The relationship between severe hypertensive diseases of pregnancy and moderate-severe bronchopulmonary dysplasia.

OBJECTIVE: Determine the association between severe hypertensive disease of pregnancy (HDP) with moderate-severe bronchopulmonary dysplasia (BPD) in preterm infants (< 31 weeks' gestation). STUDY DESIGN: Preterm birth cohort study of 693 mother-infant dyads. Severe HDP was defined as severe preeclampsia, HELLP syndrome or eclampsia. The outcome was moderate-severe BPD classified at 36 weeks corrected gestational age, per the NICHD Consensus statement. RESULTS: 225 (32%) mothers developed severe HDP and 234 (34%) infants had moderate-severe BPD. There was an interaction between severe HDP and gestational age (p = 0.03). Infants born at < 25 weeks gestation to mothers with HDP had increased odds for moderate-severe BPD compared to infants of normotensive mothers delivering at the same gestational age. Infants born > 28 weeks to mothers with severe HDP had decreased odds for the outcome, though not statistically significant. CONCLUSIONS: Severe HDP has a differential effect on the development of moderate-severe BPD based on gestational age.

Successful and Rapid Reduction in Neurosedative and Analgesic Medications in Complex Infants with Severe Bronchopulmonary Dysplasia After Tracheostomy Placement: Experience with 24-hour Propofol Infusions.

Infants with severe bronchopulmonary dysplasia may require high doses of neurosedative medications to ensure pain control and stability following tracheostomy placement. Subsequent weaning of these medications safely and rapidly is a challenge. We describe a 24-hour propofol infusion to reduce neurosedative medications in 3 high-risk infants following tracheostomy placement.

Inhaled Nitric Oxide in Neonatal Pulmonary Hypertension.

Pivotal trials investigating the use of inhaled nitric oxide (iNO) in the 1990s led to approval by the Food and Drug Administration in 1999. Inhaled nitric oxide is the only approved pulmonary vasodilator for persistent pulmonary hypertension of the newborn (PPHN). Selective pulmonary vasodilation with iNO in near-term and term neonates with PPHN is safe, and targeted use of iNO in less mature neonates with pulmonary hypertension (PH) can be beneficial. This review addresses a brief history of iNO, clinical features of neonatal PH, and the clinical application of iNO.

Muscle Flap Technique Safe for On-ECMO Congenital Diaphragmatic Hernia Repair.

INTRODUCTION: Prosthetic patches (patch) and muscle flaps (flap) are techniques used for repair of congenital diaphragmatic hernia (CDH) with a large defect unamenable to primary closure. We hypothesized that the flap technique for CDH repair while on extra-corporeal membrane oxygenation (on-ECMO) would have decreased bleeding complications compared to patch due to the hemostatic advantage of native tissue. METHODS: A single-center retrospective comparative study of patients who underwent on-ECMO CDH repair between 2008 and 2022 was performed. RESULTS: Fifty-two patients met inclusion criteria: 18 patch (34.6%) and 34 flap (65.4%). There was no difference in CDH severity between groups. On univariate analysis, reoperation for surgical bleeding was lower following flap repair compared to patch (23.5% vs 55.6%, respectively; p = 0.045), 48-h postoperative blood product transfusion was lower after flap repair (132 mL/kg vs 273.5 mL/kg patch; p = 0.006), and two-year survival was increased in the flap repair group compared to patch (53.1% vs 17.7%, respectively; p = 0.036). On multivariate analysis adjusting for CDH side, day on ECMO repaired, and day of life CDH repaired, flap repair was significantly associated with lower five-day postoperative packed red blood cell transfusion amount, improved survival to hospital discharge, and improved two-year survival. CONCLUSIONS: Our experience suggests that the muscle flap technique for on-ECMO CDH repair is associated with reduced bleeding complications compared to prosthetic patch repair, which may in part be responsible for the improved survival seen in the flap repair group. These results support the flap repair technique as a favored method for on-ECMO CDH repair. LEVEL OF EVIDENCE: Level III.

Practices and Outcomes from a Prospective, Multicenter Registry for Preterm Newborns with Pulmonary Hypertension.

OBJECTIVE: To describe current treatment practices of preterm infants with early hypoxemic respiratory failure (HRF) and pulmonary hypertension (PH) and their association with patient outcomes. STUDY DESIGN: We developed a prospective, observational, multicenter clinical registry of preterm newborns <34 weeks' gestation with HRF and PH, based on either clinical or echocardiographic evidence during the first 72 hours of life, from 28 neonatal intensive care units in the US from 2017 through 2022. The primary end point was mortality among those who did or did not receive PH-targeted treatment, and the secondary end points included comparisons of major morbidities. Variables were compared using t tests, Wilcoxon rank-sum tests, Fisher exact tests, and χ² tests. RESULTS: We analyzed the results of 224 preterm infants enrolled in the registry. Of which, 84% (188/224) received PH-targeted treatment, most commonly inhaled nitric oxide (iNO). Early mortality in this cohort was high, as 33% (71/224) of this sample died in the first month of life, and 77% of survivors (105/137) developed bronchopulmonary dysplasia. Infants who received PH-targeted treatment had higher oxygenation indices at the time of enrollment (28.16 [IQR: 13.94, 42.5] vs 15.46 [IQR: 11.94, 26.15]; P = .0064). Patient outcomes did not differ between those who did or did not receive PH-targeted therapy. CONCLUSIONS: Early-onset HRF with PH in preterm infants is associated with a high early mortality and a high risk of developing bronchopulmonary dysplasia. iNO is commonly used to treat early-onset PH in preterm infants with HRF. In comparison with untreated infants with lower oxygenation indices, iNO treatment in severe PH may prevent poorer outcomes.

Failure to Normalize Biventricular Function Is Associated with Extracorporeal Membrane Oxygenation Use in Neonates with Congenital Diaphragmatic Hernia.

We examined postnatal echocardiograms for 62 infants with congenital diaphragmatic hernia born from 2014 through 2020. Left and right ventricular dysfunction on D0 were sensitive, whereas persistent dysfunction on D2 was specific for extracorporeal membrane oxygenation requirement. Biventricular dysfunction had the strongest association with extracorporeal membrane oxygenation. Serial echocardiography may inform prognosis in congenital diaphragmatic hernia.

Hemodynamic Characterization of Neonates With Congenital Diaphragmatic Hernia-Associated Pulmonary Hypertension by Cardiac Catheterization.

We examined the results of cardiac catheterization in infants with congenital diaphragmatic hernia (CDH) from 2009 to 2020. Catheterization confirmed pulmonary arterial hypertension in all cases (n =  17) and identified left ventricular (LV) diastolic dysfunction (LVDD) in 53%. LVDD was associated with greater respiratory morbidity. Preprocedural noninvasive assessment showed inconsistent agreement with catheterization results.

Pulmonary Hypertension in Children with Down Syndrome: Results from the Pediatric Pulmonary Hypertension Network Registry.

OBJECTIVE: To characterize distinct comorbidities, outcomes, and treatment patterns in children with Down syndrome and pulmonary hypertension in a large, multicenter pediatric pulmonary hypertension registry. STUDY DESIGN: We analyzed data from the Pediatric Pulmonary Hypertension Network (PPHNet) Registry, comparing demographic and clinical characteristics of children with Down syndrome and children without Down syndrome. We examined factors associated with pulmonary hypertension resolution and a composite outcome of pulmonary hypertension severity in the cohort with Down syndrome. RESULTS: Of 1475 pediatric patients with pulmonary hypertension, 158 (11%) had Down syndrome. The median age at diagnosis of pulmonary hypertension in patients with Down syndrome was 0.49 year (IQR, 0.21-1.77 years), similar to that in patients without Down syndrome. There was no difference in rates of cardiac catheterization and prescribed pulmonary hypertension medications in children with Down syndrome and those without Down syndrome. Comorbidities in Down syndrome included congenital heart disease (95%; repaired in 68%), sleep apnea (56%), prematurity (49%), recurrent respiratory exacerbations (35%), gastroesophageal reflux (38%), and aspiration (31%). Pulmonary hypertension resolved in 43% after 3 years, associated with a diagnosis of pulmonary hypertension at age <6 months (54% vs 29%; P = .002) and a pretricuspid shunt (65% vs 38%; P = .02). Five-year transplantation-free survival was 88% (95% CI, 80%-97%). Tracheostomy (hazard ratio [HR], 3.29; 95% CI, 1.61-6.69) and reflux medication use (HR, 2.08; 95% CI, 1.11-3.90) were independently associated with a composite outcome of severe pulmonary hypertension. CONCLUSIONS: Despite high rates of cardiac and respiratory comorbidities that influence the severity of pulmonary hypertension, children with Down syndrome-associated pulmonary hypertension generally have a survival rate similar to that of children with non-Down syndrome-associated pulmonary hypertension. Resolution of pulmonary hypertension is common but reduced in children with complicated respiratory comorbidities.

High-level gonosomal mosaicism for a pathogenic non-coding CNV deletion of the lung-specific FOXF1 enhancer in an unaffected mother of an infant with ACDMPV.

BACKGROUND: Alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV) results from haploinsufficiency of the mesenchymal transcription factor FOXF1 gene. To date, only one case of an ACDMPV-causative CNV deletion inherited from a very-low level somatic mosaic mother has been reported. METHODS: Clinical, histopathological, and molecular studies, including whole genome sequencing, chromosomal microarray analysis, qPCR, and Sanger sequencing, followed by in vitro fertilization (IVF) with preimplantation genetic testing (PGT) were used to study a family with a deceased neonate with ACDMPV. RESULTS: A pathogenic CNV deletion of the lung-specific FOXF1 enhancer in the proband was found to be inherited from an unaffected mother, 36% mosaic for this deletion in her peripheral blood cells. The qPCR analyses of saliva, buccal cells, urine, nail, and hair samples revealed 19%, 18%, 15%, 19%, and 27% variant allele fraction, respectively, indicating a high recurrence risk. Grandparental studies revealed that the deletion arose on the mother's paternal chromosome 16. PGT studies revealed 44% embryos with the deletion, reflecting high-level germline mosaicism. CONCLUSION: Our data further demonstrate the importance of parental testing in ACDMPV families and reproductive usefulness of IVF with PGT in families with high-level parental gonosomal mosaicism.

Pulmonary vasodilator strategies in neonates with acute hypoxemic respiratory failure and pulmonary hypertension.

The management of acute hypoxemic respiratory failure (AHRF) in newborns continues to be a clinical challenge with elevated risk for significant morbidities and mortality, especially when accompanied with persistent pulmonary hypertension of the newborn (PPHN). PPHN is a syndrome characterized by marked hypoxemia secondary to extrapulmonary right-to-left shunting across the ductus arteriosus and/or foramen ovale with high pulmonary artery pressure and increased pulmonary vascular resistance (PVR). After optimizing respiratory support, cardiac performance and systemic hemodynamics, targeting persistent elevations in PVR with inhaled nitric oxide (iNO) therapy has improved outcomes of neonates with PPHN physiology. Despite aggressive cardiopulmonary management, a significant proportion of patients have an inadequate response to iNO therapy, prompting consideration for additional pulmonary vasodilator therapy. This article reviews the pathophysiology and management of PPHN in term newborns with AHRF while highlighting both animal and human data to inform a physiologic approach to the use of PH-targeted therapies.

Improved survival for infants with severe congenital diaphragmatic hernia.

BACKGROUND: Survival for severe (observed to expected lung-head ratio (O:E LHR) < 25%) congenital diaphragmatic hernia (CDH) remains a challenge (15-25%). Management strategies have focused on fetal endoscopic tracheal occlusion (FETO) and/or extracorporeal membrane oxygenation therapy (ECMO) utilization. OBJECTIVE(S): Describe single center outcomes for infants with severe CDH. STUDY DESIGN: Observational study of 13 severe CDH infants managed with ECMO, a protocolized DR algorithm, and early repair on ECMO with an innovative perioperative anticoagulation strategy. RESULTS: 13/140 (9.3%) infants met criteria and were managed with ECMO. 77% survived ECMO and 69% survived to discharge. 22% underwent tracheostomy. Median days on mechanical ventilation was 39 days (IQR 22:107.5) and length of stay 135 days (IQR 62.5:211.5). All infants received a gastrostomy tube (GT) and were discharged home on oxygen and pulmonary hypertension (PH) meds. CONCLUSION: Survival for infants with severe CDH can be optimized with early aggressive intervention and protocolized algorithms (149).

Cardiac Catheterization and Hemodynamics in a Multicenter Cohort of Children with Pulmonary Hypertension.

Rationale: Hemodynamic assessments direct care among children with pulmonary hypertension, yet the use of cardiac catheterization is highly variable, which could impact patient care and research. Objectives: We analyzed hemodynamic findings from right heart catheterization (RHC) and left heart catheterization and acute vasodilator testing (AVT) and the safety of catheterization in children with World Symposium on Pulmonary Hypertension (WSPH) group 1 and 3 subtypes in a large multicenter North American cohort. Methods: Of 1,475 children enrolled in the Pediatric Pulmonary Hypertension Network Registry (2014-2020), there were 1,383 group 1 and 3 patients, of whom 671 (48.5%) underwent RHC at diagnosis and were included for analysis. Results: Compared with those without diagnostic RHC, these children were older, less likely to be an infant or preterm, more often female, treated with targeted pulmonary hypertension medications at diagnosis, and had advanced World Health Organization functional class. Catheterization was performed without a difference in complication rates between WSPH groups. Pulmonary capillary wedge pressure was well correlated with left ventricular end-diastolic pressure and left atrial pressures. Results of AVT using three different methods were comparable; positive AVT results were observed in 8.0-11.8% of subjects, did not differ between WSPH groups 1 and 3, and were not associated with freedom from the composite endpoint of lung transplantation or death during follow-up. Conclusions: In a large pediatric pulmonary hypertension cohort, diagnostic RHC with or without left heart catheterization in WSPH group 1 and 3 patients was performed safely at experienced pediatric pulmonary hypertension centers. Hemodynamic differences were noted between group 1 and 3 subjects. Higher mean pulmonary arterial pressure and mean pulmonary arterial pressure/mean systemic arterial pressure ratio were associated with a higher risk of death/transplantation. Findings suggest overall safety and potential value of RHC as a standard diagnostic approach to guide pulmonary hypertension management in children.

Use of inhaled nitric oxide in preterm vs term/near-term neonates with pulmonary hypertension: results of the PaTTerN registry study.

OBJECTIVE: To evaluate inhaled nitric oxide (iNO) in preterm (PT) vs term/near-term (TNT) neonates with hypoxic respiratory failure (HRF) and pulmonary hypertension (PH) in an observational registry (PaTTerN). STUDY DESIGN: Non-inferiority study comparing PT neonates of GA ≥ 27 to <34 weeks vs TNT neonates of GA ≥ 34 to ≤40 weeks with HRF associated with PH, who received iNO for 24-96 h during the first 0-7 days after birth. Primary endpoint: Achieving ≥25% decrease in oxygenation index/surrogate oxygenation index during iNO treatment. RESULTS: Of 140 neonates (PT, n = 55; TNT, n = 85), the primary endpoint was achieved in 50 (90.9%) PT vs 75 (88.2%) TNT neonates (difference [95% CI]: 0.027 [-0.033, 0.087]); PT neonates achieved non-inferiority interval, and the study was stopped early based on prespecified criteria. CONCLUSIONS: Use of iNO for improving oxygenation in PT neonates with HRF associated with PH is at least as effective as in TNT neonates. CLINICAL TRIAL REGISTRATION: #NCT03132428, registered April 27, 2017.

Early Abnormalities in Gas Exchange in Infants with Congenital Diaphragmatic Hernia.

OBJECTIVE: To determine how blood gas exchange is altered during the transition in the first hour of life in infants with congenital diaphragmatic hernia (CDH). STUDY DESIGN: This was a prospective observational cohort study evaluating arterial blood gas (ABG) samples and ventilator support in 34 infants with CDH in the first hour of life. Infants were stratified into mild, moderate, and severe CDH. The first ABG was compared with the umbilical cord ABGs and response to intervention evaluated on subsequent ABGs among infants with different CDH severities. RESULTS: Infants were intubated at a median of 120 seconds (range 50-240 seconds) and ABGs obtained at a median of 6 minutes (IQR 4, 8 minutes), 16 minutes (IQR 13.5, 22.5 minutes), and 60 minutes (IQR 56, 64 minutes). Compared with the cord ABG, first ABG mean partial pressure of carbon dioxide (PaCO2) increased from 49.8 mm Hg to 82.1 mm Hg, mean base deficit decreased from -2.2 to -7.3, and mean pH from 7.298 to 7.060. With ventilator adjustments, second mean PaCO2 decreased to 76.7 mm Hg and third mean PaCO2 48.5 mm Hg. When stratified, with all CDH severities PaCO2 increased abruptly, remained elevated in moderate and severe CDH, and improved in all severities by 60 minutes after delivery. CONCLUSIONS: Gas exchange is markedly altered in the first hour of life in infants with CDH with abrupt onset of acidemia and a mixed respiratory and metabolic acidosis. Early implementation of adequate cardiopulmonary support may contribute to more timely stabilization of gas exchange.

Persistent pulmonary hypertension of the newborn.

Persistent pulmonary hypertension of the newborn (PPHN) is a significant clinical problem characterized by refractory and severe hypoxemia secondary to elevated pulmonary vascular resistance resulting in right-to-left extrapulmonary shunting of deoxygenated blood. PPHN is associated with diverse cardiopulmonary disorders and a high early mortality rate for infants with severe PPHN. Surviving infants with PPHN have an increased risk of long-term morbidities. PPHN physiology can be categorized by (1) maladaptation: pulmonary vessels have normal structure and number but have abnormal vasoreactivity; (2) excessive muscularization: increased smooth muscle cell thickness and increased distal extension of muscle to vessels that are usually not muscularized; and (3) underdevelopment: lung hypoplasia associated with decreased pulmonary artery number. Treatment involves adequate lung recruitment, optimization of cardiac output and left ventricular function, and pulmonary vasodilators such as inhaled nitric oxide. Infants who fail to respond to conventional therapy should be evaluated for lethal lung disorders including alveolar-capillary dysplasia, T-box transcription factor 4 gene, thyroid transcription factor-1, ATP-binding cassette A3 gene, and surfactant protein diseases.

Severe Bronchoconstriction Caused by Administration of Rocuronium in a 3-Month-Old Infant: Case Report.

We present the case of a 3-month-old infant with severe, persistent bronchoconstriction following administration of rocuronium. This observation raises awareness of a rare but potentially life-threatening reaction to neuromuscular blocking agents.

Congenital diaphragmatic hernias: Severe defect grade predicts the need for fundoplication.

Over one-third of infants with congenital diaphragmatic hernia (CDH) eventually require a Nissen fundoplication (NF). We examined pre- and intraoperative predictors for need of a NF in children undergoing CDH repair to elucidate, which patients will need a later NF.A retrospective analysis of all consecutive patients undergoing CDH repair at our institution from 2008 to 2018 was performed. Patients who underwent a NF were compared to those who did not (noNissen). Logistic regression analysis was performed to find independent predictors for NF in patients undergoing CDH repair. Severe Defect Grade was defined as defect >50% of the hemidiaphragm and intrathoracic liver.One hundred twenty-six patients were included, 42 (33%) underwent NF at a median of 61 days after CDH repair. Intrathoracic liver was more frequent in the NF (71%) versus noNissen (45%) group (P = .008). Absence of >50% of the hemidiaphragm was more frequent in the NF group (76% vs 31%, P < .001). Severe Defect Grade emerged as independent predictor for NF (odds ratio 7, 95% confidence interval 3-16, P < .001).Severe Defect Grade emerged as independent predictor for NF after CDH repair.