Surgical ligation of patent ductus arteriosus in premature infants: trends and practice variation

Knowledge, Attitudes, and Practices Toward Retinopathy of Prematurity Among Neonatal Intensive Care Nurses: A Cross-sectional Study

It is important to study the awareness of retinopathy of prematurity (ROP) among neonatal care nurses in hospitals. Unfortunately, there is a lack of studies conducted among nurses on this subject in Palestine. Thus, this study purposed to assess the knowledge, attitudes, and practices toward ROP among neonatal intensive care nurses in Palestine. A cross-sectional was used to conduct this study. A convenience sampling method was utilized to recruit 289 neonate intensive care nurses working in private and governmental hospitals. The findings showed that around 48.0% of the nurses had low knowledge about preventing ROP. Most of the nurses (78%) reported a neutral attitude toward preventing ROP. Moreover, overall nurses' practices regarding ROP were fair (57.1%). There was a difference in practices regarding ROP according to the health sector (P < .05), in which the private sector had better practices compared to the governmental sector. Additionally, there was a significant difference in knowledge regarding ROP according to educational level (P < .05). Also, a significant difference was found in knowledge and practices regarding ROP according to nurses' experience. Attitudes and practices were the main significant predictors of knowledge (B = 0.153, P < .05; B = 0.172, P < .05, respectively). Knowledge and practices were the main predictors of attitudes (B = 0.126, P < .05; B = 469, P < .001), respectively. Knowledge, attitudes, and experience in neonate intensive care nurses were the main significant predictors of practices (B = 0.135, P < .05; B = 0.449, P < .001; B = 0.224, P < .05, respectively). It is necessary to develop an educational program and competency-based training programs for neonate intensive care nurses about ROP and implement preventive strategies.

Measuring gut perfusion and blood flow in neonates using ultrasound Doppler of the superior mesenteric artery: a narrative review

The gut is a relatively silent organ in utero but takes on a major role after birth for the absorption and digestion of feed for adequate nutrition and growth. The neonatal circulation undergoes a transition period after birth, and gut perfusion increases rapidly to satisfy the oxygen demand and consumption. If this process is compromised at any stage, preterm and fetal growth restricted infants are at particular risk of gut tissue injury secondary to hypoxia, leading to necrotizing enterocolitis. Feeding can also be a challenge in these high-risk groups due to gut dysmotility. Superior mesenteric artery (SMA) Doppler is a safe, bedside investigation that could rapidly aid clinicians with feeding strategies and in monitoring high-risk infants. This article aims to establish normal patterns of gut blood flow velocity in neonates using SMA Doppler and reviews how it might be used clinically in pathologic states.

Management of Patent Ductus Arteriosus in Premature Infants in 2020

The patent ductus arteriosus (PDA) is the most commonly found cardiac condition in neonates. While there have been several studies and thousands of publications on the topic, the decision to treat the PDA is still strongly debated among cardiologists, surgeons, and neonatologists. This is in part due to the shortage of long-term benefits with the interventions studied. Practice variations still exist within sub-specialties and centers. This article briefly summarizes the history, embryology and histology of the PDA. It also succinctly discusses the hemodynamic significance of a PDA which builds the framework to review all the available literature on PDA closure in premature infants, though not a paradigm shift just yet; it introduces transcatheter PDA closure (TCPC) as a possible armament to the clinician for this age-old problem.

A Matched Case Control Study of Surgically and Non-surgically Treated Patent Ductus Arteriosus in Extremely Pre-term Infants

Introduction: There are still uncertainties about the timing and indication for surgical ligation of patent ductus arteriosus (PDA) in pre-term infants, where lower gestational age (GA) usually is predictive for surgical treatment. Objective: Our aim was to assess differences in clinical characteristics and outcomes between surgically treated and matched non-surgically treated PDA in extremely pre-term infants. Methods: All extremely pre-term infants born 2010-2016 with surgically treated PDA (Ligated group; n = 44) were compared to non-surgically treated infants (Control group; n = 44) matched for gestational age (+/-1 week) and time of birth (+/-1 month). Perinatal parameters, echocardiographic variables, details of pharmacological PDA treatment, morbidity, and mortality were assessed. Result: Mean GA and birthweight were similar between the Ligated group (24⁺⁵ ± 1⁺³ weeks and 668 ± 170 g) and the Control group (24⁺⁵ ± 1⁺³ weeks and 704 ± 166 g; p = 1.000 and p = 0.319, respectively). Infants in the Ligated group had larger ductal diameters prior to pharmacological treatment, and lack of diameter decrease and PDA closure after treatment (p = 0.022, p = 0.043 and 0.006, respectively). Transfusions, post-natal steroids and invasive respiratory support were more common in the Ligated group. Except for a higher incidence of severe bronchopulmonary dysplasia (BPD) in the Ligated group there were no other differences in outcomes or mortality between the groups. Conclusion: Early large ductal diameter and reduced responsiveness to pharmacological treatment predicted the need for future surgical ligation in this matched cohort study of extremely pre-term infants where the effect of GA and differences in treatment strategies were excluded. Besides an increased incidence of severe BPD in the Ligated group, no other differences in morbidity or mortality were detected.

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.

Trends in transcatheter and operative closure of patent ductus arteriosus in neonatal intensive care units: Analysis of data from the Pediatric Health Information Systems Database

BACKGROUND

The risks and benefits of pharmacologic treatment and operative closure of patent ductus arteriosus (O-PDA) in premature infants remain controversial. Recent series have demonstrated the feasibility of transcatheter PDA closure (TC-PDA) in increasingly small infants. The effect of this change on practice has not been evaluated.

METHODS

A multicenter observational study of infants treated in neonatal intensive care units in hospitals contributing data to the Pediatric Health Information Systems Database from January 2007 to December 2017 was performed to study trends in the propensities for (1) mechanical closure of PDA and (2) TC-PDA versus O-PDA, as well as interhospital variation in practice.

RESULTS

A total of 6,214 subjects at 44 hospitals were studied (5% TC-PDA). Subject median gestational age was 25 weeks (interquartile range: 24-27 weeks). Median age at closure was 24 days (interquartile range: 14-36 days). The proportion of all neonatal intensive care unit patients undergoing either O-PDA or TC-PDA decreased (3.1% in 2007 and 0.7% in 2017, P < .001), whereas the proportion in which TC-PDA was used increased significantly (0.1% in 2007 to 29.0% in 2017). Case-mix-adjusted multivariable models similarly demonstrated increasing propensity to pursue TC-PDA (odds ratio [OR] 1.66 per year, P < .001) with acceleration of the trend after 2014 (OR 2.46 per year, P < .001) as well as significant practice variation (P < .001, median OR 4.6) across the study period.

CONCLUSIONS

In the face of decreasing closure of PDA, the use of TC-PDA increased dramatically with significant practice variability. This demonstrates that there is equipoise for potential clinical trials.

CYP2C9*2 is associated with indomethacin treatment failure for patent ductus arteriosus

Aims: To identify clinical andgenetic factors associated with indomethacin treatment failure in preterm neonates with patent ductus arteriosus (PDA). Patients & Methods: This is a multicenter cohort study of 144 preterm infants (22-32 weeks gestational age) at three centers who received at least one treatment course of indomethacin for PDA. Indomethacin failure was defined as requiring subsequent surgical intervention. Results: In multivariate analysis, gestational age (AOR 0.76, 95% CI 0.60-0.96), surfactant use (AOR 9.77, 95% CI 1.15-83.26), and CYP2C9*2 (AOR 3.74; 95% CI 1.34-10.44) were each associated with indomethacin failure. Conclusion: Age, surfactant use, and CYP2C9*2 influence indomethacin treatment outcome in preterm infants with PDA. This combination of clinical and genetic factors may facilitate targeted indomethacin use for PDA.

Population Pharmacokinetics and Dosing of Milrinone After Patent Ductus Arteriosus Ligation in Preterm Infants

OBJECTIVES

The postoperative course of patent ductus arteriosus ligation is often complicated by postligation cardiac syndrome, occurring in 10-45% of operated infants. Milrinone might prevent profound hemodynamic instability and improve the recovery of cardiac function in this setting. The present study aimed to describe the population pharmacokinetics of milrinone in premature neonates at risk of postligation cardiac syndrome and give dosing recommendations.

DESIGN

A prospective single group open-label pharmacokinetics study.

SETTINGS

Two tertiary care neonatal ICUs: Tallinn Children's Hospital and Tartu University Hospital, Estonia.

PATIENTS

Ten neonates with postmenstrual age of 24.6-30.1 weeks and postnatal age of 5-27 days undergoing patent ductus arteriosus ligation and at risk of postligation cardiac syndrome, based on echocardiographic assessment of left ventricular output of less than 200 mL/kg/min 1 hour after the surgery.

INTERVENTIONS

Milrinone at a dose of 0.73 μg/kg/min for 3 hours followed by 0.16 μg/kg/min for 21 hours. Four blood samples from each patient for milrinone plasma concentration measurements were collected.

MEASUREMENTS AND MAIN RESULTS

Concentration-time data of milrinone were analyzed with nonlinear mixed-effects modeling software (NONMEM Version 7.3 [ICON Development Solutions, Ellicott City, MD]). Probability of target attainment simulations gave a dosing schedule that maximally attains concentration targets of 150-250 μg/L. Milrinone pharmacokinetics was described by a one-compartmental linear model with allometric scaling to bodyweight and an age maturation function of glomerular filtration rate. Parameter estimates for a patient with the median weight were 0.350 (L/hr) for clearance and 0.329 (L) for volume of distribution. The best probability of target attainment was achieved with a loading dose of 0.50 μg/kg/min for 3 hours followed by 0.15 μg/kg/min (postmenstrual age < 27 wk) or 0.20 μg/kg/min (postmenstrual age ≥ 27 wk).

CONCLUSIONS

Population pharmacokinetic modeling and simulations suggest a slow loading dose followed by maintenance infusion to reach therapeutic milrinone plasma concentrations within the timeframe of the postligation cardiac syndrome.

Efficacy and Safety of Oral Paracetamol vs. Oral Ibuprofen in the Treatment of Symptomatic Patent Ductus Arteriosus in Premature Infants

BACKGROUND

The ductus arteriosus (DA) is situated between the aortic arch and the pulmonary artery in fetal circulation, and its closure is one of the most important changes required for the transition to extrauterine life. Prolonged duration of patent DA (PDA) impairs hemodynamics and contributes both to morbidity associated with prematurity and to mortality. Therefore, when best to initiate treatment and what drug to use as first-line treatment to close the ductus is important.

OBJECTIVE

The aim of this study was to compare the efficacy and side effects of the oral forms of ibuprofen and paracetamol and to contribute to the literature investigating the first drug to be selected in the medical treatment of PDA.

METHODS

This observational, retrospective cohort study was conducted in infants born at ≤ 28 weeks' gestation and admitted to our Neonatal Intensive Care Unit (Manisa Merkezefendi State Hospital, Manisa, Turkey) between February 2015 and April 2018. Included infants were born at ≤ 28 weeks' gestation, had PDA-related clinical findings and hemodynamically significant PDA on echocardiography, and received oral ibuprofen or oral paracetamol therapy as the closure treatment.

RESULTS

The most common clinical findings for the diagnosis of PDA were hyperdynamic circulation, tachycardia, and increased oxygen requirement. In total, 43 of the 51 (84.3%) premature infants in the ibuprofen group and 32 of the 36 (88.8%) in the paracetamol group achieved PDA closure after the first treatment cycle. There was no statistically significant difference between the two groups in terms of respiratory morbidity, renal and liver function, intraventricular hemorrhage, necrotizing enterocolitis, bronchopulmonary dysplasia, retinopathy of prematurity, length of hospital stay, and mortality.

CONCLUSIONS

Our results indicate that oral paracetamol was as effective as oral ibuprofen in the medical treatment of PDA. In addition, both drugs were considered well-tolerated in terms of effects on kidney, liver, and intestinal functions. Our results demonstrate that oral paracetamol can be used effectively and safely as the first-line treatment of PDA.

Turkish Neonatal Society guideline on the management of patent ductus arteriosus in preterm infants

Ductus arteriosus is a physiologic phenomenon in utero and it closes spontaneously in term babies. The closure is problematic in preterm infants due to the intrinsic properties of the preterm ductus arteriosus tissue. Although patent ductus arteriosus has been reported to be associated with many adverse outcomes in this population, treatment has not led to a decrease in outcomes such as bronchopulmonary dysplasia. Treatment modalities also have their own risks and restrictions. The aim of the "Turkish Neonatal Society guidelines for the management of patent ductus arteriosus in preterm babies" is to standardize the diagnosis and treatment of patent ductus arteriosus in preterm infants by combining the current scientific data and the resources of our country.

Long-Term Neurodevelopment of Low-Birthweight, Preterm Infants with Patent Ductus Arteriosus

OBJECTIVE

To evaluate whether the presence of patent ductus arteriosus (PDA) in preterm infants worsens long-term neurodevelopmental outcomes.

STUDY DESIGN

This was a secondary observational analysis of data from 1090 preterm low-birthweight infants in the Infant Health and Development Program (IHDP), a multicenter longitudinal cohort study of outcomes assessed from 3 to 18 years of age. Multivariable analysis was adjusted for IHDP treatment group (intervention or follow-up), birth weight, maternal race, maternal education, infant sex, maternal preconception weight, Home Observation Measurement of the Environment (HOME) total score at 12 months, neonatal health index, and gestational age.

RESULTS

Of the 1090 patients (49% male) included in the analysis, 135 had a PDA. Mean birth weight (1322 g vs 1871 g; P < .0001) and gestational age (30.2 weeks vs 33.4 weeks, P < .0001) were lower and mean ventilator days (11.8 vs 1.3; P < .0001), vasopressor use (12.6% vs 1.2%; P < .0001), and congestive heart failure (8.9% vs 0.1%; P < .0001) were higher in the PDA group. There were no differences between the PDA and no-PDA groups in maternal education level and HOME total score at age 12 months. Multivariable analysis demonstrated no between-group differences in cognitive development or behavioral competence at age 3, 8, and 18 years.

CONCLUSIONS

The presence of a PDA in moderately preterm, low-birthweight infants does not impact long-term neurodevelopmental outcomes.

Can lactate levels be used as a marker of patent ductus arteriosus in preterm babies?

OBJECTIVE

Serum lactate levels provide information on metabolic capacity at the cellular level. In addition, lactate reflects tissue perfusion and oxygenation status. The aim of this study was to determine the usefulness of high lactate levels as a marker in hemodynamically significant patent ductus arteriosus (hsPDA), which may lead to tissue perfusion defects.

METHODS

Preterm infants with gestational age ≤32 weeks and birthweight ≤1500 g were included. Lactate levels were determined at postnatal 48-72 hours before echocardiographic evaluation. Eligible infants were divided into two groups as infants with and without hsPDA. Cut-off values for lactate were taken as lactate >4 mmol/L, identified as a high lactate level. Infants were also divided into two groups according to lactate levels as group I: lactate levels >4 mmol/L and group II: lactate levels ≤4 mmol/L. Haemodynamic PDA and lactate levels were compared.

RESULTS

A total of 119 patients with gestational age ≤32 weeks and birthweight ≤1500 g were included in the study. Fifty patients had echocardiographic hsPDA and 69 patients had no PDA. Twelve (24%) of the patients with hsPDA and 22 (31.9%) of the non-hsPDA patients had a lactate level of 4 mmol/L (P = 0.392). There was no correlation between hsPDA presence and lactate levels (P = 0.35).

CONCLUSION

High lactate levels are multifactorial and usually indicate impairment of tissue perfusion. There are a number of factors that can lead to impaired tissue perfusion in preterm infants. For the first time in this study, it was shown that lactate levels did not significantly increase in the presence of hemodynamically significant PDA. This may be due to the fact that peripheral tissue perfusion in the presence of hemodynamic PDA does not deteriorate enough to cause an increase in anaerobic metabolism.

Changing patterns of patent ductus arteriosus surgical ligation in the United States

Optimal management of patent ductus arteriosus (PDA) is unclear. One treatment, surgical ligation, is associated with adverse outcomes. We reviewed data from the Kids' Inpatient Database (2000-2012) to determine if PDA ligation rates: (1) changed over time, (2) varied geographically, or (3) influenced surgical complication rates. In 2012, 47,900 infants <1500g birth weight were born in the United States, including 2,800 undergoing PDA ligation (5.9%). Ligation was more likely in infants <1000g (85.9% vs. 46.2%), and associated with necrotizing enterocolitis (59.2% vs. 37.5%), BPD (54.6% vs. 15.2%), severe intraventricular hemorrhage (16.4% vs. 5.3%), and hospital transfer (37.6% vs. 16.4%). Ligation rates peaked in 2006 at 87.4 per 1000 hospital births, dropping to 58.8 in 2012, and were consistently higher in Western states. Infants undergoing ligation were more likely to experience comorbidities. Rates of ligation-associated vocal cord paralysis increased over time (1.2-3.9%); however, mortality decreased (12.4-6.5%). Thus, PDA ligation has become less frequent, although infants being ligated are smaller and more medically complex. Despite increase in some complications, mortality rates improved perhaps reflecting advances in care.

Left vocal cord paralysis after patent ductus arteriosus ligation: A systematic review

CONTEXT

Extremely premature (EP) infants are at increased risk of left vocal cord paralysis (LVCP) following surgery for patent ductus arteriosus (PDA).

OBJECTIVE

A Systematical Review was conducted to investigate the incidence and outcomes of LVCP after PDA ligation in EP born infants.

DATA SOURCES

Searches were performed in Cochrane, Medline, Embase, Cinahl and PsycInfo.

STUDY SELECTION

Studies describing EP infants undergoing PDA surgery and reporting incidence of LVCP were included.

DATA EXTRACTION AND SYNTHESIS

Study details, demographics, incidence of LVCP, diagnostic method and reported outcomes were extracted. DerSimonian and Laird random effect models with inverse variance weighting were used for all analyses.

STUDY APPRAISAL

The Newcastle-Ottawa scale for observational studies was used for quality assessment.

RESULTS

21 publications including 2067 infants were studied. The overall pooled summary estimate of LVCP incidence was 9.0% (95% CI 5.0, 15.0). However, the pooled incidence increased to 32% when only infants examined with laryngoscopy were included. The overall risk ratio for negative outcomes was higher in the LVCP group (2.20, 95% CI 1.69, 2.88, p = 0.01) compared to the non-LVCP-group.

CONCLUSIONS

Reported incidence of LVCP varies widely. This may be explained by differences in study designs and lack of routine vocal cords postoperative assessment. LVCP is associated with negative outcomes in EP infants. The understanding of long-term outcomes is scarce. Routine laryngoscopy may be necessary to identify all cases of LVCP, and to provide correct handling for infants with LVCP.

Post-ligation cardiac syndrome is associated with increased morbidity in preterm infants

OBJECTIVE

The influence of post-ligation cardiac syndrome (PLCS), a complication of patent ductus arteriosus (PDA) ligations, on neonatal outcomes is unknown. The purpose of this study was to determine the risks of PLCS on severe pulmonary morbidity and severe retinopathy of prematurity (ROP).

STUDY DESIGN

Retrospective cohort study of infants who underwent a PDA ligation between 2006 and 2015. Data were collected on patients with and without PLCS. The primary outcome was the difference in severe bronchopulmonary dysplasia (BPD) between groups. Secondary outcomes included discharge with home oxygen and severe ROP.

RESULT

A total of 100 infants that underwent PDA ligation during the study period were included in the study; 31 (31%) neonates developed PLCS. In adjusted analysis, PLCS was associated with increased risk for severe BPD (RR 1.67, 95% CI: 1.15-2.42) and home oxygen therapy (RR: 1.47, 95% CI: 1.09-1.99) only. No association with severe ROP was seen (RR: 1.48; 95% CI: 0.87-2.52).

CONCLUSION

PLCS is associated with severe neonatal pulmonary morbidity, but not with severe ROP. Further investigation is warranted to validate these results.

Minimally Invasive Patent Ductus Arteriosus Ligation

A patent ductus arteriosus is a common condition, particularly in premature infants. Many spontaneously resolve but those that lead to clinical instability require closure. Conservative measures can be highly successful in selected groups. Surgical repair is effective and both open and minimally invasive approaches can be used. The minimally invasive approach may result in less long-term morbidity from a thoracotomy and may prove advantageous for these fragile infants, including less pain, shorter time on the ventilator, and shorter hospital stays.

Trends and variation in management and outcomes of very low-birth-weight infants with patent ductus arteriosus

BACKGROUND

We examined recent trends and interhospital variation in use of indomethacin, ibuprofen, and surgical ligation for patent ductus arteriosus (PDA) in very-low-birth-weight (VLBW) infants.

METHODS

Included in this retrospective study of the Pediatric Hospital Information System database were 13,853 VLBW infants from 19 US children's hospitals, admitted at age < 3 d between 1 January 2005 and 31 December 2014. PDA management and in-hospital outcomes were examined for trends and variation.

RESULTS

PDA was diagnosed in 5,719 (42%) VLBW infants. Cyclooxygenase inhibitors and/or ligation were used in 74% of infants with PDA overall, however studied hospitals varied greatly in PDA management. Odds of any cyclooxygenase inhibitor or surgical treatment for PDA decreased 11% per year during the study period. This was temporally associated with improved survival but also with increasing bronchopulmonary dysplasia, periventricular leukomalacia, retinopathy of prematurity, and acute renal failure in unadjusted analyses. There was no detectable correlation between hospital-specific changes in PDA management and hospital-specific changes in outcomes of preterm birth during the study period.

CONCLUSION

Use of cyclooxygenase inhibitors and ligation for PDA in VLBW infants decreased over a 10-y period at the studied hospitals. Further evidence is needed to assess the impact of this change in PDA management.

Retinopathy of prematurity: the need for prevention

More than 450,000 babies are born prematurely in the USA every year. The improved survival of even the most vulnerable low body weight preterm infants has, despite improving health outcomes, led to the resurgence in preterm complications including one of the major causes for blindness in children, retinopathy of prematurity (ROP). The current mainstay in ROP therapy is laser photocoagulation and the injection of vascular endothelial growth factor (VEGF) antibodies in the late stages of the disease after the onset of neovascularization. Both are proven options for ophthalmologists to treat the severe forms of late ROP. However, laser photocoagulation destroys major parts of the retina, and the injection of VEGF antibodies, although rather simple to administer, may cause a systemic suppression of normal vascularization, which has not been studied in sufficient depth. However, the use of neither VEGF antibody nor laser treatment prevents ROP, which should be the long-term goal. It should be possible to prevent ROP by more closely mimicking the intrauterine environment after preterm birth. Such preventive measures include preventing the toxic postbirth influences (eg, oxygen excess) as well as providing the missing intrauterine factors (eg, insulin growth factor 1) and are likely to also reduce other complications of premature birth as well as ROP. This review is meant to summarize the current knowledge on the prevention of ROP with a particular emphasize on the use of insulin growth factor 1 supplementation.