What happens when the patent ductus arteriosus is treated less aggressively in very low birth weight infants?

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.

Trends in patent ductus arteriosus ligation in neonates and changes in outcomes: A 10-year multicenter experience

RATIONALE

The management of neonates with patent ductus arteriosus (PDA) has changed over time.

METHODS

We conducted a single-city, retrospective review of neonates who underwent PDA ligation over a 10-year time period and compared infants from the first 5 years to the second 5 years to evaluate how clinical characteristics changed over this time.

RESULTS

Infants from the second 5-year epoch were older at time of ligation (38 vs. 30 days), had a higher ligation weight (1432 vs. 1121 g) and a lower incidence of postligation cardiac syndrome (1.9% vs. 11.5%). No differences in mortality, length of hospital-stay or major morbidities were seen. Compared to neonates who underwent PDA ligation at ≤28 days of life, those with a ligation age >28 days had a higher ligation weight (1421 vs. 1039 g), a higher proportion of COX inhibitor use (92.5% vs. 83.8%), and a higher incidence of moderate-severe bronchopulmonary dysplasia (BPD) (60.4% vs. 44.4%). Only 10.7% (25/233) patients were evaluated by laryngoscopy, in which the incidence of vocal cord paralysis (VCP) was 36.0%; 2 patients were clinically diagnosed with VCP for a total 4.7% incidence of VCP (11/233).

CONCLUSIONS

Over the 10 years examined, neonates underwent PDA ligation at an older age in the second 5-year time period; this change was not associated with a change in the incidence of major morbidities. Ligation age >28 days was associated with an increase incidence of moderate-severe BPD. The overall incidence of documented VCP post-PDA ligation was relatively low but was seen in over 1/3 who were evaluated by laryngoscopy.

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.

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.

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.

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.

Outcomes in infants < 29 weeks of gestation following single-dose prophylactic indomethacin

BACKGROUND

Prophylactic indomethacin (3 doses) decreases patent ductus arteriosus (PDA) and intraventricular hemorrhage (IVH) in preterm infants. The study aim was to determine whether single-dose indomethacin (SD-INDO) decreases PDA, IVH, and improves motor function.

METHODS

A retrospective cohort (2007-2014) compared infants born < 29 weeks who did (n = 299) or did not (n = 85) receive SD-INDO and estimated outcomes association with ordinal logistic regression, adjusting for multiple variables using propensity scores.

RESULTS

Infants who received SD-INDO were more premature (p < 0.001) but had lower odds of PDA (OR 0.26 [0.15, 0.44], p < 0.005), PDA receiving treatment (OR 0.12 [0.03, 0.47], p < 0.005), death (OR 0.41 [0.20, 0.86], p = 0.02), and CP severity (OR 0.33 [0.12, 0.89], p = 0.03). There was less IVH (OR 0.58 [0.36, 0.94], p = 0.03) when adjusted for gestational age.

CONCLUSIONS

SD-INDO is associated with decreased PDA and CP severity and improved survival.

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.

Intravenous paracetamol in comparison with ibuprofen for the treatment of patent ductus arteriosus in preterm infants: a randomized controlled trial

Our aim was to assess the efficacy and safety of intravenous (i.v.) paracetamol vs. i.v. ibuprofen for the treatment of hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. This is a multicenter randomized controlled study. Infants with a gestational age of 25⁺⁰-31⁺⁶ weeks were randomized to receive i.v. paracetamol (15 mg/kg/6 h for 3 days) or i.v. ibuprofen (10-5-5 mg/kg/day). The primary outcome was the closure rate of hsPDA after the first treatment course with paracetamol or ibuprofen. Secondary outcomes included the constriction rate of hsPDA, the re-opening rate, and the need for surgical closure. Fifty-two and 49 infants received paracetamol or ibuprofen, respectively. Paracetamol was less effective in closing hsPDA than ibuprofen (52 vs. 78%; P = 0.026), but the constriction rate of the ductus was similar (81 vs. 90%; P = 0.202), as confirmed by logistic regression analysis. The re-opening rate, the need for surgical closure, and the occurrence of adverse effects were also similar.Conclusions: Intravenous paracetamol was less effective in closing hsPDA than ibuprofen, but due to a similar constriction effect, its use was associated with the same hsPDA outcome. These results can support the use of i.v. paracetamol as a first-choice drug for the treatment of hsPDA.Trial registration: Clinicaltrials.gov : NCT02422966, Date of registration: 04/09/2015; EudraCT no: 2013-003883-30. What is Known: • The successful closure of patent ductus arteriosus with oral paracetamol has been recently reported in several preterm infants, but only one randomized controlled study investigated the efficacy of intravenous paracetamol. What is New: • Intravenous paracetamol is less effective in closing hsPDA than ibuprofen, but have a similar constriction effect. • These results can support the use of i.v. paracetamol as a first-choice drug for the treatment of hsPDA.

Patent ductus arteriosus and oxidative stress in preterm infants: a narrative review

The role of oxygen, reactive oxygen species (ROS), and isoprostanes (IsoPs) in regulating patency and closure of patent ductus arteriosus (PDA) have been studied in preterm infants. Also the possible correlation between a hemodynamically significant PDA and its pharmacological treatment with oxidative stress has been investigated. The National Library of Medicine (MEDLINE) database was searched without time limits. Available data demonstrate that free radicals are not always harmful and that ROS and IsoPs play a relevant role in DA closure. On the other hand, a hemodynamically significant PDA can cause oxidative stress and this can partially explain its association with other complications of prematurity related to oxidative stress, such as bronchopulmonary dysplasia (BPD), intraventricular haemorrhage (IVH), and necrotizing enterocolitis (NEC). Some drugs used for pharmacological closure, such as ibuprofen, also have antioxidant effects, and the closure of PDA can restore a proper tissue oxygenation and the balance between pro-oxidant and antioxidant factors. These data support the importance of the relationship between PDA and oxidative stress whose understanding increase our awareness when we approach this prematurity complication in the clinical practice. Further studies might assess the reliability of ROS as possible biomarkers of the risk of developing a hsPDA.

Risk factors associated with prolonged mechanical ventilation after surgical patent ductus arteriosus ligation in preterm infants

BACKGROUND

One of the main pathophysiologies of a hemodynamically significant patent ductus arteriosus (hsPDA) involves pulmonary over-circulation. However, PDA treatment does not present with uniform effects on pulmonary outcomes. We aimed to evaluate the clinical characteristics - in particular, respiratory parameters - associated with prolonged mechanical ventilation after PDA ligation.

METHODS

Preterm infants ≤32 weeks gestation were included in the study. Infants who underwent PDA ligation were grouped depending on whether the infant successfully was extubated ≤14 d after ligation or required prolonged invasive mechanical ventilation >14 d after ligation. The clinical characteristics, including the parameters concerning the respiratory illness severity and hemodynamical significance of PDA shunt, were compared between the two groups.

RESULTS

Among 172 preterm infants, 36 (20.9%) infants underwent surgical PDA ligation. Fifteen (41.6%) infants were successfully extubated at ≤14 d after ligation, and 21 (58.3%) infants required prolonged invasive mechanical ventilation for >14 d after ligation. In the univariable analysis, the infants who required prolonged mechanical ventilation was significantly smaller in terms of gestational age (GA) and birth weight and tended to present a greater respiratory illness severity [represented by the use of high-frequency oscillatory ventilation (HFOV) and greater RSS (respiratory severity score)/kg] with a larger PDA size prior to PDA ligation. In the multivariable logistic regression analysis, peak preoperative RSS/kg (p = 0.012, OR = 0.207, 95% CI = 0.060-0.706) was the only significant factor associated with prolonged mechanical ventilation after PDA ligation.

CONCLUSION

Preterm infants with the compromised respiratory condition may be prone to prolonged mechanical ventilation after PDA ligation. The respiratory status during the early phase of life should be considered when evaluating the effect of PDA treatment. With an extended view, distinguishing infants with such risk factors may lead to more polished treatment strategies toward hsPDA.

Patent ductus arteriosus and cerebral, cardiac, and gut hemodynamics in premature neonates

Patent ductus arteriosus is associated with multiple comorbidities in premature infants, however a causal link or strategy to decrease these morbidities has not been found. The association between the patent ductus arteriosus and morbidities has biologic plausibility as, like any cardiac mixing lesion, a significant systemic to pulmonic shunt may lead to pulmonary over-circulation and systemic hypoperfusion. Understanding the underlying pathophysiology of associated morbidities in the setting of a patent ductus arteriosus may aid in risk stratifying infants and offer a patient targeted approach to infants with a pathological ductal shunt. While the deleterious impact of increased pulmonary blood flow maybe easier to identify, the impact on end-organ perfusion is more challenging. In this review, we will discuss the pathophysiology of a hemodynamically significant patent ductus arteriosus in premature infants, impact on end-organ perfusion and associated morbidities, and novel modalities to assess shunt volume and effect on end-organ perfusion.

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.

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.

Survey of PDA management in very low birth weight infants across Italy

Background

The optimal management of PDA in very low birth weight (VLBW) infants is still controversial. Aim of our study was to investigate the management of PDA in the Italian neonatal intensive care units (NICU).

Methods

We conducted an on-line survey study from June to September 2017. A 50-items questionnaire was developed by the Italian Neonatal Cardiology Study Group and was sent to Italian NICUs.

Results

The overall response rate was 72%. Diagnosis of PDA was done by neonatologists, cardiologists or both (62, 12 and 28% respectively). PDA significance was assessed by a comprehensive approach in all centers, although we found a heterogeneous combination of parameters and cut-offs used. None used prophylactic treatment. 19% of centers treated PDA in the first 24 h, 60% after the first 24 h, following screening echocardiography or clinical symptoms, 18% after the first 72 h and 2% after the first week. In the first course of treatment ibuprofen, indomethacin and paracetamol were used in 87, 6 and 7% of centers respectively. Median of surgical ligation was 3% (1–6%).

Conclusions

Significant variations exist in the management of PDA in Italy. Conservative strategy and targeted treatment to infants older than 24 h with echocardiographic signs of hemodynamic significance seemed to be the most adopted approach.

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.

Transcatheter Closure of Patent Ductus Arteriosus in Premature Infants With Very Low Birth Weight

Background: The aim of this study was to describe our experience with transcatheter device closure of patent ductus arteriosus (PDA) in symptomatic low-birth-weight premature infants. Methods: We performed a retrospective study of infants born with a birth body weight of < 2,000 g and admitted to National Cheng Kung University Hospital from September 2014 to December 2019. Basic demographic and clinical information as well as echocardiographic and angiographic data were recorded. Results: Twenty-five premature infants (11 boys and 14 girls) born at gestational ages ranging between 22 and 35 weeks (mean, 25 weeks) were identified. The mean age at procedure was 34.5 ± 5.5 days, and the mean weight was 1,209 ± 94 g (range, 478-1,980 g). The mean diameter of the PDA was 3.4 ± 0.2 mm (range, 2.0-5.4 mm). The following devices were used in this study: Amplatzer Ductal Occluder II additional size (n = 20), Amplatzer Vascular Plug I (n = 1), and Amplatzer Vascular Plug II (n = 4). Complete closure was achieved in all patients. The mean follow-up period was 30.1 ± 17.3 months (range, 6-68 months). In total, 3 patients had left pulmonary artery (LPA) stenosis and 1 patient had coarctation of the aorta during the follow-up period. Younger procedure age and smaller procedure body weight were significantly associated with these obstructions. Conclusions: Performing transcatheter PDA closure in symptomatic premature infants weighing more than 478 g is feasible using currently available devices; moreover, the procedure serves as an alternative to surgery.

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.

Isoprostanes as Biomarker for Patent Ductus Arteriosus in Preterm Infants

Context: It has been reported that isoprostanes (IPs) have a role in the pathophysiology of ductus arteriosus during the fetal and neonatal period. Our aim in this study was to assess if urinary IPs (uIPs) levels correlate with the risk of developing a hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. Materials and methods: Infants with 23 + 0 - 33 + 6 weeks of gestational age and respiratory distress syndrome (RDS) were consecutively enrolled. Urine samples were collected on the 2nd and 10th day of life (DOL) for uIPs measurement. Echocardiography for hsPDA diagnosis was performed between 24 and 48 h of life. Regression analysis was performed to assess the correlation between uIPs and hsPDA. Receiver operating characteristic (ROC) curve analysis was used to evaluate the accuracy of the uIPs in predicting the occurrence of hsPDA. Results: Sixty patients were studied: 33 (55%) developed a hsPDA, 27 (45%) had ibuprofen hsPDA closure, and six (10%) required surgical closure. uIPs levels decreased from the 2nd to the 10th DOL. Adjusted regression analysis demonstrated that uIPs on the 2nd DOL were associated (p = 0.02) with the risk of developing a hsPDA. A cut-off level of 1627 ng/mg of creatinine of uIPs predicted the development of a hsPDA with a sensitivity of 82% and a specificity of 73%. Conclusion: Early measurement of uIPs on the 2nd DOL is a reliable biomarker of hsPDA development and, alone or combined with other markers, might represent a non-invasive tool useful for planning the management of PDA in preterm infants.

Fluid restriction negatively affects energy intake and growth in very low birthweight infants with haemodynamically significant patent ductus arteriosus

AIM

We explored if fluid restriction in very low birthweight (VLBW) infants with a haemodynamically significant patent ductus arteriosus (PDA) affected energy and protein intakes and growth.

METHODS

Retrospectively, we identified 90 VLBW infants that were admitted to Umea University Hospital, Sweden, between 2009 and 2012: 42 with and 48 without haemodynamically significant PDA (hsPDA). Anthropometric, fluid, energy and protein intake data during the first 28 days of life were expressed as z-scores.

RESULTS

In the 42 infants diagnosed with hsPDA, fluid intake was restricted after diagnosis, resulting in a decrease in energy and protein intake. No decrease was observed in the other 48 infants in the cohort. Multivariate analysis showed that the z-score of weight change depended on both ductus arteriosus status and energy intake; thus, infants with hsPDA did not grow as expected with the energy provided to them.

CONCLUSION

Energy and protein intake was diminished in prematurely born infants with hsPDA when fluid was restricted after diagnosis. The initial reduction in intakes may have contributed to the lower postnatal growth observed in these infants.

Lack of Equipoise in the PDA-TOLERATE Trial: A Comparison of Eligible Infants Enrolled in the Trial and Those Treated Outside the Trial

The PDA: TO LEave it alone or Respond And Treat Early trial compared the effects of 2 strategies for treatment of patent ductus arteriosus (PDA) in infants <28^0/7 weeks of gestation; however 137 potentially eligible infants were not recruited and received treatment of their PDA outside the PDA-TOLERATE trial due to "lack-of-physician-equipoise" (LPE). Despite being less mature and needing more respiratory support, infants with LPE had lower rates of mortality than enrolled infants. Infants with LPE treated before day 6 had lower rates of late respiratory morbidity than infants with LPE treated ≥day 6. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01958320.

Indomethacin dosing strategy and neonatal patent ductus arteriosus closure

BACKGROUND

Few studies exist that have evaluated the effects of indomethacin dosing frequency as a factor associated with successful patent ductus arteriosus closure in very low birth weight neonates. The objective of this study is to determine if indomethacin dosing strategy is associated with efficacy for initial patent ductus arteriosus management in very low birth weight neonates.

METHODS

This retrospective review compared every 12 hour and every 24 hour indomethacin regimens primarily for efficacy in initial patent ductus arteriosus management, defined as an absence of repeat medical and/or surgical treatment, and secondarily for safety in both univariate and multivariate models.

RESULTS

One hundred three very low birth weight neonates were included: 56 (54%) received every 12 hour and 47 (46%) underwent every 24 hour indomethacin dosing. Repeat medical and/or surgical patent ductus arteriosus treatment rates were similar between groups. Less ligation of the patent ductus arteriosus occurred with every 12 hour versus every 24 hour dosing (11% vs. 26%, p = 0.05), though this effect was mitigated controlling for birth weight and gestational age. Renal function, respiratory outcomes, feeding outcomes, length of stay, and mortality were similar between groups.

CONCLUSIONS

Neither the every 12 hour nor the every 24 hour indomethacin regimen demonstrated inferior efficacy or safety for initial management of patent ductus arteriosus. Further prospective analysis of indomethacin dosing strategy is warranted.

Patent ductus arteriosus in preterm infants born at 23-24 weeks' gestation: Should we pay more attention?

BACKGROUND

Infants born at 23-24 weeks' gestation have the highest risk of developing a hemodynamically significant patent ductus arteriosus (hsPDA), that is refractory to pharmacological closure requiring surgical ligation. Thus, these patients might have the greatest benefits from hsPDA closure, although previous studies on PDA closure were not focused on this population.

AIM

To compare the occurrence of hsPDA, failure rate of the first course of ibuprofen in closing hsPDA, and need of surgical closure in infants born at 23⁺⁰-24⁺⁶ weeks' gestation to those in infants born at 25⁺⁰-28⁺⁶ weeks' gestation.

STUDY DESIGN

This is a retrospective multicenter study including infants born at 23⁺⁰-28⁺⁶ weeks of gestation admitted to the neonatal care units from January 2013 to December 2017. All infants underwent echocardiographical assessment for hsPDA diagnosis and eventually pharmacological treatment, and surgical closure.

RESULTS

We studied a total of 842 infants of which 562 (67%) developed a PDA. Among those with PDA, 511 (91%) received a pharmacological treatment for a hsPDA. We found that a hsPDA occurred in 70% (106/151) of infants born at 23-24 weeks and in 59% (405/691) of infants born at 25-28 weeks of gestation (P < 0.001). Failure of closure with the first-treatment cycle (69 vs. 40%; P < 0.001) and need of surgical closure (19 vs 10%) were more frequent (P < 0.011) in infants born at 23-24 than 25-28 gestational weeks. Paracetamol vs. ibuprofen treatment and gestational age of 23-24 versus 25-28 weeks increased closure failure, while less severe RDS and maternal clinical chorioamnionitis decreased it.

CONCLUSIONS

Among extremely preterm infants, infants born at 23-24 weeks of gestation have the highest risk of developing a hsPDA refractory to pharmacological treatment requiring surgical closure. Our findings support the need of individualized more careful strategies for hsPDA management in this special population.

Natural evolution of ductus arteriosus with noninterventional conservative management in extremely preterm infants born at 23-28 weeks of gestation

This study aimed to determine the natural course of patent ductus arteriosus (PDA) with noninterventional conservative management and whether the presence and/or prolonged duration of hemodynamically significant (HS) PDA increased the risk of mortality and morbidities in extremely preterm (EPT) infants. We retrospectively reviewed the medical records of EPT infants born at 23-28 weeks of gestation (n = 195) from January 2011 to June 2014, when PDA was managed with noninterventional conservative treatment. We stratified infants into three subgroups of 23-24, 25-26, and 27-28 weeks and analyzed the prevalence and natural evolution of HS PDA, defined as ventilator dependency and PDA size ≥2 mm. Multivariate regression analyses determined if the presence and/or prolonged duration of HS PDA increased the risk for mortality and/or morbidities. The overall incidence of HS PDA was 57% (111/195) at the end of the first postnatal week. In subgroup analyses, infants with 23-24 weeks of gestation had the highest incidence (93%, 50/54), with 64% (47/74) for 25-26 weeks and 21% (14/67) for 27-28 weeks. Six (5%) of 111 infants with HS PDA were discharged without ductus closure, 4 had spontaneous PDA closure on follow up, and device closure was performed for 2 infants. In the multivariate analyses, the presence or prolonged duration (per week) of HS PDA was not associated with the risk of mortality and/or morbidities. Spontaneous closure of HS PDA was mostly achieved, even in EPT infants, with a noninterventional conservative approach. In conclusion, our data showed the incidence and natural course of HS PDA in EPT infants and suggested that the presence or prolonged duration of HS PDA might not increase the rate of mortality or morbidities.

Covariation of Neonatal Intensive Care Unit-Level Patent Ductus Arteriosus Management and In-Neonatal Intensive Care Unit Outcomes Following Preterm Birth

OBJECTIVE

To test the hypothesis that neonatal intensive care unit (NICU)-specific changes in patent ductus arteriosus (PDA) management are associated with changes in local outcomes in preterm infants.

STUDY DESIGN

This retrospective repeated-measures study of aggregated data included infants born 400-1499 g admitted within 2 days of delivery to NICUs participating in the California Perinatal Quality Care Collaborative. The period 2008-2015 was divided into four 2-year epochs. For each epoch and NICU, we calculated proportions of infants receiving cyclooxygenase inhibitor (COXI) or PDA ligation and determined NICU-specific changes in these therapies between consecutive epochs. Generalized estimating equations were used to examine adjusted relationships between NICU-specific changes in PDA management and contemporaneous changes in local outcomes.

RESULTS

We included 642 observations of interepoch change at 119 hospitals summarizing 32 094 infants. NICU-specific changes in COXI use and ligation showed significant dose-response associations with contemporaneous changes in adjusted local outcomes. Each percentage point decrease in NICU-specific proportion treated with either COXI or ligation was associated with a 0.21 percentage point contemporaneous increase in adjusted local in-hospital mortality (95% CI 0.06, 0.33; P = .005) among infants born 400-749 g. In contrast, decreasing NICU-specific ligation rate among infants 1000-1499 g was associated with decreasing adjusted local bronchopulmonary dysplasia (P = .009) and death or bronchopulmonary dysplasia (P = .01).

CONCLUSIONS

NICU-specific outcomes of preterm birth co-vary with local PDA management. Treatment for PDA closure may benefit some infants born 400-749 g. Decreasing NICU-specific rates of COXI use or ligation were not associated with increases in local adjusted rates of examined adverse outcomes in larger preterm infants.

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 .

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.

Patent Ductus Arteriosus in Preterm Infants, Part 1: Understanding the Pathophysiologic Link Between the Patent Ductus Arteriosus and Clinical Complications

The clinical guidelines for treating patent ductus arteriosus (PDA) have significantly evolved over the last decades from treating any ductal shunt to more conservative management where only the hemodynamically significant patent ductus arteriosus (HSPDA) is treated. This shift has resulted largely from a lack of evidence from randomized controlled trials supporting a relationship between treating a PDA and improving long-term neonatal outcomes. However, there are many unresolved issues. There is no consensus on the precise definition of HSPDA requiring treatment or a clear understanding of when to treat HSPDA. Moreover, the current evidence shows worsening of the long-term neurodevelopmental outcome for infants undergoing surgical PDA ligation.<br/> The presence of physiologic variability among preterm infants, and the presence of different compensatory mechanisms may make it difficult to establish a link between pathophysiology and long-term outcomes. That is, the physiologic variability cannot be simply assessed by randomly assigning infants into two arms of a study. Relying on research from animal and human studies, this article explains the link between the pathophysiology of a PDA and neonatal outcomes.

Transcatheter occlusion of the patent ductus arteriosus in premature infants weighing less than 1200 g

OBJECTIVES

Over the last few decades different strategies have been proposed to treat persistent ductal patency in premature infants. The advent of the Amplatzer Duct Occluder II Additional Size (ADOIIAS) provided the potential to close the patent ductus arteriosus (PDA). Opinions differ on the significance and treatment of PDA in premature neonates. Because surgical ligation and medical therapy both have their drawbacks, interventional catheterisation can be considered as an alternative means of closing the ductus arteriosus. Our aim was to analyse the feasibility, safety and efficacy of this device in premature infants weighing <1200 g at procedure.

METHODS

Eighteen premature infants underwent transcatheter closure. The procedure was performed in the catheterisation laboratory by venous cannulation without angiography. The position of the occluder was directed by X-ray and ultrasound. We looked at procedural details, device size selection, complications and short-term and mid-term outcomes.

RESULTS

Eighteen infants born at gestational ages ranging between 23.6 and 29+6 weeks (mean±SD 25+6±3 weeks) underwent transcatheter PDA closure. Their mean age and weight at the time of the procedure was 20 days (range 8-44 days) and 980 g (range 680-1200 g), respectively. The mean PDA and device waist diameters were 3.2±0.6 mm (range 2.2-4 mm) and 4.5±0.6 mm, respectively, and the mean PDA and device lengths were 4.3±1.2 mm (range 2-10 mm) and 2.5±0.9 mm, respectively. Complete closure was achieved in all but one patient. There was no device migration. One patient developed a left pulmonary artery obstruction. Three infants died. Two deaths were related to complications of prematurity and one to the procedure.

CONCLUSIONS

Transcatheter closure of a PDA is feasible in very low weight infants with ADOIIAS and is an alternative to surgery. Success requires perfect selection and placement of the occluder.

Surgical Ligation Versus Percutaneous Closure of Patent Ductus Arteriosus in Very Low-Weight Preterm Infants: Which are the Real Benefits of the Percutaneous Approach?

Percutaneous treatment of patent ductus arteriosus (PDA) in extreme premature infants is technically difficult, and therefore, often not consider as an alternative to surgery. The main objective of our work was to compare respiratory status prior and post ductal closure and morbi-mortality, in our series of preterm infants with percutaneous PDA closure versus surgical ligation in the same time-period. Retrospective review of all premature infants submitted to percutaneous and surgical PDA closure from January 2011 to December 2016. All the antenatal, perinatal, and postnatal characteristics were collected. The main outcome was the assessment of the pulmonary status before and after ductal closure using a pulmonary score. Secondary outcomes included moderate-severe disability in neurodevelopment, death before discharge, moderate-severe chronic lung disease, and morbidity at discharge. 25 patients with a mean weight of 1330 g (± 280) underwent percutaneous closure of PDA with ADO-II-AS, and a total of 53 underwent surgical ligation. 28/53 with similar gestational age, birth weight, and procedure weight to those in the percutaneous group, were selected to perform the comparative study. Ductal closure (percutaneous and surgical) resulted in improved respiratory status. However, percutaneous group achieved a fastest respiratory improvement, than surgical group. The surgical closure group associated higher morbidity among survivors (HIV, number of sepsis, need, and duration of inotropics post-interventionism). The incidence of recurrent laryngeal nerve palsy among the surgical group was 17%. Percutaneous closure of PDA in carefully selected low-weight preterm infants is a safe and reliable alternative to surgical ligation.

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.

Prophylactic Indomethacin Compared with Delayed Conservative Management of the Patent Ductus Arteriosus in Extremely Preterm Infants: Effects on Neonatal Outcomes

OBJECTIVE

To determine whether prophylactic indomethacin (PINDO) has more or less morbidity than delayed conservative management of the moderate-to-large patent ductus arteriosus (PDA).

STUDY DESIGN

We performed a prospective double cohort controlled study of infants delivered at ≤27^6/7 weeks gestation (n = 397). From January 2005 through April 2011, all infants were treated with PINDO (n = 247). From May 2011 through August 2016, no infant was treated with indomethacin until at least 8 postnatal days (conservative epoch, n = 150). Echocardiograms were performed on day 7 and at planned intervals until the PDA was small or closed. A single neonatologist prospectively collected all data.

RESULTS

The incidence of moderate-to-large PDA on day 7 and duration of exposure to moderate-to-large PDA were significantly less in the PINDO epoch (incidence = 10%, median = 2 days) than the conservative epoch (incidence = 67%, median = 14 days). Ligation rates were low in both epochs (PINDO = 14%, conservative = 5%). In multivariate analyses, PINDO infants had a significantly lower incidence of bronchopulmonary dysplasia (BPD) (risk ratio = 0.68, CI: 0.46-0.89) and BPD or death (risk ratio= 0.78, CI: 0.62-0.95) than conservative infants. There were no differences between the epochs in death, intraventricular hemorrhage grades 3 and 4, necrotizing enterocolitis, or retinopathy of prematurity receiving treatment. The effects of PINDO on BPD and BPD or death were no longer significant when analyses were adjusted for presence of a moderate-to-large PDA on day 7. The significant effects of PINDO were independent of whether or not a ligation was performed.

CONCLUSIONS

PINDO decreases BPD and BPD or death compared with delayed conservative PDA management. These effects are mediated by closure of the PDA.

Preoperative echocardiographic measures of left ventricular mechanics are associated with postoperative vasoactive support in preterm infants undergoing patent ductus arteriosus ligation

OBJECTIVE

Preoperative risk factors associated with poor outcomes after patent ductus arteriosus ligation in preterm infants have not been well defined. The aim of this study was to determine the association between preoperative echocardiographic measures of left ventricular mechanics and postoperative clinical outcomes after patent ductus arteriosus ligation.

METHODS

Preterm infants less than 90 days of age with no other significant congenital anomalies who underwent patent ductus arteriosus ligation between 2007 and 2015 were considered for retrospective analysis. The primary outcome was peak postoperative vasoactive inotropic score. Conventional echocardiographic measures of ventricular size, function, and patent ductus arteriosus size were performed. Echocardiographic single-beat, pressure-volume loop analysis estimates of contractility (end-systolic elastance) and afterload (arterial elastance) were calculated. Ventriculoarterial coupling was assessed using the arterial elastance/end-systolic elastance ratio. Multivariable linear regression was performed using clinical and echocardiographic data.

RESULTS

Echocardiograms from 101 patients (42.5% male) were analyzed. We found a statistically significant association between vasoactive inotropic score and both end-systolic elastance and arterial elastance. No patient with arterial elastance/end-systolic elastance greater than 0.78 (n = 32) had a vasoactive inotropic score 20 or greater. Analysis of our secondary outcomes found associations between preoperative end-systolic elastance and postoperative urine output less than 1 mL/kg/h at 24 hours, creatinine change greater than 0.5 mg/dL, and time to first extubation.

CONCLUSIONS

End-systolic elastance and arterial elastance were the only predictors of postoperative vasoactive inotropic score after patent ductus arteriosus ligation in preterm infants. Those neonates with increased contractility and low afterload were at highest risk for elevated inotropic support. These findings suggest a role for echocardiographic end-systolic elastance and arterial elastance in the preoperative assessment of preterm infants undergoing patent ductus arteriosus ligation.

Prophylactic Indomethacin Revisited

Persistent patency of the ductus arteriosus (PDA) has challenged neonatologists for more than 40 years.^, Surgical ligation of the ductus was first performed in children nearly 80 years ago and proved that prevention of prolonged exposure to left-to-right shunting through the ductus arteriosus improved pulmonary, cardiac, and systemic outcomes. In the 1970s, the discovery that nonsteroidal anti-inflammatory drugs could induce PDA closure^– and are effective in infants born preterm^, provided neonatologists with a pharmacologic alternative to surgery. The clear advantages, however, of having a medical approach have been clouded by conflicting information on the long-term benefits of treatment, disagreement regarding the clinical indicators that warrant treatment for PDA, optimal drug choice, preferred dosing regimens, and indecision regarding the best time to treat a select population of fragile preterm infants.

Trends in Patent Ductus Arteriosus Diagnosis and Management for Very Low Birth Weight Infants

OBJECTIVE

To examine yearly trends of patent ductus arteriosus (PDA) diagnosis and treatment in very low birth weight infants.

METHODS

In this retrospective cohort study of very low birth weight infants (<1500 g) between 2008 and 2014 across 134 California hospitals, we evaluated PDA diagnosis and treatment by year of birth. Infants were either inborn or transferred in within 2 days after delivery and had no congenital abnormalities. Intervention levels for treatment administered to achieve ductal closure were categorized as none, pharmacologic (indomethacin or ibuprofen), both pharmacologic intervention and surgical ligation, or ligation only. Multivariable logistic regression was used to assess risk factors for PDA diagnosis and treatment.

RESULTS

PDA was diagnosed in 42.8% (12 002/28 025) of infants, with a decrease in incidence from 49.2% of 4205 infants born in 2008 to 38.5% of 4001 infants born in 2014. Pharmacologic and/or surgical treatment was given to 30.5% of patients. Between 2008 and 2014, the annual rate of infants who received pharmacologic intervention (30.5% vs 15.7%) or both pharmacologic intervention and surgical ligation (6.9% vs 2.9%) decreased whereas infants who were not treated (60.5% vs 78.3%) or received primary ligation (2.2% vs 3.0%) increased.

CONCLUSIONS

There is an increasing trend toward not treating patients diagnosed with PDA compared with more intensive treatments: pharmacologic intervention or both pharmacologic intervention and surgical ligation. Possible directions for future study include the impact of these trends on hospital-based and long-term outcomes.

Patent Ductus Arteriosus in the Preterm Infant: Diagnostic and Treatment Options

BACKGROUND

The incidence of hemodynamically significant patent ductus arteriosus (hsPDA) increases with decreasing gestational age and is associated with many common morbidities of extreme prematurity. Controversies remain surrounding the definition of hsPDA, the population of infants requiring treatment, the appropriate timing and method of treatment, and the outcomes associated with PDA and its therapies.

PURPOSE

This integrative literature review focuses on diagnostic and treatment recommendations derived from the highest levels of evidence.

SEARCH STRATEGY

PubMed and CINAHL were searched using key words "neonatal" and "patent ductus arteriosus" to discover the highest levels of evidence surrounding diagnosis, treatment methods, and outcomes.

FINDINGS/RESULTS

The lack of consensus surrounding the diagnosis and clinical significance of PDA hinders meta-analysis across studies and confounds understanding of appropriate management strategies. Novel biomarkers, pharmaceutical choices, and transcatheter closure methods are expanding diagnostic and treatment options.

IMPLICATIONS FOR PRACTICE

Infants weighing less than 1000 g are at highest risk. Prophylactic closure is no longer recommended, although early asymptomatic therapy is still preferred by some to avoid prolonged pulmonary overcirculation or decreased renal and gut perfusion. Conservative treatment measures such as fluid restriction and diuretic administration have not consistently proven effective and are in some instances detrimental. Cyclooxygenase inhibitors are effective but have adverse renal and mesenteric effects. Oral ibuprofen is associated with lower instance of necrotizing enterocolitis.

IMPLICATIONS FOR RESEARCH

Well-defined staging criteria would aid in comparison and meta-analysis. Trials that include a control group that receives no therapy may help separate the outcomes associated with prematurity from those associated with PDA.

Patent Ductus Arteriosus Treatment in Very Preterm Infants: A European Population-Based Cohort Study (EPICE) on Variation and Outcomes

BACKGROUND

Spontaneous closure of patent ductus arteriosus (PDA) occurs frequently in very preterm infants and despite the lack of evidence for treatment benefits, treatment for PDA is common in neonatal medicine.

OBJECTIVES

The aim of this work was to study regional variations in PDA treatment in very preterm infants (≤31 weeks of gestation), its relation to differences in perinatal characteristics, and associations with bronchopulmonary dysplasia (BPD) and survival without major neonatal morbidity.

METHODS

This was a population-based cohort study in 19 regions in 11 European countries conducted during 2011 and 2012. A total of 6,896 infants with data on PDA treatment were included. The differences in infant characteristics were studied across regions using a propensity score derived from perinatal risk factors for PDA treatment. The primary outcomes were a composite of BPD or death before 36 weeks postmenstrual age, or survival without major neonatal morbidity.

RESULTS

The proportion of PDA treatment varied from 10 to 39% between regions (p < 0.001), and this difference could not be explained by differences in perinatal characteristics. The regions were categorized according to a low (<15%, n = 6), medium (15-25%, n = 9), or high (>25%, n = 4) proportion of PDA treatment. Infants treated for PDA, compared to those not treated, were at higher risk of BPD or death in all regions, with an overall propensity score adjusted risk ratio of 1.33 (95% confidence interval 1.18-1.51). Survival without major neonatal morbidity was not related to PDA treatment.

CONCLUSIONS

PDA treatment varies largely across Europe without associated variations in perinatal characteristics or neonatal outcomes. This finding calls for more uniform guidance for PDA diagnosis and treatment in very preterm infants.

Mandatory Closure Versus Nonintervention for Patent Ductus Arteriosus in Very Preterm Infants

OBJECTIVE

To determine whether a nonintervention approach for treating hemodynamically significant patent ductus arteriosus (PDA) is associated with decreased mortality and/or morbidity compared with a mandatory closure approach in extremely low birth weight infants.

STUDY DESIGN

We reviewed the medical records of 178 infants of 23-26 weeks' gestational age with PDA, requiring ventilator treatment, and with hemodynamically significant PDA ≥2 mm in size. Mandatory closure was used during period I (July 2009 to December 2011, n = 81), and nonintervention was used during period II (January 2012 to June 2014, n = 97).

RESULTS

During period I, 64% of infants were first treated with indomethacin, and 82% were ultimately ligated surgically. During period II, no infant was treated with indomethacin and/or ligation. The average postnatal day of PDA closure was day 13 and day 44 during periods I and II, respectively. There was significantly more use of diuretics and fluid restriction during period II compared with period I. There was no difference in mortality or morbidities such as necrotizing enterocolitis or intraventricular hemorrhage. The incidence of bronchopulmonary dysplasia (BPD) and the propensity score adjusted OR of BPD were significantly lower during period II compared with period I.

CONCLUSIONS

Despite longer PDA exposure, nonintervention was associated with significantly less BPD compared with mandatory closure. Additional study is warranted to determine the benefits and risks of non-intervention for the hemodynamically significant PDA in extremely low birth weight infants.