Factors relating caesarean section to persistent pulmonary hypertension of the newborn

Risk of Asthma and Allergies in Children Delivered by Cesarean Section: A Comprehensive Systematic Review

BACKGROUND

It is unclear whether cesarean delivery increases the risk of allergic diseases in offspring.

OBJECTIVE

To investigate the association between cesarean delivery and the risk of allergic diseases in offspring.

METHODS

We searched PubMed, Embase, and the Cochrane Library for relevant studies up to October 12, 2023. Observational studies comparing the risk of allergic diseases in offspring delivered by cesarean section versus those delivered vaginally were included. Most-adjusted estimates from individual studies were synthesized by meta-analysis.

RESULTS

A total of 113 studies were included, 70 of which had a low risk of bias. Compared with offspring delivered vaginally, offspring delivered by cesarean section had significantly greater risks of asthma (odds ratio [OR] = 1.20; 95% CI, 1.16-1.25), allergic rhinitis or conjunctivitis (OR = 1.15' CI 1.09-1.22), atopic dermatitis or eczema (OR = 1.08; CI, 1.04-1.13), food allergies (OR = 1.35; CI, 1.18-1.54), and allergic sensitization (OR = 1.19; CI, 1.10-1.28). Cesarean delivery did not significantly increase urticaria risk. Sensitivity analyses including only studies with a low risk of bias, adjusted estimates, prospective data collection, large sample sizes, or outcomes from medical records generally supported these findings. Offspring age, study region latitude, economy type, and cesarean delivery rate accounted for some of the clinical heterogeneity. We found no data on allergic purpura.

CONCLUSIONS

Most-adjusted estimates suggest that cesarean delivery is associated with increased risks of asthma, allergic rhinitis or conjunctivitis, atopic dermatitis or eczema, food allergies, and allergic sensitization in offspring. The impact of cesarean delivery on urticaria and purpura remains uncertain.

Increased airway liquid volumes at birth impairs cardiorespiratory function in preterm and near-term lambs

Respiratory distress is relatively common in infants born at or near-term, particularly in infants delivered following elective cesarean section. The pathophysiology underlying respiratory distress at term has largely been explained by a failure to clear airway liquid, but recent physiological evidence has indicated that it results from elevated airway liquid at the onset of air-breathing. We have investigated the effect of elevated airway liquid volumes at birth on cardiorespiratory function in preterm and near-term lambs. Preterm (130 ± 0 days gestation, term ~147 days gestation; n=13) and near-term (139 ± 1 days gestation; n=13) lambs were instrumented (to measure blood pressure, blood flow and blood gas status) and at delivery airway liquid volumes were adjusted to mimic levels expected following vaginal delivery (Controls; ~7mL/kg) or elective caesarean section with no labour (elevated liquid; EL; 37mL/kg). Lambs were delivered, mechanically ventilated and monitored for blood gas status, oxygenation, ventilator requirements, blood flows (carotid artery and pulmonary artery) and blood pressure during the first few hours of life. Preterm and near-term EL lambs had poorer gas exchange and required greater ventilatory support to maintain adequate oxygenation. Pulmonary blood flow was reduced and carotid artery blood flow, mean arterial blood pressure and heart rate were reduced in EL near-term but not preterm lambs. These data provide further evidence that greater airway liquid volumes at birth adversely effects newborn cardiorespiratory function, with the effects being greater in near-term newborns.

Risk Factors and Outcomes of Acute Kidney Injury in Neonates with Persistent Pulmonary Hypertension of the Newborn

Objective

To identify the incidence of and risk factors for acute kidney injury (AKI) in neonates with persistent pulmonary hypertension of the newborn (PPHN) and to evaluate its association with neonatal outcomes.

Method

A total of 78 newborns with confirmed PPHN admitted to the neonatal intensive care unit of a university hospital between 2016 and 2020 were retrospectively analyzed. AKI was defined according to the modified neonatal Kidney Disease: Improving Global Outcomes criteria.

Results

Of 78 PPHN infants, AKI was found in 29.5% (23/78). Multivariate analysis indicated that male sex (OR 3.43 95% CI 1.03-11.48, p=0.04) and severe PPHN (OR 5.67 95% CI 1.55-20.68, p<0.01) were independently associated with increased risk for AKI. Infants with AKI had significantly higher mortality rate than infants without AKI (43.5% vs. 9.1%, p<0.01). Mortality rates in stage 1, stage 2 and stage 3 AKI were similar (36.4%, 57.1%, and 40%, respectively, p=0.68). Among survivors, AKI infants had significantly longer mechanical ventilation and lenght of stay than infants without AKI.

Conclusion

In infants with PPHN, AKI is a common complication and is associated with increased mortality, and longer mechanical ventilation and lenght of stay. Careful monitoring of kidney function in infants with PPHN, especially in males and those who had severe PPHN can help to improve patient outcomes.

Risk factors for respiratory assistance in premature infants

Premature infants are prone to dyspnea after birth due to immature development, and some infants require respiratory assistance. However, the risk factors for respiratory assistance in premature infants are rarely reported. The present study enrolled 3,394 premature infants (665 infants had been provided with respiratory assistance and 2,729 had not used respiratory assistance) to retrospectively analyze the risk factors associated with respiratory aid. The multivariate logistic regression analysis demonstrated that placental abnormality [odds ratio (OR)=1.284; P=0.048], the male sex (OR=0.696; P=0.001), delivery via cesarean section (OR=1.538; P<0.001), low 1-min Apgar score (OR=0.727; P<0.001), low birth weight (OR=0.999; P=0.005) and low gestational age (OR=0.616; P<0.001) were independent risk factors for respiratory assistance in premature infants. Overall, a number of risk factors, including placental abnormality, cesarean section, low 1-min Apgar score, low birth weight and small gestational age, were identified for respiratory assistance in premature infants. By conducting a risk assessment of risk factors at birth and using this information to provide timely respiratory assistance, the survival rates of premature infants may increase.

Characterizing dynamics of serum creatinine and creatinine clearance in extremely low birth weight neonates during the first 6 weeks of life

BACKGROUND

Characterizing the dynamics of serum creatinine concentrations (Scr) and associated creatinine clearance (CLcr) as a measure of kidney function in extremely low birth weight (≤ 1000 g; ELBW) neonates remains challenging.

METHODS

We performed a retrospective study that included longitudinal Scr (enzymatic assay) data from 148 ELBW neonates up to 6 weeks after birth. Change of Scr and inter-individual variability was characterized with nonlinear mixed-effect modeling. Key covariates such as gestational age (GA), mode of delivery (MOD), and treatment with ibuprofen or inotropic agents were investigated.

RESULTS

A total of 2814 Scr concentrations were analyzed. GA was associated with Scr at birth (higher with advancing GA), and GA and MOD showed an association with postnatal maturation of CLcr (faster clearance increase with advancing GA and after C-section). Small CLcr decrease (≤ 5%) was quantified during ibuprofen treatment. For a GA of 27 weeks, mean Scr (estimated CLcr) at birth was 0.61 mg/dl (0.23 ml/min), increasing to 0.87 mg/dl (0.27 ml/min) at day three, and decreasing to 0.36 mg/dl (0.67 ml/min) at day 42 after birth.

CONCLUSIONS

We report the first mathematical model able to characterize Scr and CLcr in ELBW neonates during the first 6 weeks of life in a quantitative manner as a function of GA, MOD, and ibuprofen treatment. This model allows the derivation of GA-adjusted reference ranges for ELBW neonates and provides a rationale for normative Scr concentrations, and as such will help clinicians to further optimize monitoring and treatment decisions in this vulnerable patient population.

Pulmonary arterial pressure in at-term in vitro fertilization neonates: A cross-sectional study

Objective:

Hormones consumption in women who conceive through in vitro fertilization (IVF) as well as embryonic manipulations have raised concerns regarding the neonates’ health, including the possibility of pulmonary hypertension. This study, therefore, aimed to assess the pulmonary arterial pressure in at-term IVF neonates.

Materials and Methods:

This prospective cross-sectional study was conducted between March 2013 and October 2017 and compares 160 IVF neonates (group 1) with 160 naturally conceived neonates (group 2). The neonates in both groups were cesarean newborns, matched in terms of gestational and neonatal age. The neonates were three-seven days old, had a full-term gestational age of 37-39 weeks and 6 days, and a normal birth weight of 2500-4000 gr. The systolic pulmonary artery pressure (SPAP) was estimated using real-time echocardiography on the basis of peak flow velocity of tricuspid regurgitation jet.

Results:

A significant difference was observed in the mean SPAPs between the two groups (p<0.001). Although, the effect of gestational age on reducing SPAP was greater and statistically significant in group 1, the gradual decrease in the PAP after birth appeared to be slower in this group. Moreover, in both groups, the effect of gestational age on reducing SPAP was more convincing than that of the neonatal age. Further, in both groups, a significant reverse correlation was observed between the SPAP and the neonatal weight; however, it appeared to be markedly higher in group 1.

Conclusion:

Our study renders IVF as being culpable in the incidence of pulmonary hypertension among neonates. Hence, to detect the likelihood of pulmonary arterial hypertension in IVF neonates, it is recommended to monitor their PAP during the neonatal period, and thereby facilitate them with the required treatment.

Can sonographic assessment of pulmonary vascular reactivity following maternal hyperoxygenation predict neonatal pulmonary hypertension? (HOTPOT study protocol)

Background

Persistent pulmonary hypertension of the newborn (PPHN) is a condition that occurs in 0.5–7 per 1000 live births and can result in significant cardiovascular instability in the newborn. It occurs when there is a failure of the normal circulatory transition in the early newborn period. Recent studies have shown that fetal pulmonary vasculature reacts to maternal hyperoxygenation (MH). The aim of the study is to assess if the in-utero response to MH can predict pulmonary hypertension in the early newborn period.

Methods

We will perform a prospective cohort study. It will evaluate the use of fetal echocardiographic Doppler assessment of the pulmonary vasculature prior to and following MH to predict fetuses that may develop pulmonary hypertension in the neonatal period. The study will be undertaken in the Rotunda Hospital, Dublin, Ireland. A fetal ultrasound and echocardiography will be performed on fetuses in the third trimester. Blood flow velocity waveforms will be recorded during periods of fetal quiescence. Pulsatility index (PI), Resistance index (RI), Peak systolic (PSV) and end diastolic velocity (EDV), time-averaged velocity (TAV), acceleration time (AT), and ejection time (ET) will be measured within the fetal distal pulmonary artery (PA). The acceleration-to-ejection time ratio (AT: ET) will be used to assess pulmonary vascular resistance (PVR). Doppler measurements will be taken at baseline and repeated immediately following MH for 10 min (O2 100% v/v inhalational gas) at a rate of 12L/min via a partial non-rebreather mask. Doppler waveform measurements from the umbilical artery (UAD), middle cerebral artery (MCA) ductus arteriosus (DA), aortic isthmus (AoI) and ductus venosus (DV) will also be obtained. After birth, a comprehensive neonatal functional echocardiogram will be performed within the first 24 hours of life.

Discussion

This study proposes to validate methods described to date in investigating the fetal pulmonary vascular response to MH, with expansion of the study subjects to include fetuses at risk of PPHN. Evaluation of the different at-risk subgroups will be informative in relation to the fetal circulatory adaptation close to term. Prediction of neonatal pulmonary hypertension may help guide the pharmacological and neonatal ICU strategies that optimise postnatal survival.

Prenatal exposure to selective serotonin reuptake inhibitors and serotonin norepinephrine reuptake inhibitors and risk for persistent pulmonary hypertension of the newborn: a systematic review, meta-analysis, and network meta-analysis

BACKGROUND

There is a marked increase in the use of selective serotonin reuptake inhibitors and serotonin norepinephrine reuptake inhibitors in the last decade. Many newborns are likely to be exposed during pregnancy and labor.

OBJECTIVE

We aimed to evaluate the association between exposure to selective serotonin reuptake inhibitors and serotonin norepinephrine reuptake inhibitors during pregnancy and the risk for persistent pulmonary hypertension of the newborn. We sought to compare the risk for persistent pulmonary hypertension of the newborn between specific selective serotonin reuptake inhibitor agents.

STUDY DESIGN

MEDLINE, Embase, and Cochrane were searched up to July 2017. No language restrictions were applied. Search key words included: "SSRI," "SNRI," "pregnancy," "risk," "new-born," and "pulmonary hypertension." Retrospective cohort studies and case-control studies reporting the risk for persistent pulmonary hypertension of the newborn in the offspring of women exposed to selective serotonin reuptake inhibitors or serotonin norepinephrine reuptake inhibitors during pregnancy, were extracted. Two independent researchers identified relevant data. Random effects meta-analysis was used to pool results. Odds ratios were calculated with subsequent 95% confidence intervals. Network meta-analysis was conducted, incorporating direct and indirect comparisons among different selective serotonin reuptake inhibitors. The primary outcome was risk for persistent pulmonary hypertension of the newborn after exposure to selective serotonin reuptake inhibitors or serotonin norepinephrine reuptake inhibitors during pregnancy.

RESULTS

A total of 11 studies were identified. A total of 156,978 women and their offspring were exposed to selective serotonin reuptake inhibitors or serotonin norepinephrine reuptake inhibitors during pregnancy. Persistent pulmonary hypertension of the newborn was detected among 452 exposed offspring, representing an incidence rate of 2.9 cases per 1000 live births and a number needed to harm of 1000. The risk for persistent pulmonary hypertension of the newborn was significantly increased in the analysis of exposure to selective serotonin reuptake inhibitor/serotonin norepinephrine reuptake inhibitor in any trimester (odds ratio, 1.82; 95% confidence interval, 1.31-2.54; I² = 72%), as well as in analysis restricted to exposure week >20 (odds ratio, 2.08; 95% confidence interval, 1.44-3.01; I² = 76%). In network meta-analysis, sertraline was ranked most likely to have the lowest risk for persistent pulmonary hypertension of the newborn among the different selective serotonin reuptake inhibitors (P = .83).

CONCLUSION

Exposure to selective serotonin reuptake inhibitors or serotonin norepinephrine reuptake inhibitors during pregnancy is associated with an increased risk for persistent pulmonary hypertension of the newborn. According to our findings, sertraline ranked as most likely to have the lowest risk for persistent pulmonary hypertension of the newborn compared to other selective serotonin reuptake inhibitors, suggesting it may have the best safety profile for use in pregnancy in this regard. Further studies are needed to fully establish these results.