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

Trial of Selective Early Treatment of Patent Ductus Arteriosus with Ibuprofen

BACKGROUND

The cyclooxygenase inhibitor ibuprofen may be used to treat patent ductus arteriosus (PDA) in preterm infants. Whether selective early treatment of large PDAs with ibuprofen would improve short-term outcomes is not known.

METHODS

We conducted a multicenter, randomized, double-blind, placebo-controlled trial evaluating early treatment (≤72 hours after birth) with ibuprofen for a large PDA (diameter of ≥1.5 mm with pulsatile flow) in extremely preterm infants (born between 23 weeks 0 days' and 28 weeks 6 days' gestation). The primary outcome was a composite of death or moderate or severe bronchopulmonary dysplasia evaluated at 36 weeks of postmenstrual age.

RESULTS

A total of 326 infants were assigned to receive ibuprofen and 327 to receive placebo; 324 and 322, respectively, had data available for outcome analyses. A primary-outcome event occurred in 220 of 318 infants (69.2%) in the ibuprofen group and 202 of 318 infants (63.5%) in the placebo group (adjusted risk ratio, 1.09; 95% confidence interval [CI], 0.98 to 1.20; P = 0.10). A total of 44 of 323 infants (13.6%) in the ibuprofen group and 33 of 321 infants (10.3%) in the placebo group died (adjusted risk ratio, 1.32; 95% CI, 0.92 to 1.90). Among the infants who survived to 36 weeks of postmenstrual age, moderate or severe bronchopulmonary dysplasia occurred in 176 of 274 (64.2%) in the ibuprofen group and 169 of 285 (59.3%) in the placebo group (adjusted risk ratio, 1.09; 95% CI, 0.96 to 1.23). Two unforeseeable serious adverse events occurred that were possibly related to ibuprofen.

CONCLUSIONS

The risk of death or moderate or severe bronchopulmonary dysplasia at 36 weeks of postmenstrual age was not significantly lower among infants who received early treatment with ibuprofen than among those who received placebo. (Funded by the National Institute for Health Research Health Technology Assessment Programme; Baby-OSCAR ISRCTN Registry number, ISRCTN84264977.).

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).

Personalized Evidence-Based Management of Patent Ductus Arteriosus in Preterm Infants

There is no universal consensus on management of patent ductus arteriosus (PDA) in preterm infants and it varies significantly worldwide, even among the clinicians within units. The decision to treat requires a thorough understanding of the clinical status of the patient, clinical evaluation of PDA, echocardiographic diagnosis, and hemodynamic impact of ductal shunt on the pulmonary and systemic circulation. In this article, updated evidence on the efficacy and adverse effects of pharmacological treatment options and expectant management are presented, while highlighting the long-term benefits of PDA treatment remains equivocal and controversial. The authors propose a schematic targeted PDA treatment approach based on gestational and chronological age for practical clinical use, and they emphasize important future directions including advancement in PDA device closure techniques, diagnostic echo-parameters, hemodynamic evaluation to assess the impact on other organs, and understanding the long-term outcomes.

Increasing the dose of ibuprofen with postnatal age to close a hemodynamically significant patent ductus arteriosus in very preterm infants

Patent ductus arteriosus (PDA) is associated with neonatal morbidities in high-risk preterm infants. Early neonatal treatment by ibuprofen induces the ductus arteriosus (DA) closure in approximatively 60% of infants. Dose escalation of ibuprofen according to postnatal age has been suggested for improving the DA closure rate. The aim of this study was to assess the efficacy and tolerance of an increasing dose regimen of ibuprofen. This single-center retrospective cohort study involved infants hospitalized from 2014 to 2019 in our neonatal unit. Selection criteria were gestational age < 30 weeks, birth weight < 1000 g, and treatment by ibuprofen. Three dose levels were used and consisted of a daily intravenous injection of ibuprofen-tris-hydroxymethyl-aminomethane (ibuprofen-THAM) for three consecutive days: (i) 10 -5 -5 mg/kg before the 70th h of life (H70) (dose level 1), (ii) 14 -7 -7 mg/kg between H70 and H108 (dose level 2), (iii) 18 -9 -9 mg/kg after H108 (dose level 3). The ibuprofen-induced DA closure was compared between ibuprofen schedules, and the Cox proportional-hazard regression was performed to identify factors associated with the ibuprofen efficacy. Tolerance was assessed through renal function, acidosis, and platelet count. One hundred forty-three infants met the inclusion criteria. The ibuprofen-induced DA closure was observed in 67 infants (46.8%). One course of ibuprofen at dose level 1 was more efficient in closing the DA than other schedules (dose level 1, one course (n = 70): 71%, dose level 2 or 3, one course (n = 20): 45%, two-course schedules (n = 53): 15%, p < 0.0001). Independent factors associated with ibuprofen-induced DA closure were a complete antenatal schedule of steroids (p = 0.001), a lower CRIB II score (p = 0.009), and a lower and earlier exposure to ibuprofen (p < 0.0001 and p = 0.002). No severe side effects were observed. Neonatal mortality and morbidities were similar regardless of the infant's response to ibuprofen.  Conclusion: Increasing ibuprofen doses with postnatal age failed to reach an efficacy similar to earlier treatment. Although the infant response to ibuprofen was likely to depend on multiple factors, the optimal use of ibuprofen included its early initiation. What is Known: • Ibuprofen is the current first-line treatment for patent ductus arteriosus during the early neonatal period in very preterm infants. • However, the ibuprofen efficacy rapidly declined with postnatal age during the first week of life. A dose escalation of ibuprofen according to postnatal age has been suggested to improve the ibuprofen-induced ductus arteriosus closure. What is New: • The rapid drop of ibuprofen's ability to close hemodynamically significant patent ductus arteriosus persisted beyond the postnatal day 2 despite the dose adjustment arguing for an early initiation to optimize its efficacy. • The early selection of patients who will suffer from patent ductus arteriosus-related morbidities and who will positively respond to ibuprofen is an issue that could determine the future place of ibuprofen in the patent ductus arteriosus management.

A Global Perspective on PDA Management in the Extremely Premature: Shifting Trend Toward Transcatheter Closure

Patent ductus arteriosus (PDA) is a frequently encountered defect in infants born extremely premature (≤26 weeks' gestation). Historically, closure of the PDA was performed using cyclooxygenase inhibitor medications or by surgical ligations. However, the benefits of PDA closure using these therapies have never been demonstrated, albeit studies have previously not focused on the extremely premature infants. Therefore, there was a worldwide trend toward conservative management of the PDA. With improved survival of extremely premature infants, comorbidities associated with the PDA has increased, resulting in finding alternate treatments such as transcatheter patent ductus arteriosus closure (TCPC) for this population. Currently, there is a renewed interest toward selective treatment of the PDA in this high-risk cohort of small infants. This Comprehensive Review article inspects the globally changing trends in the management of the PDA in premature infants, with a special focus on the rising adoption of TCPC. Moreover, this article compiles data from several neonatal networks worldwide to help understand the problem at hand. Understanding the current management of premature infants and their outcomes is fundamentally essential if pediatric cardiologists are to offer TCPC as a viable therapeutic option for this population. This article aims to serve as a guide for pediatric cardiologists on this topic by compiling the results on landmark clinical trials on PDA management and the controversies that arise from these trials. Comparative outcomes from several countries are presented, including interpretations and opinions of the data from experts globally. This is a step toward coming to a global consensus in PDA management in premature infants.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Management of patent ductus arteriosus in very preterm infants in England and Wales: a retrospective cohort study

OBJECTIVE

To describe the diagnosis and treatment of patent ductus arteriosus (PDA) in infants born at <32 weeks' gestational age (GA) in England and Wales between 2010 and 2017.

STUDY DESIGN

Retrospective cohort study using routinely recorded data from the National Neonatal Research Database of infants born at <32 weeks admitted to neonatal units in England and Wales from 2010 to 2017.

RESULTS

Among 58 108 infants born at <32 weeks' GA, 28.3% (n=16 440) had a PDA diagnosed clinically or with echocardiographic confirmation. Of these, 34.8% (n=5721; 9.8% of total <32 weeks' infants included) had PDA treatment including 7.6% (n=1255) with indomethacin, 23.5% (n=3857) with ibuprofen and 5.6% (n=916) with surgical closure. The highest incidence of PDA was among infants born at 24 and 25 weeks' GA (70.2% and 70.8%, respectively), decreasing to 6.1% among infants born at 31 weeks' GA. The percentage of infants with a PDA increased over the study period (25.5% in 2010 to 28.5% in 2017). The percentage of infants who received ibuprofen or indomethacin or had PDA surgery decreased from 41.3% in 2010 to 33.7% in 2017, with an increase in use of ibuprofen from 20.2% to 27.3% while use of indomethacin decreased from 20.0% to 8.8%. Surgical closure of PDA decreased from 9.1% to 3.0%. Indomethacin was used for median (IQR) 3 (2-5) days while ibuprofen was given for 3 (2-4) days, at a median of 8 and 10 days after birth, respectively; surgical treatment was used later at 33 (24-45) days after birth.

CONCLUSIONS

Ibuprofen is the preferred drug and surgical interventions are becoming less frequent for PDA closure among very preterm infants in England and Wales.

TRIAL REGISTRATION NUMBER

NCT03773289.

Outcomes for Infants Born in Perinatal Centers Performing Fewer Surgical Ligations for Patent Ductus Arteriosus: A Swiss Population-Based Study

OBJECTIVE

To assess patent ductus arteriosus treatment variation between Swiss perinatal centers and to determine its effect on outcome in a population-based setting.

STUDY DESIGN

This was a retrospective cohort study of infants born less than 28 weeks of gestation between 2012 and 2017. Outcomes between surgically ligated and pharmacologically treated infants as well as infants born in centers performing ≤10% ligation ("low" group) and >10% ("high" group) were compared using logistic regression and 1:1 propensity score matching. Matching was based on case-mix and preligation confounders: intraventricular hemorrhages grades 3-4, necrotizing enterocolitis, sepsis, and ≥28 days' oxygen supply.

RESULTS

Of 1389 infants, 722 (52%) had pharmacologic treatment and 156 (11.2%) received surgical ligation. Compared with infants who received pharmacologic treatment, ligated infants had greater odds for major morbidities (OR 2.09, 95% CI 1.44-3.04) and 2-year neurodevelopmental impairment (OR 1.81, 95% CI 1.15-2.84). Mortality was comparable after restricting the cohort to infants surviving at least until day 10 to avoid survival bias. In the "low" group, 34 (4.9%) of 696 infants were ligated compared with 122 (17.6%) of 693 infants in the "high" group. Infants in the "high" group had greater odds for major morbidities (OR 1.49, 95% CI 1.11-2.0).

CONCLUSIONS

Our analysis identified a burden on infants receiving surgical ligation vs pharmacologic treatment in a population-based setting where there was no agreed-on common procedure. These results may guide a revision of patent ductus arteriosus treatment practice in Switzerland.

Ductus diameter and left pulmonary artery end-diastolic velocity at 3 days of age predict the future need for surgical closure of patent ductus arteriosus in preterm infants: A post-hoc analysis of a prospective multicenter study

BACKGROUND

There is inconsistent evidence suggesting the clinical relevance of the early detection of future needs of preterm patent ductus arteriosus (PDA) surgery. We tested the hypothesis that echocardiographic indices at 3 days of age predict the future need for PDA surgery.

METHODS

We analyzed a database including the clinical and echocardiographic data of 710 preterm infants with gestational ages between 23 and 29 weeks in 34 Japanese neonatal intensive care units, and prospectively collected data over 14 months. The predictive or discriminative ability of each echocardiographic index at 3 days of age for future PDA surgical closure was evaluated using multivariable logistic regression analyses with adjustment for gestational age, sex, and small-for-gestational-age status, according to the areas under the receiver-operating characteristic curves (AUCs) of the models.

RESULTS

A total of 688 eligible patients (median gestational age: 26 weeks, body weight at birth: 843 g) were analyzed, of whom 77 (11%) underwent PDA surgery (median age: 21 days) after full consideration of clinical conditions. The AUC of PDA diameter (PDAd) was the largest, followed by that of the left pulmonary artery end-diastolic velocity (LPAedv). Compared with the ratio of left atrial-to-aorta diameter (AUC 0.76), PDAd (AUC 0.84, p < 0.001) and LPAedv (AUC 0.82, p = 0.003) were significantly better predictors of future PDA surgery.

CONCLUSION

Echocardiographic indices at 3 days of age, especially PDAd and LPAedv, may predict the future need for surgical closure of PDA in preterm infants.

Weight gain in the first week of life and its association with morbidity and mortality in extremely low birthweight (ELBW) infants

BACKGROUND

Weight gain in the first week of life is indicative of fluid excess in preterm neonates.

AIMS

To determine if morbidity and/or mortality of extremely low birthweight (ELBW) infants was lower in those who did not have excess weight gain in the first week of life, compared with those who did.

STUDY DESIGN

Retrospective cohort study.

SUBJECTS

ELBW infants born from 1st May 2014 - 31st May 2019.

EXCLUSIONS

major congenital abnormalities (including hydrops), died within the first 7 days, no recorded weight on day 6, 7 or 8.

OUTCOME MEASURES

We compared infants whose weight was greater than birthweight by day 7 and infants whose weight remained at, or below, birthweight by day 7.

RESULTS

There were 312 ELBW infants in the study population: 15 (5%) died before discharge from hospital. Holding birthweight and gestational age (GA) constant, the odds of death in neonates with day 7 weight >birthweight was about 3 times the odds of death in neonates with day 7 weight ≤birthweight (adjusted odds ratio 3.18, 95% confidence interval 0.66-15.26, p = 0.15). Neonates with day 7 weight >birthweight were more likely to have had a PDA that required treatment than those with day 7 weight ≤birthweight (65% versus 43% respectively; p <0.001).

CONCLUSIONS

ELBW infants who gain weight in the first week of postnatal life, have a greater risk of PDA requiring treatment and may have a higher risk of mortality than infants who lose weight in the first week of life.

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.

Protective factors against preterm infants to develop significant patent ductus arteriosus

BACKGROUND

Identifying preterm infants with a higher likelihood of spontaneous patent ductus arteriosus (PDA) closure would be desirable. This study aimed to examine daily PDA status during the first week of life for very low birthweight (VLBW, <1500 g) preterm infants and to develop a scoring system to predict spontaneous PDA closure.

METHODS

We enrolled VLBW infants admitted between January 2016 and January 2017 and performed daily echocardiographic screening for PDA existence. Oxygen index (OI, mean airway pressure × fraction of inspired oxygen/partial pressure of arterial oxygen) was applied to represent the respiratory condition.

RESULTS

A total of 215 VLBW infants were enrolled, and the accumulative incidence of spontaneous PDA closure by age 1 week was 80%, 70%, and 34% for infants born of gestational age (GA) ≥30, 28-29, and ≤27 weeks, respectively. Of these 215 infants, 184 infants entered the second phase to establish the scoring system. Infants with spontaneous PDA closure were more mature (GA 29.2 ± 2.3 vs. 26.9 ± 2.3 weeks, p < 0.001), had lower OI (2.8 ± 2.2 vs. 5.6 ± 5.3, p < 0.001) and were less likely to need endotracheal intubation (23% vs. 68%, p < 0.001). Using the receiver operating characteristics curve, OI <2.5 was determined favoring higher PDA closure incidence. The score was calculated based on the odds ratio generated in multiple regression: 4, 3 and 1 points for GA ≥30, 28-29 and ≤27 weeks, 2 and 1 points for OI <2.5 and ≥2.5, and 3 and 1 points for without and with endotracheal intubation. Using score ≥6 to predict PDA closure, the sensitivity and specificity were 0.77 and 0.72.

CONCLUSION

A score made up of GA, OI and need for intubation was proposed to predict spontaneous PDA closure by age 1 week, which could be helpful to clinicians in the management of PDA in preterm infants.

Hemodynamic support of the micropreemie: Should hydrocortisone never be left out?

Hemodynamic support for a micropreemie is critically important for preventing mortality and morbidity. An essential consideration in hemodynamic support is insufficient transition from fetal to neonatal circulation and inadequate cortisol production. The first 72 h of life are the most critical, especially when myocardial function is immature and impaired. Therefore, there is a need to determine and adjust preload, myocardial contractility, and afterload appropriately using repeated functional echocardiography. In addition, if myocardial function is not responsive to these attempts at hemodynamic management, hydrocortisone must be used to minimize the suboptimal perfusion burden. Fetal cortisol production is supported by a supply of progesterone from the placenta, and postnatally, adrenal cortisol production in the extremely preterm infant may be inadequate if the infant is placed under excessive stress. This leads to relative adrenal insufficiency which may last for up to several weeks after birth and lead to late-onset circulatory collapse, necessitating treatment with physiological doses of hydrocortisone.

Variations in Neonatal Length of Stay of Babies Born Extremely Preterm: An International Comparison Between iNeo Networks

OBJECTIVE

To compare length of stay (LOS) in neonatal care for babies born extremely preterm admitted to networks participating in the International Network for Evaluating Outcomes of Neonates (iNeo).

STUDY DESIGN

Data were extracted for babies admitted from 2014 to 2016 and born at 24 to 28 weeks of gestational age (n = 28 204). Median LOS was calculated for each network for babies who survived and those who died while in neonatal care. A linear regression model was used to investigate differences in LOS between networks after adjusting for gestational age, birth weight z score, sex, and multiplicity. A sensitivity analysis was conducted for babies who were discharged home directly.

RESULTS

Observed median LOS for babies who survived was longest in Japan (107 days); this result persisted after adjustment (20.7 days more than reference, 95% CI 19.3-22.1). Finland had the shortest adjusted LOS (-4.8 days less than reference, 95% CI -7.3 to -2.3). For each week's increase in gestational age at birth, LOS decreased by 12.1 days (95% CI -12.3 to -11.9). Multiplicity and male sex predicted mean increases in LOS of 2.6 (95% CI 2.0-3.2) and 2.1 (95% CI 1.6-2.6) days, respectively.

CONCLUSIONS

We identified between-network differences in LOS of up to 3 weeks for babies born extremely preterm. Some of these may be partly explained by differences in mortality, but unexplained variations also may be related to differences in clinical care practices and healthcare systems between countries.

Size of Patent Ductus Arteriosus and Echocardiographic Markers of Shunt Volume in Preterm Infants Based on Postnatal Age

Objective: This study was conducted in order to compare the strength of correlation between echocardiographic markers of shunt volume and patent ductus arteriosus (PDA) diameter based on postnatal age. Methods: This retrospective study focused on preterm infants (aged <32 weeks of gestation) admitted to the Neonatal Intensive Care Unit of Korea University Ansan Hospital, between April 2014 and December 2017, who studied serial targeted neonatal echocardiography (TNE) for PDA during hospitalization. The association between echocardiographic characteristics and duct size was divided into the following days: within 3 days (very early, VE), 4-7 days after birth (early, E), and after 8 days of birth (late, L). Results: We found 113 assessments conducted on 57 infants in the VE period, 92 assessments on 40 infants in the E period, and 342 assessments on 37 infants in the L period. Median gestational age and birth weight were 28⁺² weeks of gestation and 1,115 g, respectively. In the univariate regression analysis, we found a statistically significant correlation between PDA diameter and all TNE markers in the E and L days, but not in the VE period. Only ductal velocity [coefficient of determination (R ²) = 0.224], antegrade left pulmonary artery diastolic flow velocity (R ² = 0.165), left ventricular output (LVO)/superior vena cava (SVC) flow ratio (R ² = 0.048), and E/A wave ratio (R ² = 0.092) showed weak correlations with PDA diameter in the VE period. The slopes of the regressions showed significant changes based on postnatal age in the maximum ductal velocity, left atrium/aorta ratio, LVO/SVC flow ratio, and LVO. Conclusions: It is difficult to predict the echocardiographic markers of shunt volume based on the PDA diameter in preterm infants younger than 4 days. A better understanding of the changes in the hemodynamic consequences of PDA based on postnatal age is needed when considering treatment.