Arterial Cord Research Articles

Analysis of umbilical cord blood gas in term and near term asphyxiated newborn babies

Introductions: Birth asphyxia is failure breathing causing severe consequences or death. This study aims to determine the incidence of perinatal asphyxia in neonates with low Apgar and Hypoxic Ischemic Encephalopathy (HIE) in asphyxiated babies.
 Methods: This was a cross sectional study from November 1, 2010 to July 30, 2011. Babies with Apgar score of less than seven at five minute were enrolled in the study. Blood was drawn from umbilical cord artery for blood gas analysis. Neonates were followed up in every six hours for at least 48 hours. Staging of HIE according to Sarnat staging was done in babies with Apgar score of <7 at five minutes within 24 hours of birth. Data was analysed using SPSS version 16.0.
 Results: Total of 2,425 live births, 56 (2.30%) were born with an Apgar of < 7 at five minute, six were excluded (due to set exclusion criteria) and remaining 50 were analysed. Thirty-four (68% of 50) of babies with low Apgar score had maternal risk factors – meconium stained liquor being the commonest risk factor. Majority (46%) had cord blood pH of >7.2, 40% had between 7.1 to 7.2, 12% between 7 to 7.1 and remaining 2% had pH < 7. HIE developed in 22% (11/50) of the asphyxiated babies.
 Conclusions: More than 1/3rd (46%) of babies with low Apgar had low cord blood pH, 1/4th (26%) had base excess, and 22% developed features of HIE. Cord blood pH were better predictors than Apgar in asphyxiated babies.

Effect of inter-twin delivery interval on umbilical artery pH and Apgar score in the second twin.

To examine the effect of inter-twin delivery interval on umbilical artery pH and Apgar score of the second twin after vaginal delivery of the first twin. Retrospective study conducted at a single teaching hospital. All pregnant women with twin gestation who delivered the first twin vaginally at more than 24weeks between 1995 and 2015 were included. Major malformations and intrauterine deaths of one or both twins were excluded. Women were divided into those who had an inter-twin delivery interval of less than 30 minutes (group 1) or 30 minutes or more (group 2). Primary outcome was umbilical artery pH less than 7.1 and/or Apgar score less than 7 at 5minutes of the second twin. Generalized linear regression with log was performed to evaluate the association with delivery interval. Of 88145 deliveries during this period, 1955 (2.2%) were twins. Overall, 713 twin pregnancies, 596 (83.6%) in group 1 and 117 (16.4%) in group 2, were eligible and included. Mean inter-delivery interval was 11.0±6.5 and 52.5±31.5minutes in groups 1 and 2, respectively. After adjusting for variables found significantly different between the groups in univariate analysis, inter-delivery interval of less than 30 minutes or 30 minutes or more was not a significant risk factor for pH less than 7.1 and/or Apgar less than 7 (P=.91). The cesarean rate for delivery of the second twin after vaginal delivery of the first twin was 4.3% overall, with a higher rate among group 2 compared with group 1 (18.2% and 3.2%, respectively; P=.001). The second twin's Apgar score and cord artery pH are probably not affected when the inter-twin delivery interval exceeds 30minutes.

The outcomes and risk factors of fetal bradycardia associated with external cephalic version

Objective: The objective of this study is to assess the outcomes and risk factors of fetal bradycardia after external cephalic version (ECV).Methods: We performed a retrospective study of women who underwent ECV after 35 weeks of gestation in 2010–2016. We assessed the birth outcomes, including umbilical cord artery pH, according to the duration of fetal bradycardia and the risk factors for bradycardia.Results: Among 390 cases, 189 (48.5%) cases showed fetal bradycardia during or immediately after ECV. The duration of fetal bradycardia was <1 min (n = 82, 43.4%), <5 min (n = 168, 88.9%); and <10 min (n = 186, 98.4%). All cases showed a good prognosis. Fetal bradycardia lasting >10 min occurred in three cases; emergency cesarean section was performed in each case, with delivery after 12–4 min of bradycardia. Two of three cases showed low Apgar scores at 5 min, with an umbilical cord arterial pH of <7.1. Lower maternal BMI and a prolonged ECV procedure were significantly associated with bradycardia (p for trend: .016 and .015, respectively).Conclusions: Fetal bradycardia lasting >10 min after ECV was a risk factor for asphyxia. Thus, delivery should be completed within 10 min after bradycardia. A low maternal BMI and a prolonged ECV procedure were risk factors for bradycardia after ECV.

Application of guide combined with probing the internal wall of pedicle screw trajectory for subaxial cervical pedicle screw placement

To investigate the skill and evaluate the accuracy for application of guide combined with probing the internal wall of pedicle screw trajectory for subaxial cervical pedicle screw placement. Subaxial cervical pedicle screw was inserted in 11 patients by the guide combined with probing the internal wall of pedicle screw trajectory from January 2014 to October 2016, including 7 males and 4 females with an average age of 48.1 years(ranged 32 to 63 years). There were 4 cases with cervical spondylotic myelopathy, 4 with fracture and dislocation of cervical vertebrae, 1 with cervical cord injury without fracture and dislocation, and 2 with atlantoaxialfracture and dislocation. The target pedicle's diameter, optimal entry point, sagittal angle and cross-sectional angle were measured by CT before operation. During operation, the pedicle screw inserted angle was controlled by a guide with a self-designed protractor and probed the internal wall of pedicle screw trajectory as medial safety margin of insertion screw. The accuracy of cervical pedicle screw was evaluated by CT with classification of four grades and assessed whether there was injury of spine cord or vertebral artery postoperatively. Seventy-one cervical pedicle screws were placed among 11 patients, and no one had been found with clinical manifestations of injury of spine cord (or nerve root) or vertebral artery after operation. According to postoperative CT scan for evaluating the grade of screw position, 52 screws were in grade 0, 13 in grade 1, 4 in grade 2, 2 in grade 3, and 91% (65/71) located in good position. In total, 6 screws were incorreted in placement, and 4 cases of them broke medial wall and 2 cases broke lateral wall. The method of probing the internal wall of pedicle screw trajectory for subaxial cervical pedicle screw placement is safe and reliable, but the studying curve is long. Probing the internal wall of pedicle screw trajectory and controlling the insertion angle by guide with a protractor are key points of this technology.

Umbilical cord bilirubin as a predictor of neonatal jaundice: a retrospective cohort study

BackgroundHyperbilirubinaemia is a major cause of neonatal morbidity. Early identification of those infants most at risk might allow the development of targeted primary preventative therapy and follow-up. The objective of this study was to assess whether arterial umbilical cord bilirubin (aUCB) level at delivery predicts the development of neonatal jaundice in term deliveries.MethodsRetrospective analysis of hospital biochemistry records identified term deliveries with recorded aUCB. Infant medical records were reviewed to identify those who developed neonatal hyperbilirubinaemia (requiring treatment according to UK NICE guidelines) with/without a positive direct antiglobulin test (DAT).ResultsOf 1411 term deliveries with a clearly recorded aUCB, 30 infants developed clinically-significant jaundice (2.7%), of whom 8 were DAT + ve (0.6%) mostly due to ABO incompatibility. aUCB strongly predicted the development of DAT + ve jaundice (area under the ROC curve = 0.996), as well as all-cause jaundice (area under the ROC curve = 0.74). However, this effect was critically dependent on maternal blood group. Amongst infants at risk of ABO incompatibility (maternal blood groups O + ve/O-ve, 39.7%) the predictive value of aUCB for all cause jaundice was strengthened (area under the ROC curve = 0.88). Amongst those not at risk (defined maternal blood group not O + ve/O-ve, 51.0%) it disappeared completely (area under the ROC curve = 0.46). A cutoff of 35 μmol/l for mothers with blood group O + ve/O-ve increased the pre-test probability for all-cause jaundice of 4% to a post-test probability of 30%.ConclusionsFor infants of mothers with blood group O, aUCB predicts development of neonatal jaundice. There was no evident utility for infants of mothers with other blood groups. Estimation of aUCB should be considered as a strategy for early identification of those at risk of neonatal haemolytic jaundice.

Spinal cord injury as a complication of thoracic endovascular aneurysm repair.

Spinal cord ischemia (SCI) is a devastating complication of thoracic aortic aneurysm repair in the era of thoracic endovascular aneurysm repair (TEVAR). This review aims to clarify the causes of SCI during TEVAR and to propose ways that it may be prevented. We performed an extensive literature search of SCI during TEVAR. Based on the existing literature, we examined the anatomy of the anterior spinal cord artery, which supplies blood to the anterior aspect of the spinal cord, and discuss reported effective ways to prevent SCI during TEVAR, including augmentation of arterial blood pressure and drainage of cerebrospinal fluid. After reviewing the mechanism of SCI during TEVAR, we evaluated promising preventative measures.

Evaluation of Mineral Concentrations in Maternal Serum Before and After Birth and in Newborn Cord Blood Postpartum\u2014Preliminary Study

The mineral levels in maternal serum change during pregnancy and may be correlated with those of newborn cord blood. The aim of this study was to evaluate the concentrations of calcium (Ca), magnesium (Mg), zinc (Zn), iron (Fe), and copper (Cu) in maternal blood before and after delivery and in umbilical cord vein and artery serum. The study was carried out in 64 Caucasian pregnant women who delivered in a district hospital in Greater Poland region, aged 28.1 ± 5.4 years, with a mean gestational age of 39.2 ± 1.3 weeks. Blood samples were taken from women 2–8 h before delivery and immediately after childbirth. The umbilical cord artery and vein blood of newborns was obtained immediately after childbirth. The levels of minerals in serum were determined by flame atomic absorption spectrometry. A significant drop in the concentrations of Mg (17.71 ± 1.51 vs 17.07 ± 1.61 μg/ml; p < 0.007), Fe (1.08 ± 0.46 vs 0.82 ± 0.35 μg/ml; p < 0.0004), and Zn (0.63 ± 0.17 vs 0.46 ± 0.16; p < 0.0001) in maternal serum was found after delivery. Moreover, higher levels of Ca, Fe, and Zn and lower levels of Cu were observed in the umbilical vein (Ca: 102.80 ± 7.80 μg/ml; p < 0.0001, Fe: 1.96 ± 0.43 μg/ml; p < 0.0001, Zn: 0.65 ± 0.16 μg/ml; p < 0.0001, Cu: 0.36 ± 0.09 μg/ml; p < 0.0001) and in the umbilical artery cord blood (Ca: 98.07 ± 8.18 μg/ml; p < 0.0001, Fe: 1.63 ± 0.30 μg/ml; p < 0.0001, Zn: 0.65 ± 0.15 μg/ml; p < 0.0001, and Cu: 0.36 ± 0.10 μg/ml; p < 0.0001) compared to the maternal serum (Ca: 85.05 ± 10.76 μg/ml, Fe: 0.82 ± 0.35 μg/ml, Zn: 0.46 ± 0.16 μg/ml, and Cu: 1.90 ± 0.35 μg/ml). Fe levels in the cord artery serum negatively correlated with blood loss during delivery (R = −0.48; p = 0.01), while the Ca concentration in the maternal serum after birth decreased with the age of the women (R = −0.25; p = 0.03). In conclusion, it seems that the process of birth alters the mineral levels in pregnant women’s blood. Moreover, it was found that blood loss and the age of the mother are associated with mineral concentrations in the maternal serum and cord artery blood.

Protein S100B in umbilical cord blood as a potential biomarker of hypoxic-ischemic encephalopathy in asphyxiated newborns

BackgroundNeonatal hypoxic ischemic encephalopathy (HIE) is a devastating condition resulting from a sustained lack of oxygen during birth. The interest in identifying a relevant biomarker of HIE has thrown into limelight the role of protein S100B as a clinical diagnostic marker of hypoxic brain damage in neonates. AimsTo evaluate the diagnostic value of protein S100B, measured in umbilical cord blood immediately after birth, as a useful biomarker in the diagnosis of HIE Sarnat stages II-III as well as a marker for long-term mortality and morbidity. Study designProtein S100B was analyzed in cord blood sampled at birth from 13 newborns later diagnosed with stage II-III HIE and compared with 21 healthy controls. S100B concentrations were related to cord artery pH, amplitude-integrated electroencephalography (aEEG), stage of HIE, and death/sequelae up to an age of 6years. Both parametric and non-parametric statistics were used with a two-sided P<0.05 considered significant. ResultsThe difference in S100B concentration was marginally statistically significant between HIE cases and controls (P=0.056). Cord blood acidosis (P=0.046), aEEG pattern severity (P=0.030), HIE severity (P=0.027), and condition at 6-year follow-up (healthy/permanent sequelae/death; P=0.027) were all related to an increase in S100B concentration. ConclusionsProtein S100B in neonates suffering from HIE stages II-III appeared elevated in umbilical cord blood at birth. The S100B concentrations were positively associated to the severity of disease and the risk of suffering from neurodevelopmental sequelae and even death.

Obstetric risk factors for poor neonatal adaptation at birth

Purpose: To identify obstetric risk factors of delivering a neonate with poor neonatal adaptation at birth. Material and methods: Nested case–control study. Poor neonatal adaptation was defined for presence of at least: umbilical cord artery pH <7.10, base deficit ≥12 mmol/L, Apgar score at 1′ ≤5. Controls were selected from the same population and matched with cases. The association between clinical parameters and poor neonatal adaptation was analyzed by logistic regression. Results: One hundred and thirty three women (2.1% of all live births) with a neonate presenting a poor neonatal adaptation were matched with 133 subsequent controls. Significant contributions for the prediction of poor neonatal adaptation were provided by maternal age ≥35 years (p ≤ .001, odds ratio (OR) 3.9 [95%CI: 2.3–6.8]), nulliparity (p ≤ .001, OR 3.3 [95%CI: 1.8–6]), complications during pregnancy (p = .032, OR 2.2 [95%CI: 1.1–4.4]), gestational age at delivery <37 weeks (p = .008, OR 5.2 [95%CI: 1.5–17.8]) and cardiotocography category II or III (p ≤ .001, OR 36.3 [95%CI: 16.5–80.1]). The receiver operative characteristic curve was 0.91 [95%CI: 0.87–0.95], and detection rates 82.7% and 89.5% at 10% and 20% of false positive rates, respectively. Conclusions: Several obstetric risk factors before and during labor can identify a subgroup of newborns at higher risk of a poor neonatal adaptation at birth.

Investigating pH based evaluation of fetal heart rate (FHR) recordings

Cardiotocography (CTG) is a standard tool for the assessment of fetal well-being during pregnancy and delivery. However, its interpretation is associated with high inter- and intra-observer variability. Since its introduction there have been numerous attempts to develop computerized systems assisting the evaluation of the CTG recording. Nevertheless these systems are still hardly used in a delivery ward. Two main approaches to computerized evaluation are encountered in the literature; the first one emulates existing guidelines, while the second one is more of a data-driven approach using signal processing and computational methods. The latter employs preprocessing, feature extraction/selection and a classifier that discriminates between two or more classes/conditions. These classes are often formed using the umbilical cord artery pH value measured after delivery. In this work an approach to Fetal Heart Rate (FHR) classification using pH is presented that could serve as a benchmark for reporting results on the unique open-access CTU-UHB CTG database, the largest and the only freely available database of this kind. The overall results using a very small number of features and a Least Squares Support Vector Machine (LS-SVM) classifier, are in accordance to the ones encountered in the literature and outperform the results of a baseline classification scheme proving the utility of using advanced data processing methods. Therefore the achieved results can be used as a benchmark for future research involving more informative features and/or better classification algorithms.

Human Placental Arterial Distensibility, Birth Weight, and Body Size Are Positively Related to Fetal Homocysteine Concentration.

Methionine demethylation during metabolism generates homocysteine (Hcy) and its remethylation requires folate and cobalamin. Elevated Hcy concentrations are associated with vascular-related complications of pregnancy, including increased vascular stiffness, predictive of clinical vascular disease. Maternal and fetal total Hcy (tHcy) concentrations are positively related, yet the influence of Hcy on fetoplacental vascular function in normal pregnancy has not been examined. We hypothesized that Hcy alters fetoplacental vascular characteristics with influences on fetal growth outcomes. We investigated (1) placental chorionic plate artery distensibility and neonatal blood pressure in relation to umbilical plasma tHcy; (2) relationships between cord venous (CV) and cord arterial (CA) plasma tHcy, folate, and cobalamin concentrations; and (3) tHcy associations with birth weight and anthropometric measurements of body size as indices of fetal growth in normal pregnancies with appropriate weight-for-gestational age newborns. Maternal plasma tHcy, folate, and cobalamin concentrations were consistent with published data. Placental chorionic plate artery distensibility index (β; measure of vessel stiffness) was inversely related to CA tHcy, yet neonatal blood pressure was not significantly affected. CV and CA tHcy concentrations were positively related and CV tHcy negatively related to CV cobalamin but not folate. CV tHcy concentration positively related to birth weight, corrected birth weight percentile, length, head circumference, and mid-arm circumference of newborns. CV cobalamin was inversely related to fetal growth indices but not to folate concentration. Our study demonstrates a potential relationship between fetal tHcy and placental artery distensibility, placing clinical relevance to cobalamin in influencing Hcy concentration and maintaining low vascular resistance to facilitate nutrient exchange favorable to fetal growth.

Surgical roadmap for congenital cervical spine abnormalities

Study Design A descriptive study based on medical records of patients with congenital cervical spine abnormalities. Objective The hypothesis of the study was that patients with congenital cervical spine abnormalities could be divided according to the main pathological syndrome. Summary of Background Data Abnormalities of the cervical spine belong to embryopathies and are a very heterogeneous group. The variety of this pathology made it hard to create a general classification based on a morphological approach. Materials Medical records of 68 patients with congenital cervical spine abnormalities were analyzed and were a clinical material for working out the algorithm of their management. Computer tomography, magnetic resonance imaging (MRI) and selective angiography were used to specify the abnormality structure and preoperative planning. Use of functional positioning was an important feature in all these investigations. Various techniques of surgical treatment such as halo, anterior and posterior fusion, decompression of the cerebral, spinal cord and cervical vertebral arteries, revision of the spinal canal, neurolysis, and meningolysis were used in 28 patients aged from 2 to 47 years old. Results All patients were divided according to leading pathological syndromes. Those were instability, stenosis and brain ischemia. Each group had its own important subgroup. The main surgical steps in management of complex congenital anomalies of the cervical spine were bone fusion or (and) decompression of the brain and spinal cord. Conclusions Selection of the main pathological syndrome or combination of syndromes is a simple and effective way for making the right decision when treating patients with congenital cervical spine abnormalities. Syndromic approach can be used for prognosis as well.

The effect of type and volume of fluid hydration on labor duration of nulliparous women: a randomized controlled trial

Type and volume of fluid administered for intrapartum maintenance had been reported to differently affect labor length, delivery mode, and cord artery pH and glucose level. We aimed to compare the effect of three different fluid regimens on labor duration. In a randomized trial, healthy nulliparous in labor were randomized into one of three intravenous fluid regimens: group 1, the reference group, lactated Ringer's solution infused at a rate of 125mL/h; group 2, lactated Ringer's solution infused at a rate of 250mL/h; group 3, 0.9% saline solution boosted with 5% glucose, infused at a rate of 125mL/h. The primary outcome was labor length from enrollment until delivery. Between December 2010 and July 2015, 300 women were randomized to one of the three groups. Demographic and baseline obstetric characteristics were comparable between the groups. There was no significant difference in the time from enrollment to delivery (p=0.62). Furthermore, there were no significant differences in second stage duration (p=0.73), mode of delivery (p=0.21), cord artery pH and glucose level between the groups. Increasing the intravenous volume of lactated Ringer's solution or substituting to fluid containing 5% glucose solution does not affect labor length. ClinicalTrials.gov, http://www.clinicaltrials.gov , NCT01242293.

Umbilical cord as human cell source for mitral valve tissue engineering – venous vs. arterial cells

Around 2% of the population in developed nations are affected by mitral valve disease and available valvular replacements are not designed for the atrioventricular position. Recently our group developed the first tissue-engineered heart valve (TEHV) specifically designed for the mitral position - the TexMi valve. The valve recapitulates the main components of the native valve, i.e. annulus, asymmetric leaflets and the crucial chordae tendineae. In the present study, we evaluated the human umbilical cord as a clinically applicable cell source for the TexMi valve. Valves produced with cells isolated from human umbilical cord veins (HUVs) and human umbilical cord arteries (HUAs) were conditioned for 21 days in custom-made bioreactors and evaluated in terms of extracellular matrix (ECM) composition and mechanical properties. In addition, static cell-laden fibrin discs were molded to investigate cell-mediated tissue contraction and differences in ECM production. HUA and HUV cells were able to deliver functional valves with a rich ECM composed mainly of collagen. Particularly noteworthy was the synthesis of elastin, which has been observed rarely in TEHV. The elastin synthesis was significantly higher in TexMi valves produced with HUV cells and therefore the HUV is considered to be the preferred cell source.

ДОПЛЕРОМЕТРИЧНЕ ДОСЛІДЖЕННЯ МАТКОВО-ПЛАЦЕНТАРНО-ПЛОДОВОГО КРОВОПЛИНУ У ВАГІТНИХ З ПЕРВИННОЮ АРТЕРІАЛЬНОЮ ГІПОТОНІЄЮ

Мета дослідження – вивчення гемодинамічних процесів у системі мати – плацента – плід у вагітних з первинною артеріальною гіпотонією.Матеріали та методи. Проведено доплерометричне дослідження матково-плацентарного та плодово-плацентарного кровоплину у 43 вагітних із первинною артеріальною гіпотонією та 32 здорових вагітних з нормальним артеріальним тиском у терміни гестації – 20–24 тиж., 28–32 тиж., 37–41 тиж. Для оцінки стану гемодинаміки в системі мати – плацента – плід проводилось доплерометричне дослідження кровоплину з допомогою приладу «SA-8000 EX» (Medison, Південна Корея) в акушерських програмах конвексним датчиком (3,5 МГц). Доплерометричне дослідження включало оцінку кровотоку в маткових артеріях, артеріях пуповини та середній мозковій артерії плода.Результати дослідження та їх обговорення. Виявлено закономірності становлення гемодинамічних процесів у системі мати – плацента – плід у двох групах спостереження. У групі вагітних з первинною артеріальною гіпотонією індекси судинного опору в правій і лівій маткових артеріях були достовірно вищими, ніж у контрольній групі, з переважанням змін у правій матковій артерії. Гемодинамічні прояви при первинній артеріальній гіпотонії з боку матково-плацентарного контуру виглядали при ультразвуковому дослідженні як розширення інтервільозного простору, збільшення поперечного розміру крайового синуса, варикозне розширення параметральних вен. Явища венозного застою у матково-плацентарному контурі супроводжувались вищими показниками індексів судинного опору у маткових артеріях і частіше при динамічному спостереженні призводили до розвитку затримки росту плода. Вивчення гемодинамічних показників в артерії пуповини виявило тенденцію до зростання всіх індексів упродовж вагітності у І групі та зменшення – у ІІ групі; при цьому у вагітних з первинною артеріальною гіпотонією в ІІІ триместрі спостерігалось достовірне збільшення показників порівняно з контрольною групою. Вивчення плодової гемодинаміки виявило зниження резистентності кровоплину в середній мозковій артерії плода із прогресуванням вагітності та розвитком централізації кровообігу. Посилення мозкового кровообігу плода є компенсаторною реакцією на хронічну тканинну гіпоксію.Висновки. Порушення матково-плацентарного кровоплину, які розвиваються у вагітних з первинною артеріальною гіпотонією, починаючи з ІІ триместру вагітності, в подальшому призводять до фетального дистресу.

Role of 3D printing positioning guide template in pedicle screw fixation of unstable atlas fractures

Objective To investigate the clinical outcomes of pedicle screw fixation assisted with the 3D printing positioning guide template for treatment of unstable atlas fractures. Methods A retrospective case series review was made on 10 patients with unstable atlas fractures undergone direct posterior C1 pedicle screw fixation assisted with the 3D printing drill guide template from September 2012 to May 2015. There were 7 males and 3 females, with a mean age of 52.6 years (range, 23-75 years). All patients complained of neck pain, stiffness and decreased range of motion without neurologic deficit. Preoperative skull traction was used routinely. After the three-dimension reconstruction of cervical vertebrae, ideal trajectory for C1 pedicle screws was designed with a complementary basal template for posterior surface of atlas corresponding anatomical structure. Then the drill guide template was materialized in a rapid prototyping machine and used during operation. Start point and direction of the ideal and actual trajectories were measured after matching the position of the pre- and post-operative patients’ cervical spine. Safety of pedicle screw fixation was assessed in the transverse and sagittal planes of CT scan. Operation time and blood loss were recorded. Visual Analogue Scale (VAS) of neck pain was recorded before operation and 3 months after operation. Clinical efficacy, fracture reduction, stability and surgical complications were reviewed at the follow-up. Results A total of 20 screws were inserted safely. No significant differences existed in deviation of entry point and direction between ideal and actual trajectories (P>0.05). Operation time was 60-90 min (mean, 75 min) and intraoperative blood loss was 110-300 ml (mean, 160 ml). No spinal cord or vertebral artery injury was noted during operation. All patients were followed up for 12-36 months (mean, 20.5 months). VAS was improved from preoperative 7.3(6.3-9.5)points to 1.4(0.3-2.5) points 3 months after operation (P<0.05). All patients had normal range of motion of the cervical spine 3 months after operation. Bony fusion was achieved 6 months after operation. At the follow-up, good cervical alignment was maintained with no instrument failure and C1-2 instability. Conclusion For treatment of unstable atlas fractures, direct posterior C1 pedicle screw fixation assisted with the 3D printing drill guide template can improve the precision of screw placement, reduce complications, and preserve the function of the occipital-atlanto-axial junction. Key words: Atlas; Fracture fixation, internal; Rapid prototyping

Placental characteristics in monochorionic twins with selective intrauterine growth restriction assessed by gradient angiography and three-dimensional reconstruction

Objective: To investigate the placental characteristics in selective intrauterine growth restriction (sIUGR) using gradient angiography and three-dimensional (3D) reconstruction from computed tomography (CT) scan data.Methods: This study included 23 sIUGR cases and 16 monochorionic twin-pregnancies without sIUGR. We injected nonionic iodinated contrast agents into the umbilical arteries and veins. Placental characteristics were analyzed after CT scanning and 3D reconstruction.Results: 73.9% of smaller twins in sIUGR cases had marginal or velamentous cord insertions and less placental sharing. The terminal branch of the arterial tree was scored III–IV in smaller sIUGR twins, while it was scored V–VII in normal monochorionic twins and larger sIUGR twins. Arterio-arterial (A-A) anastomoses presented in all monochorionic placentas. Veno-venous (V-V) anastomoses present in 83.3% (5/6) of Type III sIUGR cases, which was higher than observed in Type I–II cases. The mean diameters of A-A and V-V anastomoses were larger in Type III sIUGR cases.Conclusions: Gradient angiography and 3D placental models displayed different placental angioarchitectures and voluminal placental sharing among three types of sIUGR cases. Placental dysplasia in the smaller twin may cause abnormal cord insertion and unequal placental sharing. The inter-twin anatomoses influence the umbilical cord artery (UA) Doppler and natural pathogenesis of sIUGR.

Intrauterine growth trajectories modify the epigenetic programming of vascular-related genes in human umbilical artery endothelium and cord adiponectin levels

Intrauterine growth trajectories modify the epigenetic programming of vascular-related genes in human umbilical artery endothelium and cord adiponectin levels

The effect of maternal low flow oxygen administration during the second stage of labour on umbilical cord artery pH: a randomised controlled trial.

To assess the effect of maternal low flow oxygen administration during the second stage of labour on umbilical cord artery pH. A randomised controlled trial. A tertiary teaching hospital in China. Women in the second stage of labour with no complications. About 443 women were randomly allocated to receive either supplemental oxygen at a flow rate of 2l/min or a sham supplementation by nasal cannula. Healthcare providers, women and outcome assessors were blinded to allocation. Umbilical cord artery pH and fetal heart rate (FHR) pattern. Baseline characteristics were similar between the two groups. There were no significant differences between the two groups in the umbilical cord artery pH [median 7.261, interquartile range (IQR) 7.228-7.295 versus 7.266 (IQR 7.232-7.297), P=0.64], the proportion with pH less than 7.2 [30/219 versus 34/224, P=0.66, RR (relative risk) 0.9, 95% CI 0.57-1.42], and the proportion with normal FHR pattern (147/219 versus 153/224, P=0.79, RR 0.98, 95% CI 0.86-1.12). Maternal partial pressure of dissolved oxygen was significantly higher in the oxygen group than in the sham group [median 150.0mmHg (IQR 142.6-156.7) versus 112.0 (IQR 104.8-118.3), P<0.001], whereas carbon dioxide was significantly lower in the oxygen group than in the sham group (mean difference -1.1, 95% CI -2.1 to -0.1, P=0.03). The use of 2l/min maternal oxygen during the second stage of labour did not adversely affect either the umbilical artery pH or the FHR pattern distribution. No difference in abnormal fetal acid base or normal heart rate if maternal O2 given, randomised trial finds.

Individualized 3D printing navigation template for pedicle screw fixation in upper cervical spine.

PurposePedicle screw fixation in the upper cervical spine is a difficult and high-risk procedure. The screw is difficult to place rapidly and accurately, and can lead to serious injury of spinal cord or vertebral artery. The aim of this study was to design an individualized 3D printing navigation template for pedicle screw fixation in the upper cervical spine.MethodsUsing CT thin slices data, we employed computer software to design the navigation template for pedicle screw fixation in the upper cervical spine (atlas and axis). The upper cervical spine models and navigation templates were produced by 3D printer with equal proportion, two sets for each case. In one set (Test group), pedicle screws fixation were guided by the navigation template; in the second set (Control group), the screws were fixed under fluoroscopy. According to the degree of pedicle cortex perforation and whether the screw needed to be refitted, the fixation effects were divided into 3 types: Type I, screw is fully located within the vertebral pedicle; Type II, degree of pedicle cortex perforation is <1 mm, but with good internal fixation stability and no need to renovate; Type III, degree of pedicle cortex perforation is >1 mm or with the poor internal fixation stability and in need of renovation. Type I and Type II were acceptable placements; Type III placements were unacceptable.ResultsA total of 19 upper cervical spine and 19 navigation templates were printed, and 37 pedicle screws were fixed in each group. Type I screw-placements in the test group totaled 32; Type II totaled 3; and Type III totaled 2; with an acceptable rate of 94.60%. Type I screw placements in the control group totaled 23; Type II totaled 3; and Type III totaled 11, with an acceptable rate of 70.27%. The acceptability rate in test group was higher than the rate in control group. The operation time and fluoroscopic frequency for each screw were decreased, compared with control group.ConclusionThe individualized 3D printing navigation template for pedicle screw fixation is easy and safe, with a high success rate in the upper cervical spine surgery.