Patent ductus arteriosus and its treatment as risk factors for neonatal and neurodevelopmental morbidity

Perinatal and neonatal risk factors for retinopathy of prematurity in very low birthweight, very preterm twins: a population-based study

OBJECTIVE

To determine the effect of perinatal and neonatal risk factors on retinopathy of prematurity (ROP) and to examine the association of fertility treatments on the risk for ROP in very low birth weight (VLBW) preterm twins.

METHODS

The population-based observational study consisted of VLBW twins born at 24-29 weeks gestational age (GA). Data from the Israel national database (1995-2020) were applied. Univariate and multivariable logistic regression using the General Estimating Equation were used for assessment of risk factors.

RESULTS

The study population comprised 4092 infants of whom 2374 (58%) were conceived following fertility treatments. ROP was diagnosed in 851 (20.8%) infants. The odds for ROP approximately doubled with each week decrease in GA: at 24 weeks, Odds Ratio (OR) 58.00 (95% confidence interval (CI) 31.83-105.68); 25 weeks, OR 25.88 (95% CI 16.76-39.96); 26 weeks, OR 12.69 (95% CI 8.84-18.22) compared to 29 weeks GA. Each decrease in one birthweight z-score was associated with 1.82-fold increased risk for ROP (OR, 1.82, 95% CI 1.59-2.08). Infertility treatments were not associated with ROP. Neonatal morbidities significantly associated with ROP were surgical necrotizing enterocolitis (NEC) (OR, 2.04, 95% CI 1.31-3.19); surgically treated patent ductus arteriosus (PDA) (OR, 1.63, 95% CI 1.12-2.37); sepsis (OR, 1.43, 95% CI 1.20-1.71) and bronchopulmonary dysplasia (OR, 1.52, 95% CI 1.22-1.90).

CONCLUSION

Among preterm VLBW twins, poor intrauterine growth and surgical interventions for NEC and PDA were associated with high odds for ROP. This study does not support an association of fertility treatments with increased risk for ROP.

Should we "eliminate" PDA shunt in preterm infants? A narrative review

The patent ductus arteriosus frequently poses a significant morbidity in preterm infants, subjecting their immature pulmonary vascular bed to substantial volume overload. This, in turn, results in concurrent hypoperfusion to post-ductal organs, and subsequently alters cerebral blood flow. In addition, treatment has not demonstrated definitive improvements in patient outcomes. Currently, the optimal approach remains a subject of considerable debate with ongoing research controversy regarding the best approach. This article provides a comprehensive review of existing literature.

Transcatheter closure of patent ductus arteriosus in preterm infants: results from a single-center cohort

Objective

To assess the success rate of patent ductus arteriosus (PDA) transcatheter closure in preterm infants and to describe the nature of procedural adverse events and short-term clinical status.

Study design

All the preterm infants with PDA transcatheter closure were evaluated retrospectively between July 2019 and March 2023 in a single level III neonatal intensive care unit in France. The procedure was performed in the catheterization laboratory using venous canulation. We retrospectively collected data about the patients' characteristics, procedural outcomes and complications.

Results

Twenty-five infants born between 23.4 and 32.0 weeks of gestational age (mean ± SD 26.3 ± 1.9 weeks) underwent transcatheter PDA closure. Their mean age and weight at the time of the procedure were 52 days (range 22-146 days) and 1,620 g (range 890-3,700 g), respectively. Successful closure was achieved in all but one patient. Procedure related complications were reported in 10 infants (40%), including 6 left pulmonary artery stenosis one of which required a balloon dilatation, two cardiac tamponades and two inferior vena cava thrombosis. Only two post-ligature syndromes occurred after the procedure. Two infants died one of which was related to the procedure.

Conclusion

Transcatheter closure of a PDA is a valid alternative to surgical ligation due to its high success rate and low incidence of post-ligature syndrome. Nevertheless, we also report rare, although serious complications.

Bedside Cerebral Blood Flow Quantification in Neonates

Measurement of blood flow to the brain in neonates would be a very valuable addition to the medical diagnostic armamentarium. Such conditions such as assessment of closure of a patent ductus arteriosus (PDA) would greatly benefit from such an evaluation. However, measurement of cerebral blood flow in a clinical setting has proven very difficult and, as such, is rarely employed. Present techniques are often cumbersome, difficult to perform and potentially dangerous for very low birth weight (VLBW) infants. We have been developing an ultrasound blood volume flow technique that could be routinely used to assess blood flow to the brain in neonates. By scanning through the anterior fontanelles of 10 normal, full-term newborn infants, we were able to estimate total brain blood flows that closely match those published in the literature using much more invasive and technically demanding methods. Our method is safe, easy to do, does not require contrast agents and can be performed in the baby's incubator. The method has the potential for monitoring and assessing blood flows to the brain and could be used to routinely assess cerebral blood flow in many different clinical conditions.

Patent Ductus Arteriosus: A Contemporary Perspective for the Pediatric and Adult Cardiac Care Provider

The burden of patent ductus arteriosus (PDA) continues to be significant. In view of marked differences in preterm infants versus more mature, term counterparts (viewed on a continuum with adolescent and adult patients), mechanisms regulating ductal patency, genetic contributions, clinical consequences, and diagnostic and treatment thresholds are discussed separately, when appropriate. Among both preterm infants and older children and adults, a range of hemodynamic profiles highlighting the markedly variable consequences of the PDA are provided. In most contemporary settings, transcatheter closure is preferable over surgical ligation, but data on longer-term outcomes, particularly among preterm infants, are lacking. The present review provides recommendations to identify gaps in PDA diagnosis, management, and treatment on which subsequent research can be developed. Ultimately, the combination of refined diagnostic thresholds and expanded treatment options provides the best opportunities to address the burden of PDA. Although fundamental gaps remain unanswered, the present review provides pediatric and adult cardiac care providers with a contemporary framework in PDA care to support the practice of evidence-based medicine.

Is early patent ductus arteriosus ligation helpful in premature neonates? A 10-year retrospective study

BACKGROUND

To compare short and long outcomes between early (≤ 28 days) (EL) and late ligation (LL) groups. To explore factors predicting early extubation (≤ 7 days) after patent ductus arteriosus (PDA) ligation.

METHODS

We conducted a single center, retrospective cohort study of preterm infants < 32 weeks who underwent surgical ligation over a 10-year period (2009-2019).

RESULTS

A total of 133 infants underwent PDA ligation, in the study period. Both groups had similar short-term outcome such as bronchopulmonary dysplasia (BPD) or death (96% vs. 98%, P = 0.64) and long-term clinical outcomes including Bayley's assessment at 2 years corrected age. Fewer infants in the EL group developed severe BPD (63% vs. 81%, P = 0.02). Age at ligation had adjusted odds ratio of 1.04 with over lapping confidence interval (95% CI 1.0-1.1, P = 0.02) for severe BPD/death. There was no difference in day of extubation between the EL and LL group (8 days vs. 7 days, P = 0.85). Left atrium/aortic root ratio of ≥ 1.75 would give sensitivity of 41% and 80% specificity for early extubation (area under the curve of 0.61). There was marginal reduction of hospital stay in the EL group [113 (105-121) days vs. 115 (107-123) days; log rank P = 0.026].

CONCLUSION

EL can be delivered safely with a clinically important lower incidence of severe BPD and shorter duration of hospital stay compared to LL.

Brain and renal oxygenation measured by NIRS related to patent ductus arteriosus in preterm infants: a prospective observational study

Background

Patent ductus arteriosus (PDA) is common among preterm neonates. Haemodynamically significant ductus arteriosus (hsPDA) can cause ductal steal and contribute to poor outcomes. Our aim was to evaluate ductus arteriosus patency and significance using two-site near-infrared spectroscopy (NIRS) measurements in preterm infants older than 72 h as a supplemental tool to echocardiography.

Methods

In this prospective observational study, 123 preterm infants (gestational age (GA) < 32 weeks, birth weight < 1500 g) were enrolled. Sixty-four newborns had closed ductus arteriosus (noPDA), and 41 and 18 patients were assigned to the PDA and hsPDA groups, respectively, per predefined echocardiographic criteria. Cerebral and renal oxygenation were assessed during NIRS monitoring.

Results

A higher renal mean (±SD) regional tissue oxygen saturation (rSpO₂) (76.7 (±7.64)) was detected in the noPDA group than in the PDA (71.7 (±9.02)) and hsPDA (67.4 (±13.48)) groups (p < 0.001). Renal fractional tissue oxygen extraction (FTOE) (0.18 (±0.079)) was lower in the noPDA group than in the PDA (0.23 (±0.092)) and hsPDA (0.24 (±0.117))0.117 groups (p = 0.002). Cerebral oxygenation was significantly lower in the hsPDA group (77.0 (±5.16)) than in the noPDA (79.3 (±2.45)) and PDA (79.7 (±2.27)) groups (p = 0.004). There was no significant difference in cerebral fractional tissue oxygen extraction (FTOE) between any of the groups.

Conclusions

Our results suggest that renal oxygenation is affected by ductus patency in preterm infants older than 72 h. Significant differences in cerebral oxygenation were observed between the hsPDA group and the PDA and noPDA groups.

Trial registration

ClinicalTrials.gov Identifier: NCT04295395. Registration date: 4 March 2020. This study was retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04295395.

Near-infrared spectroscopy for perioperative assessment and neonatal interventions

Perioperative applications of near-infrared spectroscopy (NIRS) to monitor regional tissue oxygenation and perfusion in cardiac and noncardiac surgery are of increasing interest in neonatal care. Complex neonatal surgery can impair adequate oxygen delivery and tissue oxygen consumption and increase the risk of neurodevelopmental delay. Coupled with conventional techniques, NIRS monitoring may enable targeted hemodynamic management of the circulation in both cardiac and noncardiac surgical procedures. In this narrative review, we discuss the application of perioperative NIRS in specific neonatal interventions, including surgical intervention for congenital heart defects, definitive closure of the patent ductus arteriosus, neurological and gastrointestinal disorders, and use of extracorporeal membrane oxygenation. We identified areas for future research within disease-specific indications and offer a roadmap to aid in developing evidence-based targeted diagnostic and management strategies in neonates. IMPACT: There is growing recognition that perioperative NIRS monitoring, used in conjunction with conventional monitoring, may provide critical hemodynamic information that either complements clinical impressions or delivers novel physiologic insight into the neonatal circulatory and perfusion pathways.

Retrospective comparison of death or neurodevelopmental outcomes in extremely low birth weight preterm infants following different management options of haemodynamically significant patent ductus arteriosus

BACKGROUND

Optimal management of haemodynamically significant patent ductus arteriosus (HsPDA) in premature babies remains controversial. Our aim is to compare death and/or adverse neurodevelopmental outcomes in extremely low birth weight (ELBW) infants with HsPDA who were managed with conservative [C], medical [M] and/or surgical [S] treatment, with secondary aim to examine short-term morbidities among [S] and [C] groups. The study also compared outcomes in very low birth weight (VLBW) infants with HsPDA and non-HsPDA.

METHODS

A retrospective study of VLBW preterm infants born before 29 weeks in Singapore from 2007 to 2016 was conducted.

RESULTS

A total of 474 VLBW infants were admitted in NUH from 2007 to 2016. Infants aged between 24 + 0 and 28 + 6 weeks of gestation, weighing ≤1500 g and diagnosed with patent ductus arteriosus (PDA) were included in the study, of which 172 infants (124 HsPDA and 48 non-HsPDA) were analyzed. Among infants with HsPDA, 17 infants were managed with [C], 83 with [M] and 24 with [S]. Mortality was not increased regardless of the presence of HsPDA or treatment received. Infants with non-HsPDA were less likely to have isolated speech delay (p < 0.05), but not global developmental delay (GDD). No significant differences in neurodevelopmental outcomes such as hearing loss, cerebral palsy (CP) and speech delay were found. [M + S] infants were at a higher risk of developing chronic lung disease (CLD) (OR 6.83, p < 0.05) and short-term growth failure compared to [C] infants. They were significantly shorter and had a smaller head circumference at discharge (p < 0.05). [M + S] infants also had elevated creatinine compared to those in group [C] (81.1 ± 24.1 vs 48.3 ± 11.8 umol/L, p < 0.000).

CONCLUSIONS

Compared to conservative management, infants requiring [M + S] treatment for HsPDA were more likely to have short-term complications such as CLD, elevated creatinine, and poorer growth. Despite a more turbulent postnatal course, death and/or adverse neurodevelopmental outcomes were not worse in infants managed with [M + S].

Surgical management of patent ductus arteriosus in pre-term infants - a british paediatric surveillance study

BACKGROUND

This study aimed to provide UK data describing the incidence of patent ductus arteriosus (PDA) surgery in the neonatal population, including: pre-ligation management, and outcomes until discharge. We used British Paediatric Surveillance Unit (BPSU) methodology; collecting data via questionnaires for preterm neonates undergoing PDA ligation (PDAL) between 1st Sept 2012 - 30th Sept 2013. Infants born less than 37 weeks gestation, who underwent PDAL prior to discharge home, with no other structural cardiac abnormality, were included. Information collected included: patient demographics, pre and post-operative clinical characteristics, pre-operative medical management, post-operative complications and outcome.

RESULTS

Over the study, 263 infants underwent PDAL an incidence of 3.07 per 10,000 live births. 88% were born extremely preterm (< 28 weeks) and 60% were male. The commonest reasons for ligation were inability to wean respiratory support (83.7%) and haemodynamically significant PDA (87.8%). Pre-operatively 65.7% received medical therapy. Surgery was performed at a median age of 33 days (range 9-260, IQR 24-48); the corrected age was less than 31 + 6 week in 50.6% babies at PDAL. Most, (90%), of procedures were open ligation; only 9 (3.4%) were catheter occlusions (PDACO). 20.5% of patients had post-operative complications. The 30-day mortality was 3%, with 93.5% surviving to hospital discharge.

CONCLUSION

This study showed there was little consensus over medical and surgical management of the PDA or timing of surgery.

Oral Versus Intravenous Medications for Treatment of Patent Ductus Arteriosus in Preterm Neonates: A Cost-Saving Initiative

OBJECTIVE

The purpose of the study was to quantify cost savings after promoting oral pharmacotherapy for the treatment of hemodynamically significant patent ductus arteriosus (hsPDA).

METHODS

This was a retrospective before-and-after time series quality improvement study. Oral ibuprofen and acetaminophen use criteria were developed and recommended, rather than the more costly intravenous equivalents. There were 24-month medication use reports generated for both the pre-criteria (Era-1) and the post-criteria (Era-2) implementation phases to identify neonates prescribed hsPDA medications in order to assess cost differences.

RESULTS

Era-1 had 190 treatment courses in 110 neonates for a total medication cost of $171,260.70. Era-2 had 210 courses in 109 patients for a total medication cost of $47,461.49, yielding savings of $123,799.21 ($61,899.61 annually) after criteria implementation. The reduction in intravenous ibuprofen use in Era-2 accounted for all the savings.

CONCLUSION

Preferentially prescribing lower-cost oral medications to treat hsPDA led to significant cost savings.

The type and timing of patent ductus arteriosus treatment was associated with neurodevelopment when extremely preterm infants reached 6.5 years

AIM

This study investigated patent ductus arteriosus (PDA) treatment and neurodevelopmental outcomes when extremely preterm born children reached 6.5 years.

METHOD

Our cohort was 435 children with neonatal PDA treatment data and neurodevelopmental follow-up data, born in 2004-2007, who participated in the Extremely Preterm Infants in Sweden Study. Pharmacological or surgical PDA treatment and the age at PDA treatment, were investigated in relation to the risks of moderate to severe neurodevelopmental impairment (NDI) and full-scale intelligence quotient (FSIQ) at 6.5 years.

RESULTS

The children who received PDA drug treatment, including those who also had surgery, had the same risk of moderate to severe NDI or lower FSIQ as untreated children. However, children who had primary PDA surgery faced increased risks of NDI, with an adjusted incidence rate ratio of 1.62 (95% confidence interval [CI] 1.28-2.06) and a lower adjusted mean difference FSIQ of -7.1 (95% CI -11 to -3.2). Surgery at less than 10 days of life was associated with a significantly increased risk of moderate to severe NDI and lower FSIQ than surgery after 20 days.

CONCLUSION

Drug treatment followed by deferred surgery appeared to be a safer option for extremely preterm infants severely affected by PDA.

Factors affecting the effectiveness of oral ibuprofen in the treatment of patent ductus arteriosus in preterm infants

Background Data on the effectiveness of oral ibuprofen treatment for patent ductus arteriosus are limited, and the factors affecting its effectiveness remain unclear. Objective The aim was to identify the potential factors affecting the clinical effectiveness of oral ibuprofen in preterm infants. Setting Neonatal intensive care unit in a prefecture-level maternal and child healthcare hospital in China. Method Over a 5-years period, the medical records of 327 preterm infants with patent ductus arteriosus who were admitted to the neonatal intensive care unit of our hospital to receive a single course of oral ibuprofen were retrospectively reviewed. Main outcome measures The prevalence of risk factors affecting the effectiveness of oral ibuprofen. Results In total, 201 (61.47%) preterm infants were considered to have undergone "effective therapy" and classified accordingly, whereas 11 (3.36%) showed certain adverse events. Factors affecting therapeutic effectiveness were postnatal age at the initiation of treatment and Day 1/Day 0 ratio of urine output/fluid intake during the treatment course, with odds ratios of 0.892 (95% CI: 0.835-0.953; P = 0.001) and 0.473 (95% CI 0.265-0.845; P = 0.011), respectively. Conclusion A single course of oral ibuprofen for patent ductus arteriosus closure among preterm infants is effective and safe. Preterm infants with postnatal age of ≤ 9 days at the initiation of treatment and Day 1/Day 0 ratio of ≤ 0.708 of the urine output/fluid intake during the treatment course can be considered predictors of effectiveness of patent ductus arteriosus.

Left Vocal Cord Paralysis, Lung Function and Exercise Capacity in Young Adults Born Extremely Preterm With a History of Neonatal Patent Ductus Arteriosus Surgery-A National Cohort Study

Background: Left vocal cord paralysis (LVCP) is a known complication of patent ductus arteriosus (PDA) surgery in extremely preterm (EP) born neonates; however, consequences of LVCP beyond the first year of life are insufficiently described. Both voice problems and breathing difficulties during physical activity could be expected with an impaired laryngeal inlet. More knowledge may improve the follow-up of EP-born subjects who underwent PDA surgery and prevent confusion between LVCP and other diagnoses. Objectives: Examine the prevalence of LVCP in a nationwide cohort of adults born EP with a history of PDA surgery, and compare symptoms, lung function, and exercise capacity between groups with and without LVCP, and vs. controls born EP and at term. Methods: Adults born EP (<28 weeks' gestation or birth weight <1,000 g) in Norway during 1999-2000 who underwent neonatal PDA surgery and controls born EP and at term were invited to complete questionnaires mapping voice-and respiratory symptoms, and to perform spirometry and maximal treadmill exercise testing. In the PDA-surgery group, exercise tests were performed with a laryngoscope positioned to evaluate laryngeal function. Results: Thirty out of 48 (63%) eligible PDA-surgery subjects were examined at mean (standard deviation) age 19.4 (0.8) years, sixteen (53%) had LVCP. LVCP was associated with self-reported voice symptoms and laryngeal obstruction during exercise, not with lung function or peak oxygen consumption (VO₂peak). In the PDA-surgery group, forced expiratory volume in 1 second z-score (z-FEV₁) was reduced compared to EP-born controls (n = 30) and term-born controls (n = 36); mean (95% confidence interval) z-FEV₁ was -1.8 (-2.3, -1.2), -0.7 (-1.1, -0.3) and -0.3 (-0.5, -0.0), respectively. For VO₂peak, corresponding figures were 37.5 (34.9, 40.2), 38.1 (35.1, 41.1), and 43.6 (41.0, 46.5) ml/kg/min, respectively. Conclusions: LVCP was common in EP-born young adults who had undergone neonatal PDA surgery. Within the PDA-surgery group, LVCP was associated with self-reported voice symptoms and laryngeal obstruction during exercise, however we did not find an association with lung function or exercise capacity. Overall, the PDA-surgery group had reduced lung function compared to EP-born and term-born controls, whereas exercise capacity was similarly reduced for both the PDA-surgery and EP-born control groups when compared to term-born controls.

Hemodynamic and clinical consequences of early versus delayed closure of patent ductus arteriosus in extremely low birth weight infants

OBJECTIVES

To describe changes in hemodynamics, respiratory support, and growth associated with transcatheter PDA closure (TCPC) in ELBW infants, stratified by postnatal age at treatment.

STUDY DESIGN

This is an observational study of ELBW infants who underwent TCPC at ≤4 weeks (Group-1; n = 34), 4-8 weeks (Group-2; n = 33), and >8 weeks of age (Group-3; n = 33). Hemodynamic assessment was performed during TCPC. Multivariate Cox-proportionate-hazard modeling was used to identify factors associated with respiratory severity score (RSS) > 2 for >30 days following TCPC.

RESULTS

In comparison with Group-1, Group-3 infants had higher pulmonary vascular resistance (PVRi = 3.3 vs. 1.6 WU*m²; P = 0.01), less weight gain between 4 and 8 weeks of age (16 vs. 25 g/day) and took longer to achieve RSS < 2 (median 81 vs. 20 days; P = 0.001). RSS > 2 for >30 days was associated with TCPC > 8 weeks (OR = 3.2, 95% CI: 1.75-5.8; p = 0.03) and PVRi ≥ 3 (OR = 4.5, 95% CI: 2.7-8.9; p < 0.01).

CONCLUSION

ELBW infants may benefit from PDA closure within the first 4 weeks of life in order to prevent early onset pulmonary vascular disease, promote faster growth, and for quicker weaning of ventilator and oxygen support.

Next Generation Sequencing Identify Rare Copy Number Variants in Non-syndromic Patent Ductus Arteriosus

Patent ductus arteriosus (PDA) is a common congenital cardiovascular malformation with both inherited and acquired causes. Several genes have been reported to be related to PDA, but the molecular pathogenesis is still unclear. Here, we screened a population matched cohort of 39 patients with PDA and 100 healthy children using whole exome sequencing (WES). And identified 10 copy number variants (CNVs) and 20 candidate genes using Gene ontology (GO) functional enrichment analysis. In gene network analysis, we screened 7 pathogenic CNVs of 10 candidate genes (MAP3K1, MYC, VAV2, WDR5, RXRA, APLNR, TJP1, ERCC2, FOSB, CHRNA4). Further analysis of transcriptome array showed that 7 candidate genes (MAP3K1, MYC, VAV2, APLNR, TJP1, FOSB, CHRNA4) were indeed significantly expressed in human embryonic heart. Moreover, CHRNA4 was observed the most important genes. Our data provided rare CNVs as potential genetic cause of PDA in humans and also advance understanding of the genetic components of PDA.

Surgical ligation of patent ductus arteriosus in preterm neonates weighing less than 1500g: a 9-year single center experience

BACKGROUND

The aim of this study was to determine the feasibility and outcomes of early surgical ligation in preterm neonates with hemodynamically significant patent ductus arteriosus (HSPDA) and to investigate predictors for surgical treatment after unsuccessful medical management.

METHODS

Medical records from the neonatal intensive care unit of Hanyang University Seoul Hospital from January 2010 to December 2018 were retrospectively reviewed. 233 preterm neonates weighing less than 1500g with HSPDA were enrolled in our study. Of these preterm neonates, 134 underwent surgical ligation and were subdivided into the early ligation group (n = 49; within 10 days of age) and the late ligation group (n = 85; after 10 days of age).

RESULTS

The mean gestational age and birth weight were significantly lower in the patent ductus arteriosus (PDA) ligation group than in the Non-ligation group (p <  0.001). PDA ductal diameter > 2.0 mm (p <  0.001), low Apgar score at 5 min (p = 0.033), and chorioamnionitis (p = 0.037) were the predictors for receiving surgical treatment for PDA. Early ligation was significantly associated with a low incidence of culture-proven sepsis (p = 0.004), mechanical ventilator time > 4 weeks (p = 0.007), necrotizing enterocolitis stage (NEC) ≥ III (p = 0.022), and intraventricular hemorrhage (IVH) grade ≥ III (p = 0.035).

CONCLUSIONS

Early surgical ligation minimizes the adverse effects of HSPDA in predicted preterm neonates who subsequently require surgical treatment for PDA. This result suggests that in preterm neonates weighing less than 1500g with HSPDA that is unresponsive to medical treatment, delayed ductal closure should be avoided to reduce severe NEC, severe IVH, culture-proven sepsis, and facilitate earlier endotracheal extubation.

Therapeutic strategy of patent ductus arteriosus in extremely preterm infants

The ductus arteriosus is likely to close without treatment in most infants born at gestational age (GA) > 28 weeks (73%), and those with birth weight > 1000 g (94%). However, the rates of spontaneous ductal closure among less mature or smaller infants with respiratory distress syndrome are not known. Extremely preterm infants born at GA < 28 weeks are associated with a high risk of severe intraventricular hemorrhage (IVH) or pulmonary hemorrhage, which usually occur within 72 h after birth and affect mortality and long-term neurological development. These serious hemorrhagic complications may be closely related to hemodynamic changes caused by a hemodynamically significant patent ductus arteriosus (hs-PDA). While prophylactic indomethacin has been shown to reduce the rates of PDA, PDA ligation, severe IVH and early pulmonary hemorrhage, the available evidence does not support its prophylactic use in preterm infants. Symptomatic or late treatment is associated with lower success rate, and increased complications of a hs-PDA. The issue of "to treat or not to treat a PDA" is controversial. Considering the relationship between the effectiveness and timing of pharmacological treatment, early targeted treatment may be an alternative approach for the early identification of a hs-PDA in specific high-risk patient population, especially infants <26 weeks GA who are at the highest risk of severe IVH or pulmonary hemorrhage. Serial echocardiographic studies can be used to select patients who are candidates for early targeted medical treatment of hs-PDA. Surgical ligation of PDA, and transcatheter closure if proven to be safe, can be used as back-up therapy for patients who fail medical treatment and continue to have cardiopulmonary compromise.

Prediction of Bronchopulmonary Dysplasia in Preterm Infants Using Postnatal Risk Factors

Objective: To identify postnatal risk factors for bronchopulmonary dysplasia (BPD) development in preterm infants with gestational age ≤32 weeks. Methods: Seventy-two preterm infants(30 with BPD and 42 non-BPD controls) admitted in the neonatal intensive care unit (NICU) of the Children's Hospital of Soochow University during 2017 were enrolled in this prospective longitudinal study. Perinatal clinical data, a neonatal critical illness score (NCIS), different soluble B7-H3(sB7-H3), and interleukin-18 (IL-18) levels by days after birth were collected. An early predictive model for BPD development was established based on clinical data using multiple logistic regression analysis. And the sensitivity and specificity of the model were assesed by ROC curve. Results: Electrolyte disturbances, hemodynamically significant patent ductus arteriosus (hs-PDA), and the age that infants achieved 120 kcal/kg.d via enteral feeding ≥40 days after birth were found to be associated with the BPD pathogenesis. Serum sB7-H3, IL-18, and NCIS were significantly higher in the BPD group compared to the non-BPD group (p < 0.05). BPD group had significantly lower enteral fluid and caloric intake compared to the non-BPD group at 1, 7, 14, and 28 days after birth. The risk factors were analyzed by multiple logistic regression and a predictive model of a combination of sB7-H3 (day 7), IL-18 (day 14), NCIS, and clinical risk factors was evaluated via ROC curve with an area under the curve (AUC) of 0.960 having sensitivity of 86.7% and a specificity of 97.6%, respectively. Conclusion: The causes of BPD are multifactorial postnatal risk factors. And the combination of sB7-H3 (day 7), IL-18 (day 14), NCIS, and clinical risk factors (electrolyte disturbances, hs-PDA, and the age that infants achieved 120 kcal/kg.d via enteral feeding ≥40 days after birth) might be served as an optimal predictive model for the occurrence of BPD.

Conservative Non-intervention Approach for Hemodynamically Significant Patent Ductus Arteriosus in Extremely Preterm Infants

While persistent patent ductus arteriosus (PDA) in preterm infants has been known to be associated with increased mortality and morbidities including bronchopulmonary dysplasia, and necrotizing enterocolitis, there is minimal evidence supporting their causal relationships, and most traditional medical and/or surgical treatments have failed to show improvements in these outcomes. As such, the pendulum has swung toward the conservative non-intervention approach for the management of persistent PDA during the last decade; however, the benefits and risks of this approach are unclear. In this mini review, we focused on whom, when, and how to apply the conservative non-intervention approach for persistent PDA, especially in extremely preterm infants.

Transcatheter Closure of Patent Ductus Arteriosus in Infants With Weight Under 1,500 Grams

Persistent patent ductus arteriosus (PDA) is very common in preterm infants, especially in extremely preterm infants. Despite significant advances in management of these vulnerable infants, there has been no consensus on management of PDA-when should we treat, who should we treat, how should we treat and in fact there is no agreement on how we should define a hemodynamically significant PDA. Medical management with non-steroidal anti-inflammatory drugs (NSAIDs) remains the first line of therapy with moderate success rate in closing the PDA. Paracetamol has been reported to be a safe and equally effective medical therapy for closure of PDA. However, additional studies on its long-term safety and efficacy in extremely low birth weight infants are needed before paracetamol can be recommended as standard treatment for a PDA in preterm infants. Surgical ligation of PDA is not without an increased risk of mortality and co-morbidities. Recently, there has been a significant interest in percutaneous transcatheter closure of PDA in preterm infants, including extremely low birth weight infants. Transcatheter PDA closure in preterm ELBW infants is technically feasible with high PDA occlusion success rates and acceptable complication rates as compared to surgical ligation. Many centers have reported promising early- and mid-term follow-up results. However, they need to be further tested in the prospective well-designed studies and randomized controlled trials comparing the results and outcomes of this technique with current treatment strategies including medical treatment before they can be used as the new standard of care for PDA closure in extremely low birth weight infants.

Safety of Conservative Approach for Persistent Patent Ductus Arteriosus in Preterm Infants: Neurodevelopmental Outcomes at 5 Years of Age

Patent ductus arteriosus (PDA) is a common problem among preterm infants. The standard of care for PDA has been to attempt to close the PDA by pharmacological treatment or surgical ligation. Recently, conservative approach for PDA (i.e., infants receive no treatment for PDA unless it is necessary for rescue) is gaining interest. However, when PDA is persisted under the conservative approach, there is a concern about the neurodevelopmental problems caused by decreased cerebral oxygenation. Our objective was to examine the risk of neurodevelopmental impairment in preterm infants, when PDA remained persistently open under conservative approach for PDA. We retrospectively analyzed data from the medical charts in 72 included infants (gestational age < 29 weeks, birth weight < 1,250 g). Under our conservative approach for PDA, we divided infants by their ductal patency: a closed ductus group (ductus closure within 14 days after birth, n = 52) and a persistent patent ductus arteriosus group (ductus closure after 14 days, n = 20). We compared the clinical parameters and neurodevelopmental outcomes assessed with the Kaufman Assessment Battery for Children (K-ABC) at 5 years of corrected age in two groups. Among the children who completed the K-ABC test, there were no significant differences in neurodevelopmental scores between a closed ductus group (n = 44) and a persistent patent ductus arteriosus group (n = 17). A conservative approach for PDA, even in the case of prolonged PDA, does not increase the risk of neurodevelopmental impairment at 5 years of corrected age in preterm infants.

Effects of Executive Function Training on Attentional, Behavioral and Emotional Functioning and Self-Perceived Competence in Very Preterm Children: A Randomized Controlled Trial

OBJECTIVE

Very preterm children have poorer attentional, behavioral and emotional functioning than term-born children. Problems on these domains have been linked to poorer executive function (EF). This study examined effects of a game-formatted, comprehensive EF training on attentional, behavioral and emotional functioning and self-perceived competence in very preterm children.

STUDY DESIGN

Eighty-five children participated in a multi-center, double-blind, placebo and waitlist-controlled randomized trial. Children were recruited from neonatal follow-up units of two academic medical centers in The Netherlands. Eligible for inclusion were 8-12 year old children born very preterm (<30 weeks of gestation) and/or with extremely low birthweight (<1000 g) with parent reported attention problems. Children were randomly assigned to one of three treatment arms: EF training, placebo training or waitlist. The EF and placebo training involved a 6 weeks, 25 (30-45 min) sessions training program. Attentional functioning (Attention Network Test), behavioral and emotional functioning (parent and teacher Strengths and Difficulties questionnaire) and self-perceived competence (Self-Perception Profile for Children) were assessed at baseline, at the end of the training program and 5 months after the training was finished. Data analyses involved linear mixed model analyses.

RESULTS

Children in the EF training arm significantly improved on all training tasks over the course of the EF training program. Despite these improvements on the EF training tasks, there were no significant differences over time on any of the outcome measures between the three treatment arms, indicating that this computerized EF training program had no beneficial effects.

CONCLUSION

Although there were significant improvements in the EF training tasks, there was no generalization of these improvements to any of the outcome measures. Thus, our findings do not support the use of computerized EF training programs. Future research should investigate effectivity of more ecologically valid, real-world like EF training programs.

The association between NIRS and Doppler ultrasonography in preterm infants with patent ductus arteriosus

Objective: To determine if near-infrared spectroscopy (NIRS), which is easier to obtain than Doppler ultrasonography (USG), may be used in accordance with Doppler USG to provide additional data for assessment of organ blood flow velocities in preterm infants with hemodynamically significant PDA.Study design: Thirty-one infants who were treated with ibuprofen for closure of PDA were monitored continuously with NIRS. Cerebral, mesenteric, and renal arterial blood flow velocities were measured with Doppler USG before and after the treatment.Results: While cerebral, mesenteric, and renal fractional oxygen extraction (FTOE) measurements decreased significantly (p = .042, p < .001, p < .001, respectively), NIRS measurements (p = .016, p < .001, p < .001, respectively) and mean blood flow velocities (p = .003, p = .011, p = .002, respectively) increased significantly after the treatment. There was a significant correlation between pretreatment cerebral and mesenteric FTOE and resistive index (RI) values (r = 0.45, p = .01, and r = 0.46, p = .01, respectively). However, no correlation was observed between renal FTOE values and renal RI (r = 0.33, p = .06). Posttreatment cerebral, renal, and mesenteric FTOE values correlated positively with corresponding RI (r = 0.41, p = .02; r = 0.39, p = .02; r = 0.65, p < 01; respectively). Pretreatment and posttreatment cerebral, mesenteric, and renal FTOE values and arterial mean velocities were inversely correlated (pretreatment: r = 0.69, p < .01; r = 0.72, p < .01; r = 0.77, p < .01; posttreatment: r = 0.54, p = .01; r = 0.69, p < .01; r = 0.38, p = .01; respectively).Conclusion: As Doppler and NIRS measurements correlated significantly, we concluded that NIRS might be used in monitoring organ blood flow in preterm infants with PDA, which may provide additional data for management of this condition.

Birth weight, Apgar scores and gentamicin were associated with acute kidney injuries in VLBW neonates requiring treatment for patent ductus arteriosus

AIM

We assessed the risk factors for transient acute kidney injury in very low birth weight (VLBW) infants treated for patent ductus arteriosus (PDA) using the serum creatinine-based criteria in Kidney Disease: Improving Global Outcomes.

METHOD

This retrospective study of infants requiring ibuprofen and, or, surgery for haemodynamic relevant PDAs was performed at the University Children's Hospital of Saarland, Homburg, Germany, from January 2009 to December 2015.

RESULTS

We studied 422 infants with a mean birth weight of 1059 ± 308.2 g. Acute kidney injuries developed in 150/295 infants (50.9%) with spontaneous PDA closure, in 46/82 (56.1%) who received intravenous ibuprofen treatment, in 18/24 (75.0%) who had surgery and in 15/21 infants (71.4%) who received both medical and surgical treatment. Acute kidney injuries were associated with birth weight and gestational age, Apgar scores at 10 minutes, the PDA size corrected for birth weight, a PDA with three affected circulatory territories, PDA surgery and gentamicin. Multiple logistic regression analysis showed particular associations between acute kidney injury and birth weight (p = 0.001), the 10-minute Apgar score (p = 0.02) and gentamicin (p = 0.043).

CONCLUSION

Birth weight, the 10-minute Apgar score and gentamicin were particularly associated with acute kidney injuries in our cohort.

Monitoring and management of brain hemodynamics and oxygenation

While cardiorespiratory monitoring is standard for newborns in the NICU, monitoring of brain hemodynamics and oxygenation is usually sporadic and targeted to newborns with suspected or confirmed neurologic disorders. This is unfortunate, since critically ill newborns, both preterm and term-born, are at high risk of brain injury and would benefit from improved techniques for continuous monitoring of brain hemodynamics and oxygenation, in addition to monitoring of systemic hemodynamics and oxygenation. Near-infrared spectroscopy (NIRS) and, to a lesser extent, Doppler ultrasound are techniques that have been used in research and increasingly for clinical purposes to measure and monitor brain hemodynamics and oxygenation in newborns. NIRS monitoring can be useful for detection of diverse pathologic conditions that occur frequently in very preterm newborns and in selected populations of term newborns at risk for brain injury related to disturbances of systemic hemodynamics. This chapter reviews the current state of the art with regard to brain-monitoring techniques and the research directed at this important area, and it concludes with suggestions for the use of currently available tools to manage newborns at high risk of neurologic injury from disturbances in brain hemodynamics and oxygenation.

Pharmacotherapy for patent ductus arteriosus closure

Even though up to 60% of premature infants less than 28 weeks gestation develop persistent patent ductus arteriosus (PDA), there remains controversy regarding if, when, and how to close the PDA. Failure to close the PDA has been associated with significant morbidity but no cause-and-effect has been proven for short-term or long-term outcomes in modern times. Surgical closure has the advantage of eliminating the PDA, but short-term complications and long-term adverse outcomes are worrisome. Intravenous indomethacin has been the "gold standard" for pharmacologic treatment over the past 40 years with high closure rates and decreased incidence of severe intraventricular hemorrhage (IVH) and pulmonary hemorrhage with early treatment but without improvement in long-term outcomes and with risk of renal toxicity. Intravenous ibuprofen has less vasoconstrictive toxicity than indomethacin with comparable closure rates but without improvement in IVH and with hyperbilirubinemia risks. Earlier this decade, acetaminophen (paracetamol) was discovered to effectively close the PDA with good short-term safety profile. Although promising, acetaminophen treatment requires further studies regarding long-term safety as well as ideal dosing and route of administration.

Bronchopulmonary dysplasia: Pathogenesis and treatment

Bronchopulmonary dysplasia (BPD) is a form of chronic lung disease of infancy, which mostly affects premature infants with significant morbidity and mortality. Premature infants who require to be treated for conditions including respiratory distress syndrome have a higher risk of developing BPD. In spite of the improvement in clinical methods, the incidence of BPD has not reduced. In the present review, the pathogenesis of BPD is described along with the treatments available at present and the role of nursing in the management of BPD. Emerging preventive therapies for BPD are also discussed, including the use of recombinant human superoxide dismutase, which has been proven effective in reducing respiratory injury and its long-term effects.

Long-Term Neurodevelopment of Low-Birthweight, Preterm Infants with Patent Ductus Arteriosus

OBJECTIVE

To evaluate whether the presence of patent ductus arteriosus (PDA) in preterm infants worsens long-term neurodevelopmental outcomes.

STUDY DESIGN

This was a secondary observational analysis of data from 1090 preterm low-birthweight infants in the Infant Health and Development Program (IHDP), a multicenter longitudinal cohort study of outcomes assessed from 3 to 18 years of age. Multivariable analysis was adjusted for IHDP treatment group (intervention or follow-up), birth weight, maternal race, maternal education, infant sex, maternal preconception weight, Home Observation Measurement of the Environment (HOME) total score at 12 months, neonatal health index, and gestational age.

RESULTS

Of the 1090 patients (49% male) included in the analysis, 135 had a PDA. Mean birth weight (1322 g vs 1871 g; P < .0001) and gestational age (30.2 weeks vs 33.4 weeks, P < .0001) were lower and mean ventilator days (11.8 vs 1.3; P < .0001), vasopressor use (12.6% vs 1.2%; P < .0001), and congestive heart failure (8.9% vs 0.1%; P < .0001) were higher in the PDA group. There were no differences between the PDA and no-PDA groups in maternal education level and HOME total score at age 12 months. Multivariable analysis demonstrated no between-group differences in cognitive development or behavioral competence at age 3, 8, and 18 years.

CONCLUSIONS

The presence of a PDA in moderately preterm, low-birthweight infants does not impact long-term neurodevelopmental outcomes.

Early echocardiography does not predict subsequent treatment of symptomatic patent ductus arteriosus in extremely preterm infants

AIM

To determine whether early echocardiographic ductal parameters identified infants who subsequently received medical or surgical treatment of the patent ductus arteriosus (PDA).

METHODS

Infants <29 weeks had PDA size in 2D and colour, flow velocity and patterns obtained on days 1 and 3. Infants were followed up to identify those subsequently receiving treatment for symptomatic PDA by clinicians who were unaware of scan results. Receiver operator characteristics curves and logistic regression were performed.

RESULTS

Sixty infants were studied. Mean (SD) gestation and birthweight were 25.8 (1.5) weeks and 817 (190) grams, respectively. Twenty-four (40%) infants received medical treatment, and nine (15%) infants received surgical ligation of PDA at a median age of 12 and 37 days, respectively. PDA size on days 1 and 3, change in ductal size between days 1 and 3, flow pattern/velocity did not predict whether infants subsequently received medical or surgical management of PDA. Using logistic regression, gestation (p = 0.006) was the only factor that predicted whether infants would subsequently receive medical or surgical treatment for PDA in this cohort.

CONCLUSION

Echocardiographic ductal parameters on day 1 or 3 did not identify infants who received PDA treatment. Gestation was the most powerful predictor for receiving medical or surgical treatment of PDA.

Surgical management of a patent ductus arteriosus: Is this still an option?

The evolution of neonatal intensive care over the past decade has seen the role of surgical patent ductus arteriosus (PDA) ligation in preterm infants both decrease in scope and become laden with uncertainty. Associations of ligation with adverse neonatal and neurodevelopmental outcomes have rendered the ligation decision more challenging for clinicians and have been associated with a decline in surgical treatment, but these findings may be due to bias from confounding by indication in observational studies rather than a causal detrimental effect of ligation. Accordingly, ligation may still be indicated for infants with large ductal shunts and moderate-severe respiratory insufficiency in whom the prospect of timely spontaneous closure appears low. Ultimately a randomized trial of surgical ligation versus conservative management is necessary to assess the efficacy of this invasive intervention in a population of extremely preterm infants with large ductal shunts. Simultaneously, the transcatheter approach to ductal closure in the very immature infant represents an exciting therapeutic alternative but which is still in its infancy. Insights into the pathophysiology of postoperative cardiorespiratory deterioration, including the importance of left ventricular afterload, may help clinicians avoid instability and mitigate a potentially injurious aspect of surgical treatment. This review examines the evidence regarding the benefits and risks of PDA surgery in preterm neonates and provides a pathophysiology-based management paradigm to guide perioperative care in high-risk infants.

Patent ductus arteriosus, its treatments, and the risks of pulmonary morbidity

A persistent left-to-right shunt through a patent ductus arteriosus (PDA) increases the rate of hydrostatic fluid filtration into the lung's interstitium, impairs pulmonary mechanics, and prolongs the need for mechanical ventilation. In preclinical trials, pharmacologic PDA closure leads to improved alveolarization and minimizes the impaired postnatal alveolar development that is the pathologic hallmark of bronchopulmonary dysplasia (BPD). Although routine prophylactic treatment of a PDA on the day of birth does not appear to offer any more protection against BPD than delaying treatment for 2-3 days, recent evidence from quality improvement trials suggests that early pharmacologic treatment decreases the incidence of BPD compared with a treatment approach that exposes infants to a moderate-to-large PDA shunt for the first 7-10 days after birth. After the first week, routine pharmacologic treatment (compared with continued PDA exposure) no longer appears to alter the course of BPD development. Evidence from epidemiologic, preclinical, and randomized controlled trials demonstrate that early ductus ligation is an independent risk factor for the development of BPD.

Changing patterns of patent ductus arteriosus surgical ligation in the United States

Optimal management of patent ductus arteriosus (PDA) is unclear. One treatment, surgical ligation, is associated with adverse outcomes. We reviewed data from the Kids' Inpatient Database (2000-2012) to determine if PDA ligation rates: (1) changed over time, (2) varied geographically, or (3) influenced surgical complication rates. In 2012, 47,900 infants <1500g birth weight were born in the United States, including 2,800 undergoing PDA ligation (5.9%). Ligation was more likely in infants <1000g (85.9% vs. 46.2%), and associated with necrotizing enterocolitis (59.2% vs. 37.5%), BPD (54.6% vs. 15.2%), severe intraventricular hemorrhage (16.4% vs. 5.3%), and hospital transfer (37.6% vs. 16.4%). Ligation rates peaked in 2006 at 87.4 per 1000 hospital births, dropping to 58.8 in 2012, and were consistently higher in Western states. Infants undergoing ligation were more likely to experience comorbidities. Rates of ligation-associated vocal cord paralysis increased over time (1.2-3.9%); however, mortality decreased (12.4-6.5%). Thus, PDA ligation has become less frequent, although infants being ligated are smaller and more medically complex. Despite increase in some complications, mortality rates improved perhaps reflecting advances in care.

Left vocal cord paralysis after patent ductus arteriosus ligation: A systematic review

CONTEXT

Extremely premature (EP) infants are at increased risk of left vocal cord paralysis (LVCP) following surgery for patent ductus arteriosus (PDA).

OBJECTIVE

A Systematical Review was conducted to investigate the incidence and outcomes of LVCP after PDA ligation in EP born infants.

DATA SOURCES

Searches were performed in Cochrane, Medline, Embase, Cinahl and PsycInfo.

STUDY SELECTION

Studies describing EP infants undergoing PDA surgery and reporting incidence of LVCP were included.

DATA EXTRACTION AND SYNTHESIS

Study details, demographics, incidence of LVCP, diagnostic method and reported outcomes were extracted. DerSimonian and Laird random effect models with inverse variance weighting were used for all analyses.

STUDY APPRAISAL

The Newcastle-Ottawa scale for observational studies was used for quality assessment.

RESULTS

21 publications including 2067 infants were studied. The overall pooled summary estimate of LVCP incidence was 9.0% (95% CI 5.0, 15.0). However, the pooled incidence increased to 32% when only infants examined with laryngoscopy were included. The overall risk ratio for negative outcomes was higher in the LVCP group (2.20, 95% CI 1.69, 2.88, p = 0.01) compared to the non-LVCP-group.

CONCLUSIONS

Reported incidence of LVCP varies widely. This may be explained by differences in study designs and lack of routine vocal cords postoperative assessment. LVCP is associated with negative outcomes in EP infants. The understanding of long-term outcomes is scarce. Routine laryngoscopy may be necessary to identify all cases of LVCP, and to provide correct handling for infants with LVCP.

Post-ligation cardiac syndrome is associated with increased morbidity in preterm infants

OBJECTIVE

The influence of post-ligation cardiac syndrome (PLCS), a complication of patent ductus arteriosus (PDA) ligations, on neonatal outcomes is unknown. The purpose of this study was to determine the risks of PLCS on severe pulmonary morbidity and severe retinopathy of prematurity (ROP).

STUDY DESIGN

Retrospective cohort study of infants who underwent a PDA ligation between 2006 and 2015. Data were collected on patients with and without PLCS. The primary outcome was the difference in severe bronchopulmonary dysplasia (BPD) between groups. Secondary outcomes included discharge with home oxygen and severe ROP.

RESULT

A total of 100 infants that underwent PDA ligation during the study period were included in the study; 31 (31%) neonates developed PLCS. In adjusted analysis, PLCS was associated with increased risk for severe BPD (RR 1.67, 95% CI: 1.15-2.42) and home oxygen therapy (RR: 1.47, 95% CI: 1.09-1.99) only. No association with severe ROP was seen (RR: 1.48; 95% CI: 0.87-2.52).

CONCLUSION

PLCS is associated with severe neonatal pulmonary morbidity, but not with severe ROP. Further investigation is warranted to validate these results.

Retinopathy of prematurity: a review of risk factors and their clinical significance

Retinopathy of prematurity (ROP) is a retinal vasoproliferative disease that affects premature infants. Despite improvements in neonatal care and management guidelines, ROP remains a leading cause of childhood blindness worldwide. Current screening guidelines are primarily based on two risk factors: birth weight and gestational age; however, many investigators have suggested other risk factors, including maternal factors, prenatal and perinatal factors, demographics, medical interventions, comorbidities of prematurity, nutrition, and genetic factors. We review the existing literature addressing various possible ROP risk factors. Although there have been contradictory reports, and the risk may vary between different populations, understanding ROP risk factors is essential to develop predictive models, to gain insights into pathophysiology of retinal vascular diseases and diseases of prematurity, and to determine future directions in management of and research in ROP.

Neurodevelopmental outcomes of infants with very low birth weights are associated with the severity of their extra-uterine growth retardation

BACKGROUND

For infants with very low birth weights (VLBW), their neurodevelopmental outcomes are thought to be associated with extra-uterine growth retardation (EUGR). In this study, based on a single institute, we analyzed the association between different levels or severity of EUGR of VLBW infants and their neurodevelopmental outcomes later at a corrected age of 24 months.

METHODS

This is a hospital-based retrospective cohort study. The severity of EUGR was classified into three categories according to the z-score of discharge weight: z < -2.0, <-2.5, and <-3.0. The outcomes were assessed using the Bayley Scales of Infant Development-II (BSID-II) at a corrected age of 24 months. We then estimated the association of EUGR with low mental developmental index (MDI) or low psychomotor developmental index (PDI). Multiple logistic regression and stratified analyses were used to adjust for the possible confounding factors.

RESULTS

In total, 224 VLBW infants were enrolled in this study from 1997 to 2006. In the univariate analysis, EUGR for weight at discharge from hospital was associated with MDI <85 at the corrected age of 24 months, and this association was related to the severity of EUGR (z < -2.5, OR: 1.92 (1.04-3.53); z < -3.0, OR: 2.83 (1.26-6.36)). In addition, the relationship was not confounded by gender nor small for gestational age. The stratified analysis against hemodynamic significant patent ductus arteriosus also revealed that EUGR was an independent predictor for neurodevelopmental outcomes.

CONCLUSION

In VLBW preterm infants, EUGR was significantly associated with low MDI scores assessed at a corrected age of 24 months. Early evaluation and recognition of EUGR should be emphasized when caring for preterm infants.

Using benchmarking to identify inter-centre differences in persistent ductus arteriosus treatment: can we improve outcome?

OBJECTIVE

The aim of this study was to identify inter-centre differences in persistent ductus arteriosus treatment and their related outcomes. Materials and methods We carried out a retrospective, multicentre study including infants between 24+0 and 27+6 weeks of gestation in the period between 2010 and 2011. In all centres, echocardiography was used as the standard procedure to diagnose a patent ductus arteriosus and to document ductal closure.

RESULTS

In total, 367 preterm infants were included. All four participating neonatal ICU had a comparable number of preterm infants; however, differences were observed in the incidence of treatment (33-63%), choice and dosing of medication (ibuprofen or indomethacin), number of pharmacological courses (1-4), and the need for surgical ligation after failure of pharmacological treatment (8-52%). Despite the differences in treatment, we found no difference in short-term morbidity between the centres. Adjusted mortality showed independent risk contribution of gestational age, birth weight, ductal ligation, and perinatal centre.

CONCLUSIONS

Using benchmarking as a tool identified inter-centre differences. In these four perinatal centres, the factors that explained the differences in patent ductus arteriosus treatment are quite complex. Timing, choice of medication, and dosing are probably important determinants for successful patent ductus arteriosus closure.

Changes in the Diagnosis and Management of Patent Ductus Arteriosus from 2006 to 2015 in United States Neonatal Intensive Care Units

OBJECTIVE

To identify changes in the diagnosis, pharmacotherapy, and surgical ligation of patent ductus arteriosus (PDAs) in infants born premature and report on temporal changes in mortality and morbidity from a large volume of neonatal intensive care units (NICUs) in the US.

STUDY DESIGN

We queried the Pediatrix Clinical Data Warehouse for all inborn infants without major anomalies born between 23 and 30 weeks' gestation from 2006 to 2015 for a diagnosis of PDA, use of indomethacin or ibuprofen, history of ductal ligation, mortality, and major morbidities.

RESULTS

There were 829 091 infants entered in the Clinical Data Warehouse; 61 520 infants from 280 NICUs met our inclusion criteria. The diagnosis of PDA declined from 51% to 38% (P < .001), use of indomethacin or ibuprofen decreased from 32% to 18%, and PDA ligation decreased from 8.4% to 2.9% (both P < .001). During the study period, mortality decreased with no increase in any measured morbidity. Of the 163 sites with data for both periods, 128 (79%) showed a decrease in the diagnosis of PDA, and 132 (81%) showed a decrease in the use indomethacin and/or ibuprofen when 2011-2015 was compared with 2006-2010. Of 103 sites with at least 1 PDA ligation, 85 (83%) showed a decrease in PDA ligation in a similar comparison.

CONCLUSIONS

In this large population of infants <30 weeks' gestation from 280 NICUs across the US, there were significant decreases in the diagnosis and treatment of the PDA. Although there was no evidence of increased morbidities, it remains uncertain how these changes may directly affect infant outcomes.

Outcome after transcatheter occlusion of patent ductus arteriosus in infants less than 6 kg: A national study from United Kingdom and Ireland

OBJECTIVES

This study aimed to report our national experience with transcatheter patent ductus arteriosus (PDA) occlusion in infants weighing <6 kg.

BACKGROUND

The technique of transcatheter PDA closure has evolved in the past two decades and is increasingly used in smaller patients but data on safety and efficacy are limited.

METHODS

Patients weighing < 6 kg in whom transcatheter PDA occlusion was attempted in 13 tertiary paediatric cardiology units in the United Kingdom and Ireland were retrospectively analyzed to review the outcome and complications.

RESULTS

A total of 408 patients underwent attempted transcatheter PDA closure between January 2004 and December 2014. The mean weight at catheterization was 4.9 ± 1.0 kg and mean age was 5.7 ± 3.0 months. Successful device implantation was achieved in 374 (92%) patients without major complication and of these, complete occlusion was achieved in 356 (95%) patients at last available follow-up. Device embolization occurred in 20 cases (5%). The incidence of device related obstruction to the left pulmonary artery or aorta and access related peripheral vascular injury were low. There were no deaths related to the procedure.

CONCLUSIONS

Transcatheter closure of PDA can be accomplished in selected infants weighing <6 kg despite the manufacturer's recommended weight limit of 6 kg for most ductal occluders. The embolization rate is higher than previously reported in larger patients. Retrievability of the occluder and duct morphology needs careful consideration before deciding whether surgical ligation or transcatheter therapy is the better treatment option.

Patent ductus arteriosus in premature infants: to treat or not to treat?

OBJECTIVE

Closing patent ductus arteriosus (PDA) is a widely accepted approach in the management of very low birth weight (VLBW) infants. Our objective is to test the hypothesis that conservative management (no treatment) of PDA will not affect survival without chronic lung diseases (CLD).

STUDY DESIGN

This retrospective study utilizes a prospectively collected database to compare two cohorts of VLBW infants. Infants in the first group (2001 to 2009) had their PDA treated with pharmacological and if necessary with surgical ligation. PDA in the second group (2010 to 2014) was not treated with medical or surgical intervention. The primary outcome was survival without oxygen requirement at 36 weeks. Pulmonary and non-pulmonary morbidities were also compared. Logistic regression analyses were performed to control for confounders.

RESULTS

This study included 643 VLBW infants, of them 415 infants in the Treat group and 228 in the No-Treat group. The rate of survival without CLD did not differ between Treat and No-Treat groups (78.4% vs 83.9%, respectively; adjusted odds ratio (aOR)=1.72, confidence interval (CI): 0.92 to 3.23, P=0.09). Mortality declined in No-Treat group (15.2% vs 10.5%, aOR=0.51, CI: 0.25 to 0.99, P=0.049), but the two groups did not differ in the incidence of CLD among survivors (5.8% vs 5.0%,=P0.47). Pulmonary complications and non-pulmonary morbidities did not differ between groups.

CONCLUSIONS

Conservative management (no treatment) of PDA may not compromise survival without CLD and is not associated with increased morbidities in VLBW infants. Prospective physiological studies are needed to determine the sector of VLBW infants, if any, who could benefit from PDA treatment.

Association of Patent Ductus Arteriosus Ligation With Death or Neurodevelopmental Impairment Among Extremely Preterm Infants

IMPORTANCE

Observational studies have associated patent ductus arteriosus (PDA) ligation among preterm infants with adverse neonatal outcomes and neurodevelopmental impairment in early childhood, with a resultant secular trend away from surgical treatment. However, to our knowledge, studies have inadequately addressed sources of residual bias, including survival bias and major neonatal morbidities arising before exposure to ligation.

OBJECTIVE

Evaluate the association between PDA ligation vs medical management and neonatal and neurodevelopmental outcomes.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study of preterm infants younger than 28 weeks gestational age born between January 1, 2006, and December 31, 2012, with clinical and echocardiography diagnoses of hemodynamically significant PDA was conducted at 3 tertiary neonatal intensive care units and affiliated follow-up programs.

EXPOSURE

Surgical ligation vs medical management.

MAIN OUTCOMES AND MEASURES

The primary outcome was a composite of death or neurodevelopmental impairment (NDI) at 18 to 24 months corrected age. Secondary outcomes included death before discharge, NDI, moderate-severe chronic lung disease, and severe retinopathy of prematurity. Multivariable logistic regression analysis was used to adjust for perinatal and postnatal confounders.

RESULTS

Of 754 infants with hemodynamically significant PDA (mean [standard deviation] gestational age 25.7 [1.2] weeks and birth weight 813 [183] grams), 184 (24%) underwent ligation. Infants who underwent ligation had a higher frequency of morbidities before PDA closure, including sepsis, necrotizing enterocolitis, and a dependence on mechanical ventilation. After adjusting for perinatal characteristics and preligation morbidities, there was no difference in the odds of death or NDI (adjusted odds ratio (aOR), 0.83; 95% CI, 0.52-1.32), NDI (aOR, 1.27; 95% CI, 0.78-2.06), chronic lung disease (aOR, 1.36; 95% CI, 0.78-2.39) or severe retinopathy of prematurity (aOR, 1.61; 95% CI, 0.85-3.06). Ligation was associated with lower odds of mortality (aOR, 0.09; 95% CI, 0.04-0.21).

CONCLUSIONS AND RELEVANCE

Patent ductus arteriosus ligation among preterm neonates younger than 28 weeks gestational age was not associated with the composite outcome of death or NDI, and there were no differences in chronic lung disease, retinopathy of prematurity, or NDI among survivors. Mortality was lower among infants who underwent ligation, though residual survival bias could not be excluded. Previously reported associations of ligation with increased morbidity may be because of bias from confounding by indication.

General Anesthetics and Neurotoxicity: How Much Do We Know?

Over a decade ago, alarming findings were reported that exposure of the very young and very old animals to clinically used general anesthetics could be detrimental to their brains. The evidence presented suggested that the exposure to commonly used gaseous and intravenous general anesthetics induces the biochemical and morphologic changes in the immature and aging neurons ultimately resulting in their demise. More alarming was the demonstration of significant cognitive and behavioral impairments noted long after the initial anesthesia exposure. This article provides an overview of anesthesia-induced developmental neurotoxicity and commentary on the effects of general anesthesia on the aging brain.

Percutaneous Patent Ductus Arteriosus (PDA) Closure During Infancy: A Meta-analysis

CONTEXT

Patent ductus arteriosus (PDA) is a precursor to morbidity and mortality. Percutaneous (catheter-based) closure is the procedure of choice for adults and older children with a PDA, but use during infancy (<1 year) is not well characterized.

OBJECTIVE

Investigate the technical success and safety of percutaneous PDA closure during infancy.

DATA SOURCES

Scopus, Web of Science, Embase, PubMed, and Ovid (Medline) were searched through December 2015 with no language restrictions.

STUDY SELECTION

Publications needed to clearly define the intervention as percutaneous PDA closure during infancy (<1 year of age at intervention) and must have reported adverse events (AEs).

DATA EXTRACTION

The study was performed according to the Systematic Reviews and Meta-Analysis checklist and registered prospectively. The quality of the selected studies was critically examined. Data extraction and assignment of AE attributability and severity were independently performed by multiple observers. Outcomes were agreed on a priori. Data were pooled by using a random-effects model.

RESULTS

Thirty-eight studies were included; no randomized controlled trials were found. Technical success of percutaneous PDA closure was 92.2% (95% confidence interval [CI] 88.8-95.0). Overall AE and clinically significant AE incidence was 23.3% (95% CI 16.5-30.8) and 10.1% (95% CI 7.8-12.5), respectively. Significant heterogeneity and publication bias were observed.

LIMITATIONS

Limitations include lack of comparative studies, lack of standardized AE reporting strategy, and significant heterogeneity in reporting.

CONCLUSIONS

Percutaneous PDA closure during infancy is feasible and associated with few catastrophic AEs; however, the limitations constrain the interpretability and generalizability of the current findings.

Repeated Courses of Oral Ibuprofen in Premature Infants with Patent Ductus Arteriosus: Efficacy and Safety

BACKGROUND

There are limited data about the results of repeated oral ibuprofen (OIBU) treatment. This study aimed to describe patent ductus arteriosus (PDA) closure rates and adverse events after repeated courses of OIBU in premature infants with PDA.

METHODS

Preterm infants with hemodynamically significant (hs)PDA were enrolled in the study. If the first course of OIBU treatment failed, a second and, if required, third course was administered.

RESULTS

A total of 100 patients received OIBU. In six patients, treatment could not be completed due to death (n=3) and side effects (n=3). In three patients, adverse effects related to OIBU (thrombocytopenia and impairment of renal function) developed during the first course. During the second and third courses, no new adverse event occurred. After all courses, the PDA closure rate was determined as 88%. The rate was 71% after the first course, 40% after the second course, and 35% after the third course. Although the second course resulted in a significant increase in the closure rate (p<0.05), the rate did not increase significantly with the third course (p>0.05). The mean postnatal age at the start of the first dose of OIBU was not significantly different among the responders and non-responders to the first course (p>0.05). Clinical characteristics did not affect the closure rate significantly. The number of courses did not have a significant effect on death, when gestational age and birth weight were used as covariates [p=0.867, Exp(B)=0.901, 95% confidence interval=0.264-3.1].

CONCLUSION

A second course of OIBU seems effective and safe for use in preterm infants with hsPDA. Although a third course of OIBU results in PDA closure in some additional patients, the difference is not significant. Thus, surgical ligation should be considered after the second course, especially in patients with signs of severe heart failure.

A conservative treatment of patent ductus arteriosus in very low birth weight infants

BACKGROUND

Treatment of the patent ductus arteriosus (PDA) in the preterm infant remains contentious. There are numerous options of the PDA management from early targeted treatment, late (symptomatic) treatment to no treatment at all.

AIMS

To evaluate a three different PDA management approaches in very low birth weight (VLBW) infants.

STUDY DESIGN

A retrospective observational time series study of three cohorts of VLBW infants born between 2004 and 2011.

SUBJECTS

Infants in Symptomatic Treatment Group (STG) were echocardiographically evaluated when clinical signs suggestive of a PDA were present and treated if a haemodynamically significant PDA was confirmed. Early Targeted Group (ETG) underwent echocardiography within the first 48h and infants received ibuprofen if a large PDA was present. Conservative Treatment Group (CTG) was screened by echocardiography on day seven of life; patients with PDA were managed with increased positive end expiratory pressure and fluid restriction as a first line intervention.

OUTCOMES

The primary outcome was medical and surgical treatment in the three time periods. Secondary outcomes included mortality, severe periventricular and intraventricular haemorrhage, respiratory distress syndrome and chronic lung disease.

RESULTS

There were 138 infants diagnosed with PDA; 52 infants in STG, 52 infants in ETG and 34 infants in CTG. Ibuprofen therapy and ligation were less frequent in CTG. There was significantly decreased incidence of chronic lung disease in CTG compared to STG (18% vs. 51%; p=0.003) and to ETG (18% vs. 46%; p=0.02). There was no difference in the other short term outcomes.

CONCLUSION

Conservative treatment of persistent ductus arteriosus in VLBW infants is a feasible option and future randomized trials of conservative management are warranted.