The association between discordant umbilical arterial resistance in growth-restricted fetuses and adverse outcomes

BACKGROUND

Assessing the umbilical artery pulsatility index via Doppler measurements plays a crucial role in evaluating fetal growth impairment.

OBJECTIVE

This study aimed to investigate perinatal outcomes associated with discordant pulsatility indices of umbilical arteries in fetuses with growth restriction.

STUDY DESIGN

In this retrospective cohort study, all singleton pregnancies were included if their estimated fetal weight and/or abdominal circumference fell below the 10th percentile for gestational age (2017-2022). Eligible cases included singleton pregnancies with concurrent sampling of both umbilical arteries within 14 days of birth at the ultrasound evaluation closest to delivery. The exclusion criteria included births before 22 weeks of gestation, evidence of absent or reverse end-diastolic flow in either umbilical artery, and known fetal genetic or structural anomalies. The study compared cases with discordant umbilical artery pulsatility index values (defined as 1 umbilical artery pulsatility index at ≤95th percentile and the other umbilical artery pulsatility index at >95th percentile for gestational age) to pregnancies where both umbilical artery pulsatility indices had normal pulsatility index values and those with both umbilical arteries displaying abnormal pulsatility index values. The primary outcome assessed was the occurrence of composite adverse neonatal outcomes. Multivariable logistic regressions were performed, adjusting for relevant covariates.

RESULTS

The study encompassed 1014 patients, including 194 patients (19.1%) with discordant umbilical artery pulsatility index values among those who had both umbilical arteries sampled close to delivery, 671 patients (66.2%) with both umbilical arteries having normal pulsatility index values, and 149 patients (14.7%) with both umbilical arteries exhibiting abnormal values. Pregnancies with discordant umbilical artery pulsatility index values displayed compromised sonographic parameters compared with those with both umbilical arteries showing normal pulsatility index values. Similarly, the number of abnormal umbilical artery pulsatility index values was associated with adverse perinatal outcomes in a dose-response manner. Cases with 1 abnormal (discordant) umbilical artery pulsatility index value showed favorable sonographic parameters and perinatal outcomes compared with cases with both abnormal umbilical artery pulsatility index values, and cases with both abnormal umbilical artery pulsatility index values showed worse sonographic parameters and perinatal outcomes compared with cases with discordant UA PI values. Multivariate analysis revealed that discordant umbilical artery pulsatility indices were significantly and independently associated with composite adverse perinatal outcomes, with an adjusted odds ratio of 1.75 (95% confidence interval, 1.24-2.47; P = .002).

CONCLUSION

Evaluating the resistance indices of both umbilical arteries may provide useful data and assist in assessing adverse perinatal outcomes among fetuses with growth restriction.

Pre- and Postnatal Characterization of Autosomal Recessive KIDINS220-Associated Ventriculomegaly

Introduction

Heterozygous loss-of-function variants in the last 2 exons of KIDINS220 have been associated with spastic paraplegia, intellectual disability, nystagmus, and obesity (SINO). Syndromic features of this condition include macrocephaly and dilatation of the lateral ventricles. Homozygous variants in the more proximal exons of KIDINS220 have been reported in several fetuses with a similar but more severe phenotype of limb contractures and severe ventriculomegaly identified in the second trimester of pregnancy.

Case Presentation

We present here a 2.5-year-old female with profound global developmental delays and spasticity who was found by fetal ultrasound in week 19 of gestation to have bilateral talipes equinovarus and severe bilateral ventriculomegaly. Postnatal genetic testing revealed biallelic variants in KIDINS220.

Discussion

To our knowledge, this is the first living individual reported with the autosomal recessive form of a KIDINS220-associated condition. This case provides additional information about the postnatal phenotype and a detailed history of development from prenatal ultrasonography.

Twin pregnancy with metastatic complete molar pregnancy and coexisting live fetus

We present a case of a 34-year old G1P0 female with twin-gestation and positive prenatal screening. Initial ultrasounds demonstrated a normal live fetus with an indeterminate but persistent placental lesion. The patient presented at 23 weeks of gestational age with vaginal bleeding. On examination, a 2 cm vaginal lesion was identified. Further cross-sectional imaging demonstrated a normal appearing fetus with a mixed solid and cystic placental lesion as well as an additional lesion in the vagina. Metastatic workup revealed diffuse pulmonary metastases. Intravascular embolization was carried out to minimize the bleeding from the vaginal lesion, followed by the delivery of the fetus with an urgent Caesarean section and treatment with chemotherapy. Pathology and genetics testing confirmed diagnosis of a complete molar pregnancy with a coexisting live fetus. This case highlights the importance of any unexpected findings within the placenta or the uterus in a pregnant patient. The radiologist should maintain a high index of suspicion for gestational trophoblastic disease in such cases, communicate clearly with the clinical team and suggest appropriate additional imaging.

Postnatal dilatation of umbilical cord vessels and its impact on wall integrity: Prerequisite for the artificial placenta

INTRODUCTION

A lung assist device, which acts as an artificial placenta, can provide additional gas exchange for preterm and term newborns with respiratory failure. The concept of the lung assist device requires a large bore access via umbilical vessels to allow pumpless extracorporeal blood flow rates up to 30 mL/kg/min. After birth, constricted umbilical vessels need to be reopened for vascular access. The objective is to study the impact of umbilical vessel expansion on vessel integrity for achieving large bore access.

METHODS

Umbilical cords from healthy term deliveries were cannulated and dilatated with percutaneous transluminal angioplasty catheters in 1 mm increments from 4 to 8 mm for umbilical artery and from 4 to 15 mm for umbilical vein, n = 6 per expansion diameter. Paraffin-embedded transverse sections of dilated and control samples were HE & Van Gieson stained. Effects of dilatation, shown by splitting, were measured.

RESULTS

Umbilical vessel expansion led to concentric splitting, shown by areas devoid of extracellular matrix and nuclei in the tunica intima and media. No radial splitting was observed. Results suggest an expansion threshold of umbilical artery at 6 mm and umbilical vein at 7 mm, while maximal splitting was observed above this threshold (3.6 ± 0.8%, p = 0.043 for umbilical artery 7 mm and 6.3 ± 1.8%, p = 0.048 for umbilical vein 8 mm). Endothelial cell sloughing was present in all dilated samples but not in the control samples.

CONCLUSION

The suggested thresholds for safe expansions are similar to in utero umbilical vessel diameters and demonstrate a proof of concept for attaining large bore access for the lung assist device.

LPS from bovine serum albumin drives TNF-α release during ex-vivo placenta perfusion experiments, contaminates the perfusion system but can be effectively removed by oxidative cleaning

INTRODUCTION

The dual ex-vivo perfusion of human placental tissue is useful to study inflammatory pathways. We found significant TNF-α release in negative controls similar in concentration to lipopolysaccharide (LPS) stimulated placentas. The aim of the current study was to (i) identify sources driving TNF-α release and (ii) develop an approach to control for it.

METHOD

(i) To determine sources leading to TNF-α release, solutions frequently circulated through the perfusion system and perfusion media with different bovine serum albumin (BSA) quality were exposed to mouse macrophage cell lines (RAW264.7) and subsequently measured for TNF-α expression. (ii) To assess memory effects and validate cleaning procedures, sham perfusion experiments were conducted either in the presence or absence of exogenous LPS, in new tubing that was contaminated, cleaned and analyzed for the effectiveness of LPS removal. Oxidative and acid-base cleaning were tested for their effectiveness to reduce LPS contamination.

RESULTS

TNF-α release, observed in negative control experiments, was attributed to the use of LPS-contaminated BSA as well as inadequate cleaning of the perfusion system. Once introduced in the perfusion system, LPS accumulated and created a memory effect. Oxidative but not acid-base depyrogenation effectively reduced LPS levels to concentrations that were in accordance with FDA guidelines (<0.5 EU/mL) for medical equipment redeemed appropriate for re-use.

DISCUSSION

LPS contamination of the placenta perfusion model could have confounding effects on experimental outcomes leading to misinterpretation of data. To circumvent LPS contamination LPS-free BSA and oxidative depyrogenation cleaning techniques should be implemented in future placental perfusion studies.