Occurrence of hyperoxia during iNO treatment for persistent pulmonary hypertension of the newborn: a cohort study

High concentrations of oxygen are often needed to optimize oxygenation in infants with persistent pulmonary hypertension (PPHN), but this can also increase the risk of hyperoxemia. We determined the occurrence of hyperoxemia in infants treated for PPHN. Medical records of infants ≥ 34 + 0 weeks gestational age (GA) who received inhaled nitric oxide (iNO) were retrospectively reviewed for oxygenation parameters during iNO therapy. Oxygen was manually titrated to target arterial oxygen tension (PaO2) 10-13 kPa and peripheral oxygen saturation (SpO2) 92-98%. The main study outcomes were the incidence and duration of hyperoxemia and hypoxemia and the fraction of inspired oxygen (FiO2). A total of 181 infants were included. The median FiO2 was 0.43 (IQR 0.34-0.56) and the maximum FiO2 was 1.0 in 156/181 (86%) infants, resulting in at least one PaO2 > 13 kPa in 149/181 (82%) infants, of which 46/149 (31%) infants had minimal one PaO2 > 30 kPa. SpO2 was > 98% in 179/181 (99%) infants for 17.7% (8.2-35.6%) of the iNO time. PaO2 < 10 kPa occurred in 160/181 (88%) infants, of which 81/160 (51%) infants had minimal one PaO2 < 6.7 kPa. SpO2 was < 92% in 169/181 (93%) infants for 1.6% (0.5-4.3%) of the iNO time.    Conclusion: While treatment of PPHN is focused on preventing and reversing hypoxemia, hyperoxemia occurs inadvertently in most patients. What is Known: • High concentrations of oxygen are often needed to prevent hypoxemia-induced deterioration of PPHN, but this can also increase the risk of hyperoxemia. • Infants with persistent pulmonary hypertension may be particularly vulnerable to the toxic effects of oxygen, and hyperoxemia could further induce pulmonary vasoconstriction, potentially worsening the condition. What is New: • Hyperoxemia occurs in the majority of infants with PPHN during treatment with iNO. • Infants with PPHN spent a considerably longer period with saturations above the target range compared to saturations below the target range.

Neonatal Diagnosis of Alveolar Capillary Dysplasia via Rapid Genomic Sequencing: A New Gold Standard?

Classic alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV) is a rare congenital lung disorder presenting in the early neonatal period with refractory hypoxemic respiratory failure and pulmonary hypertension. No curative treatment is currently available. Although definitive diagnosis is obtained by histology, lung biopsy is often challenging in unstable, critically ill neonates. Molecular diagnosis has been achieved with chromosomal microarray and targeted gene sequencing; however, each of these modalities can be limited by turnaround time, coverage of the genome, and inability to detect all pathogenic variant types for ACDMPV. We present a case of ACDMPV diagnosed via rapid genome sequencing and posit that rapid genomic sequencing, including both rapid exome and genome sequencing, has an expanding role in severe neonatal respiratory failure as a comprehensive and noninvasive approach to timely diagnosis.

Distinctive clinical features of spontaneous pneumoperitoneum in neonates: A retrospective analysis

BACKGROUND

Spontaneous pneumoperitoneum (SP) without gastrointestinal perforation rarely occurs in neonates, with most SP cases being idiopathic. Although SP usually follows a benign clinical course with favorable prognosis, it can become life-threatening in certain situations. In these cases, urgent surgical intervention may be required. Therefore, it may be difficult to decide when or how to perform prompt interventions.

AIM

To demonstrate the distinct clinical features of SP to guide appropriate management by comparing characteristics between SP and typical pneumoperitoneum secondary to gastrointestinal perforation.

METHODS

We retrospectively reviewed electronic medical records and identified 37 neonates with radiological evidence of pneumoperitoneum who were treated at our institution. Clinical variables were compared between neonates with SP without gastrointestinal perforation (Group A) and those with pneumoperitoneum secondary to gastrointestinal perforation (Group B). Clinical variables between groups were compared using Student’s t-test and the chi-square test. The risk factors related to mortality were examined using multi-logistic regression analysis.

RESULTS

Group A comprised 35.1% (13/37) of the patients. The frequency of persistent pulmonary hypertension (53.8%) and pneumothorax (46.2%) before the development of pneumoperitoneum was significantly higher in group A than in group B (P = 0.004). Platelet count and partial pressure of arterial oxygen (PaO2) were significantly lower in group A (P = 0.015 and 0.025, respectively). Overall mortality was significantly higher in group A than in group B (76.9% vs 16.7%, P = 0.001). Only preterm infants were significantly associated with high mortality (P = 0.041; odds ratio = 18.0). Accompaniment with persistent pulmonary hypertension and pneumothorax were also significantly high (P = 0.004) in group A, but these were not strongly associated with high mortality.

CONCLUSION

This study identified a higher mortality rate in patients with SP than that described in previous reports. Neonates with SP were more likely to have thrombocytopenia, pneumothorax, and persistent pulmonary hypertension. Prematurity was the most significant factor affecting mortality.

Pulmonary hypertension and oxidative stress: Where is the link?

Oxidative stress can be associated with hyperoxia and hypoxia and is characterized by an increase in reactive oxygen (ROS) and nitrogen (RNS) species generated by an underlying disease process or by supplemental oxygen that exceeds the neutralization capacity of the organ system. ROS and RNS acting as free radicals can inactive several enzymes and vasodilators in the nitric oxide pathway promoting pulmonary vasoconstriction resulting in persistent pulmonary hypertension of the newborn (PPHN). Studies in animal models of PPHN have shown high ROS/RNS that is further increased by hyperoxic ventilation. In addition, antioxidant therapy increased PaO2 in these models, but clinical trials are lacking. We recommend targeting preductal SpO2 between 90 and 97%, PaO2 between 55 and 80 mmHg and avoiding FiO2 > 0.6-0.8 if possible during PPHN management. This review highlights the role of oxidative and nitrosative stress markers on PPHN and potential therapeutic interventions that may alleviate the consequences of increased oxidant stress during ventilation with supplemental oxygen.

[Application of extracorporeal membrane oxygenation in the treatment of persistent pulmonary hypertension of the newborn]

OBJECTIVES

To study the clinical value of extracorporeal membrane oxygenation (ECMO) in the treatment of persistent pulmonary hypertension of the newborn (PPHN).

METHODS

A retrospective analysis was performed on the medical data of 11 neonates with PPHN who were treated with ECMO in the Neonatal Intensive Care Unit of Zhongshan People's Hospital from January 2015 to December 2021, involving the neonates' general information, clinical diagnosis, laboratory results, duration of ECMO treatment, complications during ECMO treatment, length of hospital stay, and outcome.

RESULTS

Of the 11 neonates, 10 (91%) had successful weaning from ECMO, and 8 (73%) survived. For the 11 neonates, the mean duration of ECMO treatment was (81±50) hours (range: 26 to 185 hours), the mean duration of ventilator use was (198±105) hours (range: 57 to 392 hours), and the mean length of hospital stay was (22±15) days (range: 2 to 49 days). The oxygenation index and blood lactate level were significantly improved after 24 hours of ECMO treatment among the 11 neonates (P<0.05). Ten neonates had significantly reduced pulmonary artery pressure after 24 hours of ECMO treatment (P<0.05). One neonate had a progressive increase in the pulmonary artery pressure during EMCO treatment, succumbing to death. This neonate was diagnosed with alveolar capillary dysplasia based on the histopathological findings of the lung tissue and whole-exome sequencing results. Among the 11 children, 5 had intracranial hemorrhage, 1 had disseminated intravascular coagulation, 1 had gastric hemorrhage, 2 had pulmonary hemorrhage, 1 had renal insufficiency, and 3 had bleeding at the puncture site during ECMO treatment.

CONCLUSIONS

ECMO is effective for the treatment of PPHN, however, the high incidence of complications of ECMO treatment suggests that it is important to carefully assess the indications and timing of ECMO treatment and improve the management of ECMO, which can improve the weaning rate and survival rate.

[Early risk factors for death in neonates with persistent pulmonary hypertension of the newborn treated with inhaled nitric oxide]

OBJECTIVES

To evaluate the early risk factors for death in neonates with persistent pulmonary hypertension of the newborn (PPHN) treated with inhaled nitric oxide (iNO).

METHODS

A retrospective analysis was performed on 105 infants with PPHN (gestational age ≥34 weeks and age <7 days on admission) who received iNO treatment in the Department of Neonatology, Children's Hospital of Nanjing Medical University, from July 2017 to March 2021. Related general information and clinical data were collected. According to the clinical outcome at discharge, the infants were divided into a survival group with 79 infants and a death group with 26 infants. Univariate and multivariate Cox regression analyses were used to evaluate the risk factors for death in infants with PPHN treated with iNO. The receiver operating characteristic (ROC) curve was used to calculate the cut-off values of the factors in predicting the death risk.

RESULTS

A total of 105 infants with PPHN treated with iNO were included, among whom 26 died (26/105, 24.8%). The multivariate Cox regression analysis showed that no early response to iNO (HR=8.500, 95%CI: 3.024-23.887, P<0.001), 1-minute Apgar score ≤3 points (HR=10.094, 95%CI: 2.577-39.534, P=0.001), a low value of minimum PaO2/FiO2 within 12 hours after admission (HR=0.067, 95%CI: 0.009-0.481, P=0.007), and a low value of minimum pH within 12 hours after admission (HR=0.049, 95%CI: 0.004-0.545, P=0.014) were independent risk factors for death. The ROC curve analysis showed that the lowest PaO2/FiO2 value within 12 hours after admission had an area under the ROC curve of 0.783 in predicting death risk, with a sensitivity of 84.6% and a specificity of 73.4% at the cut-off value of 50, and the lowest pH value within 12 hours after admission had an area under the ROC curve of 0.746, with a sensitivity of 76.9% and a specificity of 65.8% at the cut-off value of 7.2.

CONCLUSIONS

Infants with PPHN requiring iNO treatment tend to have a high mortality rate. No early response to iNO, 1-minute Apgar score ≤3 points, the lowest PaO2/FiO2 value <50 within 12 hours after admission, and the lowest pH value <7.2 within 12 hours after admission are the early risk factors for death in such infants. Monitoring and evaluation of the above indicators will help to identify high-risk infants in the early stage.

Efficacy and safety of bosentan in the treatment of persistent pulmonary hypertension of the newborn: a Metaanalysis

OBJECTIVES

To systematically evaluate the efficacy and safety of bosentan in the treatment of persistent pulmonary hypertension of the newborn (PPHN).

METHODS

Chinese Journal Full-text Database, Weipu Database, Wanfang Data, China Biology Medicine disc, PubMed, Web of Science, Embase, and Cochrane Library were searched for literature on bosentan in the treatment of PPHN published up to August 31, 2021.

RESULTS

A total of 8 randomized controlled trials were included for Meta analysis. The results of the Meta analysis showed that compared with the control group, the bosentan treatment group had a significantly lower treatment failure rate (RR=0.23, P<0.001), a significantly greater reduction in pulmonary artery pressure [mean difference (MD)=-11.79, P<0.001)], significantly greater increases in oxygen partial pressure (MD=10.21, P=0.006) and blood oxygen saturation (MD=8.30, P<0.001), and a significantly shorter length of hospital stay (MD=-1.35, P<0.001). The descriptive analysis showed that the bosentan treatment group had a lower degree of tricuspid regurgitation than the control group after treatment. The main adverse reactions of bosentan treatment included abnormal liver function, anemia and edema. The results of subgroup analysis based on treatment regimen, research area, and drug dose were consistent with those before stratification.

CONCLUSIONS

Bosentan is effective in the treatment of PPHN. However, when using bosentan, attention should be paid to adverse reactions such as abnormal liver function.

Association of asymmetric dimethylarginine with the pathological process of persistent pulmonary hypertension of the newborn

OBJECTIVES

To study the change in asymmetric dimethylarginine (ADMA) in the circulation system of full-term infants with persistent pulmonary hypertension of the newborn (PPHN) and its association with treatment response, as well as the possibility of ADMA as a therapeutic target and a marker for treatment response.

METHODS

A prospective study was performed. A total of 30 full-term neonates who were diagnosed with PPHN within 3 days after birth were enrolled as the PPHN group, and the neonates without PPHN, matched for gestational age and age, who were treated or observed in the department of neonatology were enrolled as the control group. Serum samples were collected on days 1, 7, and 14 of treatment. The high-performance liquid chromatography-tandem mass spectrometry was used to measure the serum concentrations of L-arginine, ADMA, and its isomer symmetric dimethylarginine (SDMA).

RESULTS

For the neonates in the control group, the serum concentrations of ADMA and L-arginine continuously increased and the serum concentration of SDMA continuously decreased within the first 14 days of treatment. On days 1 and 14, there was no significant difference in the serum concentration of ADMA between the control and PPHN groups (P>0.05). On day 7, the PPHN group had a significantly higher serum concentration of ADMA than the control group (P<0.05), while there were no significant differences in serum concentrations of SDMA or L-arginine (P>0.05). Moreover, after 7 days of treatment, the PPHN neonates with a systolic pulmonary arterial pressure (sPAP) of >35 mmHg had a significantly higher serum concentration of ADMA than those with an sPAP of ≤35 mm Hg.

CONCLUSIONS

There are continuous increases in the ADMA concentration and the ADMA/SDMA ratio in the circulation system of full-term infants within the first 2 weeks after birth, and this process is accelerated by the pathological process of PPHN, suggesting that ADMA may be involved in the pathologic process of PPHN. A high level of ADMA is associated with the resistance to PPHN treatment, suggesting that inhibition of ADMA might be a potential target of drug intervention to improve the treatment response of PPHN.

Prevalence of pulmonary hypertension among children with Down syndrome: A systematic review and meta-analysis

BACKGROUND

Pulmonary hypertension (PH) has serious short- and long-term consequences. PH is gaining increasing importance in high risk groups such as Down syndrome (DS) as it influences their overall survival and prognosis. Hence, there is a dire need to collate the prevalence rates of PH in order to undertake definitive measures for early diagnosis and management.

AIM

To determine the prevalence of PH in children with DS.

METHODS

The authors individually conducted a search of electronic databases manually (Cochrane library, PubMed, EMBASE, Scopus, Web of Science). Data extraction and quality control were independently performed by two reviewers and a third reviewer resolved any conflicts of opinion. The words used in the literature search were “pulmonary hypertension” and “pulmonary arterial hypertension”; “Down syndrome” and “trisomy 21” and “prevalence”. The data were analyzed by Comprehensive Meta-Analysis Software Version 2. Risk of bias assessment and STROBE checklist were used for quality assessment.

RESULTS

Of 1578 articles identified, 17 were selected for final analysis. The pooled prevalence of PH in these studies was 25.5%. Subgroup analysis was carried out for age, gender, region, year of publication, risk of bias and etiology of PH.

CONCLUSION

This review highlights the increasing prevalence of PH in children with DS. It is crucial for pediatricians to be aware of this morbid disease and channel their efforts towards earlier diagnosis and successful management. Community-based studies with a larger sample size of children with DS should be carried out to better characterize the epidemiology and underlying etiology of PH in DS.

Postnatal causes and severity of persistent pulmonary Hypertension of Newborn

Background & Objective:

Persistent pulmonary hypertension of the newborn (PPHN) is described as severe respiratory failure along with hypoxaemia. PPHN is known to be linked with high morbidity and mortality around the world. This study was planned to determine the postnatal causes and assess the severity of persistent pulmonary hypertension of newborn in babies presenting to the Children’s Hospital, Multan.

Methods:

This observational study was conducted at the Department of Paediatric Cardiology, The Children Hospital &Institute of Child Health, Multan, Pakistan from July to December 2019. A total of 122 confirmed cases of PPHN admitted having gestational age above 34 weeks were enrolled. Demographic data of the newborns was recorded along with maternal medical history, pregnancy status and postnatal causes of PPHN. Severity of PPHN was also recorded.

Results:

Out of a total of 122 cases of PPHN, 81 (66.3%) were male. Majority, 78 (64.0%) had gestational age above 37 weeks. Mode of delivery as cesarean section was noted in 70 (57.4%). Meconium aspiration syndrome 52 (42.6%), birth asphyxia 48 (39.3%), respiratory distress syndrome 23 (18.8%) and sepsis 33 (27.0%) were found to be the commonest causes of PPHN. Severe PPHN was found to be the most frequent, noted among 63 (51.6%) while Moderate PPHN was observed in 40 (32.8%) and Mild PPHN in 19 (15.6%). Morality was noted among 26 (21.3%) of cases.

Conclusion:

Meconium aspiration syndrome, birth asphyxia and respiratory distress syndrome were the commonest postnatal causes of PPHN. Severe PPHN was found to be the most frequent form of PPHN.

Utility of Low Dose Vasopressin for Persistent Pulmonary Hypertension of Newborn with Catecholamine Refractory Shock

OBJECTIVE

To evaluate the effect of low dose vasopressin on the hemodynamics of neonates with persistent pulmonary hypertension and catecholamine refractory shock.

METHODS

This retrospective study was conducted in a level III NICU of a tertiary care teaching hospital, south India. Eighteen neonates with hypoxemic respiratory failure due to persistent pulmonary hypertension of newborn with catecholamine refractory shock were studied. Neonates were managed for hypotension with conventional inotropic support with the additional use of low dose vasopressin (LDV). Effect of vasopressin on oxygenation index (OI), blood pressure, duration of inotropic usage and survival was evaluated.

RESULTS

Mean OI was 38.2 ± 4.9, and mean blood pressure was 30.7 ± 5.3 mmHg before the start of vasopressin. Initiation of LDV (0.0003 ± 0.0001 IU/kg/min) for a median duration 36.4 ± 17.9 h was followed by a reduction in OI (p < 0.001), control of hypotension (p < 0.001), reduction in lactic acidosis (p < 0.001) and decline in inotropic support.

CONCLUSIONS

In resource-restricted settings, LDV may be useful as a rescue therapy for persistent pulmonary hypertension of newborn with catecholamine refractory shock.

Morbidity of conversion from venovenous to venoarterial ECMO in neonates with meconium aspiration or persistent pulmonary hypertension

BACKGROUND

Outcomes in neonates receiving extracorporeal membrane oxygenation (ECMO) for meconium aspiration syndrome (MAS) and/or persistent pulmonary hypertension (PPHN) are favorable. Infants with preserved perfusion are often offered venovenous (VV) support to spare morbidities of venoarterial (VA) ECMO. Worsening perfusion or circuit complications can prompt conversion from VV-to-VA support. We examined whether outcomes in infants requiring VA ECMO for MAS/PPHN differed if they underwent VA support initially versus converting to VA after a VV trial, and what factors predicted conversion.

METHODS

We reviewed the Extracorporeal Life Support Organization registry from 2007 to 2017 for neonates with primary diagnoses of MAS/PPHN. Propensity score analysis matched VA single-runs (controls) 4:1 against VV-to-VA conversions based on age, pre-ECMO pH, and precannulation arrests. Primary outcomes were complications and survival. Data were analyzed using Mann-Whitney U and Fisher's exact testing. Multivariate regression identified independent predictors of conversion for VV patients.

RESULTS

3831 neonates underwent ECMO for MAS/PPHN, including 2129 (55%) initially requiring VA support. Of 1702 patients placed on VV ECMO, 98 (5.8%) required VV-to-VA conversion. Compared with 364 propensity-matched isolated VA controls, conversion runs were longer (190 vs. 127 h, P < 0.001), were associated with more complications, and decreased survival to discharge (70% vs. 83%, P = 0.01). On multivariate regression, conversion was more likely if neonates on VV ECMO did not receive surfactant (OR = 1.7;95%CI = 1.1-2.7;P = 0.03) or required high-frequency ventilation (OR = 1.9;95%CI = 1.2-3.3;P = 0.01) before ECMO.

CONCLUSION

Conversion from VV-to-VA ECMO in infants with MAS/PPHN conveys increased morbidity and mortality compared to similar patients placed initially onto VA ECMO. VV patients not receiving surfactant or requiring high-frequency ventilation before cannulation may have increased risk of conversion. While conversions remain rare, decisions to offer VV ECMO for MAS/PPHN must be informed by inferior outcomes observed should conversion be required.

LEVEL OF EVIDENCE

Level of evidence 3 Retrospective comparative study.

PPHN and oxidative stress: a review of literature

Persistent pulmonary hypertension of the neonate is a multifactorial condition characterized by maladaptive pulmonary vascular remodeling and abnormal contractile reactivity. This review evaluates the role of oxidative stress and antioxidant treatment on the persistent pulmonary hypertension of the neonate.

A review of filamin A mutations and associated interstitial lung disease

The filamin A gene (FLNA) on Xq28 encodes the filamin A protein. Mutation in FLNA causes a wide spectrum of disease including skeletal dysplasia, neuronal migration abnormality, cardiovascular malformation, intellectual disability and intestinal obstruction. Recently, childhood-onset interstitial lung disease associated with a range of FLNA mutations has been recognised and reported. We document our personal experience of this emerging disorder and compile a comprehensive overview of clinical features and molecular changes in all identifiable published cases. Reviewing the emerging dataset, we underline this unanticipated phenotypic consequence of pathogenic FLNA mutation-associated pulmonary disease.Conclusion: From the emerging data, we suggest that while reviewing complex cases with a sustained oxygen requirement against a clincial background of cardiac concerns or intestinal obstruction to have a high index of suspicion for FLNA related pathology and to instigate early MRI brain scan and FLNA mutation analysis. What is Known: • FLNA gene on Xq28 encodes the filamin A protein and mutation therein is associated with variable phenotypes depending on its nature of mutation. • Loss-of-function mutation of filamin A is associated with X-linked inherited form of periventricular nodular heterotopia with or without epilepsy with most individuals affected being female. There is a recently recognised associated respiratory phenotype. What is New: • The respiratory phenotype in the form of childhood interstitial lung disease is a recently recognised clinical consequence of loss-of-function FLNA mutation. • Rare male patients with loss-of-function FLNA mutation-associated lung disease with residual protein function can survive into infancy with a severe form of the phenotype.

Lung Ultrasound to Assess the Etiology of Persistent Pulmonary Hypertension of the Newborn (LUPPHYN Study): A Pilot Study

INTRODUCTION

Persistent pulmonary hypertension of the newborn (PPHN) is a neonatal syndrome associated with significant morbidity and mortality that is caused by the failure of postnatal drop in pulmonary vascular resistance. In extreme cases, patients may require extracorporeal membrane oxygenation therapy (ECMO). The aim of this study was to explore lung ultrasound (LUS) patterns in newborns with PPHN requiring ECMO.

PATIENTS AND METHODS

From January 2014 to January 2018, LUS was performed on patients with PPHN admitted for ECMO treatment. PPHN diagnosis was based on clinical and echocardiographic findings. LUS was performed before patients underwent ECMO cannulation. An underlying diagnosis was made taking into account the patient's complete medical history, excluding LUS information. A blinded physician, unaware of the patient's clinical condition, analyzed the stored ultrasound images. Results were then compared with chest x-ray (CXR) diagnoses.

RESULTS

Seventeen patients were recruited; 12 were male (70.6%). The median gestational age was 38.7 weeks, with 13 term newborns (76.5%). Twelve were cannulated for VA ECMO, with a median ECMO run of 111.2 h. Six patients (35%) survived. Patients with alveolar capillary dysplasia with misaligned pulmonary veins, fetal ductus arteriosus constriction, or sepsis had normal LUS patterns (A-lines with lung sliding). LUS showed a better sensitivity (88.9%) and specificity (85%) than CXR (55.6 and 77.5%, respectively) in identifying patients with nonparenchymal lung disease.

CONCLUSIONS

LUS can provide essential information to help diagnose the underlying cause of PPHN in an earlier and more effective way than CXR. LUS is suitable for routine utilization in the intensive care unit.

Review shows that implementing a nationwide protocol for congenital diaphragmatic hernia was a key factor in reducing mortality and morbidity

The French Rare Disease Reference Center for congenital diaphragmatic hernia (CDH) was created in 2008, to implement a national protocol for foetuses and children with this serious condition. Neonatal mortality from CDH is 30-40%, mainly due to pulmonary hypoplasia and persistent pulmonary hypertension, and half of those who live have high respiratory, nutritional and digestive morbidity. CDH management requires long-term and specialised multidisciplinary care. It has been well established that a standardised management protocol improves the prognosis of children with CDH.

CONCLUSION

Organising health care and implementing a nationwide French protocol were key factors for reducing mortality and morbidity from CDH.

Comparison Of The Efficacy Of Sildenafil Alone Versus Sildenafil Plus Bosentan In Newborns With Persistent Pulmonary Hypertension

BACKGROUND

Persistent pulmonary hypertension is a serious disease among new-borns. Inhaled nitric oxide is first line of therapy along with extracorporeal membrane oxygenation. Pulmonary vasodilators such as sildenafil, bosentan and milrinone are also used to treat persistent pulmonary hypertension especially in resource limited centres where inhaled nitric oxide is not available. The objective of this study was to compare the effect of sildenafil alone and sildenafil with bosentan on severity of tricuspid regurgitation and duration of hospitalization in new-borns with persistent pulmonary hypertension.

METHODS

This was single blinded clinical trial conducted at The Children's Hospital & the Institute of Child Health, Multan, Pakistan, from July 2016 to December 2016. New-borns with pulmonary hypertension were admitted and divided into two groups. Group A was treated with sildenafil (2mg per kg per dose three times a day) and group B with both sildenafil (2 mg per kg per dose three times a day) and bosentan (1 mg per kg per dose twice a day).

RESULTS

There were 50 new-borns in each group. The mean age, sex distribution and baseline TR measurement (mmHg) at the time of admission was similar in both the groups. Measurement of TR (mmHg) after 72 hours admission was significantly less in Group B as compared to group A (11±4.62 versus 23±4.78), p-value<0.0001. The mean duration of hospital stays (days) was 10.12±5.20 in group A and 7.56±3.77 in group B (p-value <0.0001). There was no mortality in any group and no case of hypotension in both groups.

CONCLUSIONS

The combined use of sildenafil and bosentan is more effective than sildenafil alone for control of pulmonary hypertension in resource limited centres.

An overview of medical ECMO for neonates

Extracorporeal membrane oxygenation (ECMO), a life-saving therapy for respiratory and cardiac failure, was first used in neonates in the 1970s. The indications and criteria for ECMO have changed over the years, but it continues to be an important option for those who have failed other medical therapies. Since the Extracorporeal Life Support Organization (ELSO) Registry was established in 1989, more than 29,900 neonates have been placed on ECMO for respiratory failure, with 84% surviving their ECMO course, and 73% surviving to discharge or transfer. In this chapter, we will review the basics of ECMO, patient characteristics and criteria, patient management, ECMO complications, special uses of neonatal ECMO, and patient outcomes.

Milrinone in congenital diaphragmatic hernia - a randomized pilot trial: study protocol, review of literature and survey of current practices

Background

Congenital diaphragmatic hernia (CDH) is commonly associated with pulmonary hypoplasia and pulmonary hypertension (PH). PH associated with CDH (CDH-PH) is frequently resistant to conventional pulmonary vasodilator therapy including inhaled nitric oxide (iNO) possibly due to right and left ventricular dysfunction. Milrinone is an intravenous inotrope and lusitrope with pulmonary vasodilator properties and has been shown anecdotally to improve oxygenation in PH. We developed this pilot study to determine if milrinone infusion would improve oxygenation in neonates ≥36 weeks postmenstrual age (PMA) with CDH.

Methods/design

Data on pulmonary vasodilator management and outcome of CDH patients was collected from 18 university NICUs affiliated with the Neonatal Research Network (NRN) from 2011 to 2012. The proposed pilot will be a masked, placebo–controlled, multicenter, randomized trial of 66 infants with CDH with an oxygenation index (OI) ≥10 or oxygen saturation index (OSI) ≥5. The primary outcome is the oxygenation response, as determined by change in OI at 24 h after initiation of study drug. As secondary outcomes, we will determine oxygenation at 48 h and 72 h post-infusion, right ventricular pressures on echocardiogram and the incidence of systemic hypotension, arrhythmias, intracranial hemorrhage, survival without extracorporeal membrane oxygenation, and chronic lung disease (oxygen need at 28 days postnatal age). Finally, we will evaluate the pulmonary and nutritional status at 4, 8 and 12 months of age using a phone questionnaire.

Results

Three hundred thirty-seven infants with CDH were admitted to NRN NICUs in 2011 and 2012 of which 275 were ≥36 weeks PMA and were exposed to the following pulmonary vasodilators: iNO (39%), sildenafil (17%), milrinone (17%), inhaled epoprostenol (6%), intravenous epoprostenol (3%), and intravenous PGE1 (1%). ECMO was required in 36% of patients. Survival to discharge was 71%.

Discussion

CDH is an orphan disease with high mortality with few randomized trials evaluating postnatal management. Intravenous milrinone is a commonly used medication in neonatal/pediatric intensive care units and is currently used in 17% of patients with CDH within the NRN. This pilot study will provide data and enable further studies evaluating pulmonary vasodilator therapy in CDH.

Trial registration

ClinicalTrials.gov; NCT02951130; registered 14 October 2016.

Servo controlled versus manual cooling methods in neonates with hypoxic ischemic encephalopathy

BACKGROUND

Therapeutic hypothermia is known to improve outcomes in neonates with hypoxic ischemic encephalopathy (HIE). There are no studies that have compared servo controlled cooling (SCC) versus manually controlled cooling (MCC) methods in HIE.

AIM

To compare the outcomes of SCC versus MCC in neonates with HIE.

METHODS AND OUTCOME MEASURES

Between Jan 2008 and May 2011, MCC with cool-gel packs was used to achieve rectal temperatures of 33.5 to 34.5°C in our units. Subsequently, we changed to SCC to achieve rectal temperatures of 33 to 34°C. 105 neonates received SCC whereas 95 received MCC. Retrospective study with multivariate analysis was conducted comparing thermoregulation (primary outcome) and neurodevelopmental outcomes of SCC versus MCC.

RESULTS

In the SCC group, 72.3% had stage 2 or 3 HIE versus 77.9% in the MCC. The remaining had stage 1, but attending neonatologists decided to provide cooling. Prescribed rectal temperatures were achieved in 80.5% (5768/7168) instances in SCC versus 72.9% (4449/6108) in MCC (p<0.0001). There were no significant differences in the incidence of 'death or moderate-severe disability' [SCC 26/85 vs MCC 26/87, adjusted odds ratio: 1.29, 95% CI: 0.48, 3.42; p=0.614]. The results were similar after excluding stage 1 HIE [SCC 25/66 vs MCC 26/69, adjusted odds ratio: 1.01, 95% CI: 0.50, 2.02; p=0.981].

CONCLUSIONS

SCC resulted in better thermoregulation in neonates undergoing therapeutic hypothermia. There were no significant differences in neurodevelopmental outcomes, but the study was underpowered to answer this. Randomized trials are needed to fine-tune various aspects of TH in neonates with HIE.

Severe persistent pulmonary hypertension of the newborn and dysmorphic features in neonate with a deletion involving TWIST1 and PHF14: a case report

Background

Persistent pulmonary hypertension is a well-known disease of the newborn that in most cases responds well to treatment with nitric oxide and treatment of any underlying causes. Genetic causes of persistent pulmonary hypertension of the newborn are rare. The TWIST1 gene is involved in morphogenetics, and deletions are known to cause Saethre-Chotzen syndrome. Deletions of PHF14 have never been reported in neonates, but animal studies have shown a link between severe defects in lung development and deletions of this gene. There have not, to the best of our knowledge, been any publications of a link between the genes TWIST1 and PHF14 and persistent pulmonary hypertension of the newborn, making this a novel finding.

Case presentation

We describe a white male neonate born at term to non-consanguineous white parents; he presented with dysmorphic features and a therapy-refractory persistent pulmonary hypertension. Array-based comparative genomic hybridization revealed the presence of a 14.7 Mb interstitial deletion on chromosome 7, encompassing the genes TWIST1 and PHF14.

Conclusions

The TWIST1 gene can explain our patient’s dysmorphic features. His severe persistent pulmonary hypertension has, however, not been described before in conjunction with the TWIST1 gene, but could be explained by involvement of PHF14, consistent with findings in animal experiments showing lethal respiratory failure with depletion of PHF14. These findings are novel and of importance for the clinical management and diagnostic workup of neonates with severe persistent pulmonary hypertension of the newborn and dysmorphic features.

Echocardiographic predictors of poor prognosis in congenital diaphragmatic hernia

BACKGROUND/PURPOSE

The purpose of this study was to investigate echocardiographic parameters in relation to the outcomes of isolated left-sided congenital diaphragmatic hernia (CDH).

METHODS

This multicenter, retrospective, observational study was conducted among patients with CDH born between 2006 and 2010. Patients in this study did not have severe cardiac malformations or chromosomal aberrations. Patients with incomplete echocardiographic examinations were excluded. In total, 84 patients with left-sided isolated CDH were included in this study. The prognostic parameters were obtained from postnatal echocardiographic images within 24h after birth.

RESULTS

Eight patients died before 90days of birth. Univariate analysis showed that the presence of continuous right to left shunt at the ductus, left pulmonary artery diameter of <2.7mm, right pulmonary artery diameter of <3.3mm, and left ventricular diastolic diameter of <10.8mm, were the predictors of poor prognosis. Multivariate logistic regression analysis showed that right pulmonary artery diameter of <3.3mm (adjusted OR 10.28, 95% C.I.: 1.15-249.19) and left ventricular diastolic diameter of <10.8mm (adjusted OR 7.86, 95% C.I.: 1.01-82.82) were predictors of poor prognosis.

CONCLUSIONS

This study revealed that the predictors of poor prognosis associated with CDH include smaller right pulmonary artery and left ventricular diastolic diameters. Retrospective Study-Level II.

Predictors of persistent pulmonary hypertension after mitral valve replacement

Persistent pulmonary hypertension (P-PH) after mitral valve replacement (MVR) leads to an increased risk of morbidity and mortality. We sought to determine which factors were involved in its occurrence. Patients undergoing MVR for a 3-year period were collected in a retrospective way. We excluded those with an available follow-up shorter than 3 months. Sample size was 111 patients. PH was diagnosed if systolic pulmonary artery pressure (sPAP) estimated by Doppler echocardiography was >40 mmHg. Clinical, echocardiographic, and surgical factors were analyzed. P-PH was present in 42.3 % of patients after 12.6 months of mean follow-up. P-PH was more frequently observed in elderly and female patients, in those with severe degrees of PH before surgery, and significant tricuspid regurgitation (TR). On multivariable analysis, significant TR (OR 1.739; p = 0.01) and more severe degrees of PH before surgery (OR 1.761; p = 0.03) were significantly associated with the presence of P-PH after MVR. Surgical factors related to P-PH were prosthesis size and tricuspid annuloplasty: no need for the performing of tricuspid annuloplasty (OR 0.345; p = 0.025) and the implantation of a smaller prosthesis (OR 0.656; p = 0.004) were related to higher rates of P-PH after MVR. MVR was associated with high prevalence of P-PH after mid-term follow-up. Both PH and significant TR before surgery were associated with P-PH. Our data point out that MVR should be planned before the development of PH and greater TR. Smaller prosthetic size is also a risk factor for P-PH and bigger prostheses are desirable when possible.

Safety of milrinone use in neonatal intensive care units

BACKGROUND

Milrinone use in the neonatal intensive care unit has increased over the last 10 years despite a paucity of published safety data in infants. We sought to determine the safety of milrinone therapy among infants in the neonatal intensive care unit.

METHODS

We conducted a retrospective data analysis, identifying all infants who were exposed to milrinone and discharged from 322 neonatal intensive care units managed by the Pediatrix Medical Group from 1997-2010. We identified adverse events (AEs) during milrinone exposure. The unit of observation for clinical AEs was the first course of milrinone and for laboratory AEs it was an infant-day of exposure to milrinone.

RESULTS

Overall, 1446 of 716,821 (0.2%) infants received milrinone for a total of 6894 infant-days. The proportion of infants exposed to milrinone increased from 0 in 1997 to 4/1000 infant cases in 2010. Persistent pulmonary hypertension (40%) was the most commonly reported diagnosis at the start of milrinone administration. Overall, 606/1446 (42%) of infants had at least 1 clinical AE recorded during milrinone therapy. Hypotension requiring pressors and thrombocytopenia (<100,000/mm(3)) were the most commonly reported clinical and laboratory AEs, respectively. Death was reported in 8% of infants during the first course of milrinone therapy.

CONCLUSION

Among infants hospitalized in the neonatal intensive care unit, there was an increase in the use of milrinone over the past 13 years. The safety, dosing, and efficacy of milrinone in infants should be determined in prospective clinical trials.

Selective serotonin reuptake inhibitors in human pregnancy: on the way to resolving the controversy

There has been an increase in the use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy. However, in the last 10 years, in spite of a vast literature regarding use in pregnancy there seems to be some confusion as to the possible risk of these drugs, especially related to cardiovascular anomalies. In addition, there are data on developmental follow-up studies that raise the question of possible slight developmental and neurobehavioral problems. The purpose of the present review is therefore to critically summarize the current evidence for the risk/benefit analysis of SSRI use in human pregnancy. Although most studies have not shown an increase in the overall risk of major malformations, several have suggested that the use of SSRIs may be associated with a small increased risk for cardiovascular malformations. However, new compelling evidence shows that this apparent increased risk occurs also in women with untreated depression, highlighting the probable ascertainment bias involved in many of these studies. Persistent pulmonary hypertension of the newborn (PPHN) has also been described with an absolute risk of <1%; however, here too, higher rates were described among offspring of women with untreated depression. Poor neonatal adaptation has been described in up to 30% of neonates exposed to SSRIs late in pregnancy. Of the few postnatal developmental follow-up studies, there are no significant developmental problems. The literature on SSRIs in pregnancy is somewhat confusing but when analysing all prospective cohort data there seems to be no demonstrable increase in the rate of major anomalies or developmental disorders. When evaluating the risk/benefit ratio of SSRI treatment in pregnancy, the risk associated with treatment discontinuation - e.g. higher frequency of relapse, increased risk of preterm delivery and postpartum depression - appear to outweigh the potential, unproven risks of treatment. Moreover, maternal depression may negatively affect the child's development, emphasizing the importance of prevention by appropriate treatment during pregnancy with the least minimal effective dose.

Risk factors and mortality among newborns with persistent pulmonary hypertension

Objective: To determine the risk factors for persistent pulmonary hypertension of newborns (PPHN) and their influence on mortality.

Methods: This was an observational study conducted at The Children’s Hospital & the Institute of Child Health, Multan, Pakistan, from July 2011 to June 2012.All admitted babies who had respiratory distress, cyanosis and evidence of hypoxia on ABG,s were diagnosed provided that they were having right- to- left or bidirectional hemodynamic shunting at the ductus arteriosus or at patent foramen ovale along with Tricuspid regurgitation (TR) jet >40 mm of Hg on echocardiography. All the demographic, maternal, antenatal, natal and postnatal data were recorded on a predesigned Performa.

Results: There were 79 patients, including 61 males and 18 females. The most common risk factors observed in our study were male sex (72.1%), cesarean section mode of delivery (54.2%), positive pressure ventilation while resuscitation (44.2%) birth asphyxia (40.4%) and meconium aspiration syndrome (MAS)35.4%. It was found that male sex (88.8%), cesarean-section delivery (77.7%), respiratory distress syndrome (RDS) 44.8% and sepsis (44.4%) were more associated with PPHN in premature infants than with term and post term infants. Out of the total 79 patients, death occurred among 7 preterm and 14 terms and post term infants. As a whole, cesarean section mode of delivery (71.4%), birth asphyxia (57.1%) and female sex (52.4%) were found major risk factors associated with mortality. However, respiratory distress syndrome (Relative Risk RR=5), birth asphyxia (RR=2.5) and male sex (RR=2)were found to be associated with increased risk of mortality in preterm than term and post term infants.

Conclusion: Male gender, cesarean section mode of delivery, MAS and RDS are the major risk factors for PPHN in any age group. RDS, Birth asphyxia and male sex are associated with increased risk of mortality in pre term than term and post term infants.