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

Development and validation of a model to predict mortality risk among extremely preterm infants during the early postnatal period: a multicentre prospective cohort study

BACKGROUND

Recently, with the rapid development of the perinatal medical system and related life-saving techniques, both the short-term and long-term prognoses of extremely preterm infants (EPIs) have improved significantly. In rapidly industrialising countries like China, the survival rates of EPIs have notably increased due to the swift socioeconomic development. However, there is still a reasonably lower positive response towards the treatment of EPIs than we expected, and the current situation of withdrawing care is an urgent task for perinatal medical practitioners.

OBJECTIVE

To develop and validate a model that is practicable for EPIs as soon as possible after birth by regression analysis, to assess the risk of mortality and chance of survival.

METHODS

This multicentre prospective cohort study used datasets from the Sino-Northern Neonatal Network, including 46 neonatal intensive care units (NICUs). Risk factors including maternal and neonatal variables were collected within 1 hour post-childbirth. The training set consisted of data from 41 NICUs located within the Shandong Province of China, while the validation set included data from 5 NICUs outside Shandong Province. A total of 1363 neonates were included in the study.

RESULTS

Gestational age, birth weight, pH and lactic acid in blood gas analysis within the first hour of birth, moderate-to-severe hypothermia on admission and adequate antenatal corticosteroids were influencing factors for EPIs' mortality with important predictive ability. The area under the curve values for internal validation of our prediction model and Clinical Risk Index for Babies-II scores were 0.81 and 0.76, and for external validation, 0.80 and 0.51, respectively. Moreover, the Hosmer-Lemeshow test showed that our model has a constant degree of calibration.

CONCLUSIONS

There was good predictive accuracy for mortality of EPIs based on influencing factors prenatally and within 1 hour after delivery. Predicting the risk of mortality of EPIs as soon as possible after birth can effectively guide parents to be proactive in treating more EPIs with life-saving value.

TRIAL REGISTRATION NUMBER

ChiCTR1900025234.

Do Delivery Mode and Anesthesia Management Alter Redox Setting in Neonates?

Objective Fetal-to-neonatal transition is accompanied by oxidative stress. The degree of oxidative damage may depend on several factors, such as delivery type and obstetric anesthesia type. The objective of the study was to determine if the delivery type and obstetric anesthesia type have an impact on oxidative stress levels in newborns.

Material and methods A prospective study included 150 newborns divided into three groups: neonates delivered vaginally, via cesarean section in general anesthesia, and via cesarean section in spinal anesthesia. Levels of pH, PaO2, lactate, glutathione peroxidase, and thiobarbituric acid reactive substance were quantified and compared between groups.

Results Vaginal delivery was followed by the highest lactate and thiobarbituric acid reactive substance levels and lowest pH, PaO2, and glutathione peroxidase levels. Higher values of thiobarbituric acid reactive substance, PaO2, and glutathione peroxidase and lower pH values were noted in neonates delivered in general anesthesia in comparison to neonates delivered in spinal anesthesia.

Conclusions Neonates delivered in general anesthesia were most prone to oxidative stress, while neonates delivered in spinal anesthesia were least affected by reactive oxygen species.

Umbilical Cord Blood-Derived Exosomes in Maternal-Fetal Disease: a Review

The nutrients and other factors transported by umbilical cord blood, which is vital for fetal survival, play crucial roles in fetal development. There are various communication modes between the fetal-placental system and the maternal-placental system, and these communication modes are all mediated by umbilical cord blood. During the process of umbilical cord blood transportation, the changes of some nutrients and factors may play a key role in fetal development. Exosomes, which are members of the extracellular vesicle family, are present in the umbilical cord blood and play roles in information transmission as a result of their efficient cellular communication activity. The study of umbilical cord blood-derived exosomes provides a new approach for research on the etiology of maternal-fetal diseases and they may be useful for the development of intrauterine treatments. This review summarizes specific functions and research directions regarding umbilical cord blood-derived exosomes, and their potential associations with pregnancy complications.

Comparative evaluation of normal saline, 1/3-2/3, and ringer's lactate infusion on labour outcome, PH, bilirubin, and glucose level of the umbilical cord blood in nulliparous women with labour induction: a randomised clinical trial

This study aimed to compare the effects of infusion of normal saline, 1/3-2/3, and Ringer's lactate fluids on labour outcome, pH, bilirubin, and glucose level of umbilical cord blood. In this randomised clinical trial, 450 nulliparous women with Bishop score ˂5 and indication of pregnancy termination were randomly divided into three groups to receive normal saline, 1/3-2/3, or Ringer's lactate infusion at a rate of 125 mL/h for hydration, upon starting induction of labour. Results of this study indicated that the incidence of hypoglycaemia (p = .19), hyper bilirubinemia (p = .87) and acidosis (p = .10) was similar in neonates of the three groups. Also, there were no statistically significant differences between the three groups with regard to the duration of labour; glucose, bilirubin and pH level of cord blood; and mode of delivery. It can be concluded that infusion of Ringer's lactate, normal saline or 1/3-2/3 fluid during labour is not associated with different maternal or foetal/neonatal outcomes, and none of the fluids has superiority to the others.Impact statementWhat is already known on this subject? Several studies have been conducted on the association between type and volume of infused fluid on labour duration and neonatal outcomes. However, there has been some controversy.What do the results of this study add? This is the first study that has investigated the association between infusion of Ringer's lactate, normal saline or 1/3-2/3 fluid during labour with labour outcome and pH, bilirubin, and glucose level of the umbilical cord blood and results showed that these fluids have no effect on maternal or foetal/neonatal outcomes and also none of these fluids has superiority to the others.What are the implications of these findings for clinical practice and/or further research? Due to contradictory results of previous studies, further research with greater sample sizes and different fluids type and volumes may be needed to examine the association between infusion of fluids and neonatal and labour outcomes more precisely.

Umbilical artery lactate levels and associated maternal and newborn characteristics at Mulago National Referral Hospital: a cross-sectional observational study

OBJECTIVE

To determine the maternal and newborn characteristics associated with high umbilical artery lactate levels at Mulago National Referral Hospital.

DESIGN

Cross-sectional observational study.

SETTING

Department of Obstetrics and Gynecology at a national referral hospital located in the capital of Uganda, Kampala.

PARTICIPANTS

We randomly selected 720 pregnant mothers at term who presented in labour and their newborn babies.

PRIMARY OUTCOME

Umbilical artery lactate level.

RESULTS

During the study, there were 579 vaginal deliveries (18 instrumental) and 141 caesarean sections which met the inclusion criteria. One hundred and eighty-seven neonates (187) had high arterial lactate levels. The following factors were associated with an increased likelihood of high lactate concentration: male sex (adjusted OR (aOR)=1.71; 95% CI 1.16 to 2.54; p<0.05), primigravidity (aOR=2.78; 95% CI 1.89 to 4.08; p<0.001), meconium-stained liquor (aOR=5.85; 95% CI 4.08 to 8.47; p<0.001) and administration of oxytocin (aOR=1.97; 95% CI 1.00 to 3.77; p<0.05).

CONCLUSION

About a fifth of the babies born in Mulago National Referral Hospital during the study period had high umbilical artery lactate. The maternal-fetal factors significantly associated with high umbilical artery lactate levels included: baby's sex, mother's gravidity, meconium-stained amniotic fluid and oxytocin administration during labour.

Effect of pre-operative bicarbonate infusion on maternal and perinatal outcomes among women with obstructed labour in Mbale hospital: A double blind randomized controlled trial

INTRODUCTION

Oral bicarbonate solution is known to improve both maternal and perinatal outcomes among women with abnormal labour (dystocia). Its effectiveness and safety among women with obstructed labour is not known.

OBJECTIVE

To determine the effect and safety of a single-dose preoperative infusion of sodium bicarbonate on maternal and fetal blood lactate and clinical outcomes among women with obstructed labour (OL) in Mbale hospital.

METHODS

We conducted a double blind, randomised controlled trial from July 2018 to September 2019. The participants were women with OL at term (≥37 weeks gestation), carrying a singleton pregnancy with no other obstetric emergency, medical comorbidity or laboratory derangements.

INTERVENTION

A total of 477 women with OL were randomized to receive 50ml of 8.4% sodium bicarbonate (238 women) or 50 mL of 0.9% sodium chloride (239 women). In both the intervention and controls arms, each participant was preoperatively given a single dose intravenous bolus. Every participant received 1.5 L of normal saline in one hour as part of standard preoperative care.

OUTCOME MEASURES

Our primary outcome was the mean difference in maternal venous blood lactate at one hour between the two arms. The secondary outcomes were umbilical cord blood lactate levels at birth, neonatal sepsis and early neonatal death upto 7 days postnatal, as well as the side effects of sodium bicarbonate, primary postpartum hemorrhage, maternal sepsis and mortality at 14 days postpartum.

RESULTS

The median maternal venous lactate was 6.4 (IQR 3.3-12.3) in the intervention and 7.5 (IQR 4.0-15.8) in the control group, with a statistically non-significant median difference of 1.2 mmol/L; p-value = 0.087. Vargha and Delaney effect size was 0.46 (95% CI 0.40-0.51) implying very little if any effect at all.

CONCLUSION

The 4.2g of preoperative intravenous sodium bicarbonate was safe but made little or no difference on blood lactate levels.

TRIAL REGISTRATION

PACTR201805003364421.

Neuroapoptosis in newborns with respiratory acidosis at birth

BACKGROUND

S100B protein is one of the most accurate biomarkers for diagnosis of neuroapoptosis and brain damage. The aim was to evaluate the lactate concentration and acid-base balance (pH, pCO₂, pO₂, HCO₃c and BEb) in umbilical cord blood to predict high risk of neuroapoptosis and analyze the relationship between the levels of these biomarkers and umbilical cord blood S100B protein concentration at birth.

METHODS

Apparently healthy newborns were included. S100B protein and blood gas test (lactate and acid-base balance) were determined in umbilical cord blood at birth. Newborns were classified into two groups: with and without high risk of neuroapoptosis. Newborns with high umbilical cord blood S100B protein concentration were considered newborns at high risk of neuroapoptosis.

RESULTS

Sixty-one newborns were included, 12 had high risk of neuroapoptosis and 49 did not. S100B protein concentration correlate directly with pCO₂ levels (Rho: 0.286, p = .0321) and lactate concentration (Rho: 0.278, p = .0315); and indirectly with pH (Rho: -0.332, p = .01). The analysis of the ROC curves yielded significant curves for pH and pCO₂ to predict high risk of neuroapoptosis, pH optimal cutoff value was 7.19 (sensitivity: 50%, specificity: 83.7%, AUC: 0.708); and pCO₂ optimal cutoff value was 60 mmHg (sensitivity: 30%, specificity: 85.4%, AUC: 0.705).

CONCLUSIONS

Respiratory acidosis is associated to high concentrations of S100B protein in umbilical cord blood at birth. Umbilical cord blood pH and pCO₂ may be useful in differentiating newborns at high risk of neuroapoptosis. Umbilical cord blood gas test may be valuable as risk indicator for neuroapoptosis at birth.