Cerebral hemodynamic change and intraventricular hemorrhage in very low birth weight infants with patent ductus arteriosus

A Comparison of Perinatal Circulatory Transition in Critical Right and Left Heart Obstructive Lesions

BACKGROUND

During perinatal transition in hypoplastic left heart syndrome (HLHS), reduced systemic blood flow (Qs) and cerebral blood flow and increased pulmonary blood flow (Qp) are observed, contributing to hemodynamic instability. The aim of the present study was to explore whether similar or discordant perinatal changes occur in critical pulmonary outflow tract obstruction (POFO) compared with HLHS and healthy control subjects.

METHODS

Echocardiography was prospectively performed at 36 to 39 gestational weeks and then serially from 6 to 96 hours after birth, before cardiac intervention. Combined cardiac output (CCO), superior vena cava (SVC) flow rate, Qs and Qp, and resistance indices (RIs) in the middle cerebral artery (MCA), celiac artery, and superior mesenteric artery were compared among the three groups.

RESULTS

In fetal POFO (n = 19) and HLHS (n = 31), CCO was comparable with that in control subjects (n = 21) because of elevated stroke volume, but CCO in POFO was lower compared with HLHS (P < .01). Compared with control subjects, POFO CCO was lower at 6 hours after delivery but comparable at 24 to 96 hours. In contrast, from 6 to 96 hours, the HLHS group had higher CCO than POFO and control subjects. Compared with control subjects, both neonates with POFO and those with HLHS had lower Qs and SVC flow (POFO at 24 hours, P < .001; HLHS 6-hour Qs and 6- to 24-hour SVC flow). Compared with control subjects, Qp was increased in POFO at 48 to 96 hours (P < .05) and in HLHS at all time points (P < .001). Compared with fetal MCA RI, postnatal MCA RI was acutely higher in both POFO and HLHS, whereas in control subjects, it tended to decrease postnatally. Celiac artery RI and superior mesenteric artery pulsatility index were higher in POFO and HLHS from 6 to 48 hours vs control subjects.

CONCLUSIONS

POFO and HLHS demonstrate divergent acute hemodynamic changes in the early neonatal period, with early decreased CCO in POFO and increased CCO in HLHS. Both demonstrate early compromise in Qs and SVC (cerebral flow) and ongoing altered splanchnic flow.

Combined (dual) drug therapy for the treatment of patent ductus arteriosus: last approach prior to ligation

OBJECTIVE

We aimed to evaluate the efficacy of combined (ibuprofen+paracetamol) medical therapy in cases of persistent haemodynamically significant patent ductus arteriosus that are resistant to standard medical monotherapy (ibuprofen and/or paracetamol) in this retrospective multi-centre study.

METHODS

The combined therapy included the administration of 15mg/kg/dose of paracetamol every 6 h for 3 days and ibuprofen at an initial dose of 10mg/kg/dose followed by 5 mg/kg/dose every 24 h. After 2 days following the administration of the last dose, the researchers evaluated the efficacy of combined treatment by conducting an echocardiographic examination.

RESULTS

Of all 42 patients who received combined therapy, 37 (88.1%) patients exhibited closure of the haemodynamically significant patent ductus arteriosus without requiring surgical ligation. Patients who did not respond to combined therapy had a higher mean birth weight and gestational age compared to those who responded (p < 0.05).

CONCLUSION

The researchers believe the success of ibuprofen and paracetamol in haemodynamically significant patent ductus arteriosus treatment may be due to their synergistic efficacy and inhibition of the prostaglandin synthesis pathway through different enzymes. The results of our retrospective trial suggest that combination therapy with paracetamol and ibuprofen can be attempted when monotherapy is unsuccessful in treating haemodynamically significant patent ductus arteriosus, especially in centres without a surgical department.

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.

Relationship of cerebral blood volume with arterial and venous flow velocities in extremely low-birth-weight infants

Unstable cerebral blood flow is theorised to contribute to the occurrence of intraventricular haemorrhage (IVH) in extremely low-birth-weight infants (ELBWIs), which can be caused by increased arterial flow, increased venous pressure, and impaired autoregulation of brain vasculature. As a preliminary step to investigate such instability, we aimed to check for correlations of cerebral blood volume (CBV), as measured using near-infrared spectroscopy, with the flow velocities of the anterior cerebral artery (ACA) and internal cerebral vein (ICV), as measured using Doppler ultrasonography. Data were retrospectively analysed from 30 ELBWIs uncomplicated by symptomatic patent ductus arteriosus, which can influence ACA velocity, and severe IVH (grade ≥ 3), which can influence ICV velocity and CBV. The correlation between tissue oxygen saturation (StO₂₎ and mean blood pressure was also analysed as an index of autoregulation. CBV was not associated with ACA velocity; however, it was significantly correlated with ICV velocity (Pearson R = 0.59 [95% confidence interval: 0.29-0.78], P = 0.00061). No correlation between StO₂ and mean blood pressure was observed, implying that autoregulation was not impaired.    Conclusion: Although our findings are based on the premise that cerebral autoregulation was unimpaired in the ELBWIs without complications, the same result cannot be directly applied to severe IVH cases. However, our results may aid future research on IVH prediction by investigating the changes in CBV when severe IVH occurs during ICV velocity fluctuation. What is Known: • The pathogenesis of IVH includes unstable cerebral blood flow affected by increased arterial flow, increased venous pressure, and impaired cerebral autoregulation. • The approaches that can predict IVH are under discussion. What is New: • ACA velocity is not associated with CBV, but ICV velocity is significantly correlated with CBV. • CBV measured using NIRS may be useful in future research on IVH prediction.

Ductus arteriosus and the preterm brain

As the approach to the patent ductus arteriosus (PDA) in the preterm infant remains controversial, the potential consequences of a significant ductal shunt on the brain should be evaluated. In this population at high risk of adverse outcomes, including intraventricular haemorrhage and white matter injury, as well as longer-term neurodevelopmental impairment, it is challenging to attribute sequelae to the PDA. Moreover, individual patient characteristics including gestational age and timing of PDA intervention factor into risks of brain injury. Haemodynamic assessment of the ductus combined with bedside neuromonitoring techniques improve our understanding of the role of the PDA in neurological injury. Effects of various PDA management strategies on the brain can similarly be investigated. This review incorporates current understanding of how the PDA impacts the developing brain of preterm infants and examines modalities to measure these effects.

Combination pharmacotherapy for patent ductus arteriosus: Rationale and evidence

While cyclooxygenase inhibitors have been the most common medications used to facilitate earlier closure of patent ductus arteriosus in preterm infants, adverse effects and low efficacy in extremely low gestational age neonates (ELGANs) have highlighted a need for alternative options. Combination therapy with acetaminophen and ibuprofen is a novel strategy for PDA treatment in ELGANs, as it may facilitate higher ductal closure rates via additive action on two separate pathways inhibiting prostaglandin production. Initial small observational studies and pilot randomized clinical trials indicate potentially higher efficacy of the combination regime to induce ductal closure in comparison to treatment with ibuprofen alone. In this review, we examine the potential clinical impact of treatment failure in ELGANs with significant PDA, highlight the biological rationale in support of studying combination therapy, and review the randomized and non-randomized studies to date. With the rising number of ELGANs receiving neonatal intensive care, who are vulnerable to PDA-related morbidities, there is an urgent need for adequately powered clinical trials to systematically investigate the efficacy and safety of combination therapy for PDA treatment.

Sex Differences in Patent Ductus Arteriosus Incidence and Response to Pharmacological Treatment in Preterm Infants: A Systematic Review, Meta-Analysis and Meta-Regression

A widely accepted concept in perinatal medicine is that boys are more susceptible than girls to complications of prematurity. However, whether this ‘male disadvantage of prematurity’ also involves persistent patent ductus arteriosus (PDA) has been scarcely investigated. Our aim was to conduct a systematic review and meta-analysis on studies addressing sex differences in the risk of developing PDA among preterm infants. We also investigated whether the response to pharmacological treatment of PDA differs between boys and girls. PubMed/Medline and Embase databases were searched. The random-effects male/female risk ratio (RR) and 95% confidence interval (CI) were calculated. We included 146 studies (357,781 infants). Meta-analysis could not demonstrate sex differences in risk of developing any PDA (37 studies, RR 1.03, 95% CI 0.97 to 1.08), hemodynamically significant PDA (81 studies, RR 1.00, 95% CI 0.97 to 1.02), or in the rate of response to pharmacological treatment (45 studies, RR 1.01, 95% CI 0.98 to 1.04). Subgroup analysis and meta-regression showed that the absence of sex differences was maintained over the years and in different geographic settings. In conclusion, both the incidence of PDA in preterm infants and the response rate to pharmacological treatment of PDA are not different between preterm boys and girls.

Update on shunt closure in neonates and infants

Introduction: Cardiac defects that result in shunting are the most common types of congenital heart anomalies. Although these lesions can be simple, they can cause significant hemodynamic changes and can be challenging to manage in neonates and infants. Over the recent decades, the development of new transcatheter techniques and devices has made it safe and feasible to manage such defects when indicated, even in the smallest of patients. Understanding these interventional procedures is essential in order to manage those patients.Areas covered: In this article, we review the techniques and experience for closure of atrial septal defects, ventricular septal defects, patent ductus aarteriosus,as well as coronary arteriovenous malformations and fistulas in neonates and infants. Literature review of PubMed articles was performed through January 2021, with focus on the latest data and results of the usage of interventional techniques in treating these lesions specifically in this age-group.Expert opinion: Significant shunting lesions can be particularly challenging to manage in neonates and infants. Newer lower profile devices will likely continue to be developed in the future, allowing their use for transcatheter interventions in even smaller patients and those with more complex anatomy.

Clinical validity of systemic arterial steal among extremely preterm infants with persistent patent ductus arteriosus

OBJECTIVE

Investigate relevance of diastolic flow abnormalities in celiac trunk (aCT) and middle cerebral artery (aMCA) among preterms with persistent hemodynamically significant patent ductus arteriosus (phsPDA, diameter ≥ 1.5 mm, and age ≥ 7 days).

STUDY DESIGN

Five hundred fifteen echocardiograms from 156 neonates born <28 weeks gestation age (GA) were analyzed retrospectively. Infants with aCT or aMCA at any time were compared with the rest. Separate comparisons were performed for aCT and aMCA. Primary outcome was composite of death, chronic lung disease (CLD), or necrotizing enterocolitis ≥ stage 2. Logistic regression was used to adjust for confounders.

RESULT

Mean (SD) weight and GA were 820(214) g and 25.2(1.3) weeks. aMCA, but not aCT, was associated with primary outcome [adjusted odds ratio 2.17, 95% CI: 1.01-4.67] and CLD [2.20 (0.99-4.87)].

CONCLUSION

aMCA may be a valid marker for defining the clinical significance of phsPDA in preterm neonates. aCeT may be of limited value in selecting patients for treatment.

Resolution of neonatal posthemorrhagic ventricular dilation coincident with patent ductus arteriosus ligation: case report

Preterm infants commonly present with a hemodynamically significant patent ductus arteriosus (hsPDA). The authors describe the case of a preterm infant with posthemorrhagic ventricular dilation, which resolved in a temporally coincident fashion to repair of hsPDA. The presence of a PDA with left-to-right shunting was confirmed at birth on echocardiogram and was unresponsive to repeated medical intervention. Initial cranial ultrasound revealed periventricular-intraventricular hemorrhage. Follow-up serial ultrasound showed resolving intraventricular hemorrhage and progressive bilateral hydrocephalus. At 5 weeks, the ductus was ligated with the goal of improving hemodynamic stability prior to CSF diversion. However, neurosurgical intervention was not required due to improvement of ventriculomegaly occurring immediately after PDA ligation. No further ventricular dilation was observed at the 6-month follow-up.Systemic venous flow disruption and abnormal patterns of cerebral blood circulation have been previously associated with hsPDA. Systemic hemodynamic change has been reported to follow hsPDA ligation, although association with ventricular normalization has not. This case suggests that the unstable hemodynamic environment due to left-to-right shunting may also impede CSF outflow and contribute to ventriculomegaly. The authors review the literature surrounding pressure transmission between a PDA and the cerebral vessels and present a mechanism by which PDA may contribute to posthemorrhagic ventricular dilation.

Amplatzer Piccolo Occluder clinical trial for percutaneous closure of the patent ductus arteriosus in patients ≥700 grams

Objectives

Characterize the safety and effectiveness of the Amplatzer Piccolo Occluder for patent ductus arteriosus (PDA) closure.

Background

The presence of a hemodynamically significant PDA has been associated with an increased risk of morbidity and mortality in children born premature.

Methods

This was a single arm, prospective, multicenter, non‐randomized study to evaluate the Amplatzer Piccolo Occluder to treat PDA in patients ≥700 g. From June 2017 to February 2019, 200 patients were enrolled at nine centers, with 100 patients weighing ≤2 kg. Primary effectiveness endpoint was the rate of PDA closure at 6‐month follow‐up. Primary safety endpoint was the rate of major complications through 6 months. Secondary endpoint was rate of significant pulmonary or aortic obstruction through 6 months' follow‐up.

Results

The implant success rate was 95.5% (191/200) overall and 99% in patients ≤2 kg (99/100). The primary effectiveness endpoint was achieved in 99.4% of implanted patients. Four patients experienced a primary safety endpoint event (2 transfusions, 1 hemolysis, and 1 aortic obstruction). There were no branch pulmonary artery obstructions. Five patients, all ≤2 kg, were noted to have worsening of tricuspid regurgitation (TR) after the procedure. None of the TR incidences manifested clinically. The Amplatzer Piccolo Occluder received FDA approval in January 2019 and became the first device approved for PDA closure in patients ≥700 g.

Conclusions

This study supports the safety and effectiveness of the Amplatzer Piccolo Occluder, particularly in patients between 700 g and 2 kg where there is currently a significant unmet need in the United States. ClinicalTrials.gov identifier: NCT03055858.

Comparison of the efficacy and safety of indomethacin, ibuprofen, and paracetamol in the closure of patent ductus arteriosus in preterm neonates - A randomized controlled trial

INTRODUCTION

In this prospective study, we compared the efficacy and safety of ibuprofen, indomethacin, and paracetamol in the closure of patent ductus arteriosus (PDA) in preterm neonates.

MATERIALS AND METHODS

This randomized prospective study was conducted in the Division of Pediatric Cardiology, M. D. M and Umaid Hospital, Jodhpur. A total of 105 preterm neonates with gestational age <37 weeks and hemodynamically significant PDA (hs-PDA) diagnosed clinically and confirmed by echocardiography were enrolled. All neonates were randomly assigned in a ratio of 1:1:1 to oral indomethacin (Group A, 3 doses at an interval of 12 h with a starting dose of 0.2 mg/kg), oral ibuprofen (Group B, 10 mg/kg ibuprofen followed by 5 mg/kg/day for 2 days), or IV paracetamol (Group C, 15 mg/kg every 6 hourly for 3 consecutive days). After the completion of the first course, neonates were assessed clinically as well as by echocardiography to confirm PDA closure. If PDA remained open, the second course of the same drug was given and repeat assessment was done within 24 h of the last dose. In addition to an echocardiographic examination, complete blood counts, renal and liver function tests were performed.

RESULTS

Our study shows that there was no significant difference observed in PDA closure among all the three treatment groups after the completion of two courses of treatment. The cumulative rate of PDA closure was 68% in the indomethacin group, 77.14% in the ibuprofen group, and 71.43% in the paracetamol group (P = 0.716). There were no significant changes found in Hb, platelet, blood urea nitrogen (BUN), creatinine, and liver enzymes after treatment in the paracetamol group (P > 0.05). BUN and serum creatinine levels were significantly increased after treatment in indomethacin and ibuprofen groups (P < 0.0001 and P < 0.05, respectively).

CONCLUSION

Our study shows that IV paracetamol is as effective as indomethacin and ibuprofen in promoting the closure of hs-PDA in premature infants with a better safety profile.

Diagnostic and predictive value of Doppler ultrasound for evaluation of the brain circulation in preterm infants: a systematic review

INTRODUCTION

Very and extremely preterm infants frequently have brain injury-related long-term neurodevelopmental problems. Altered perfusion, for example, seen in the context of a hemodynamically significant patent ductus arteriosus (PDA), has been linked to injury of the immature brain. However, a direct relation with outcome has not been reviewed systematically.

METHODS

A systematic review was conducted to provide an overview of the value of different cerebral arterial blood flow parameters assessed by Doppler ultrasound, in relation to brain injury, to predict long-term neurodevelopmental outcome in preterm infants.

RESULTS

In total, 23 studies were included. Because of heterogeneity of studies, a meta-analysis of results was not possible. All included studies on resistance index (RI) showed significantly higher values in subjects with a hemodynamically significant PDA. However, absolute differences in RI values were small. Studies using Doppler parameters to predict brain injury and long-term neurodevelopmental outcome were inconsistent.

DISCUSSION

There is no clear evidence to support the routine determination of RI or other Doppler parameters in the cerebral arteries to predict brain injury and long-term neurodevelopmental outcome in the preterm infant. However, there is evidence that elevated RI can point to the presence of a hemodynamically significant PDA.

New Patent Ductus Arteriosus Closure Devices and Techniques

Patent ductus arteriosus (PDA) in extremely low-birth-weight infants puts this vulnerable population at high risks of morbidity and mortality. Inclusion of a multidisciplinary team and newly available transcatheter PDA occlusion devices in the management of these infants can mitigate those risks and promote better long-term outcomes. It is important that specific techniques with venous-only approach outlined in this article be followed to achieve optimal results.

Risk factors for intraventricular hemorrhage in premature infants in the central region of Saudi Arabia

Background

Intraventricular hemorrhage (IVH) is a serious complication of premature (<32 weeks) deliveries, especially in very-low-birth-weight (VLBW; <1500 g) neonates. Infants developing severe IVH are more prone to long-term developmental disabilities. Although 62%–79% of women in Saudi Arabia receive antenatal steroids, IVH incidence remains high. We analyzed the risk factors for IVH in preterm VLBW neonates in the central region of Saudi Arabia.

Methods

We included premature infants with IVH (n = 108) and gestational age- and birth weight-matched control group infants (n = 108) admitted to our neonatal intensive care unit. Cases were divided into mild (grades I and II; n = 56) and severe (grades III and IV; n = 52) IVH groups. Association of IVH with risk factors in the first week of life was investigated.

Results

The following risk factors were associated with severe IVH: lack of antenatal steroid administration (P < .001), pulmonary hemorrhage (P = .023), inotrope use (P = .032), neonatal hydrocortisone administration (P = .001), and patent ductus arteriosus (PDA) (P = .005). Multivariable logistic regression analysis revealed the following to be significant: lack of antenatal dexamethasone (adjusted odds ratio [aOR]: 0.219, 95% confidence interval [95% CI] 0.087–0.546), neonatal hydrocortisone administration (aOR: 3.519, 95% CI 1.204–10.281), and PDA (aOR: 2.718, 95% CI 1.024–7.210). Low hematocrit in the first 3 days of life was significantly associated with severe IVH (all P < .01).

Conclusions

Failure to receive antenatal dexamethasone, PDA, hydrocortisone administration for neonatal hypotension, and low hematocrit in the first 3 days of life was associated with severe IVH in VLBW neonates. Clinicians and healthcare policy makers should consider these factors during decision-making.

Changes in hemodynamics, cerebral oxygenation and cerebrovascular reactivity during the early transitional circulation in preterm infants

BACKGROUND

Changes in systemic and cerebral hemodynamics in preterm infants during early transitional circulation are complex and may differ between infants with or without intraventricular hemorrhage (IVH).

METHOD

In total, 43 infants born at median (range) 25 + 5 (23 + 3-31) had continuous near-infrared spectroscopy (NIRS) monitoring of tissue oxygenation index (TOI) and cerebrovascular reactivity within the first 48 h of life. Measurements of left and right cardiac outputs (LVO, RVO) and patent ductus arteriosus (PDA) were collected at 6, 12, 24, and 48 h of life.

RESULTS

LVO increased within the first 48 h in the IVH (P = 0.007) and no-IVH (P < 0.001) groups. The pattern of change in LVO and RVO was not different between these two groups. TOI was lower in the IVH (P < 0.001) group. A positive correlation between TOI and LVO (P = 0.003) and a negative correlation between the tissue oxygen reactivity index (TOx) and LVO (P = 0.04) were observed at 24 h of life in the IVH group. PDA diameter was not different between IVH groups at any time interval.

CONCLUSION

Cerebral oxygenation was lower and cerebrovascular reactivity was passive to systemic blood flow at 24 h in infants who developed an IVH.

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

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

Practice variation in the management of patent ductus arteriosus in extremely low birth weight infants in the United States: Survey results among cardiologists and neonatologists

BACKGROUND

Patent ductus arteriosus (PDA) is highly prevalent in extremely low birth weight (ELBW), preterm infants. There are diverse management approaches for the PDA in ELBW infants. The objectives of this research were to identify current PDA management practices among cardiologists and neonatologists in the United States, describe any significant differences in management, and describe areas where practices align.

METHODS

A survey of 10 questions based on the management of PDA in ELBW infants was conducted among 100 prominent neonatologists from 74 centers and 103 prominent cardiologists from 75 centers. Among the cardiologists, approximately 50% were interventionists who perform transcatheter PDA closures (TCPC). Fisher's exact test was performed to compare practice variations among neonatologists and cardiologists. A potentially biased audience including a combination of health care providers belonging to cardiology, neonatology, and surgery were also surveyed during the International PDA Symposium. The results of this survey were not included for statistical comparison, due to this audience being potentially influenced by the Symposium.

RESULTS

Statistically significant differences were identified between neonatologists and cardiologists regarding the impact of PDA closure on morbidity and mortality, with 80% cardiologists responding that it does vs 54% of neonatologists (P < 0.001), the need for PDA closure (P < .001), and the preferred method of PDA closure if indicated (P < .001). There was agreement between neonatologists and cardiologists on symptomatic therapy; however more neonatologists favored watchful waiting over intervention in contrast to more cardiologists favoring intervention over observation (77% vs 95%, P < .001). Survey responses also identified a need for further training and research on TCPC.

CONCLUSION

Neonatologists and cardiologists have notable differences in managing PDA, and continued discussion across cardiology and neonatology has the potential to facilitate more of a consensus on best management practices. Further investigation is needed to identify outcomes in transcatheter PDA closure, particularly in ELBW infants.

Reopening of the ductus arteriosus in preterm infants; Clinical aspects and subsequent consequences

OBJECTIVE

Patent ductus arteriosus is a common problem frequently encountered in preterm infants. We aimed to study the risk factors associated with reopening of patent ductus arteriosus and their short term outcomes in preterm infants.

METHODS

A total of 162 preterm infants born between November 2013 and December 2015 with gestaional age less than 32 weeks and treated for hemodynamically significant patent ductus arteriosus are included in our study.

RESULTS

113(69.8%) showed permanent closure and 49(30.2%) infants revealed symptoms of reopening after effective closure of patent ductus arteriosus. Low birth weight and small gestational age were more common in reopening group. Multivariete analysis showed that sepsis and multiple courses of drug treatment were independent factors affecting reopening of hemodynamically significant patent ductus arteriosus (OR: 3.01, 95% CI 1.48-6.13, p = 0.002) and (OR: 2.67, 95% CI 1.23-5.82, p = 0.013) respectively. Reopened group had a remarkable higher rate of developing necrotising nnterocolitis, bronchopulmonary dysplasia and retinopathy of prematurity than the closed group. (16.3% vs 4.4%, p = 0.01, 55.1% vs 28.3%, p = 0.001 and 55.1% vs 23.0%, p = 0.0001 respectively).

CONCLUSION

Late neonatal sepsis and the need of multiple drug courses to close patent ductus arteriosus are risk factors affecting the reopening of patent ductus arteriosus in preterm infants.

The effect of combined therapy for treatment of monotherapy-resistant PDA in preterm infants

Objective: Hemodynamically significant PDA (hsPDA) is one of the most common problems in preterm infants. This study was conducted to investigate the effect of combined pharmacological (paracetamol + ibuprofen) therapy on monotherapy-resistant hsPDA in infants. Subject and methods: The study included infants with persistent hsPDA, unresponsive to monotherapy. Combined treatment (paracetamol + ibuprofen) was started as paracetamol at a dose of 15 mg/kg every 6 hours for 5 days, and ibuprofen at an initial dose of 10 mg/kg followed by 5 mg/kg at 24 and 48 hours. Echocardiographic evaluation was performed at 2 days after the end of treatment. If hsPDA persisted after the combined treatment, a surgical PDA ligation was considered. Results: A total of 12 infants were enrolled and 9 infants (75%) with monotherapy-resistant PDA were successfully treated with combined therapy. In three patients, no response was obtained to the combined treatment so surgical ligation was applied. Conclusions: Combined therapy may be a useful treatment option for monotherapy-resistant hsPDA in preterm infants. Before surgical ligations, this combined therapy option should be considered.

Intraoperative High-Frequency Jet Ventilation Is Equivalent to Conventional Ventilation During Patent Ductus Arteriosus Ligation

Background:

Patent ductus arteriosus (PDA) treatment is typically pharmacologic, but if unsuccessful, surgical ligation is commonly performed. High-frequency jet ventilation (HFJV) is used at the University of Iowa Stead Family Children’s Hospital for extremely low birth weight infants. Historically, neonates requiring PDA ligation were temporarily transferred to conventional ventilation (CV) prior to surgery.

Objective:

The objective of this study was to determine whether conversion was necessary.

Methods:

This retrospective cohort analysis examined outcomes following PDA ligation from 2014 to 2016 at the University of Iowa’s Stead Family Children’s Hospital. Infants who were transferred to CV prior to surgery and returned to HFJV postprocedure are referred to as the CV cohort. The HFJV cohort infants remained on HFJV throughout.

Results:

We found no significant increases in morbidity or mortality with the use of intraoperative HFJV and potentially show some benefit through greater reduction in serum CO2.

Conclusions:

Mode of ventilation during PDA ligation does not affect surgical morbidity or mortality or short-term clinical outcomes. Conversion to CV from HFJV is not necessary.

Comparative study of the efficacy and safety of paracetamol, ibuprofen, and indomethacin in closure of patent ductus arteriosus in preterm neonates

In this prospective study, we compared the efficacy and side effects of indomethacin, ibuprofen, and paracetamol in patent ductus arteriosus (PDA) closure in preterm neonates. Three hundred preterm neonates with hemodynamically significant PDA (hs-PDA) admitted at our neonatal intensive care unit were enrolled in the study. They were randomized into three groups. Group I (paracetamol group) received 15 mg/kg/6 h IV paracetamol infusion for 3 days. Group II (ibuprofen group) received 10 mg/kg IV ibuprofen infusion followed by 5 mg/kg/day for 2 days. Group III (indomethacin group) received 0.2 mg/kg/12 h indomethacin IV infusion for three doses. Laboratory investigations such as renal function test, liver function test, complete blood count, and blood gases were conducted in addition to echocardiographic examinations. All investigations were done before and 3 days after treatment. There was no significant difference between all groups regarding efficacy of PDA closure (P = 0.868). There was a significant increase in serum creatinine levels and serum blood urea nitrogen (BUN) in the ibuprofen and indomethacin groups (P < 0.001). There was a significant reduction in platelet count and urine output (UOP) in both ibuprofen and indomethacin groups (P < 0.001). There was a significant increase in bilirubin levels in only the ibuprofen group (P = 0.003). No significant difference of hemoglobin (HB) level or liver enzymes in all groups (P > 0.05). Ventilatory settings improved significantly in patients with successful closure of PDA than those with failed PDA closure (P < 0.001).

CONCLUSION

Paracetamol is as effective as indomethacin and ibuprofen in closure of PDA in preterm neonates and has less side effects mainly on renal function, platelet count, and GIT bleeding. What is Known: • Hemodynamically significant patent ductus arteriosus has many complications for preterm and low birth weight neonates and better to be closed. Many drugs were used for medical closure of PDA e.g. indomethacin, ibuprofen and recently paracetamol. Many studies compare safety and efficacy of paracetamol with either indomethacin or ibuprofen. What is New: • It is the first large study that compares the efficacy and side effects of the three drugs in one study.

Cerebral oxygenation and echocardiographic parameters in preterm neonates with a patent ductus arteriosus: an observational study

BACKGROUND

A haemodynamically significant patent ductus arteriosus (hsPDA) is clinically suspected and confirmed by echocardiographic examination. A hsPDA decreases cerebral blood flow and oxygen saturation by the ductal steal phenomenon.

AIM

To determine the relationship between echocardiographic parameters, cerebral oxygenation and a hsPDA in preterm infants.

METHODS

380 preterm infants (<32 weeks gestational age) born between 2008 and 2010 were included. Blinded echocardiographic examination was performed on the second, fourth and sixth day after birth. Examinations were deblinded when hsPDA was clinically suspected. Regional cerebral oxygen saturation (rScO₂) was continuously monitored by near-infrared spectroscopy during 72 h after birth, and afterwards for at least 1 h before echocardiography. Echocardiographic parameters included ductal diameter, end-diastolic flow in the left pulmonary artery, left atrium/aorta ratio and ductal flow pattern.

RESULTS

rScO₂ was significantly related only to ductal diameter over time. Mixed modelling analysed the course of rScO₂ over time, where infants were divided into four groups: a closed duct, an open haemodynamically insignificant duct (non-sPDA), a hsPDA, which was successfully closed during study period (SC hsPDA) or a hsPDA, which was unsuccessfully closed during study period (UC hsPDA). SC hsPDA infants showed the highest rScO₂ on day 6, while UC hsPDA infants had the lowest rScO₂ values.

CONCLUSIONS

Ductal diameter is the only echocardiographic parameter significantly related to cerebral oxygenation over time. Cerebral oxygenation takes a different course over time depending on the status of the duct. Low cerebral oxygenation may be suggestive of a hsPDA.

Risk factors associated with post-hemorrhagic hydrocephalus among very low birth weight infants of 24-28 weeks gestation

OBJECTIVE

Post-hemorrhagic hydrocephalus (PHH) is associated with morbidity and mortality among very low birth weight (VLBW) infants. This study aimed to determine risk factors for PHH among VLBW infants with peri-intraventricular hemorrhage (PIVH).

STUDY DESIGN

This is a population-based cohort of VLBW infants of 24 to 28 weeks gestation, born in Israel from 1995 to 2012. Infants in whom a brain ultrasound was not performed before 28 days or with major congenital malformations were excluded. Univariate and multivariable analyses identified risk factors associated with PHH.

RESULTS

The final study cohort comprised 2811 infants with grade 2 or higher PIVH, of whom 610 (21.7%) developed PHH. PHH was independently associated with PIVH severity, with bilateral grade 3 PIVH and PIVH grade 3 and contralateral grade 4 having the highest risks (odds ratio (OR) 12.2, 95% confidence interval (CI) 8.56 to 17.4 and OR 13.7, 95% CI 9.4 to 20.1, respectively). Unilateral grade 3 or 4 PIVH's had moderately increased risks of PHH (OR 3.50, 95% CI 2.26 to 5.42 and OR 3.79, 95% CI 2.35 to 6.12, respectively). PHH was independently associated with increasing gestational age (GA) and with neonatal morbidities including patent ductus arteriosus (OR 1.47, 95% CI 1.15 to 1.88 if medically treated and OR 3.01, 95% CI 2.11 to 4.29 if surgically treated), sepsis (OR 1.79, 95% CI 1.44 to 2.22) and necrotizing enterocolitis (OR 1.60, 95% CI 1.18 to 2.17).

CONCLUSIONS

Among VLBW infants with PIVH, PHH was independently associated with PIVH severity group, increasing GA and acute neonatal morbidities. Unilateral grade 3 or 4 PIVH was associated with a moderate risk of developing PHH compared with bilateral severe hemorrhages.

Neurodevelopmental Outcomes of Premature Infants Treated for Patent Ductus Arteriosus: A Population-Based Cohort Study

OBJECTIVE

To compare neurodevelopmental outcomes of extremely preterm infants diagnosed with patent ductus arteriosus (PDA) who were treated medically or surgically and those who were not diagnosed with PDA or who did not undergo treatment for PDA.

STUDY DESIGN

This retrospective population-based cohort study used data from a geographically defined area in New South Wales and the Australian Capital Territory served by a network of 10 neonatal intensive care units. Patients included all preterm infants born at <29 completed weeks of gestation between 1998 and 2004. Moderate/severe functional disability at 2-3 years corrected age was defined as developmental delay, cerebral palsy requiring aids, sensorineural or conductive deafness (requiring bilateral hearing aids or cochlear implant), or bilateral blindness (best visual acuity of <6/60).

RESULTS

Follow-up information at age 2-3 years was available for 1473 infants (74.8%). Compared with infants not diagnosed with a PDA or who did not receive PDA treatment for PDA, those with medically treated PDA (aOR, 1.622; 95% CI, 1.199-2.196) and those with surgically treated PDA (aOR, 2.001; 95% CI, 1.126-3.556) were at significantly greater risk for adverse neurodevelopmental outcomes at age 2-3 years.

CONCLUSION

Our results demonstrate that treatment for PDA may be associated with a greater risk of adverse neurodevelopmental outcome at age 2-3 years. This was particularly so among infants born at <25 weeks gestation. These results may support permissive tolerance of PDAs; however, reasons for this association remain to be elucidated through carefully designed prospective trials.

Head Position Change Is Not Associated with Acute Changes in Bilateral Cerebral Oxygenation in Stable Preterm Infants during the First 3 Days of Life

OBJECTIVE

Several recent intraventricular hemorrhage prevention bundles include midline head positioning to prevent potential disturbances in cerebral hemodynamics. We aimed to study the impact of head position change on regional cerebral saturations (SctO2) in preterm infants (< 30 weeks gestational age) during the first 3 days of life.

STUDY DESIGN

Bilateral SctO2 was measured by near-infrared spectroscopy. The infant's head was turned sequentially to each side from midline (baseline) in 30-minute intervals while keeping the body supine. Bilateral SctO2 before and after each position change were compared using paired t-test.

RESULTS

In relatively stable preterm infants (gestational age 26.5 ± 1.7 weeks, birth weight 930 ± 220 g; n = 20), bilateral SctO2 remained within normal range (71.1-75.3%) when the head was turned from midline position to either side.

CONCLUSION

Stable preterm infants tolerated brief changes in head position from midline without significant alternation in bilateral SctO2; the impact on critically ill infants needs further evaluation.

Patent ductus arteriosus in preterm infants is associated with cardiac autonomic alteration and predominant parasympathetic stimulation

BACKGROUND

Hemodynamic disorders in patent ductus arteriosus (PDA) may alter the stimulation of the autonomic nervous system.

AIM

The objective of this study was to analyze the orthosympathetic-parasympathetic balance in preterm infants with PDA.

STUDY DESIGN AND SUBJECTS

Patients were included from consecutive admissions to Amiens University Hospital from 2009 to 2011. We defined a PDA group and a Control group (echographic criteria). For each patient, three 4-minutes segments of ECG were recorded during quiet sleep and the RR chronologic series were extracted, and spectral (Fourier Transform) and time-domain analyses were performed. For each parameter of heart rate variability (HRV), average of three measures was determined and analysed.

RESULTS

Forty-four patients were included for analysis. The total HRV power, LF/HF ratio and SDNN were lower in the PDA group (n = 22, gestational age 28.2 w ± 1.9) than in the Control group (n = 22, gestational age 28.8 w ± 2). The decrease in LF power destabilized the autonomic balance in favour of parasympathetic stimulation. After adjustment for postconceptional age, PDA was still associated with parameters of autonomic neural stimulation.

CONCLUSION

These results suggest association of PDA with predominance of parasympathetic stimulation in preterm infants. The mechanisms of homeostasis in patients with PDA are very complex and involve both circulatory adaptations and control by autonomic pathway. If confirmed, our results could be interesting for future researches aiming to verify the interest of new targeted therapies for the management of PDA.

It is not the ride: inter-hospital transport is not an independent risk factor for intraventricular hemorrhage among very low birth weight infants

OBJECTIVE

The purpose of this study was to evaluate the relationship between intraventricular hemorrhage (IVH), inter-hospital transport and known potential risk factors for IVH.

STUDY DESIGN

Very low birth weight (VLBW <1500 g) infants admitted to a large regional neonatal intensive care unit within 48 h of life from 2005 to 2010 were identified. Logistic regression and proportional odds logistic regression models were used to compare inborn versus outborn patients with respect to IVH (any vs none) and IVH grade, respectively. Logistic regression was used to quantify the association between outborn status and mortality.

RESULT

A total of 758 infants were included in the study (inborn=568, outborn=190). Outborn infants were found to have greater IVH severity than inborn (odds ratio (OR): 1.52; P=0.012). After accounting for 20 clinical and demographic variables in a multivariable model, the association between outborn status and IVH lacked statistical significance (OR: 1.14; P=0.56). Significant predictors of IVH grade included vaginal delivery (OR: 2.16; P<0.001), patent ductus arteriosus (OR: 1.65; P=0.005), 5-min Apgar (OR: 0.85; P=0.005) and gestational age (OR: 0.98; P=0.012). Sixty-nine (9.1%) of the infants died. After adjusting for potential confounders, the relationship between mortality and outborn status was not significant (OR:1.26; P=0.516). Significant predictors of mortality included gestational age (OR: 1.03; P=0.04) and 5-min Apgar (OR:1.22; P=0.02).

CONCLUSION

Although VLBW infants transported during the first 2 days of life have higher rates of IVH than infants born at a tertiary care facility, this relationship may be explained by associations with underlying clinical variables rather than transport itself.

Early echocardiographic prediction of ductal closure in neonates ≤ 30 weeks gestation

OBJECTIVE

To determine the accuracy of the patent ductus arteriosus:left pulmonary artery ratio (PDA:LPA) on echocardiogram (ECHO) at 3-day postnatal in predicting spontaneous PDA closure in neonates ≤ 30 weeks gestational age (GA).

STUDY DESIGN

ECHOs were performed at 72 h to characterize PDA size as closed-to-small (PDA:LPA <0.5) or moderate-to-large (PDA:LPA ≥ 0.5) and at 10 days to determine spontaneous closure (defined as closed-to-small in the absence of medical and/or surgical treatment). Caretakers were blinded to results; treatment was based on standard care. Neonates were prospectively enrolled and stratified: <27 weeks (n=31) and 27 to 30 weeks (n=65).

RESULT

Neonates <27 weeks with closed-to-small PDAs had 60% spontaneous closure vs 9% when moderate-to-large (positive predictive value (PPV) 60%, negative predictive value (NPV) 91%). Neonates 27 to 30 weeks had 95% spontaneous closure vs 27%, respectively (PPV 95%, NPV 73%). Inter-observer variability for the initial ECHO was 0.84.

CONCLUSION

PDA size defined by PDA:LPA at 3 days postnatal in combination with GA predicts spontaneous PDA closure.

The SafeBoosC phase II randomised clinical trial: a treatment guideline for targeted near-infrared-derived cerebral tissue oxygenation versus standard treatment in extremely preterm infants

Near-infrared spectroscopy-derived regional tissue oxygen saturation of haemoglobin (rStO2) reflects venous oxygen saturation. If cerebral metabolism is stable, rStO2 can be used as an estimate of cerebral oxygen delivery. The SafeBoosC phase II randomised clinical trial hypothesises that the burden of hypo- and hyperoxia can be reduced by the combined use of close monitoring of the cerebral rStO2 and a treatment guideline to correct deviations in rStO2 outside a predefined target range.

AIMS

To describe the rationale for and content of this treatment guideline.

METHODS

Review of the literature and assessment of the quality of evidence and the grade of recommendation for each of the interventions.

RESULTS AND CONCLUSIONS

A clinical intervention algorithm based on the main determinants of cerebral perfusion-oxygenation changes during the first hours after birth was generated. The treatment guideline is presented to assist neonatologists in making decisions in relation to cerebral oximetry readings in preterm infants within the SafeBoosC phase II randomised clinical trial. The evidence grades were relatively low and the guideline cannot be recommended outside a research setting.

Extremely low birth weight infants with patent ductus arteriosus: searching for the least invasiveness

Patent ductus arteriosus (PDA) is an important problem in premature infants. Extremely low birth weight infants (ELBWI) are so fragile with respect to surgical stress that minimally invasive procedures are required. We report 26 ELBWI cases with PDA who underwent surgical closure. All had failed indomethacin treatment, or it had been contraindicated. The mean gestational age at birth was 27 weeks (range, 24-38 weeks), and the mean birth weight was 960.96 g (range, 710-1440 g). The mean age at operation was 18.06 days (range, 7-34 days), and the mean body weight at operation was 989.42 g (range, 680-1460 g). There was no surgery-related mortality or morbidity. Our surgical procedures consisted of posterior muscle-sparing thoracotomy, clipping the PDA and no ligation, and closing the thorax without a tube thoracostomy. Muscle-sparing thoracotomy reduces the likelihood of long-term physical impairment and deformity, the clipping technique minimizes the dissection of surrounding PDA tissue, and the thorax is closed without a tube. Nursing care is simplified, costs are reduced, and the number of chest x-rays needed postoperatively is reduced. We believe that surgical closure of PDA without chest tube drainage can be accomplished safely in premature infants.

Cerebral autoregulation in neonates with a hemodynamically significant patent ductus arteriosus

OBJECTIVE

Very low birth weight (VLBW) preterm infants are at risk for impaired cerebral autoregulation with pressure passive blood flow. Fluctuations in cerebral perfusion may occur in infants with a hemodynamically significant patent ductus arteriosus (hsPDA), especially during ductal closure. Our goal was to compare cerebral autoregulation using near-infrared spectroscopy in VLBW infants treated for an hsPDA.

STUDY DESIGN

This prospective observational study enrolled 28 VLBW infants with an hsPDA diagnosed by echocardiography and 12 control VLBW infants without an hsPDA. Near-infrared spectroscopy cerebral monitoring was applied during conservative treatment, indomethacin treatment, or surgical ligation. A cerebral pressure passivity index (PPI) was calculated, and PPI differences were compared using a mixed-effects regression model. Cranial ultrasound and magnetic resonance imaging data were also assessed.

RESULTS

Infants with surgically ligated hsPDAs were more likely to have had a greater PPI within 2 hours following ligation than were those treated with conservative management (P=.04) or indomethacin (P=.0007). These differences resolved by 6 hours after treatment.

CONCLUSIONS

Cerebral autoregulation was better preserved after indomethacin treatment of an hsPDA compared with surgical ligation. Infants requiring surgical hsPDA ligation may be at increased risk for cerebral pressure passivity in the 6 hours following surgery.

Quantification of left-to-right shunt through patent ductus arteriosus by colour Doppler in children admitted for a device closure

PURPOSE

Our animal model suggests that quantification of ductal flow from colour Doppler pixels is possible. We aimed to clarify whether this method can be used to determine a clinically significant ductal shunt in children.

METHODS

We retrospectively quantified ductal flow from saved images from 20 children who had been admitted for device occlusion of patent ductus arteriosus. Colour Doppler images over the main stem of the pulmonary artery were obtained in longitudinal cross-sections. The colour pixel percentages during diastole, representing ductal flow, were correlated with the documented shunt, measured invasively according to Fick's principle.

RESULTS

The ratio of pulmonary to systemic flow correlated best with the sum of the percentages of green colour pixels (r = 0.73, r2 = 0.54, p < 0.001). When the shunt was 1.5:1 or more, 12 out of 13 infants had 50% or more of the region of interest covered with green pixels--sensitivity 92%, specificity 71%. The correlation between ductal diameter and pulmonary-to-systemic flow ratio was less significant (r = 0.6, r2 = 0.37, p < 0.03).

CONCLUSIONS

We conclude that clinically significant shunts with pulmonary-to-systemic flow ratio over 1.5 can be diagnosed with this method where neither the size of the patient nor echocardiographic settings seem to be critical. The method could be used to provide an objective indication for ductal closure, but further prospective studies in children are needed to verify the power of the method.

The relationship between systemic hemodynamic perturbations and periventricular-intraventricular hemorrhage--a historical perspective

Periventricular-intraventricular hemorrhage (PV-IVH) remains the major cause of injury to the developing brain. Predisposing factors include a germinal matrix with an immature vasculature, a pressure passive cerebral circulation, and hemodynamic perturbations in sick premature infants. Intact cerebral autoregulation has been documented in stable premature infants; however, it functions within a limited blood pressure range and is likely to be absent in the sick hypotensive infant, which increases the risk for PV-IVH with perturbations in blood pressure. The risk for PV-IVH is markedly increased in the absence of antenatal glucocorticoid exposure in the intubated low birthweight infant <1000 g with respiratory distress syndrome; +/- other complications. Although surfactant administration reduces the severity of respiratory distress syndrome, it has not led to a reduction in PV-IVH. Early postnatal administration of indomethacin has been associated with a reduction in PV-IVH, although this has not translated into long-term neurocognitive benefits.

Late morbidity during childhood and adolescence in previously premature neonates after patent ductus arteriosus closure

The health status of previously premature neonates after closure of a patent ductus arteriosus (PDA) was analyzed in childhood and adolescence. Physician questionnaires were used to study 180 hospital survivors among 210 consecutive premature neonates who underwent PDA closure between 1985 and 2005. Complete follow-up data were obtained for 129 patients (72%). During a median follow-up period of 7 years (range, 2-22 years), three late deaths (2.3%) had occurred. Only 45% of the patients were considered healthy. Morbidity included developmental delay (41.1%), pulmonary illness (12.4%), neurologic impairment (14.7%), hearing impairment (3.9%), gastrointestinal disease (3.1%), and thoracic deformity (1.2%). None of the adverse variables during the neonatal period (intraventricular hemorrhage, bradycardia apnea syndrome, bronchopulmonary dysplasia, pulmonary bleeding, hyaline membrane disease, artificial respiration time [continuous positive airway pressure + intubation], or necrotizing enterocolitis) statistically predicted respective system morbidity at the follow-up evaluation. Hyaline membrane disease (odds ratio, 2.5; p = 0.026) and longer hospitalization time (odds ratio, 1.2 days per 10 hospitalization days; p = 0.032) in the newborn period were significant predictors of an unhealthy outcome at the last follow-up evaluation. Survival until childhood after closure of a hemodynamically significant PDA in premature neonates is satisfactory. However, physical and neurodevelopmental co-morbidity persist for half of the patients, perhaps as a sequela of prematurity unrelated to ductus closure.

Is there an optimal timing for surgical ligation of patent ductus arteriosus in preterm infants?

BACKGROUND

We sought to define the variables associated with hospital outcome in preterm infants with patent ductus arteriosus (PDA) and identify the optimal timing for PDA closure to improve hospital outcome.

METHODS

Included were 201 premature babies (< or = 32 weeks gestational age), from January 2001 to June 2007, with PDA who received primary medical treatment with ibuprofen. Number of ibuprofen cycles, gestational age, body weight, and presence of symptomatic hypotension requiring vasoactive/inotropic drugs were related to hospital outcome, including hospital mortality, presence of necrotizing enterocolitis, acute renal failure, intraventricular hemorrhage, retinopathy and bronchopulmonary dysplasia at week 36. Data were analyzed with a logistic regression model.

RESULTS

Medical treatment was effective in 149 patients (75%), but 52 (25%) required surgical ligation after medical treatment failed. They had younger gestational age (25 weeks [IQR, 24 to 27 weeks] vs 27 weeks [IQR, 25 to 28 weeks], p < 0.0001), lower body weight at birth (730 g [IQR, 595 to 915 g] vs 840 g [IQR, 670 to 1016], p = 0.05), and a higher incidence of symptomatic hypotension (38 of 52 [73%] vs 56 of 149 [38%], p < 0.0001) than patients who responded to ibuprofen. More than two cycles of ibuprofen was significantly associated with an increased risk for bronchopulmonary dysplasia (odds ratio [OR], 2.81; p = 0.03) and acute renal failure (OR, 3.81; p = 0.09).

CONCLUSIONS

The prolonged patency of the ductus arteriosus in preterm infants is related to an increased morbidity. Surgical ligation of PDA is a safe and effective treatment and should be done soon after two complete cycles of ibuprofen, especially in selected patients, to improve clinical outcome.

Quantification of left to right shunt in patent ductus arteriosus by color Doppler

Ultrasound is a reliable tool to diagnose patent ductus arteriosus in premature infants but no reliable noninvasive method exists to quantify ductal flow. The aim of this study was to quantify the size of the shunt via persistent ductus arteriosus from pixel counts in color Doppler flow images. A cotton band was placed around the ductus arteriosus of newborn lambs to adjust the magnitude of flow. For flow measurements, ultrasonic transit time flow probes were applied around the ascending aorta and ductus arteriosus. Twenty-four different flow states were attained in four newborn lambs. An Acuson Sequoia scanner equipped with a 7 MHz transducer was used to register Doppler data and images with maximal color distribution during diastole in the pulmonary artery longitudinal sections (PALS). Each image-pixel was matched with the color velocity bar and the pixels were assigned to the corresponding flow velocity. The total area showing color relative to the area of the PALS correlated well with the amount of ductal flow (r = 0.87, r(2) = 0.75, p < 0.001). When Qp/Qs was >1.4:1, more than 40% of the area in PALS in diastole exhibited color information. Similarly, the color pixel velocities squared correlated with the size of the shunt. Quantification of the percentage of pixels in a color Doppler registration via a computer-based analysis shows a high correlation with the size of ductal shunting.

Ibuprofen lysine administration to neonates with a patent ductus arteriosus: effect on platelet plug formation assessed by in vivo and in vitro measurements

OBJECTIVE

Ibuprofen might have advantages over indomethacin, when used to effectuate closure of a neonate's patent ductus arteriosus (PDA). Several previous studies indicate that platelet plug formation is impaired after administration of indomethacin, but it is not clear whether a similar impairment occurs following ibuprofen dosing.

STUDY DESIGN

We performed template bleeding times and PFA-100 tests (platelet function analyzer) on 20 neonates who had a PDA, before and again at various preset intervals following ibuprofen dosing.

RESULT

Patients ranged from 23 to 40 weeks gestation and weighed 511 to 2566 g. Their first dose of ibuprofen was administered at 72 h (18 to 363 h) after birth (median, range). None of the subjects had clinical bleeding problems noted during the days they received ibuprofen dosing. The template bleeding times before dosing ranged from 135 to 450 s. Repeat tests were performed in groups of four, at 2 h, 4 to 6 h, 12 to 18 h, 24 h after the first dose, and at 2 h after the third dose of ibuprofen. No changes in bleeding times were detected. (P=0.299) A PFA-100 time was performed on all 20 patients before and again after the ibuprofen administration. However, 3 of the 40 tests were unsuccessful, because of microclots in the blood sample (n=1) or failure of the analyzer for an unspecified reason (n=2). Before the dosing the PFA-100 time ranged from 52 to 300 s. A paired t-test showed a slight but statistically significant lengthening in PFA-100 time after the ibuprofen administration (P=0.019). The correlation between the bleeding time and the PFA-100 was poor (R(2)=0.212, P=0.576).

CONCLUSION

On the basis of our present studies, we speculate that ibuprofen lysine administration to neonates with a PDA, when used according to the manufacturer's recommendations, has little adverse effect on platelet plug formation. This information might be a factor to consider when deciding whether to select indomethacin or ibuprofen for PDA closure.