Pulmonary hypertension is an important co-morbidity in developmental lung diseases of infancy: Bronchopulmonary dysplasia and congenital diaphragmatic hernia

Seeing pulmonary hypertension through a paediatric lens: a viewpoint

Pulmonary hypertension (PH) is a life-threating condition associated with abnormally elevated pulmonary pressures and right heart failure. Current epidemiological data indicate that PH aetiologies are different between the adult and paediatric population. The most common forms of PH in adults are PH from left heart disease or chronic lung disease, followed by pulmonary arterial hypertension (PAH) [1]; in paediatric patients, PH is most often associated with developmental lung disorders and congenital heart disease (CHD) [2, 3]. In contrast to adults with PH, wherein patients worsen over time despite therapy, PH in children can improve with growth. For example, in infants with bronchopulmonary dysplasia (BPD) and PH morbidity and mortality are high, but with lung growth and ensuring no ongoing lung injury pulmonary vascular disease can improve as evidenced by discontinuation of vasodilator therapy in almost two-thirds of BPD-PH survivors by age 5 years [3, 4].

Paediatric pulmonary hypertension (PH) offers unique genetic and developmental insights that can help in the discovery of novel mechanisms and targets to treat adult PH https://bit.ly/3TMm6bi

Perioperative Improvement in Pulmonary Function in Infants with Congenital Diaphragmatic Hernia

OBJECTIVE

The objective of this study was to compare serial changes in pulmonary function in contemporary infants with congenital diaphragmatic hernia managed with a gentle ventilation approach.

STUDY DESIGN

Observational cohort, single-center study of infants ≥35^0/7 weeks gestation at delivery with congenital diaphragmatic hernia. Functional residual capacity (FRC), passive respiratory compliance, and passive respiratory resistance were measured presurgical and postsurgical repair and within 2 weeks of discharge. A 1-way analysis of variance for repeated measures was used to evaluate the change in FRC, passive respiratory compliance, and passive respiratory resistance over these repeated measures.

RESULTS

Twenty-eight infants were included in the analysis with a mean gestational age of 38.3 weeks and birth weight of 3139 g. We found a significant increase in FRC across the 3 time points (mean in mL/kg [SD]: 10.9 [3.6] to 18.5 [5.2] to 24.2 [4.4]; P < .0001). There was also a significant increase in passive respiratory compliance and decrease in passive respiratory resistance. In contrast to a previous report, there were survivors in the current cohort with a preoperative FRC of <9 mL/kg. The mean FRC measured at discharge was in the range considered within normal limits. Sixteen infants had prenatal measurements of the lung-to-head ratio, but there was no relationship between the lung-to-head ratio and preoperative or postoperative FRC measurements.

CONCLUSIONS

Infants with congenital diaphragmatic hernia demonstrate significant increases in FRC and improvements in respiratory mechanics measured preoperatively and postoperatively and at discharge. We speculate these improvements are due to the surgical resolution of the mechanical obstruction to lung recruitment and that after achieving preoperative stability, repair should not be delayed given these demonstrable postoperative improvements.

The value of modified Ross score in the evaluation of children with severe lower respiratory tract infection admitted to the pediatric intensive care unit

Heart failure (HF) represents an important cause of morbidity and mortality in children. It is mostly caused by congenital heart disease (CHD) and cardiomyopathy. The Ross HF classification was developed to assess severity in infants and has subsequently been modified to apply to all pediatric ages. The modified Ross classification for children provides a numeric score comparable with the New York Heart Association (NYHA) HF classification for adults. The aim of this work is to investigate the role of modified Ross score in the evaluation of children with severe lower respiratory tract infection admitted to the pediatric intensive care unit (PICU). One hundred and sixty-four children with severe LRTI admitted to the PICU were enrolled in this prospective cohort study, which was carried out at Assiut University Children Hospital, from the start of July 2021 up to the end of December 2021. Sixty patients (36.6%) of studied cases with severe LRTI admitted to PICU had HF. Out of these, 37 (61.7%) had mild HF; 17 (28.3%) had moderate HF, while six cases (10%) had severe HF according to the modified Ross score. The value of modified Ross score was significantly higher in children with heart failure with sensitivity and specificity 100% with cutoff value of 2. Admission to NICU, history of previous ventilation, and prematurity were higher in patients who developed HF. Patients with pulmonary hypertension (PH) and those with raised neutrophil lymphocyte ratio were significantly higher in the group of patients with moderate and severe degree of HF.   Conclusion: Modified Ross score is a simple clinical score which may help in assessing and predicting children with severe LRTI. What is Known: • Hear failure is common complication to lower respiratory tract infection. • Modified Ross score was used to predict and classify heart failure in adult with lower respiratory infection. What is New: • Modified Ross score found to be of value in prediction of heart failure in children with lower respiratory tract infection.

Early vasopressin infusion improves oxygenation in infants with congenital diaphragmatic hernia

Objective

Congenital Diaphragmatic Hernia (CDH) is a complex disease including a diaphragmatic defect, lung hypoplasia, and pulmonary hypertension. Despite its increasing use in neonates, the literature on the use of vasopressin in neonates is limited. The aim of this work is to analyze the changes in clinical and hemodynamic variables in a cohort of CDH infants treated with vasopressin.

Methods

Among CDH infants managed at the Neonatal Intensive Care Unit (NICU) of our hospital from May 2014 to January 2019, all infants who were treated with vasopressin, because of systemic hypotension and pulmonary hypertension, were enrolled in this retrospective study. The primary outcome was the change in oxygenation index (OI) after the start of the infusion of vasopressin. The secondary outcomes were the changes in cerebral and splanchnic fractional tissue oxygen extraction (FTOEc and FTOEs) at near-infrared spectroscopy, to understand the balance between oxygen supply and tissue oxygen consumption after the start of vasopressin infusion. We also reported as secondary outcomes the changes in ratio of arterial oxygen partial pressure (PaO2) to fraction of inspired oxygen (FiO2), heart rate, mean arterial pressure, serum pH, and serum sodium.

Results

We included 27 patients with isolated CDH who received vasopressin administration. OI dramatically dropped when vasopressin infusion started, with a significant reduction according to ANOVA for repeated measures (p = 0.003). A global significant improvement in FTOEc and FTOEs was detected (p = 0.009 and p = 0.004, respectively) as a significant reduction in heart rate (p = 0.019). A global significant improvement in PaO2/FiO2 ratio was observed (p < 0.001) and also at all time points: at 6 h since infusion (p = 0.015), 12 h (p = 0.009), and 24 h (p = 0.006), respectively. A significant reduction in sodium levels was observed as expected side effect (p = 0.012). No significant changes were observed in the remaining outcomes.

Conclusion

Our data suggest that starting early vasopressin infusion in CDH infants with pulmonary hypertension could improve oxygenation index and near-infrared spectroscopy after 12 and 24 h of infusion. These pilot data represent a background for planning future larger randomized trials to evaluate the efficacy and safety of vasopressin for the CDH population.

Building a Dedicated Pediatric Pulmonary Hypertension Program: A Consensus Statement from the Pediatric Pulmonary Hypertension Network

Pediatric pulmonary hypertension (PH) is a severe, life‐threatening disease associated with diverse cardiac, pulmonary, and systemic disorders, which generally requires expertise from multiple disciplines for management. Unfortunately, expert centers are limited, often due to inadequate resources or unfamiliarity with needed components for success. The Pediatric Pulmonary Hypertension Network (PPHNet) includes expert centers in North America specifically dedicated to advancing the field of pediatric PH through research and excellent clinical care. PPHNet member sites were queried for valuable program components and these findings were discussed for consensus. Here we provide a collective overview of key elements of an optimal pediatric PH program: team composition, access to services, and commitment to education. It is our intention that this document will assist newer and/or smaller programs identify avenues and resources for growth and provide avenues for collaboration.

Cellular Origin(s) of Congenital Diaphragmatic Hernia

Congenital diaphragmatic hernia (CDH) is a structural birth defect characterized by a diaphragmatic defect, lung hypoplasia and structural vascular defects. In spite of recent developments, the pathogenesis of CDH is still poorly understood. CDH is a complex congenital disorder with multifactorial etiology consisting of genetic, cellular and mechanical factors. This review explores the cellular origin of CDH pathogenesis in the diaphragm and lungs and describes recent developments in basic and translational CDH research.