinatal outcomes.

Assessment of the cerebroplacental ratio and uterine arteries in low-risk pregnancies in early labour for the prediction of obstetric and neonatal outcomes.

BACKGROUND: The evidence-based management of human labor includes the antepartum identification of patients at risk for intrapartum hypoxia. However, available evidence has shown that most of the hypoxic-related complications occur among pregnancies classified at low-risk for intrapartum hypoxia, thus suggesting that the current strategy to identify the pregnancies at risk for intrapartum fetal hypoxia has limited accuracy. OBJECTIVE: To evaluate the role of the combined assessment of the cerebroplacental ratio (CPR) and uterine arteries (UtA) Doppler in the prediction of obstetric intervention (OI) for suspected intrapartum fetal compromise (IFC) within a cohort of low-risk singleton term pregnancies in early labor. METHODS: Prospective multicentre observational study conducted across four tertiary Maternity Units between January 2016 and September 2019. Low-risk term pregnancies with spontaneous onset of labor were included. A two-step multivariable model was developed to assess the risk of OI for suspected IFC. The baseline model included antenatal and intrapartum characteristics, while the combined model included antenatal and intrapartum characteristics plus Doppler anomalies such as CPR MoM < 10th percentile and mean UtA Doppler PI MoM ≥ 95th percentile. Predictive performance was determined by receiver-operating characteristics curve analysis. RESULTS: 804 women were included. At logistic regression analysis, CPR MoM < 10th percentile (aOR 1.269, 95 % CI 1.188-1.356, P < 0.001), mean UtA PI MoM ≥ 95th percentile (aOR 1.012, 95 % CI 1.001-1.022, P = 0.04) were independently associated with OI for suspected IFC. At ROC curve analysis, the combined model including antenatal characteristics plus abnormal CPR and mean UtA PI yielded an AUC of 0.78, 95 %CI(0.71-0.85), p < 0.001, which was significantly higher than the baseline model (AUC 0.61, 95 %CI(0.54-0.69), p = 0.007) (p < 0.001). The combined model was associated with a 0.78 (95 % CI 0.67-0.89) sensitivity, 0.68 (95 % CI 0.65-0.72) specificity, 0.15 (95 % CI 0.11-0.19) PPV, and 0.98 (0.96-0.99) NPV, 2.48 (95 % CI 2.07-2.97) LR + and 0.32 (95 % CI 0.19-0.53) LR- for OI due to suspected IFC. CONCLUSIONS: A predictive model including antenatal and intrapartum characteristics combined with abnormal CPR and mean UtA PI has a good capacity to rule out and a moderate capacity to rule in OI due to IFC, albeit with poor predictive value.

Ultrasonographic assessment of abnormal fetal growth related to uteroplacental-fetal biometrics and Doppler (U-AID) indices: Protocol for multicenter retrospective cohort study trial.

Fetal growth restriction (FGR) is one of the leading causes of perinatal morbidity and mortality. Many studies have reported an association between FGR and fetal Doppler indices focusing on umbilical artery (UA), middle cerebral artery (MCA), and ductus venosus (DV). The uteroplacental-fetal circulation which affects the fetal growth consists of not only UA, MCA, and DV, but also umbilical vein (UV), placenta and uterus itself. Nevertheless, there is a paucity of large-scale cohort studies that have assessed the association between UV, uterine wall, and placental thickness with perinatal outcomes in FGR, in conjunction with all components of the uteroplacental-fetal circulation. Therefore, this multicenter study will evaluate the association among UV absolute flow, placental thickness, and uterine wall thickness and adverse perinatal outcome in FGR fetuses. This multicenter retrospective cohort study will include singleton pregnant women who undergo at least one routine fetal ultrasound scan during routine antepartum care. Pregnant women with fetuses having structural or chromosomal abnormalities will be excluded. The U-AID indices (UtA, UA, MCA, and UV flow, placental and uterine wall thickness, and estimated fetal body weight) will be measured during each trimester of pregnancy. The study population will be divided into two groups: (1) FGR group (pregnant women with FGR fetuses) and (2) control group (those with normal growth fetus). We will assess the association between U-AID indices and adverse perinatal outcomes in the FGR group and the difference in U-AID indices between the two groups.

Eucapnic pH coupled with arterial cord pH improves hypoxic-ischemic encephalopathy prediction.

OBJECTIVE: To consider the classical use of "pH < 7.0 and/or a base deficiency ≥12 mmol/L" as markers of the risk of neonatal hypoxic-ischemic encephalopathy (HIE), recalling various criticisms of the use of these markers in favor of that of neonatal eucapnic pH, which appears to be a better marker of this risk. METHODS: Fifty-five cases of acidemia with pH < 7.00 were collected from a cohort from the Nice University Hospital with eight cases of HIE. We compared the receiver operating characteristics curves established from the positive likelihood ratio (+LR) for each case of: umbilical cord artery pH (pHa), neonatal eucapnic pH (pH euc-n) in isolation (not matched to pHa), and matched pHa to its own pH euc-n. RESULTS: The areas under the curve (AUC) are identical for pHa and pH euc-n, but AUC for the matched pair pHa-pH euc-n appears superior but non-significant because of the small number in our cohort. However, using the bootstrap method, the partial AUC for a sensitivity greater than 75% indicates the significant superiority (P < 0.01) of the matched pair pHa-pH euc-n approach. CONCLUSION: The originality of this study lies in the use of two methodologic approaches: (1) standardized partial analysis of the AUCs of the pHa curve and that of pHa matched to its own pH euc-n, and (2) bootstrap statistical technique, that allowed us to conclude (P < 0.01) that the combined use of pH measured at the cord coupled with its eucapnic correction is better for diagnosing metabolic acidosis and best predicting the risk of HIE.

Optimization of Annealing and Metal Films Radiofrequency Heating Procedures for Vitrified Umbilical Arteries.

Vitrification is well known for its application in the cryopreservation of blood vessels, which will address the supply-demand imbalance in vascular grafts for the treatment of cardiovascular disease. Thermal stress damage and devitrification injury in umbilical arteries (UAs) require attention and resolution during the vitrification and rewarming process. In this study, we validated several cooling annealing protocols with temperatures (-130 to -100 °C) and annealing duration durations (10-20 s). Among these, the umbilical artery subjected to annealing at -110 °C for 10 s exhibited the most favorable glass transition and retained 93% of its elastic modulus (0.625 ± 0.030 MPa) compared to the fresh group. Extended annealing temperatures and durations can effectively reduce thermal stress damage, leading to improved mechanical properties by minimizing temperature gradients during cooling. Furthermore, three metal radiofrequency methods were utilized for rewarming, including the use of additional metal films and different magnetic field strengths (20, 25 kA/m). Metal radiofrequency (adding an extra metal film for cryoprotectants rewarming, 20 kA/m) achieved faster and more uniform rewarming, preserving the extracellular matrix (ECM), collagen fibers, and elastic fibers without significant differences compared to the fresh group (P < 0.05). Moreover, its preservation of the biomechanical properties of blood vessels was better than that of water bath heating. Theoretical analysis supports these findings, indicating that radiofrequency heating (RFH) with metal films reduces temperature gradients and thermal stresses during arterial rewarming. RFH contributes to the cryopreservation and clinical application of large-lumen biomaterials, overcoming challenges associated with vascular vitrification and rewarming.

Correlation between intrapartum CTG findings and interleukin-6 levels in the umbilical cord arterial blood: A prospective cohort study.

OBJECTIVE: to investigate the correlation between the intrapartum CardioTocoGraphic (CTG) findings "suggestive of fetal inflammation" ("SOFI") and the interleukin (IL)-6 level in the umbilical arterial blood. STUDY DESIGN: prospective cohort study conducted at a tertiary maternity unit and including 447 neonates born at term. METHODS: IL-6 levels were systematically measured at birth from a sample of blood taken from the umbilical artery. The intrapartum CTG traces were retrospectively reviewed by two experts who were blinded to the postnatal umbilical arterial IL-6 values as well as to the neonatal outcomes. The CTG traces were classified into "suggestive of fetal inflammation (SOFI)" and "no evidence of fetal inflammation (NEFI) according to the principles of physiologic interpretation the CTG traces. The CTG was classified as "SOFI" if there was a persistent fetal heart rate (FHR) increase > 10 % compared with the observed baseline FHR observed at the admission or at the onset of labor without any preceding repetitive decelerations. The occurrence of Composite Adverse Outcome (CAO) was defined as Neonatal Intensive Care Unit (NICU) or Special Care Baby Unit (SCBU) admission due to one or more of the following: metabolic acidaemia, Apgar score at 5 min ≤ 7, need of neonatal resuscitation, respiratory distress, tachypnoea/polypnea, jaundice requiring phototherapy, hypotension, body temperature instability, poor perinatal adaptation, suspected or confirmed early neonatal sepsis. MAIN OUTCOME MEASURES: To compare the umbilical IL-6 values between the cases with intrapartum CTG traces classified as "SOFI" and those classified as "NEFI"; to assess the correlation of umbilical IL-6 values with the neonatal outcome. RESULTS: 43 (9.6 %) CTG traces were categorized as "SOFI"; IL-6 levels were significantly higher in this group compared with the "NEFI" group (82.0[43.4-325.0] pg/ml vs. 14.5[6.8-32.6] pg/mL; p <.001). The mean FHR baseline assessed 1 h before delivery and the total labor length showed an independent and direct association with the IL-6 levels in the umbilical arterial blood (p <.001 and p = 0.005, respectively). CAO occurred in 33(7.4 %) cases; IL-6 yielded a good prediction of the occurrence of the CAO with an AUC of 0.72 (95 % CI 0.61-0.81). CONCLUSION: Intrapartum CTG findings classified as "SOFI" are associated with higher levels of IL-6 in the umbilical arterial blood.

Rate of deterioration of umbilical artery Doppler indices in fetuses with severe early-onset fetal growth restriction.

BACKGROUND: Incorporation of umbilical artery Doppler in the surveillance of fetal growth restriction has been shown to reduce the risk of perinatal deaths. Systole/Diastole ratio, Pulsatility Index and Resistance Index are obtained upon Doppler interrogation of the umbilical artery however it is unknown which index predicts more advanced stages of placental deterioration. OBJECTIVE: This study aimed to examine risk factors for the development of absent or reversed end-diastolic velocity and the time intervals of deterioration from normal umbilical artery end-diastolic velocity (indicated by systole/diastole ratio, pulsatility index, or resistance index) to decreased and absent or reversed end-diastolic velocity in fetuses with early-onset severe fetal growth restriction. STUDY DESIGN: This was a retrospective cohort study performed from 2005 to 2020. All singleton pregnancies with severe (estimated fetal weight or abdominal circumference below the third percentile) and early-onset (diagnosed between 20 0/7 and 31 6/7 weeks of gestation) fetal growth restriction were included. Patients with fetal genetic or structural anomalies, suspected congenital infections, absent or reversed end-diastolic velocity at diagnosis, poor pregnancy dating, and absence of follow-up ultrasounds were excluded. Estimated fetal weight, abdominal circumference, and Doppler indices were reviewed longitudinally from diagnosis to delivery. To examine risk factors for absent or reversed end-diastolic velocity, we performed backward stepwise logistic regression and calculated odds ratios with 95% confidence intervals. Kaplan-Meier curves were compared using log-rank tests. RESULTS: A total of 985 patients met the inclusion criteria, and 79 (8%) progressed to absent or reversed end-diastolic velocity. Factors associated with development of absent or reversed end-diastolic velocity included gestational age at diagnosis (adjusted odds ratio, 4.88 [95% confidence interval, 2.55-9.37] at 20 0/7 to 23 6/7 weeks; adjusted odds ratio, 1.56 [95% confidence interval, 0.86-2.82] at 24 0/7 to 27 6/7 weeks compared with 28 0/7 to 31 6/7 weeks) and presence of chronic hypertension (adjusted odds ratio, 2.37 [95% confidence interval, 1.33-4.23]). Rates of progression from diagnosis of fetal growth restriction with normal umbilical artery Doppler to absent or reversed end-diastolic velocity were significant after 4 weeks from diagnosis (5.84% [95% confidence interval, 4.50-7.57]). Regarding the Doppler indices, the progression from normal values to abnormal indices was similar at 1 and 2 weeks. However, the rate of progression from normal to abnormal systole/diastole ratio compared with the rates of progression from normal to abnormal pulsatility index or resistance index was higher at 4 and 6 weeks. Deterioration from abnormal indices to absent or reversed end-diastolic velocity was shorter with abnormal resistance index and pulsatility index when compared with the systole/diastole ratio at 2, 4, and 6 weeks after diagnosis and at 6 weeks, respectively. CONCLUSION: Earlier gestational age at diagnosis and chronic hypertension are considered as risk factors for Doppler deterioration and development of absent or reversed end-diastolic velocity in the umbilical artery. With normal Doppler indices, significant deterioration and progression to absent or reversed end-diastolic velocity is unlikely until 4 weeks after diagnosis. Abnormal systole/diastole ratio seems to appear first. However, abnormal pulsatility index or resistance index was associated with absent or reversed end-diastolic velocity.

Does maternal oxygen administration during non-reassuring fetal status affect the umbilical artery gas measures and neonatal outcomes?

PURPOSE: To clarify whether maternal oxygen administration during vaginal delivery improves umbilical artery (UA) gas measurements and neonatal outcomes. METHODS: Singleton pregnancies requiring operative vaginal delivery or emergency cesarean section (CS) due to non-reassuring fetal status (NRFS) during vaginal delivery at our hospital from 2018 to 2021 were retrospectively investigated. Intrapartum fetal wellbeing was evaluated based on the 5-tier fetal heart rate (FHR) pattern which is a delivery management method widely used in Japan. Operative vaginal deliveries or emergency CS was performed under integrated judgment in NRFS. Patients were divided into the oxygen group to whom oxygen (10 L/min) was supplied by a facemask and the room air group. The UA gas measurements and neonatal outcomes were compared. The oxygen administration was classified by conditions before and after the coronavirus disease 2019 pandemic. As a secondary evaluation, stratification of FHR pattern levels and factors associated with UA pH < 7.15 were examined. RESULTS: A total of 250 patients required obstetric surgical delivery due to NRFS, including 140 (56%) and 110 (44%) in the oxygen and room air groups, respectively. No differences in maternal background factors were found between both groups, except for maternal age. UA gas measurements and neonatal outcomes also showed no significant differences. No significant factors were extracted in the multivariate analysis for UA pH < 7.15. CONCLUSIONS: Trans-maternal oxygen administration for intrapartum NRFS did not affect neonatal cord blood gasses or neonatal outcomes. Thus, routine oxygen administration for intrapartum NRFS may not always be necessary.

The association between fetal Doppler and uterine artery blood volume flow in term pregnancies: a pilot study.

PURPOSE: To investigate the relationship between uterine artery blood volume flow and fetal Doppler indices in term pregnancies. MATERIALS AND METHODS: A prospective observational study in a tertiary-care university hospital was performed between December 2021 and May 2022. We included only term pregnancies that received accurate ultrasound scans until a week before the birth. The uterine artery (UtA) diameter and UtA volume blood flow were estimated and recorded. The volume of each artery was summed to obtain the total uterine artery volume blood flow (QUtA). The following fetal Doppler indices were evaluated: Umbilical artery (UA), middle cerebral artery (MCA), ductus venosus (DV), and cerebroplacental ratio (CPR). Linear regression analysis was performed to investigate the relationship between the QUtA and the fetal Doppler indices. RESULTS: 49 pregnancies were included. The UA pulsatility index (PI) analysis showed a significant association with QUtA (r2=0.40, p=0.01), demonstrating a decrease of the UA PI when the QUtA increased. The same relationship was noted between the UtA mean PI and QUtA (r2=0.41, p=0.005). A weak correlation between the newborn weight and the QUtA was also noted (r2=0.31, p=0.048), with an elevated newborn weight when the QUtA was high. CONCLUSION: This study showed that UA, UtA PI, and birth weight seem to be linked to QUtA. QUtA had an inverse correlation with UA and UtA PI. In addition, increasing the QUtA showed a linear increase in fetal birth weight. These findings could be helpful in high-risk pregnancy management, but additional research is needed to identify how QUtA in the third trimester impacts labor and fetal outcomes.