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

Outcomes of Patent Ductus Arteriosus Closure by Availability of Cardiac Surgeons for Infants Born Preterm

OBJECTIVE

To evaluate the treatment strategies for closure of patent ductus arteriosus (PDA) and clinical outcomes among very preterm infants based upon the availability of cardiac surgeons in neonatal intensive care units (NICUs).

STUDY DESIGN

This study retrospectively assessed infants born at 23-29 weeks of gestation who participated in a prior prospective cohort study in Japan. The primary outcome was PDA surgery. The secondary outcomes included mortality and various morbidities, such as intraventricular hemorrhage and chronic lung disease (CLD). Outcomes were compared between with-surgeon and no-surgeon NICUs using generalized linear mixed effect models, adjusted for gestational age, antenatal corticosteroid, small-for-gestational age, and unit patient volume.

RESULTS

This study included 613 infants from 27 NICUs, including 245 from 9 no-surgeon NICUs and 368 from 18 with-surgeon NICUs. Infants received significantly more prophylactic indomethacin in the no-surgeon NICUs than those in the with-surgeon NICUs. The frequency of PDA surgery showed no significant difference between the groups (9.0% vs 12%, adjusted odds ratio [aOR]: 0.56 [95% confidence interval: 0.21-1.51]). CLD was significantly more frequent in no-surgeon NICUs than in with-surgeon NICUs (55% vs 40%, aOR: 3.24 [95% CI 1.45-7.29]).

CONCLUSIONS

The frequency of PDA surgery did not differ significantly according to the availability of surgeons. The incidence of CLD was higher in no-surgeon NICUs; however, the risk of unmeasured confounding cannot be excluded due to the observational study design.

Acetaminophen for Patent Ductus Arteriosus and Risk of Mortality and Pulmonary Morbidity

OBJECTIVE

Emerging data indicate that acetaminophen may adversely affect lung health. We examined whether acetaminophen compared with cyclooxygenase (COX) inhibitor alone for patent ductus arteriosus (PDA) is associated with mortality or respiratory morbidity in extremely preterm infants.

METHODS

This is a retrospective cohort study using data from the National Institute of Child Health and Human Development Neonatal Research Network. Infants were born at 22 to 28 weeks' gestation or weighing 401 to 1000 g between 2016 and 2020 and received acetaminophen, ibuprofen, and/or indomethacin for PDA closure. The primary outcome was death or grade 2 to 3 bronchopulmonary dysplasia (BPD) at 36 weeks' postmenstrual age. Secondary outcomes included predischarge mortality and respiratory morbidities. Risk ratios were adjusted for baseline and early postnatal factors. Additional exploratory analyses were adjusted for later postnatal covariates.

RESULTS

Of 1921 infants, 627 (32.6%) received acetaminophen and 1294 (67.3%) received COX inhibitor only. Multidrug therapy (42.9% vs 4.7%) and surgical or catheter PDA closure (26.5% vs 19.9%) were more common among acetaminophen-exposed infants. Death or grade 2 to 3 BPD at 36 weeks' postmenstrual age was similar between infants treated with acetaminophen versus COX inhibitor only (57.1% vs 58.3%; adjusted relative risk [aRR] 0.96, 95% confidence interval [CI] 0.87-1.06). Acetaminophen was associated with increased risk of predischarge mortality (13.3% vs 10.0%) when adjusting for perinatal and early postnatal factors (aRR 1.42, 95% CI 1.02-1.93), but not in exploratory analyses that included later postnatal factors (aRR 1.28, 95% CI 0.91-1.82).

CONCLUSIONS

Treatment with acetaminophen versus COX inhibitor alone for PDA was not associated with the composite outcome of death or BPD in extremely preterm infants. Our results support further evaluation of whether acetaminophen for PDA increases mortality.

Proactive Diagnosis and Tailor-Made Treatment of Patent Ductus Arteriosus in Very Preterm Infants with Routine Echocardiography in Japan: A post hoc Analysis of the PLASE Study

INTRODUCTION

A feature of the management of extremely preterm infants in Japan is proactive circulatory management using early routine echocardiography performed by neonatologists.

METHODS

This study was a post hoc analysis of the Patent ductus arteriosus and Left Atrial Size Evaluation in preterm infants (PLASE) study, which is a prospective cohort study including preterm infants admitted to 34 tertiary neonatal intensive care units in Japan between October 2015 and December 2016. We described the details of the treatment strategy of patent ductus arteriosus (PDA) based on early routine echocardiography.

RESULTS

In total, 613 preterm infants were included into the analysis. Twenty percent of infants with prophylactic indomethacin were switched to therapeutic cyclooxygenase inhibitor (COX-I) before the completion of the full prophylactic indomethacin course. Therapeutic COX-I was mostly administered based on echocardiographic findings before PDA became symptomatic or hemodynamically significant. Therapeutic COX-I was frequently discontinued after one or two doses before the full course (three doses) was completed. The proportion of infants requiring additional treatment (additional therapeutic COX-I course or surgical PDA closure) after discontinued COX-I courses (<3 doses) compared to infants after completed 3 doses course was significantly lower (after the first therapeutic COX-I course 46% vs. 68%, p < 0.001) or without a significant difference (after the second or third course).

CONCLUSIONS

The clinical management of PDA in Japan featured (1) COX-I administration based on echocardiographic findings before symptomatic or hemodynamically significant PDA appeared and (2) frequent discontinuation of therapeutic COX-I before completing the standard three doses course.

Treatment of patent ductus arteriosus and short-term outcomes among extremely preterm infants: a multicentre cohort study

Background

The optimal treatment strategy for patent ductus arteriosus (PDA) in extremely preterm infants is currently highly controversial. This study aimed to evaluate the association between PDA treatment and short-term outcomes among extremely preterm infants.

Methods

This cohort study included all extremely preterm infants (≤27 and 6/7 weeks) who were admitted to hospitals participating in the Chinese Neonatal Network from January 2019 to December 2021, and were diagnosed to have PDA by echocardiogram. PDA treatment was defined as medical treatment and/or surgical ligation of PDA during hospitalization. Short-term outcomes included death, bronchopulmonary dysplasia (BPD), death/BPD, retinopathy of prematurity, necrotizing enterocolitis, and severe brain injury. Multivariate logistic regression was used to evaluate the association between PDA treatment and outcomes. Subgroup analysis were performed among infants with different respiratory support on 3 and 7 days of life.

Findings

A total of 2494 extremely preterm infants with the diagnosis of PDA were enrolled, of which 1299 (52.1%) received PDA treatment. PDA treatment was significantly associated with lower risk of death (adjusted odds ratio, 0.48; 95% confidence interval, 0.38-0.60). The decreased risk of death was accompanied by increased risk of BPD and death/BPD. In subgroup analysis according to respiratory support, PDA treatment was associated with lower risk of death among infants who required invasive ventilation. However, the beneficial effect on death was not significant among infants who did not require invasive ventilation.

Interpretation

PDA treatment was associated with reduced mortality in extremely preterm infants, but this beneficial effect was mainly present among infants who required invasive ventilation.

Funding

This study was funded by the Shanghai Science and Technology Commission's Scientific and Technological Innovation Action Plan (21Y21900800) and the Canadian Institutes of Health Research (CTP87518).

Association of patent ductus arteriosus with fetal factors and endotypes of prematurity

During fetal life, the ductus arteriosus (DA) acquires the mechanisms for its postnatal closure following a thorough developmental program. This program can be interrupted by preterm birth and is also susceptible to alteration during fetal life by numerous physiological and pathological stimuli. In this review, we aim to summarize the evidence on how physiological and pathological factors affect DA development, eventually leading to patent DA (PDA). Specifically, we reviewed the associations of sex, race, and pathophysiological pathways leading to very preterm birth (endotypes) with PDA incidence and pharmacological closure. Summary of evidence suggests that there are no male-female differences in the incidence of PDA among very preterm infants. In contrast, risk of developing PDA appears to be higher in infants exposed to chorioamnionitis or who are small for gestational age. Finally, hypertensive disorders of pregnancy may be associated with a better response to pharmacological treatment of PDA. All of this evidence comes from observational studies and therefore associations do not imply causation. The current trend for many neonatologists is to wait for the natural evolution of preterm PDA. Continued research is needed to identify which fetal and perinatal factors modulate the eventual late closure of PDA in very and extremely preterm infants.

Hospital variation in neonatal echocardiography among very preterm infants at US children's hospitals

OBJECTIVE

Estimate hospital variation in echocardiography (echo) among very preterm infants.

STUDY DESIGN

Retrospective cohort study of very preterm (<32 weeks) infants discharged between 2012 and 2019 from US children's hospitals. Echo exposure was identified using daily billing, and hospital variation was estimated after adjustment for illness severity. Variation in very early echo use (<3 days of life) was compared to exposure to treatment of a patent ductus arteriosus (PDA), and other practice patterns.

RESULTS

27,498 subjects across 39 children's hospitals were included. Very early echo use had the greatest hospital variation (3-34%). Increasing very early echo use was not associated with PDA treatment (p = 0.93), but was associated with nitric oxide (p < 0.01) and vasoactive medications (p < 0.01).

CONCLUSIONS

Hospital variation in echo use among preterm infants was greatest in the first few days of life and was associated with increasing nitric oxide and vasoactive medication use. The impact of this variation on clinical outcomes is uncertain and warrants further investigation.

Clinical outcomes of different patent ductus arteriosus treatment in preterm infants born between 28 and 32 weeks in Taiwan

BACKGROUND

The patent ductus arteriosus (PDA) treatment in very preterm infants is controversial. This study focused on preterm infants born at 28-32 weeks of gestation and analyzed the association between various PDA treatments and clinical outcomes.

METHODS

We conducted a retrospective cohort study of infants born at 28-32 weeks of gestation between 2016 and 2019 at 22 hospitals in the Taiwan Premature Infant Follow-up Network. We categorized the infants into four groups according to treatment strategies: medication, primary surgery, medication plus surgery, or conservative treatment.

RESULTS

A total of 1244 infants presented with PDA, and 761 (61.1%) were treated. Medication was the predominant treatment (50.0%), followed by conservative treatment (38.9%), medication plus surgery (7.6%), and primary surgery (3.5%). The risk of mortality was not reduced in the active treatment group compared to the conservative treatment group. There was a higher prevalence of severe intraventricular hemorrhage, necrotizing enterocolitis (NEC), and any degree of bronchopulmonary dysplasia (BPD) in both the primary surgery and medication plus surgery groups than in the conservative treatment group. After adjustment, both the primary surgery and medication plus surgery groups still had higher odds ratios for the occurrence of NEC and any degree of BPD.

CONCLUSIONS

Compared with active PDA treatment, conservative treatment for PDA did not increase the risk of mortality and morbidity in very preterm infants born at 28-32 weeks of gestation. The risks and benefits of surgery (PDA ligation) in these infants must be considered cautiously.