Superior mesenteric artery blood flow velocities following medical treatment of a patent ductus arteriosus

[Expert consensus on enteral nutrition management for preterm infants in special situations (2024)]

Establishing enteral nutrition after the birth of preterm infants presents numerous challenges, particularly for those in special situations. Various disease factors and medical interventions impede the establishment of enteral feeding, leading to conflicts and controversies regarding feeding goals, feeding methods, and the challenges and solutions faced by these infants. A critical issue for clinical physicians is how to safely and promptly establish enteral nutrition to achieve full enteral feeding as quickly as possible. The consensus formulation working group, based on both domestic and overseas research, adopted the Grading of Recommendations Assessment, Development and Evaluation, and formed an expert consensus on enteral nutrition management for preterm infants in special situations. This consensus provides 14 recommendations for 9 common special situations, aiming to offer guidance on enteral nutrition management for preterm infants to improve their short and long-term outcomes. Citation:Chinese Journal of Contemporary Pediatrics, 2024, 26(7): 665-676.

Nutrition of the preterm infant with persistent ductus arteriosus: existing evidence and practical implications

The persistence of a patent ductus arteriosus (PDA) is a common condition in preterm infants with a prevalence inversely proportional to gestational age. PDA is associated with mild-to-severe gastrointestinal complications such as feeding intolerance, gastrointestinal perforation, and necrotizing enterocolitis, which represent a major challenge for the nutritional management in preterm infants. In this context, the Section on Nutrition, Gastroenterology and Metabolism and the Circulation Section of the European Society for Pediatric Research have joined forces to review the current knowledge on nutritional issues related to PDA in preterm infants. The aim of the narrative review is to discuss the clinical implications for nutritional practice. Because there is little literature on postnatal nutrition and PDA in preterm infants, further research with well-designed studies on this topic is urgently needed. Guidelines should also be developed to clearly define the implementation and course of enteral nutrition and the target nutritional intake before, during, and after pharmacologic or surgical treatment of PDA, when indicated. IMPACT: Persistent ductus arteriosus (PDA) is associated with gastrointestinal complications such as feeding intolerance, gastrointestinal perforation, and necrotizing enterocolitis, which pose a major challenge to the nutritional management of preterm infants. In PDA infants, fluid restriction may lead to inadequate nutrient intake, which may negatively affect postnatal growth and long-term health. The presence of PDA does not appear to significantly affect mesenteric blood flow and splanchnic oxygenation after enteral feedings. Initiation or maintenance of enteral nutrition can be recommended in infants with PDA.

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.

Feeding Strategies in Preterm Very Low Birth-Weight Infants: State-of-the-Science Review

BACKGROUND

Providing enteral feeds to preterm very low birth-weight (VLBW) infants is critical to optimize nutrition, enhance growth, and reduce complications. Protocols guiding feeding practices can improve outcomes, but significant variation exists between institutions, which may limit their utility. To be most effective, protocols should be based on the best available evidence.

PURPOSE

To examine the state of the science on several key components of feeding protocols for VLBW infants.

SEARCH STRATEGY

The authors searched PubMed, CINAHL, and EMBASE databases for terms related to feeding VLBW infants less than 32 weeks' gestational age, including initiation of feedings, rate of feeding advancement, timing of human milk (HM) fortification, and feeding during blood transfusions, when diagnosed with a patent ductus arteriosus (PDA) and during medical treatment of PDA closure.

RESULTS

Initiation of feeds within the first 3 days of life and advancement by 30 mL/kg/d may decrease time to attain full feeds without increasing complications. Insufficient evidence guides optimal timing of HM fortification, as well as feeding infants undergoing blood transfusions, infants diagnosed with a PDA, and infants receiving medical treatment of PDA closure.

IMPLICATIONS FOR PRACTICE

Integration of existing research regarding feeding initiation and advancement into feeding protocols may improve outcomes. Infants at highest risk of feeding-related complications may benefit from a personalized feeding approach.

IMPLICATIONS FOR RESEARCH

Additional research is needed to provide evidence concerning the optimal timing of HM fortification and feeding strategies for infants undergoing blood transfusions and those diagnosed with a PDA or receiving medical treatment of PDA closure to incorporate into evidence-based feeding protocols.

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.

Patent Ductus Arteriosus of the Preterm Infant

Postnatal ductal closure is stimulated by rising oxygen tension and withdrawal of vasodilatory mediators (prostaglandins, nitric oxide, adenosine) and by vasoconstrictors (endothelin-1, catecholamines, contractile prostanoids), ion channels, calcium flux, platelets, morphologic maturity, and a favorable genetic predisposition. A persistently patent ductus arteriosus (PDA) in preterm infants can have clinical consequences. Decreasing pulmonary vascular resistance, especially in extremely low gestational age newborns, increases left-to-right shunting through the ductus and increases pulmonary blood flow further, leading to interstitial pulmonary edema and volume load to the left heart. Potential consequences of left-to-right shunting via a hemodynamically significant patent ductus arteriosus (hsPDA) include increased risk for prolonged ventilation, bronchopulmonary dysplasia, necrotizing enterocolitis or focal intestinal perforation, intraventricular hemorrhage, and death. In the last decade, there has been a trend toward less aggressive treatment of PDA in preterm infants. However, there is a subgroup of infants who will likely benefit from intervention, be it pharmacologic, interventional, or surgical: (1) prophylactic intravenous indomethacin in highly selected extremely low gestational age newborns with PDA (<26 + 0/7 weeks' gestation, <750 g birth weight), (2) early targeted therapy of PDA in selected preterm infants at particular high risk for PDA-associated complications, and (3) PDA ligation, catheter intervention, or oral paracetamol may be considered as rescue options for hsPDA closure. The impact of catheter-based closure of hsPDA on clinical outcomes should be determined in future prospective studies. Finally, we provide a novel treatment algorithm for PDA in preterm infants that integrates the several treatment modalities in a staged approach.

To Feed or Not to Feed: A Critical Overview of Enteral Feeding Management and Gastrointestinal Complications in Preterm Neonates with a Patent Ductus Arteriosus

The management of enteral feeds in preterm infants with a hemodynamically significant patent ductus arteriosus (hs-PDA) is a major challenge for neonatologists due to the fear of gastrointestinal (GI) complications. This review aims to analyze the available evidence on the complex relation between the presence and management of PDA, enteral feeding practices, and GI outcomes in the preterm population. There is limited evidence, based on small and heterogeneous trials, that hs-PDA may affect the splanchnic hemodynamic response to enteral feeds. While the presence of PDA seems a risk factor for adverse GI outcomes, the benefits of feeding withholding during pharmacological PDA treatment are controversial. The lack of robust evidence in support of or against a timely feeding introduction or feeding withholding during pharmacological PDA closure in preterm neonates does not allow to draw any related recommendation. While waiting for further data, the feeding management of this population should be carefully evaluated and possibly individualized on the basis of the infants’ hemodynamic and clinical characteristics. Large, multicentric trials would help to better clarify the physiological mechanisms underlying the development of gut hypoperfusion, and to evaluate the impact of enteral feeds on splanchnic hemodynamics in relation to PDA features and treatment.

Management strategies for the preemie ductus

PURPOSE OF REVIEW

Patent ductus arteriosus (PDA) remains the most common cardiovascular condition afflicting neonates. Despite 5 decades of scientific inquiry pediatric cardiologists and neonatologists still cannot answer the simple question of which PDAs should be treated.

RECENT FINDINGS

Although the volume of the shunt is difficult to calculate, echocardiography, biochemical markers, and clinical exam can provide clues to the magnitude and physiologic consequences of the shunt. Epidemiologic data exists showing a positive relationship between a PDA and numerous morbidities. As a result, for most of the 20th and early 21st century, nearly all PDAs where indiscriminately considered to be hemodynamically significant and attempts to close it where initiated shortly after birth. However, no randomized trials of PDA closure have been able to show significant differences between affected and unaffected groups. In fact, surgical ligation has repeatedly been associated with increased morbidities and worse long-term neurodevelopmental outcomes. As a result, most clinicians favor a strategy of watchful waiting.

SUMMARY

In this review, we aim to summarize the scientific literature, along with some of the contemporary biases, that exist with regards to the pathophysiology, genetics, and treatment strategies for the neonatal PDA.

Enteral feeding during indomethacin treatment for patent ductus arteriosus: association with gastrointestinal outcomes

OBJECTIVE

Enteral feeds are often discontinued or reduced during indomethacin treatment for patent ductus arteriosus (PDA) in preterm neonates, but the clinical impact of this practice is unknown. The objective of this study was to study the associations between enteral feed volume at the time of indomethacin therapy in preterm neonates with PDA and subsequent gastrointestinal outcomes.

STUDY DESIGN

Retrospective cohort study. Single-center level III Neonatal Intensive Care Unit.

RESULTS

All consecutive preterm neonates who had received treatment with indomethacin for PDA over a 5-year period were included and categorized based on enteral feed volume exposure during treatment (Group A: nil per oral (NPO, N=229); Group B: ⩽60 ml kg(-1) day(-1) (N=142); Group C:>60 ml kg(-1) day(-1) (N=44)). Baseline characteristics and clinical outcomes were compared between the three groups. The primary outcome was necrotizing enterocolitis (NEC) ⩾stage IIa, while secondary outcomes included other gastrointestinal complications and common prematurity-related morbidities. Group C had a higher gestational age (mean±s.d.; A: 26.3±1.8; B: 26.1±1.8; C: 27.0±2.0 weeks), birth weight (A: 864±239; B: 847±202; C: 932±234 g) and postnatal age at the time of indomethacin treatment (A: 5.3±2.9; B: 7.2±4.9; C: 15.4±6.6 days). All groups had similar rates of the primary outcome NEC (A: 6.1%, B: 7.8% and C: 4.6%, respectively). They also had similar rates of the secondary outcomes with the exception of days to reach enteral feeds of 120 ml kg(-1) day(-1) (A: 22.8±8.5; B: 20.5±8.6; C: 16.8±7.7; P<0.05 for all inter-group comparisons). Secondary analysis including only those neonates who were not already NPO before indomethacin treatment (N=261) and categorized based on preemptive management (made NPO; enteral feed volume reduced; enteral feed volume unchanged/increased) also showed similar results.

CONCLUSIONS

This large retrospective study did not identify any association between enteral feed volumes during indomethacin treatment or preemptive reduction in enteral feeds and subsequent incidence of adverse gastrointestinal outcomes in preterm neonates. Preemptive reduction in enteral feed volume was associated with longer time to reach full enteral feeds.

What is new for patent ductus arteriosus management in premature infants in 2015?

PURPOSE OF REVIEW

A patent ductus arteriosus (PDA) in premature infants is common and is associated with a number of adverse outcomes. The purpose of this review is to discuss recent literature in PDA diagnosis and management.

RECENT FINDINGS

The diagnosis of a 'hemodynamically significant' PDA is challenging and a robust definition is lacking. The risks and benefits of therapies, either medical or surgical, designed to close the PDA, are controversial. Oral acetaminophen has gained increasing attention as an alternative pharmaceutical agent for PDA closure in premature infants, although safety concerns remain. Compared to surgical ligation, transcatheter PDA closure may be associated with less risk and fewer adverse events. Both aggressive and conservative management of PDA has similar clinically important outcomes, although the strength of evidence is derived mostly from cohort studies.

SUMMARY

Clinicians should weigh the potential adverse effects of pharmaceutical or surgical PDA closure against the likelihood of spontaneous closure. The infant population most likely to benefit from PDA closure remains ill-defined and clinical context is recommended.