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

Transcatheter and Surgical Ductus Arteriosus Closure in Very Low Birth Weight Infants: 2018-2022

BACKGROUND AND OBJECTIVE

The optimal patent ductus arteriosus (PDA) closure method in very low birth weight (VLBW) infants is uncertain. In 2019, the first transcatheter occlusion device was approved in the United States for infants ≥700 g. We described survival and short-term outcomes among VLBW infants who underwent transcatheter or surgical PDA closure (2018-2022).

METHODS

Vermont Oxford Network members submitted data on infants born from 401 to 1500 g or 22 to 29 weeks' gestational age. Adjusted risk ratios (aRR) for survival, length of stay (LOS), prematurity complications, and discharge support were used to compare transcatheter versus surgical closure. Subgroup analyses were conducted for infants with birth weight ≥700 g and born in 2020-2022.

RESULTS

Overall, 6410 of 216 267 infants at 726 hospitals received invasive PDA treatment. Transcatheter closure increased from 29.8% in 2018 to 71.7% in 2022. VLBW infants undergoing transcatheter closure had higher survival (adjusted rate ratio [aRR] 1.03; 1.02-1.04) with similar LOS (aRR 1.00; 0.97-1.03), neonatal complications (aRR 1.00; 0.98-1.01), and receipt of discharge support (aRR 0.94; 0.89-1.01). In subgroup analyses, survival (aRR 1.02; 1.00-1.04) and discharge support (aRR 0.90; 0.81-1.01) were similar between groups, whereas selected neonatal complications (aRR 0.95; 0.93-0.98) and LOS (aRR 0.95; 0.90-0.99) were lower after transcatheter closure.

CONCLUSIONS

Transcatheter PDA closure in VLBW infants was increasingly used after 2018. Selected short-term outcomes for infants receiving transcatheter closure may be more favorable, compared with surgical, and warrants further clinical investigation.

Lung ultrasound score in the decision of patent ductus arteriosus closure in neonates

PURPOSE

We aimed to investigate the role of lung ultrasound (LUS) score in the closure of hemodynamically insignificant patent ductus arteriosus (PDA) and the clinical findings of the patients before and after closure.

METHODS

The study groups (107 preterm neonates under 34 gestational weeks) were classified as hemodynamically significant PDA (group 1), hemodynamically insignificant PDA with closure therapy (group 2), hemodynamically insignificant PDA without closure therapy (group 3), and no PDA group (group 4) based on the echocardiography. 6- and 10-region LUS scores were compared for each group.

RESULTS

There was a significant difference between groups 1 and 3 on first, third, and seventh days. In contrast, groups 1 and 2 had similar LUS scores on the first, third, and seventh days. There was a negative correlation between LUS scores on the first and third days and gestational age, birth weight, the first- and fifth-minute APGAR scores, and there was a positive correlation between aortic root to left atrium ratio, and PDA diameter/weight ratio.

CONCLUSION

We observed that LUS scores in patients with hemodynamically insignificant PDA treated with closure therapy were similar to in patients with hemodynamically significant PDA. Thus, LUS score can have role in PDA closure in preterm neonates. However, more comprehensive studies are needed.

Role of patent ductus arteriosus in preterms in long-term outcome

OBJECTIVE

This study aimed to determine long-term neurodevelopmental outcome and cerebral oxygenation in extremely preterm infants, comparing those with a hemodynamic significant patent ductus arteriosus (hsPDA) to those without.

STUDY DESIGN

We included infants born before 28 weeks of gestation from 2008 to 2010 with routine echocardiography. Prior to echocardiography, regional cerebral oxygen saturation was measured. At 5 years of age, we evaluated neurodevelopmental outcomes using the Movement Assessment Battery for Children 2nd Dutch edition for motor skills and the Wechsler Preschool and Primary Scale of Intelligence 3rd Dutch edition for cognition.

RESULTS

A total of 66 infants (gestational age 26.6 ± 0.9 weeks, birth weight 912 ± 176 g) were included, 34 infants with a hsPDA (including treatment). The group infants with hsPDA showed lower pre-closure cerebral saturation levels (58.2 % ±7.8 % versus 62.8 % ±7.0 %; p = 0.01). At 5 years, impaired motor outcome occurred more often in infants with hsPDA (17 (53 %) vs. 7 (23 %); p = 0.01). In multivariate analysis existence of hsPDA remained unfavourably related to the motor subdomain "aiming and catching". There were no potential effects of hsPDA on cognitive performance at 5 years of age.

CONCLUSION

Treatment-receiving infants with hsPDA appear to exhibit motor deficits, specifically in "aiming and catching", by the age 5. Persistent ductal patency could be a contributing factor.

Transcatheter closure in preterm infants with patent ductus arteriosus: feasibility, results, hemodynamic monitoring and future prospectives

Ductal patency of preterm infants is potentially associated with long term morbidities related to either pulmonary overflow or systemic steal. When an interventional closure is needed, it can be achieved with either surgical ligation or a catheter-based approach.Transcatheter PDA closure is among the safest of interventional cardiac procedures and it is the first choice for ductal closure in adults, children, and infants weighing more than 6 kg. In preterm and very low birth weight infants, it is increasingly becoming a valid and safe alternative to ligation, especially for the high success rate and the minor invasiveness and side effects. Nevertheless, being it performed at increasingly lower weights and gestational ages, hemodynamic complications are possible events to be foreseen.Procedural steps, timing, results, possible complications and available monitoring systems, as well as future outlooks are here discussed.

Fluid Intake in the First Week of Life and the Duration of Hemodynamically Significant Patent Ductus Arteriosus in Extremely Preterm Infants

OBJECTIVE

This study aimed to determine the association between daily fluid intake and the duration of hemodynamically significant patent ductus arteriosus (hsPDA).

STUDY DESIGN

This is a retrospective cohort study of extremely preterm infants (<29 weeks) admitted in the Neonatal Intensive Care Unit of the Advent Health for Children from January 2013 to March 2016, if hsPDA was diagnosed in first week of life and serial echocardiograms were available. Diagnosis of hsPDA was based on a scoring system and its duration was estimated from serial echocardiograms. Cohort was divided into two groups based on duration of hsPDA (<1week, group A and ≥1 week, group B). Daily fluid intake was categorized as prescribed and actual. Prescribed volume was ordered by clinicians based on birth weight, not including trophic feeds, intravenous (IV) boluses or transfusions, etc. Actual intake was calculated by the electronic medical records based on daily weights and included all enteral or parenteral fluids. Multivariate analysis was performed to determine an association between total daily fluid intake over the first week of life and the duration of hsPDA. Two groups were compared to observe the difference between prescribed and actual daily fluid intakes.

RESULTS

We enrolled 50 infants in group A and 76 in group B. Infants in group B were of significantly lower gestation and required prolonged ventilation and hospitalization. An association between higher fluid intake in the first 2 days of life and prolonged duration of hsPDA was confirmed by multivariate analysis. Actual fluid intake was significantly higher than prescribed total fluid intake in first 4 days of life for infants in both groups.

CONCLUSION

In extremely preterm infants, higher fluid intake in first 2 days of life is associated with prolonged duration of hsPDA. Actual daily fluid intake can be significantly higher than prescribed daily fluids due to daily weight changes and additional fluid administration.

KEY POINTS

· In preterm infants, actual daily fluid intake may be higher than prescribed volume.. · Higher daily fluid intake in first week of life is associated with prolonged duration of PDA.. · PDA scoring system can be helpful for objective assessment of PDA in preterm infants..

Delayed Surgical Closure of the Patent Ductus Arteriosus: Does the Brain Pay the Price?

OBJECTIVE

To investigate the relation between duration of hemodynamically significant patent ductus arteriosus (PDA), cerebral oxygenation, magnetic resonance imaging-determined brain growth, and 2-year neurodevelopmental outcome in a cohort of infants born preterm whose duct was closed surgically.

STUDY DESIGN

Infants born preterm at <30 weeks of gestational age who underwent surgical ductal closure between 2008 and 2018 (n = 106) were included in this observational study. Near infrared spectroscopy-monitored cerebral oxygen saturation during and up to 24 hours after ductal closure and a Bayley III developmental test at the corrected age of 2 years is the institutional standard of care for this patient group. Infants also had magnetic resonance imaging at term-equivalent age.

RESULTS

In total, 90 infants fulfilled the inclusion criteria (median [range]: 25.9 weeks [24.0-28.9]; 856 g [540-1350]. Days of a PDA ranged from 1 to 41. Multivariable linear regression analysis showed that duration of a PDA negatively influenced cerebellar growth and motor and cognitive outcome at 2 years of corrected age.

CONCLUSIONS

Prolonged duration of a PDA in this surgical cohort is associated with reduced cerebellar growth and suboptimal neurodevelopmental outcome.

Fresh Frozen Plasma Transfusion: An Independent Risk Factor for Hemodynamically Significant Patent Ductus Arteriosus in Premature Infants

OBJECTIVE

The incidence of patent ductus arteriosus (PDA), a major complication of prematurity, may be reduced by restricting fluid administration. Prophylactic fresh frozen plasma (FFP) transfusion may reduce the incidence of intraventricular hemorrhage in these infants, but risks transfusion-related volume overload. We conducted a retrospective study to investigate whether FFP transfusion is a risk factor for hemodynamically significant PDA (hsPDA) in very low birth weight (BW) premature infants.

STUDY DESIGN

From January 2009 to December 2014, 102 premature infants with gestational age (GA) less than or equal to 30 weeks were admitted to a level III neonatal intensive care unit, and 88 patients were enrolled. Patients were further divided into non-hsPDA (n = 29) and hsPDA groups (n = 59). We retrospectively reviewed demographic characteristics and various perinatal and postnatal variables. Univariate and multivariable analyses were performed to identify risk factors for hsPDA.

RESULTS

Compared with non-hsPDA patients, hsPDA patients had lower mean BW and GA, a higher incidence of severe respiratory distress symptoms, perinatal infection, use of surfactant, and need for FFP transfusion. However, multivariable logistic regression analysis showed that only FFP transfusion remained an independent risk factor for hsPDA (adjusted odds ratio = 3.880, 95% confidence interval: 1.214-12.402, p = 0.022) after adjusting for confounding factors.

CONCLUSION

FFP transfusion is a significant risk factor for the subsequent development of hsPDA in our study population. FFP transfusion may complicate the fluid management of premature infants and increase the risk of hsPDA.

KEY POINTS

· Hemodynamic significant PDA is an important complication of preterm infant.. · FFP transfusion may complicate the fluid management of premature infants.. · FFP transfusion is an independent risk factor for hsPDA in very low birth weight premature infants..

International Variation in the Management of Patent Ductus Arteriosus and Its Association with Infant Outcomes: A Survey and Linked Cohort Study

OBJECTIVE

To assess whether treating patients with a presymptomatic patent ductus arteriosus (PDA), based on early routine echocardiography, performed regardless of clinical signs, improved outcomes.

STUDY DESIGN

This multicenter, survey-linked retrospective cohort study used an institutional-level questionnaire and individual patient-level data and included infants of <29 weeks of gestation born in 2014-2016 and admitted to tertiary neonatal intensive care units (NICUs) of 9 population-based national or regional neonatal networks. Infants in NICUs receiving treatment of presymptomatic PDA identified by routine echocardiography and those not were compared for the primary composite outcome (early death [≤7 days after birth] or severe intraventricular hemorrhage) and secondary outcomes (any in-hospital mortality and major morbidities).

RESULTS

The unit survey (response rates of 86%) revealed a wide variation among networks in the treatment of presymptomatic PDA (7%-86%). Among 246 NICUs with 17 936 infants (mean gestational age of 26 weeks), 126 NICUs (51%) with 7785 infants treated presymptomatic PDA. The primary outcome of early death or severe intraventricular hemorrhage was not significantly different between the NICUs treating presymptomatic PDA and those who did not (17% vs 21%; aOR 1.00, 95% CI 0.85-1.18). The NICUs treating presymptomatic PDA had greater odds of retinopathy of prematurity treatment (13% vs 7%; aOR 1.47, 95% CI 1.01-2.12); however, it was not significant in a sensitivity analysis excluding Japanese data.

CONCLUSIONS

Treating presymptomatic PDA detected by routine echocardiography was commonplace but associated with no significant benefits. Well-designed trials are needed to assess the efficacy and safety of early targeted PDA treatment.

Comparative safety and efficacy of paracetamol versus non-steroidal anti-inflammatory agents in neonates with patent ductus arteriosus: a systematic review and meta-analysis of randomized controlled trials

AIM

Ibuprofen and indomethacin are the preferred drug treatment for patent ductus arteriosus (PDA) in preterm neonates. The comparative safety and efficacy of paracetamol as an alternative has not yet been well-established. The aim of our study was to define the comparative efficacy and safety of paracetamol versus ibuprofen and indomethacin for PDA METHODS: We performed a systematic literature search in Pubmed, Scopus and Cochrane databases on randomized controlled trials comparing the efficacy and/or the safety of paracetamol versus ibuprofen and/or indomethacin and meta-analyzed the available data.

RESULTS

There were 1718 neonates from 20 eligible studies. Paracetamol did not differ from ibuprofen or indomethacin regarding the primary [OR: 0.93 (95% CI: 0.69-1.26), p-value: 0.650, when compared to ibuprofen, and OR: 0.78 (95% CI: 0.20-3.02), p-value: 0.716, when compared to indomethacin] and overall [OR: 1.17 (95% CI: 0.82-1.66), p-value: 0.394, when compared to ibuprofen, and OR: 1.12 (95% CI: 0.58-2.15), p-value: 0.733, when compared to indomethacin] PDA closure rates. Paracetamol resulted in significantly reduced risk of oliguria and a tendency towards less gastrointestinal bleeding.

CONCLUSION

There was no significant difference between paracetamol and ibuprofen or indomethacin in the PDA closure rates. However, paracetamol caused less adverse effects.

Impact of patent ductus arteriosus shunt size and duration on risk of death or severe respiratory morbidity in preterm infants born in China

The purpose of this study is to assess whether duration and size of the arterial duct were associated with severe respiratory morbidity and mortality in preterm infants. All echocardiography evaluations for patent ductus arteriosus (PDA) in a cohort of preterm infants, born at a gestational age less than 28 weeks, from birth up to 36 weeks of postconceptional age or final ductal closure were reviewed. Ductal size was measured at the pulmonary end. PDA was classified as small (E1: ductal diameter (DD) ≤ 1.5 mm), moderate (E2: 1.5 mm < DD ≤ 2.5 mm), or large (E3) (DD > 2.5 mm). The primary outcome was adverse outcome defined by the composite outcome of bronchopulmonary dysplasia (BPD) or death. Infants in whom the primary outcome occurred were classified as "high-risk" whereas patients who did not satisfy this outcome were classified as "low-risk". Intergroup comparison (high vs. low risk) was performed using univariate and multivariate analyses. A total of 135 infants, born between 2010 and 2020, were evaluated. The primary outcome was satisfied in 46 (34.1%) patients. The high-risk group was characterized by increased duration of exposure to PDA of any (E1/E2/E3) grade (44 vs. 25.5 days, p = .0004), moderate or large (E2/E3) PDA (30.5 vs. 11.5 days, p < .0001), moderate (E2) PDA (10.8 vs.6 days, p = 0.05), and large (E3) PDA (11.5 vs.0 days, p < .0001) compared with low-risk group. Lower gestational age, prolonged duration of mechanical ventilation, higher rate of inotrope use, pharmacological therapy, and PDA ligation were also associated with development of BPD or death (high-risk group). After adjusting for confounders, the rate of inotrope use [OR 2.688, 95% CI (1.011-7.142), p = 0.047], duration of large (E3) PDA [OR 1.060, 95% CI (1.005-1.118), p = 0.03], and mechanical ventilation [OR 1.130, 95% CI (1.064-1.200), p = 0.0001] were independently associated with the composite of BPD or death. Among infants who developed BPD, 27 were classified as grade I and 18 as grade II BPD, respectively. Infants with grade II BPD had prolonged MV (20.0 vs. 9.0 days, p = 0.024), prolonged exposure to PDA of any grade (55.8 vs. 36.0 days, p = 0.03), and prolonged exposure to large (E3) PDA compared with infants with grade I BPD.   Conclusion: Prolonged exposure to a large PDA was associated with severe respiratory morbidity and mortality in preterm infants. The modulator role of early intervention, in the most pathologic shunts, on severe respiratory morbidity in preterm infants should be tested in well-designed clinical trials. What is Known: • Current guidelines recommended against accelerating PDA closure of preterm infants within 2 weeks of life, with low certainty evidence indicating improved long-term outcomes. • Recent studies suggest that conservative approach regarding PDA management has detrimental effects on the respiratory outcomes in a subgroup population. What is New: • Persistent patency of significant PDA is associated with increased risk of BPD/death in extremely preterm infants. • Targeted intervention of PDA is beneficial for the at-risk preterm infants with increased PDA hemodynamic significance.

Differential effects of ibuprofen and indomethacin on cerebral oxygen kinetics in the very preterm baby

BACKGROUND

Ibuprofen is preferred to indomethacin for treatment of a significant patent ductus arteriosus (PDA) in preterm babies despite indomethacin being associated with a lower risk of intraventricular haemorrhage. This difference is thought to relate to the discrepant effects of each medication on cerebral oxygen kinetics yet the effect of ibuprofen on cerebral perfusion is uncertain.

METHODS

Forty-eight babies < 30 weeks with a significant PDA, defined by echocardiography, were randomly assigned to either indomethacin or ibuprofen (n = 24 per group) and stratified by gestation and chronologic age. Cerebral blood flow [total internal carotid blood flow (TICF)] and oxygen physiology [oxygen delivery (modCerbDO₂) and consumption (modCerbVO₂)] were measured using cranial Doppler ultrasound and near-infrared spectroscopy, and cerebral oxygen extraction (cFTOE) calculated, immediately before and following administration. Temporal and treatment related changes were analysed.

RESULTS

A fixed effect of time was seen for TICF (p = 0.03) and therefore modCerbDO₂ (p = 0.046) and cFTOE (p = 0.04) for indomethacin alone. In the indomethacin group, TICF and modCerbDO₂ fell from baseline to 5 and 30 min respectively (TICF p < 0.01, cDO₂ p = 0.01) before increasing from 5 min to 24 h (p < 0.01) and 30 min and 24 h (p < 0.01) timepoints. cFTOE peaked at 30 min (p = 0.02) returning to baseline at 24 h. There was a parallel increase in arterial lactate.

CONCLUSION

Indomethacin significantly reduces cerebral blood flow soon after administration, resulting in a parallel increase in oxygen extraction and arterial lactate. This implies that the balance of oxygen kinetics at the time of treatment may be critical in very preterm babies with significant PDA.

Fluid Intake in the First Week of Life and the Duration of Hemodynamically Significant Patent Ductus Arteriosus in Extremely Preterm Infants

OBJECTIVE

 This study aimed to determine the association between daily fluid intake and the duration of hemodynamically significant patent ductus arteriosus (hsPDA).

METHODS

 This is a retrospective cohort study of extremely preterm infants (<29 weeks) admitted in the Neonatal Intensive Care Unit of the Advent Health for Children from January 2013 to March 2016, if hsPDA was diagnosed in first week of life and serial echocardiograms were available. Diagnosis of hsPDA was based on a scoring system and its duration was estimated from serial echocardiograms. Cohort was divided into two groups based on duration of hsPDA (<1week, group A and ≥1 week, group B). Daily fluid intake was categorized as prescribed and actual. Prescribed volume was ordered by clinicians based on birth weight, not including trophic feeds, intravenous (IV) boluses or transfusions, etc. Actual intake was calculated by the electronic medical records based on daily weights and included all enteral or parenteral fluids. Multivariate analysis was performed to determine an association between total daily fluid intake over the first week of life and the duration of hsPDA. Two groups were compared to observe the difference between prescribed and actual daily fluid intakes.

RESULTS

 We enrolled 50 infants in group A and 76 in group B. Infants in group B were of significantly lower gestation and required prolonged ventilation and hospitalization. An association between higher fluid intake in the first 2 days of life and prolonged duration of hsPDA was confirmed by multivariate analysis. Actual fluid intake was significantly higher than prescribed total fluid intake in first 4 days of life for infants in both groups.

CONCLUSION

 In extremely preterm infants, higher fluid intake in first 2 days of life is associated with prolonged duration of hsPDA. Actual daily fluid intake can be significantly higher than prescribed daily fluids due to daily weight changes and additional fluid administration.

KEY POINTS

· In preterm infants, actual daily fluid intake may be higher than prescribed volume.. · Higher daily fluid intake in first week of life is associated with prolonged duration of PDA.. · PDA scoring system can be helpful for objective assessment of PDA in preterm infants..

Percutaneous Closure of the Patent Ductus Arteriosus in Very-Low-Weight Infants

In view of the known complications of drug therapy and open surgical ligation, and the potential for prolonged patent ductus arteriosus (PDA) exposure to be harmful, health care practitioners have sought new approaches to achieve definitive ductal closure. Interest in percutaneous (catheter-based) PDA closure has emerged within the neonatal community as a viable treatment option, because it has been fueled by recent procedural and device modifications, as well as mounting feasibility and safety data. Herein, we provide a contemporary review of percutaneous PDA closure among infants at the crux of the medical debate-very-low-weight infants (≤1,500 g), including: 1) characterization of traditional PDA treatments (drug therapy, open surgical ligation) and conservative (nonintervention) management options; 2) a general overview of the major procedural steps of percutaneous ductal closure, including efforts to reduce thrombotic complications and the emergence of a novel US Food and Drug Administration-approved device; 3) a systematic review and meta-analysis to better understand risk profiles of percutaneous PDA closure in this population; and 4) discussion of current gaps in our understanding of optimal PDA care, including the critical need for well-designed, randomized, controlled clinical trials.

Outcomes of Extremely Premature Infants Comparing Patent Ductus Arteriosus Management Approaches

OBJECTIVE

To evaluate the change in the proportion of deaths/bronchopulmonary dysplasia (BPD) among premature infants (born <26 and 26-29 weeks of gestational age) following a policy change to a strict nonintervention approach, compared with standard treatment.

STUDY DESIGN

We examined 1249 infants (341 born <26 weeks of gestational age) at 2 comparable sites. Site 1 (control) continued medical treatment/ligation, and site 2 (exposed) changed to a nonintervention policy in late 2013. Using the difference-in-differences approach, which accounts for time-invariant differences between sites and secular trends, we assessed changes in death or BPD separately among infants born 26-29 weeks and <26 weeks of gestational age in 2 epochs (epoch 1: 2011-2013; epoch 2: 2014-2017).

RESULTS

Baseline characteristics were similar across sites and epochs. Medical treatment/ligation use remained stable at site 1 but declined progressively to 0% at site 2, indicating adherence to policy. We saw no difference in death/BPD among infants born at 26-29 weeks of gestational age (12%, 95% CI -1% to 24%). However, incidence of death/BPD increased by 31% among infants born <26 weeks of gestational age (95% CI 10%-51%) in site 2, whereas there was no change in outcomes in site 1. The Score for Neonatal Acute Physiology-Version II, used as a control outcome, did not change in either site, suggesting that our findings were not due to changes in patients' severity.

CONCLUSIONS

Adherence to a strict conservative policy did not impact death or BPD among 26 weeks but was associated with a significant rise in infants born <26 weeks.

Comparison of standard versus high-dose ibuprofen for the treatment of hemodynamically significant patent ductus arteriosus in preterm infants

OBJECTIVE

To evaluate the effectiveness and safety of standard vs. high-dose ibuprofen for the treatment of hemodynamically significant patent ductus arteriosus(hs-PDA).

STUDY DESIGN

A retrospective study of preterm infants who received either standard (10-5-5 mg/kg/day) or high (postnatal age 1-3 days: 10-5-5 mg/kg/day; 3-5 days: 15-7.5-7.5 mg/kg/day; >5 days: 20-10-10 mg/kg/day) dose ibuprofen for hs-PDA was conducted.

RESULT

Sixty preterm infants with a mean birthweight of 898.2 (±262.6) g and mean gestational age of 26.3 (±0.6) weeks were included. High-dose ibuprofen was associated with a 21%(95% CI, -1.87 to 39.06%; p = 0.07) absolute reduction in PDA ligation compared to standard-dose ibuprofen. On adjusted analysis, receipt of standard-dose ibuprofen (OR 7.37, 95% CI, 1.2-45.27; p = 0.03) independently predicted increased PDA ligation risk. There were no differences in oliguria, NEC, or BPD between groups.

CONCLUSION

High-dose ibuprofen may significantly reduce PDA ligations. No difference in the safety profile with high-dose ibuprofen as compared to the standard-dose regimen was demonstrated.

Evidence for the Management of Bronchopulmonary Dysplasia in Very Preterm Infants

Background: Very preterm birth often results in the development of bronchopulmonary dysplasia (BPD) with an inverse correlation of gestational age and birthweight. This very preterm population is especially exposed to interventions, which affect the development of BPD. Objective: The goal of our review is to summarize the evidence on these daily procedures and provide evidence-based recommendations for the management of BPD. Methods: We conducted a systematic literature research using MEDLINE/PubMed on antenatal corticosteroids, surfactant-replacement therapy, caffeine, ventilation strategies, postnatal corticosteroids, inhaled nitric oxide, inhaled bronchodilators, macrolides, patent ductus arteriosus, fluid management, vitamin A, treatment of pulmonary hypertension and stem cell therapy. Results: Evidence provided by meta-analyses, systematic reviews, randomized controlled trials (RCTs) and large observational studies are summarized as a narrative review. Discussion: There is strong evidence for the use of antenatal corticosteroids, surfactant-replacement therapy, especially in combination with noninvasive ventilation strategies, caffeine and lung-protective ventilation strategies. A more differentiated approach has to be applied to corticosteroid treatment, the management of patent ductus arteriosus (PDA), fluid-intake and vitamin A supplementation, as well as the treatment of BPD-associated pulmonary hypertension. There is no evidence for the routine use of inhaled bronchodilators and prophylactic inhaled nitric oxide. Stem cell therapy is promising, but should be used in RCTs only.

Patent ductus arteriosus management and the drift towards therapeutic nihilism - What is the evidence?

The published literature on patent ductus arteriosus (PDA) management is challenging to interpret due to poorly designed trials with high rates of open label treatments, homogenisation of patients with varying physiological subtypes, poor treatment efficacy, and spontaneous closure in more mature infants. The perceived lack of clinical benefit has led to a drift away from medical and surgical treatment of all infants with a PDA. This therapeutic nihilism as a default response to PDA management fails to recognise the physiological relevance of a left-to-right shunt with early haemodynamic instability after birth and subsequent pulmonary volume overload with prolonged exposure. Clinicians need to know if therapeutic nihilism is safe. This review will provide an overview of the available data on the efficacy of known PDA treatments, conservative management and supportive care measures that are currently applied.

Bedside cardiopulmonary ultrasonography evaluates lung water content in very low-weight preterm neonates with patent ductus arteriosus

BACKGROUND

Patent ductus arteriosus (PDA) is a common congenital heart abnormality in preterm neonates with a high incidence in neonates with very low birth weights. When PDA persists, interstitial lung water content increases, which could lead to abnormal circulation hemodynamics and pulmonary edema. It is important to perform early and reliable assessment of lung water content in very low-weight preterm neonates with persistent PDA.

AIM

To evaluate the role of bedside cardiopulmonary ultrasonography in the lung water content assessment in very low-weight preterm neonates with persistent PDA.

METHODS

From January 2018 to March 2020, 69 very low-weight preterm neonates with echocardiography-confirmed PDA were selected as the PDA group. At the same time, 89 very low-weight preterm neonates without PDA were randomly selected as the control group. All neonates underwent echocardiography and 6-segment lung ultrasonography on the fourth day after birth. The clinical characteristics and main ultrasonography results were compared between the two groups. Pearson’s analysis was used to analyze the correlation between lung ultrasonography score (LUS) and other related clinical and ultrasonography results in all neonates. In the PDA group, PDA diameters were recorded, and the correlation with LUS and left atrium to aortic (LA/AO) dimension ratio were also analyzed. LA/AO ratio is one of the ultrasonic diagnostic criteria for hemodynamically significant PDA. When the ratio is ≥ 1.5, it suggests the possibility of hemodynamic changes in persistent PDA. A receiver operating characteristic curve was established using the sensitivity of LUS to predict the hemodynamic changes in neonates with PDA as the ordinate and 1-specificity as the abscissa.

RESULTS

A total of 158 neonates were enrolled in this study, including 69 in the PDA group and 89 in the control group. There were no statistical differences in sex, gestational age, birth weight, ventilator dependence, hospitalization length and left ventricular ejection fraction between the two groups (P > 0.05). The LUS and LA/AO ratio in the PDA group were higher than those in the control group (P < 0.05), but there was no difference of LUS in neonates with or without use of the ventilator (t = 0.58, P = 0.16). In all cases, LUS was negatively correlated with gestational age (r = -0.28, P < 0.01) and birth weight (r = -0.36, P < 0.01), while positively correlated with the LA/AO ratio (r = 0.27, P < 0.01). In the PDA group, PDA diameter was positively correlated with the LA/AO ratio (r = 0.39, P < 0.01) and LUS (r = 0.31, P < 0.01). Receiver operating characteristic results showed that LUS had the moderate accuracy for predicting hemodynamic changes in PDA (area under the curve = 0.741; sensitivity = 93.75%; specificity = 50.94%).

CONCLUSION

Bedside cardiopulmonary ultrasonography can evaluate lung content in neonates with PDA and predict the possibility of hemodynamic changes in persistent PDA.

Conservative Management of Patent Ductus Arteriosus in Preterm Infants-A Systematic Review and Meta-Analyses Assessing Differences in Outcome Measures Between Randomized Controlled Trials and Cohort Studies

Objective: This study aims to evaluate outcome after conservative management (no pharmacological/surgical intervention other than fluid restriction, diuretics, or ventilator adjustments) compared with active (pharmacological and/or surgical) treatment for patent ductus arteriosus (PDA) in preterm infants and analyze differences in outcome between randomized controlled trials (RCTs) and cohort studies. Study Design: This is a systematic literature review using PubMed, EMBASE, and Cochrane library. RCTs and cohort studies comparing conservative management with active treatment were included. Meta-analysis was used to compare conservative management with any active (pharmacological and/or surgical), any pharmacological (non-prophylactic and prophylactic), and/or surgical treatment for mortality as primary and major neonatal morbidity as secondary outcome measure. Fixed-effect analysis was used, unless heterogeneity (I ²) was >50%. Outcome is presented as relative risk (RR) with 95% confidence interval. Results: Twelve cohort studies and four RCTs were included, encompassing 41,804 and 720 patients, respectively. In cohort studies, conservative management for PDA was associated with a significantly higher risk for mortality (RR, 1.34 [1.12-1.62]) but a significantly lower risk for bronchopulmonary dysplasia (RR, 0.55 [0.46-0.65]), necrotizing enterocolitis (RR, 0.85 [0.77-0.93]), intraventricular hemorrhage (RR, 0.88 [0.83-0.95]), and retinopathy of prematurity (RR, 0.47 [0.28-0.79]) compared with any active PDA treatment. Meta-analysis of the RCTs revealed no significant differences in outcome between conservative management and active treatment. Conclusion: No differences in mortality or morbidity for conservative management compared with active treatment regimens were observed in RCTs. Findings from cohort studies mainly highlight the lack of high-quality evidence for conservative management for PDA in preterm infants.

Conservative Treatment Without Any Intervention Compared With Other Therapeutic Strategies for Symptomatic Patent Ductus Arteriosus in Extremely Preterm Infants: A Nationwide Cohort Study in Korea

Objective: Although symptomatic treatment is the most preferred treatment strategy for proven symptomatic patent ductus arteriosus (PDA), a considerable number of infants only received conservative treatment without any pharmacological or surgical interventions in the lower gestational age and lower birth weight group in Korea. We compared in-hospital outcomes of infants treated conservatively without any intervention and those of infants managed by other therapeutic strategies in extremely preterm infants with symptomatic PDA. Methods: A prospectively collected cohort study for 2,303 infants with gestational ages <28 weeks from the Korean Neonatal Network database. These infants were classified into four groups according to the presence of PDA-related symptoms and therapeutic treatment strategy: prophylactic treatment group, pre-symptomatic treatment (PST) group, symptomatic treatment (ST) group, and conservative treatment (CT) without any intervention group. Results: In multivariable logistic regression analysis, the risk of death was significantly decreased in the PST group (adjusted odds ratio [aOR] = 0.507; 95% confidence interval [CI] 0.311-0.826) and ST group (aOR = 0.349; 95% CI: 0.230-0.529) compared with the CT group. However, the risk of composite outcome of severe bronchopulmonary dysplasia or death had not increased in the PST group and ST group. Neonatal death due to pulmonary hemorrhage or neurological disease was significantly higher in the CT group than in the PST group or ST group. Conclusion: In extremely preterm infants, who are at highest risk of PDA-related morbidities and mortality, even less interventional approach for PDA can be allowed; the rescued pharmacological or surgical interventions are necessary if they met the criteria for hemodynamically significant PDA.

Effect of Nonintervention vs Oral Ibuprofen in Patent Ductus Arteriosus in Preterm Infants: A Randomized Clinical Trial

IMPORTANCE

Persistent patent ductus arteriosus (PDA) in preterm infants is associated with increased mortality and respiratory morbidities, including bronchopulmonary dysplasia (BPD). Despite recent increasing use of noninterventional approaches, no study to our knowledge has yet directly compared the nonintervention vs pharmacologic treatment for mediating PDA closure for decreasing mortality and preventing BPD.

OBJECTIVE

To determine the noninferiority of nonintervention vs oral ibuprofen treatment for PDA in decreasing BPD incidence or death in very preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

A randomized, double-blind, placebo-controlled, noninferiority clinical trial was conducted on preterm infants (gestational age [GA] 23-30 weeks) with hemodynamically significant PDA (ductal size >1.5 mm plus respiratory support) diagnosed between postnatal days 6 and 14. Participants included 383 infants screened between July 24, 2014, and March 15, 2019.

INTERVENTIONS

Infants were stratified by GA and randomly assigned (1:1) to receive either oral ibuprofen (initial dose of 10 mg/kg followed by a 5-mg/kg dose after 24 hours and a second 5-mg/kg dose after 48 hours) or placebo.

MAIN OUTCOMES AND MEASURES

The primary outcome was BPD or death; the secondary outcomes included major morbidities and ductal closure rates. Per-protocol analysis was used.

RESULTS

Among 383 infants screened for participation, 146 infants were randomly assigned, with 72 in the nonintervention and 70 in the ibuprofen treatment group in the final analyses. The PDA closure rate at 1 week after randomization was significantly higher with ibuprofen (11 [34%]) than nonintervention (2 [7%]) in infants at GA 27 to 30 weeks (P = .007); however, the findings were not significant at GA 23 to 26 weeks (ibuprofen, 3 [8%] vs nonintervention, 1 [2%], P = .34). In addition, the ductal closure rates before hospital discharge (ibuprofen, 62 [89%] vs nonintervention, 59 [82%], P = .27) and device closure (ibuprofen, 2 [3%] vs nonintervention, 4 [6%], P = .40) were not significantly different between the 2 groups. The nonintervention approach was noninferior to ibuprofen treatment in terms of BPD incidence or death (nonintervention, 44%; ibuprofen, 50%; 95% CI, -0.11 to 0.22; noninferiority margin -0.2; P = .51). One infant in the ibuprofen arm received oral ibuprofen backup rescue treatment owing to cardiopulmonary compromise refractory to conservative management, and another infant in the ibuprofen group received surgical ligation; none of the infants in the placebo group received backup treatment.

CONCLUSIONS AND RELEVANCE

Nonintervention showed noninferiority compared with ibuprofen treatment in closing of hemodynamically significant PDA and reduction of BPD or death. The noninferiority of nonintervention over ibuprofen might be attributable to the low efficacy of oral ibuprofen for closing PDA, especially in infants born at 23 to 26 weeks' gestation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02128191.

Lung Ultrasound Score Predicts the Extravascular Lung Water Content in Low-Birth-Weight Neonates with Patent Ductus Arteriosus

BACKGROUND Patent ductus arteriosus (PDA) is a common congenital cardiac abnormality in premature infants. In low-birth-weight infants weighing less than 2500 g, if the PDA continues to open, abnormal circulation hemodynamics and pulmonary edema may occur. This study aimed to investigate the role of lung ultrasound score in the assessment of pulmonary edema in low-weight neonates with PDA. MATERIAL AND METHODS Two hundred and twenty-one neonates with low birth weight were selected as the subjects, children with PDA as the observation group, and children with closed ductus arteriosus as the control group. On the fourth postnatal day, lung ultrasound examination and 6-segment lung ultrasound scoring were performed. RESULTS All 221 infants (94 in the observation group, 127 controls) underwent ultrasound examinations of the lungs. Intergroup differences in gestational age, birth weight, length of hospital stay, and left ventricular ejection fraction were not statistically significant. There was a significant difference in lung ultrasound score (t=0.005, P=0.000) and aortic root ratio to left atrial (t=0.085, P=0.000), which was negatively correlated with gestational age (r=-0.235, P=0.000) and positively correlated with PDA diameter (r=0.261, P=0.011). CONCLUSIONS Low-birth-weight children often have PDA. Its continued opening changes the circulation hemodynamics in children. Lung ultrasound score can semi-quantitatively evaluate the extravascular lung water content, identifying the need to intervene and follow up the hemodynamic significance of PDA over time.

Neonatal Intensive Care Unit-Level Patent Ductus Arteriosus Treatment Rates and Outcomes in Infants Born Extremely Preterm

OBJECTIVES

To assess associations between neonatal intensive care unit (NICU)-level patent ductus arteriosus (PDA) treatment rates (pharmacologic or surgical) and neonatal outcomes.

STUDY DESIGN

This cohort study included infants born at 24-28 weeks of gestation and birth weight <1500 g in 2007-2015 in NICUs caring for ≥100 eligible infants in 6 countries. The ratio of observed/expected (O/E) PDA treatment rates was derived for each NICU by estimating the expected rate using a logistic regression model adjusted for potential confounders and network. The primary composite outcome was death or severe neurologic injury (grades III-IV intraventricular hemorrhage or periventricular leukomalacia). The associations between the NICU-level O/E PDA treatment ratio and neonatal outcomes were assessed using linear regression analyses including a quadratic effect (a square term) of the O/E PDA treatment ratio.

RESULTS

From 139 NICUs, 39 096 infants were included. The overall PDA treatment rate was 45% in the cohort (13%-77% by NICU) and the O/E PDA treatment ratio ranged from 0.30 to 2.14. The relationship between the O/E PDA treatment ratio and primary composite outcome was U-shaped, with the nadir at a ratio of 1.13 and a significant quadratic effect (P<.001). U-shaped relationships were also identified with death, severe neurologic injury, and necrotizing enterocolitis.

CONCLUSIONS

Both low and high PDA treatment rates were associated with death or severe neurologic injury, whereas a moderate approach was associated with optimal outcomes.

Changes in Serum Creatinine Levels and Natural Evolution of Acute Kidney Injury with Conservative Management of Hemodynamically Significant Patent Ductus Arteriosus in Extremely Preterm Infants at 23-26 Weeks of Gestation

Changes in kidney function in extremely preterm infants (EPT) with conservatively managed hemodynamically significant (HS) patent ductus arteriosus (PDA) are not known well. We aimed to present the postnatal course in serum creatinine levels (sCr), prevalence of acute kidney injury (AKI), then relevance between AKI and adverse outcomes in EPT with conservatively managed HS PDA. By review of medical records, we analyzed the postnatal course of sCr and prevalence of stage 3 AKI defined by the modified Kidney Disease Improving Global Outcome (KDIGO) in EPT at gestational age of 23 to 26 weeks with conservatively treated HS PDA. We investigated if the presence and/or prolonged duration of stage 3 AKI elevated the risk of adverse outcomes. The results showed that, neither factor was associated with adverse outcomes. While the average PDA closure date was at postnatal day (P) 41 and 53, sCr peaked at P 10 and 14 and the cumulative prevalence of stage 3 AKI was 57% and 72% in the EPT of 25–26 and 23–24 weeks’ gestation, respectively. The high prevalence of stage 3 AKI without adverse outcomes in EPT with conservatively managed HS PDA suggests that it might reflect renal immaturity rather than pathologic conditions.

An Observational, Prospective, Multicenter, Registry-Based Cohort Study Comparing Conservative and Medical Management for Patent Ductus Arteriosus

No consensus has been reached on which patent ductus arteriosus (PDAs) in preterm infants require treatment and if so, how, and when they should be treated. A prospective, multicenter, cohort study was conducted to compare the effects of conservative approaches and medical treatment options on ductal closure at discharge, surgical ligation, prematurity-related morbidities, and mortality. Infants between 24^0/7 and 28^6/7 weeks of gestation from 24 neonatal intensive care units were enrolled. Data on PDA management and patients' clinical characteristics were recorded prospectively. Patients with moderate-to-large PDA were compared. Among the 1,193 enrolled infants (26.7 ± 1.4 weeks and 926 ± 243 g), 649 (54%) had no or small PDA, whereas 544 (46%) had moderate-to-large PDA. One hundred thirty (24%) infants with moderate-to-large PDA were managed conservatively, in contrast to 414 (76%) who received medical treatment. Eighty (62%) of 130 infants who were managed conservatively did not receive any rescue treatment and the PDA closure rate was 53% at discharge. There were no differences in the rates of late-onset sepsis, necrotizing enterocolitis (NEC), retinopathy of prematurity, intraventricular hemorrhage (≥Grade 3), surgical ligation, and presence of PDA at discharge between conservatively-managed and medically-treated infants (p > 0.05). Multivariate analysis including perinatal factors showed that medical treatment was associated with increased risk for mortality (OR 1.68, 95% Cl 1.01-2.80, p = 0.046), but decreased risk for BPD or death (BPD/death) (OR 0.59, 95%Cl 0.37-0.92, p = 0.022). The preferred treatment options were ibuprofen (intravenous 36%, oral 31%), and paracetamol (intravenous 26%, oral 7%). Infants who were treated with oral paracetamol had higher rates of NEC and mortality in comparison to other treatment options. Infants treated before postnatal day 7 had higher rates of mortality and BPD/death than infants who were conservatively managed or treated beyond day 7 (p = 0.009 and 0.007, respectively). In preterm infants born at <29 weeks of gestation with moderate-to-large PDA, medical treatment did not show any reduction in the rates of open PDA at discharge, surgical or prematurity-related secondary outcomes. In addition to the high incidence of spontaneous closure of PDA in the first week of life, early treatment (<7 days) was associated with higher rates of mortality and BPD/death.

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.

Duration of significant patent ductus arteriosus and bronchopulmonary dysplasia in extremely preterm infants

OBJECTIVE

To demonstrate the association between the duration of significant patent ductus arteriosus (PDA) and bronchopulmonary dysplasia (BPD) in extremely preterm infants.

METHODS

All extremely preterm infants (<29 weeks) treated in our Neonatal Intensive Care Unit from January 2013 to March 2016 were included if their PDA status was confirmed at <7 days of life. Infants with genetic syndromes, complex congenital anomalies and insignificant PDAs were excluded. Total duration of significant PDA was estimated by reviewing serial echocardiograms. Significant PDA was diagnosed using our scoring system that was based upon echocardiographic parameters and clinical status of the infants. Study cohort was divided into four groups based on the duration of significant PDA. Group A-No PDA, Group B-PDA <1-week, Group C- PDA 1-2 weeks, and Group D-PDA >2 weeks. ANOVA and multivariate analysis were performed to compare the groups.

RESULTS

There were 147 infants with no PDA (Group A), 50, 35, and 41 infants were enrolled in Groups B, C, and D, respectively. There were no differences in maternal and neonatal variables among groups except for the following: maternal smoking, chorioamnionitis, antenatal indomethacin, gestation, birth weight, mode of delivery and incidence of death or BPD. Logistic regression analysis showed that longer duration of significant PDA was associated with higher risk for death or BPD (adjusted OR 1.37, 95% CI 1.03-1.82).

CONCLUSION

Longer duration of significant PDA is associated with the higher risk for BPD/death in extremely preterm infants.

Ibuprofen treatment after the first days of life in preterm neonates with patent ductus arteriosus

AIM

Patent ductus arteriosus (PDA) is treated with ibuprofen and it is known that the clearance of ibuprofen increases with postnatal age. We aimed to study whether postnatal age-adjusted ibuprofen dosages improve the effectiveness of treatment compared to standard ibuprofen dosages after the first days of life.

METHODS

A historical cohort of 207 preterm neonates treated with standard ibuprofen dosages (Group A; 2011-2015) was compared to a prospective cohort of 66 preterm neonates treated with postnatal age-adjusted ibuprofen dosages (Group B; 2015-2016).

RESULTS

Both groups had comparable background characteristics. Treatment was started after median 6 (25-75th percentile: 4-11) and 5 (25-75th percentile: 4-11) days and effectiveness was 33.2 and 44.7% (p = .17) in groups A and B, respectively. No hemodynamically significant PDA was found in 23/49 (46.9%) of the patients born before 28 weeks after adjusted ibuprofen dosages compared to 48/162 (29.6%) after standard ibuprofen dosages (p = .04). There were significantly more reversible side effects with the postnatal age-adjusted ibuprofen dosages (p = .04).

CONCLUSIONS

There seems to be a trend to higher effectiveness with the adjusted ibuprofen dosages in preterm neonates before 28 weeks, but it is associated with more reversible side effects.

Early haemodynamically significant patent ductus arteriosus does not predict future persistence in extremely preterm infants

AIM

We assessed whether early haemodynamically significant patent ductus arteriosus (hsPDA) predicted persistent patent ductus arteriosus (PDA) in extremely preterm infants.

METHODS

This prospective observational study of 60 infants born at 22-27 weeks of gestational age (GA) without any major congenital anomalies or heart defects was conducted at Uppsala University Children's Hospital from November 2012 to May 2015. Respiratory and systemic circulatory parameters were continuously recorded, and echocardiographic examinations performed daily during the first three days of life. Pharmacological treatment was initiated if hsPDA was found on days two to seven. Persistent PDA was diagnosed if hsPDA remained after pharmacological treatment or pharmacological treatment was contraindicated.

RESULTS

The infants (56% male) had a median GA of 25 + 2 weeks and 50% received pharmacological treatment. PDA was persistent in 30% and ultimately closed or insignificant in 70%. hsPDA on days two to seven was not associated with future persistent PDA (p = 1.000). Mechanical ventilation (p = 0.025), high mean airway pressure (p = 0.020) and low ductal maximal flow velocity (V_max ) (p = 0.024) on day two were associated with future persistent PDA.

CONCLUSION

Early hsPDA did not predict persistent PDA, but the early need for assisted ventilation and low ductal V_max were associated with future persistent PDA in these extremely preterm infants.

Understanding the Pathophysiology, Implications, and Treatment Options of Patent Ductus Arteriosus in the Neonatal Population

BACKGROUND

Patent ductus arteriosus (PDA) is the persistence of a fetal shunt between the pulmonary artery and the aorta. This structure normally closes in the first 3 days after birth; however, closure is delayed in up to 80% of infants born at 25 to 28 weeks of gestation. Persistent PDA results in pulmonary overcirculation and systemic hypoperfusion.

PURPOSE

The purpose of this article is to review pathophysiology and treatment options for PDA.

METHODS

A literature review was conducted using PubMed, CINAHL, and Google Scholar (2013-2018). Search terms included neonate, PDA, pathophysiology, pharmacotherapy, nursing, ligation, indomethacin, ibuprofen, and acetaminophen (paracetamol).

RESULTS

Optimal treatment remains contentious. Options include conservative/medical, pharmacologic, and surgical management. Conservative/medical management includes mild fluid restriction, increased airway pressures, and supportive care. Pharmacologic treatment is accomplished using indomethacin, ibuprofen, or acetaminophen. Surgical intervention is by direct closure or by percutaneous ligation. Treatment may be prophylactic, presymptomatic, or symptomatic. Long-term morbidities associated with PDA include chronic lung disease, retinopathy of prematurity, and neurodevelopmental delay.

IMPLICATIONS FOR RESEARCH

Absence of a universal scoring system for severity of PDA limits accuracy of comparisons among research studies. Lack of a consistent definition also makes it difficult to aggregate data for meta-analyses. Adoption of a consistent scoring system for hemodynamic significance would facilitate comparisons of outcomes among research studies.

IMPLICATIONS FOR PRACTICE

Clinicians should be aware of treatment options for PDA and their implications on neonatal outcomes. For nurses, anticipation of possible side effects is important for performance of focused assessments.

Practice for preterm patent ductus arteriosus; focusing on the hemodynamic significance and the impact on the neonatal outcomes

Hemodynamically significant preterm patent ductus arteriosus (PDA) affects mortality; comorbidities such as necrotizing enterocolitis, intraventricular hemorrhage, and bronchopulmonary dysplasia; and adverse long-term neurodevelopmental outcomes in preterm infants, particularly in very low birth weight infants. However, recent studies have indicated that there is no consensus on the causal relationship between PDA and neonatal outcomes, the benefit of PDA treatment, the factors guiding the need for treatment, and optimal treatment strategies. Such uncertainty has resulted in wide variations in practice for treating preterm PDA between units, regions, and nations. Nowadays, there has been a paradigm shift to more conservative treatment for preterm PDA, and suggestions regarding selective management of preterm PDA considering risk factors and hemodynamic significance are increasing. Neonatologist-performed echocardiography and advances in modalities to assess hemodynamic significance such as biologic markers and near-infrared spectroscopy also help improve the efficacy of selective treatment of preterm PDA.

Genetic variants associated with patent ductus arteriosus in extremely preterm infants

OBJECTIVE

Patent ductus arteriosus (PDA) is a commonly observed condition in preterm infants. Prior studies have suggested a role for genetics in determining spontaneous ductal closure. Using samples from a large neonatal cohort we tested the hypothesis that common genetic variations are associated with PDA in extremely preterm infants.

STUDY DESIGN

Preterm infants (n = 1013) enrolled at NICHD Neonatal Research Network sites were phenotyped for PDA. DNA was genotyped for 1634 single nucleotide polymorphisms (SNPs) from candidate genes. Analyses were adjusted for ancestral eigenvalues and significant epidemiologic variables.

RESULTS

SNPs in several genes were associated with the clinical diagnosis of PDA and with surgical ligation in extremely preterm neonates diagnosed with PDA (p < 0.01). None of the associations were significant after correction for multiple comparisons.

CONCLUSION

We identified several common genetic variants associated with PDA. These findings may inform further studies on genetic risk factors for PDA in preterm infants.

Evaluation of factors for poor outcome in preterm newborns with posthemorrhagic hydrocephalus associated with late-onset neonatal sepsis

Purpose

Preterm newborns, due to many factors, are at increased risk for poor neural development, intraventricular hemorrhages, infections, and higher rate of mortality. The aim of this study was to evaluate the risk factors associated with poor outcome in preterm neonates with late-onset neonatal sepsis (LONS) who had posthemorrhagic hydrocephalus and underwent neurosurgical procedures for treatment of the hydrocephalus.

Patients and methods

Preterm neonates who had undergone insertion of ventriculoperitoneal shunt or Ommaya reservoir, during the 10-year period at University Children's Hospital, were retrospectively analyzed. According to the presence or absence of LONS, patients were divided into LONS group and non-LONS group. In both groups, we analyzed demographic and clinical data as well as nondependent factors. Additionally, we evaluated the patients who had lethal outcome in respect to all the analyzed factors.

Results

A total of 74 patients were included in the study, 35 in LONS group and 39 in control group. Patients in LONS group were born significantly earlier with lower birth weight, needed significantly higher O₂ inspiratory concentration, and had longer duration of mechanical ventilation when compared to the nonseptic group. Five patients in LONS group had lethal outcome, and for these patients we identified a grade American Society of Anaesthesiologists score of 4 (P=0.000), ductus arteriosus persistens (P=0.000), bronchopulmonary dysplasia (P=0.003), and pneumothorax (P=0.003) as independent preoperative risk factors for lethal outcome.

Conclusion

Neurosurgical procedures are relatively safe in neonates with posthemorrhagic hydrocephalus without LONS after birth. However, if LONS is present, various conditions such as preoperative high grade American Society of Anaesthesiologists score, ductus arteriosus persistens, bronchopulmonary dysplasia, and pneumothorax markedly increase the risk for a lethal outcome after the operation.

Early treatment versus expectative management of patent ductus arteriosus in preterm infants: a multicentre, randomised, non-inferiority trial in Europe (BeNeDuctus trial)

BACKGROUND

Much controversy exists about the optimal management of a patent ductus arteriosus (PDA) in preterm infants, especially in those born at a gestational age (GA) less than 28 weeks. No causal relationship has been proven between a (haemodynamically significant) PDA and neonatal complications related to pulmonary hyperperfusion and/or systemic hypoperfusion. Although studies show conflicting results, a common understanding is that medical or surgical treatment of a PDA does not seem to reduce the risk of major neonatal morbidities and mortality. As the PDA might have closed spontaneously, treated children are potentially exposed to iatrogenic adverse effects. A conservative approach is gaining interest worldwide, although convincing evidence to support its use is lacking.

METHODS

This multicentre, randomised, non-inferiority trial is conducted in neonatal intensive care units. The study population consists of preterm infants (GA < 28 weeks) with an echocardiographic-confirmed PDA with a transductal diameter > 1.5 mm. Early treatment (between 24 and 72 h postnatal age) with the cyclooxygenase inhibitor (COXi) ibuprofen (IBU) is compared with an expectative management (no intervention intended to close a PDA). The primary outcome is the composite of mortality, and/or necrotising enterocolitis (NEC) Bell stage ≥ IIa, and/or bronchopulmonary dysplasia (BPD) defined as the need for supplemental oxygen, all at a postmenstrual age (PMA) of 36 weeks. Secondary outcome parameters are short term sequelae of cardiovascular failure, comorbidity and adverse events assessed during hospitalization and long-term neurodevelopmental outcome assessed at a corrected age of 2 years. Consequences regarding health economics are evaluated by cost effectiveness analysis and budget impact analysis.

DISCUSSION

As a conservative approach is gaining interest, we investigate whether in preterm infants, born at a GA less than 28 weeks, with a PDA an expectative management is non-inferior to early treatment with IBU regarding to the composite outcome of mortality and/or NEC and/or BPD at a PMA of 36 weeks.

TRIAL REGISTRATION

This trial is registered with the Dutch Trial Register NTR5479 (registered on 19 October 2015), the registry sponsored by the United States National Library of Medicine Clinicaltrials.gov NCT02884219 (registered May 2016) and the European Clinical Trials Database EudraCT 2017-001376-28 .

Non-pharmacological management of a hemodynamically significant patent ductus arteriosus

The association between the patent ductus arteriosus (PDA) and neonatal morbidity, mortality and poor neurodevelopmental outcome in later childhood has been the focus of intense debate for decades. The lack of evidence supporting therapeutic strategies aimed at achieving PDA closure has led to the widespread adoption of conservative management aimed at mitigating the impact of shunt volume without achieving ductal closure. In this article, we review this management approach, describe the supportive evidence and potential complications associated with this strategy.

The dark side of ibuprofen in the treatment of patent ductus arteriosus: could paracetamol be the solution?

INTRODUCTION

Patent ductus arteriosus (PDA) persistence is associated, in prematures, to several complications. The optimal PDA management is still under debate, especially regarding the best therapeutic approach and the time to treat. The available drugs are not exempt from contraindications and side effects; ibuprofen itself, although representing the first-choice therapy, can show nephrotoxicity and other complications. Paracetamol seems a valid alternative to classic nonsteroidal anti-inflammatory Drugs, with a lower toxicity. Areas covered: Through an analysis of the published literature on ibuprofen and paracetamol effects in preterm neonates, this review compares the available treatments for PDA, analyzing the mechanisms underlining ibuprofen-associated nephrotoxicity and the eventual paracetamol-induced hepatic damage, also providing an update of what has been yet demonstrated and a clear description of the still open issues. Expert Opinion: Paracetamol is an acceptable alternative in case of contraindication to ibuprofen; its toxicity, in this setting, is very low. Lower doses may be effective, with even fewer risks. In the future, paracetamol could represent an efficacious first-line therapy, although its safety, optimal dosage, and global impact have to be fully clarified through long-term trials, also in the perspective of an individualized and person-based therapy taking into account the extraordinary individual variability.

Catheter-based closure of the patent ductus arteriosus in lower weight infants

Risks associated with drug therapy and surgical ligation have led health care providers to consider alternative strategies for patent ductus arteriosus (PDA) closure. Catheter-based PDA closure is the procedure of choice for ductal closure in adults, children, and infants ≥6kg. Given evidence among older counterparts, interest in catheter-based closure of the PDA in lower weight (<6kg) infants is growing. Among these smaller infants, the goals of this review are to: (1) provide an overview of the procedure; (2) review the types of PDA closure devices; (3) review the technical success (feasibility); (4) review the risks (safety profile); (5) discuss the quality of evidence on procedural efficacy; (6) consider areas for future research. The review provided herein suggests that catheter-based PDA closure is technically feasible, but the lack of comparative trials precludes determination of the optimal strategy for ductal closure in this subgroup of infants.

Association of Placebo, Indomethacin, Ibuprofen, and Acetaminophen With Closure of Hemodynamically Significant Patent Ductus Arteriosus in Preterm Infants: A Systematic Review and Meta-analysis

IMPORTANCE

Despite increasing emphasis on conservative management of patent ductus arteriosus (PDA) in preterm infants, different pharmacotherapeutic interventions are used to treat those developing a hemodynamically significant PDA.

OBJECTIVES

To estimate the relative likelihood of hemodynamically significant PDA closure with common pharmacotherapeutic interventions and to compare adverse event rates.

DATA SOURCES AND STUDY SELECTION

The databases of MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched from inception until August 15, 2015, and updated on December 31, 2017, along with conference proceedings up to December 2017. Randomized clinical trials that enrolled preterm infants with a gestational age younger than 37 weeks treated with intravenous or oral indomethacin, ibuprofen, or acetaminophen vs each other, placebo, or no treatment for a clinically or echocardiographically diagnosed hemodynamically significant PDA.

DATA EXTRACTION AND SYNTHESIS

Data were independently extracted in pairs by 6 reviewers and synthesized with Bayesian random-effects network meta-analyses.

MAIN OUTCOMES AND MEASURES

Primary outcome: hemodynamically significant PDA closure; secondary: included surgical closure, mortality, necrotizing enterocolitis, and intraventricular hemorrhage.

RESULTS

In 68 randomized clinical trials of 4802 infants, 14 different variations of indomethacin, ibuprofen, or acetaminophen were used as treatment modalities. The overall PDA closure rate was 67.4% (2867 of 4256 infants). A high dose of oral ibuprofen was associated with a significantly higher odds of PDA closure vs a standard dose of intravenous ibuprofen (odds ratio [OR], 3.59; 95% credible interval [CrI], 1.64-8.17; absolute risk difference, 199 [95% CrI, 95-258] more per 1000 infants) and a standard dose of intravenous indomethacin (OR, 2.35 [95% CrI, 1.08-5.31]; absolute risk difference, 124 [95% CrI, 14-188] more per 1000 infants). Based on the ranking statistics, a high dose of oral ibuprofen ranked as the best pharmacotherapeutic option for PDA closure (mean surface under the cumulative ranking [SUCRA] curve, 0.89 [SD, 0.12]) and to prevent surgical PDA ligation (mean SUCRA, 0.98 [SD, 0.08]). There was no significant difference in the odds of mortality, necrotizing enterocolitis, or intraventricular hemorrhage with use of placebo or no treatment compared with any of the other treatment modalities.

CONCLUSIONS AND RELEVANCE

A high dose of oral ibuprofen was associated with a higher likelihood of hemodynamically significant PDA closure vs standard doses of intravenous ibuprofen or intravenous indomethacin; placebo or no treatment did not significantly change the likelihood of mortality, necrotizing enterocolitis, or intraventricular hemorrhage.

TRIAL REGISTRATION

PROSPERO Identifier: CRD42015015797.

Association between early echocardiography, therapy for patent ductus arteriosus, and outcomes in very low birth weight infants

BACKGROUND

In very low birth weight infants, persistence of a patent ductus arteriosus results in morbidity and mortality. Therapies to close the ductus are effective, but clinical outcomes may depend on the accuracy of diagnosis and the timing of administration. The objective of the present study was to characterise the association between early echocardiography, therapy for patent ductus arteriosus, and outcomes in very low birth weight infants.

METHODS

This retrospective cohort study used electronic health record data on inborn infants of gestational age ⩽28 weeks and birth weight <1500 g who were discharged after day of life 7 from 362 neonatal ICU from 1997 to 2013. The primary outcome was death between day of life 7 and discharge. Secondary outcomes included bronchopulmonary dysplasia, necrotising enterocolitis, and grade 3 or 4 intraventricular haemorrhage.

RESULTS

This study included a total of 48,551 infants with a median gestational age of 27 weeks (interquartile range 25, 28) and birth weight 870 g (706, 1050). Early echocardiography - that is, performed during days of life 2 to 6 - was performed in 15,971/48,551 (33%) infants, and patent ductus arteriosus was diagnosed in 31,712/48,551 (65%). The diagnosis was more common in infants who had undergone early echocardiography (14,549/15,971 [91%] versus 17,163/32,580 [53%], p<0.001). In multivariable analysis, early echocardiography was not associated with reduced mortality (odds ratio 0.97, 95% CI 0.89-1.05). Results were similar in the subset of infants who received therapy for patent ductus arteriosus (odds ratio 1.01, 95% CI 0.90-1.15).

CONCLUSIONS

Early echocardiography was associated with an increased diagnosis of patent ductus arteriosus, but not with decreased mortality.

The use of non-steroidal anti-inflammatory drugs for patent ductus arteriosus closure in preterm infants

Over the last four decades, non-steroidal anti-inflammatory drugs have been widely used to induce closure of the patent ductus arteriosus (PDA) in preterm infants. Evidence to support this practice is lacking, despite performance of >50 randomized trials. The credibility of those trials may have been compromised by high rates of open treatment in controls, era of study prior to advent of modern practices, or inclusion of insufficient numbers of very immature infants. Meta-analyses show little impact of those factors on main conclusions. Essentially all trials reporting important long-term outcomes (other than mortality) initiated treatment within five days after birth, so no evidence regarding later treatment is available. Accruing clinical experience suggests that long-term outcomes are not compromised, and may be improved, with non-interventional management strategies. Future studies to identify preterm infants at greatest risk of potential harm from a persistent PDA, particularly after the second postnatal week, are urgently needed.

Transcatheter Occlusion of the Patent Ductus Arteriosus in 747 Infants <6 kg: Insights From the NCDR IMPACT Registry

OBJECTIVES

The authors sought to identify risk factors associated with major adverse events (MAEs) in infants <6 kg undergoing transcatheter patent ductus arteriosus (PDA) occlusion.

BACKGROUND

Transcatheter PDA occlusion is among the safest of interventional cardiac procedures in adults and older children, but use among infants <6 kg has not been characterized adequately.

METHODS

Using the IMPACT (IMproving Pediatric and Adult Congenital Treatments) registry, we identified infants <6 kg undergoing transcatheter PDA occlusion (January 1, 2011, to March 1, 2015). Using mixed-effects multivariate regression, the authors assessed characteristics predictive of MAE or composite failure (procedural failure or MAE). Individual safety metrics (e.g., embolization, malposition) were also examined for differences across weight thresholds: extremely low weight (LW) (<2 kg), very LW (2 to <4 kg), and LW (4 to <6 kg).

RESULTS

Transcatheter PDA occlusion was attempted in 747 infants <6 kg at 73 hospitals. Rate of procedural success was 94.3%. MAEs were observed in 12.6% of cases; the most common events were acute arterial injury and device embolization in 3.5% and 2.4% of cases, respectively. Younger age (<30 days) was associated with greater risk of a MAE (risk ratio: 3.3; 95% confidence interval: 1.5 to 7.6) and composite failure (risk ratio: 3.0; 95% confidence interval: 1.4 to 6.7). Risk of embolization was higher among extremely LW (10.5%) than very LW or LW infants (1.6% and 2.5%, respectively; p = 0.050).

CONCLUSIONS

Among infants <6 kg, transcatheter PDA occlusion is technically feasible, but risks of MAE are noteworthy. These findings may help inform patient selection and procedural approach for transcatheter PDA occlusion and direct targeted research efforts to support the practice of evidence-based medicine.

Paracetamol in Patent Ductus Arteriosus Treatment: Efficacious and Safe?

In preterm infants, failure or delay in spontaneous closure of Ductus Arteriosus (DA), resulting in the condition of Patent Ductus Arteriosus (PDA), represents a significant issue. A prolonged situation of PDA can be associated with several short- and long-term complications. Despite years of researches and clinical experience on PDA management, unresolved questions about the treatment and heterogeneity of clinical practices in different centers still remain, in particular regarding timing and modality of intervention. Nowadays, the most reasonable strategy seems to be reserving the treatment only to hemodynamically significant PDA. The first-line therapy is medical, and ibuprofen, related to several side effects especially in terms of nephrotoxicity, is the drug of choice. Administration of oral or intravenous paracetamol (acetaminophen) recently gained attention, appearing effective as traditional nonsteroidal anti-inflammatory drugs (NSAIDs) in PDA closure, with lower toxicity. The results of the studies analyzed in this review mostly support paracetamol efficacy in ductal closure, with inconstant low and transient elevation of liver enzymes as reported side effect. However, more studies are needed to confirm if this therapy shows a real safety profile and to evaluate its long-term outcomes, before considering paracetamol as first-choice drug in PDA treatment.