Parenteral Fish-Oil Lipid Emulsions in the Prevention of Severe Retinopathy of Prematurity: A Systematic Review and Meta-Analysis

ROP: 80 Years after Its Detection - Where Do We Stand and How Long Will We Continue to Laser?

BACKGROUND

Retinopathy of prematurity (ROP), a potentially blinding disease, is increasing worldwide because of the increased survival of extremely preterm and preterm infants born where oxygen monitoring and ROP screening programs are insufficient. Repeated retinal examinations are stressful for infants, and laser photocoagulation treatment for sight-threatening ROP is destructive. The use of anti-VEGF agents instead of lasers is widespread but requires a long-term follow-up because of late recurrence of the disease. In addition, the optimal anti-VEGF agent dosage and long-term systemic effects require further study.

SUMMARY

Interventions preventing ROP would be far preferable, and systemic interventions might promote better development of the brain and other organs. Interventions such as improved oxygen control, provision of fresh maternal milk, supplementation with arachidonic acid and docosahexaenoic acid, and fetal hemoglobin preservation by reducing blood sample volumes may help prevent ROP and reduce the need for treatment. Free readily available online tools to predict severe ROP may reduce unnecessary eye examinations and select, for screening, those at a high risk of needing treatment.

KEY MESSAGES

Treatment warranting ROP is a sign of impaired neurovascular development in the central nervous system. Preventative measures to improve the outcomes are available. Screening can be refined using tools that can predict severe ROP. Laser treatment and anti-VEGF agents are valuable treatment modalities that may complement each other in recurrent ROP.

Nutritional interventions to prevent retinopathy of prematurity

Very preterm infants are at high risk of growth failure. Poor weight gain is a prominent risk factor for retinopathy of prematurity (ROP) and optimizing nutrition could potentially promote growth and reduce ROP. Most infants at risk of ROP need parenteral nutrition initially and studies of enhanced parenteral provision of lipids and amino acids have suggested a beneficial effect on ROP. Higher amino acid intake was associated with lower incidence of hyperglycemia, a risk factor for ROP. For very preterm infants, providing unpasteurized fortified raw maternal breast milk appears to have a dose-dependent preventive effect on ROP. These infants become deficient in arachidonic acid (ArA) and docosahexaenoic acid (DHA) after birth when the maternal supply is lost. Earlier studies have investigated the impact of omega-3 fatty acids on ROP with mixed results. In a recent study, early enteral supplementation of ArA 100 mg/kg/d and DHA 50 mg/kg/d until term equivalent age reduced the incidence of severe ROP by 50%. IMPACT: Previous reviews of nutritional interventions to prevent morbidities in preterm infants have mainly addressed bronchopulmonary dysplasia, brain lesions and neurodevelopmental outcome. This review focusses on ROP. Neonatal enteral supplementation with arachidonic acid and docosahexaenoic acid, at levels similar to the fetal accretion rate, has been found to reduce severe ROP by 50% in randomized controlled trials.

Comparison of Glutathione Nanoparticles, CoEnzyme Q10, and Fish Oil for Prevention of Oxygen-Induced Retinopathy in Neonatal Rats

Notch ligands and receptors are important for cell specification and angiogenesis, but their role in oxygen-induced retinopathy (OIR) is not well studied. Delta-like ligand (DLL)-4/Notch inhibits angiogenesis, while Jagged-1/Notch promotes angiogenesis. We tested the hypothesis that early supplementation with antioxidants and/or fish oil curtails severe OIR by inducing DLL-4/Notch and reducing Jagged-1/Notch. Newborn rats were exposed to brief intermittent hypoxia (IH) during hyperoxia, during which they received daily oral supplements of (1) fish oil, (2) coenzyme Q10 (CoQ10) in olive oil (OO), (3) glutathione nanoparticles (nGSH), (4) fish oil + CoQ10, or (5) OO (controls) from birth (P0) to P14. At P14, the pups were placed in room air (RA) until P21, with no further treatment. Oxidative stress, apoptosis, ocular histopathology, and Notch signaling were assessed. Neonatal IH resulted in severe retinal damage consistent with retinopathy of prematurity (ROP). Retinal damage was associated with induced oxidative stress and Jagged-1/Notch signaling, as well as reduced DLL-4/Notch signaling. All treatments reversed these outcomes, but nGSH produced the most beneficial outcomes. Severe OIR promoted the induction of Jagged-1/Notch and curtailed DLL-4/Notch, which was an effect that could be reversed with nGSH supplementation. These findings may indicate a potential alternate pathway for ROP treatment and/or prevention.

The effects of parenteral fish oil on neurodevelopment in preterm infants: A narrative review

OBJECTIVE

This narrative review aimed to summarize studies assessing the effects of parenteral fish oil on neurodevelopment in preterm infants.

METHODS

PubMed was searched (July 1985 to October 2023). We reviewed randomized controlled trials, and observational studies assessing intravenous lipid emulsion with fish oil in preterm infants (born less than 37 weeks' gestation), that reported long-term neurodevelopmental outcomes.

RESULTS

We identified four publications relating to three randomized controlled trials in addition to four cohort studies. Study designs and outcomes were heterogenous and precluded meta-analyses. Results of trials were null for a selection of neurodevelopmental outcomes, however possible benefits of parenteral fish oil supplementation for neurodevelopment was reported in three cohort studies. Certainty of the evidence is hindered by methodological limitations of available trials and observational studies.

CONCLUSIONS

Further research is required to firmly establish the effects of parenteral fish oil on preterm neurodevelopment.

The Effects of Early Enteral and Parental Nutrition on Retinopathy of Prematurity: A Systematic Review

The management of preterm newborns must consider the severe problem of retinopathy of prematurity (ROP). A systematic review has been conducted to effectively acknowledge how enteral and parenteral early nutrition affect the growth and progression of ROP. The study summarizes recent findings from various sources to give insight into the relationship between dietary practices and ROP risks. When untreated, retinopathy of prematurity (ROP) may cause severe vision loss or blindness in premature newborns. The latter two phases of ROP progression are the most serious. A child's early nutrition, both orally and intravenously, significantly impacts the severity and progression of ROP. This systematic review aims to examine the evidence linking early nutrition to ROP in premature infants. The study used Embase, Scopus, and PubMed to conduct our search. ROP, premature newborns, and nutrition were keywords used to find relevant papers. Nine research studies made it through the screening process and offered important information on the impact of diet on ROP. These studies support the idea that poor nutrition is a driving force behind the onset of ROP. The risk of ROP has been associated with postnatal development, hyperglycemia, polyunsaturated fatty acid levels, and the presence of breast milk. The outlook for ROP has also been discovered to be affected by the length of time the patient has received parenteral feeding. The incidence and severity of ROP may be mitigated by providing better nutrition to premature newborns. This comprehensive study concludes that early nutrition, both enteral and parenteral, substantially influences the development and progression of ROP in premature newborns. The significance of nutrition in newborn care is highlighted by the possibility that improved dietary methods might aid in preventing and treating this vision-threatening illness.

Study protocol of OmegaROP-2 prospective study: expression of placental fatty acid receptors in preterm newborns with retinopathy of prematurity

BACKGROUND

Incomplete vascularization of the retina in preterm infants carries a risk of retinopathy of prematurity (ROP). Progress in neonatal resuscitation in developing countries has led to the survival of an increasing number of premature infants, resulting in an increased rate of ROP and consequently in visual disability. Strategies to reduce ROP involve optimizing oxygen saturation, nutrition, and normalizing factors such as insulin-like growth factor 1 and n-3 long-chain polyunsaturated fatty acids (LC-PUFA). Our previous study, OmegaROP, showed that there is an accumulation or retention of docosahexaenoic acid (DHA) in mothers of infants developing ROP, suggesting abnormalities in the LC-PUFA placental transfer via fatty acid transporting proteins. The present study aims to better understand the LC-PUFA transport dysfunction in the fetoplacental unit during pregnancy and to find a novel target for the prevention of ROP development.

METHODS

The study protocol is designed to evaluate the correlation between the expression level of placental fatty acid receptors and ROP occurrence. This ongoing study will include 100 mother-infant dyads: mother-infant dyads born before 29 weeks of gestational age (GA) and mother-infant dyads with full-term pregnancies. Recruitment is planned over a period of 46 months. Maternal and cord blood samples as well as placental tissue samples will be taken following delivery. ROP screening will be performed using wide-field camera imaging according to the International Classification of ROP consensus statement.

DISCUSSION

The results of this study will have a tangible impact on public health. Indeed, if we show a correlation between the expression level of placental omega-3 receptors and the occurrence of ROP, it would be an essential step in discovering novel pathophysiological mechanisms involved in this retinopathy.

TRIAL REGISTRATION

NCT04819893.

Change to Mixed-Lipid Emulsion From Soybean Oil-Based Lipid Emulsion in Pediatric Patients

Importance

Critically ill pediatric patients often require parenteral nutrition (PN) in the intensive care unit (ICU). Literature suggests mixed lipid emulsions (LE) with soybean oil reduction strategies may improve outcomes.

Objective

To examine the association of a hospital-wide switch to a mixed-lipid formula (4-OLE) with pediatric outcomes.

Design, Setting, and Participants

Retrospective cohort study at a large US academic referral center. Pediatric patients aged 1 month to 17 years requiring parenteral nutrition from May 2016 to September 2019 were included. Data were analyzed from October 2020 to February 2023.

Exposure

In 2017, Duke University Health System fully converted to a soybean oil/MCT/olive/fish oil lipid (4-OLE) from pure soybean oil-based LE in pediatric patients. Pediatric patients before the change (Intralipid [IL] group) were compared with patients after (4-OLE group).

Main Outcomes and Measures

Clinical outcomes were compared between treatment periods via multivariable regression models. The primary outcome was hospital length of stay (LOS). Fourteen secondary outcomes included hospital mortality of any cause, 30-day or 90-day readmission, pneumonia, urinary tract infections (UTIs), total caloric delivery, and liver function tests (aspartate aminotransferase, alanine transaminase, alkaline phosphatase, and total bilirubin).

Results

A total of 684 children dependent on PN were identified (342 were critically ill), with 30% (206 children) in the preswitch (IL) period and 70% (478 children) in the postswitch (4-OLE) period; 123 were male (59.7%). In comparing IL vs 4-OLE, there was a significant difference in median (IQR) age (4.0 [1.2-13.0] vs 3.0 [0.8-9.0] years, respectively; P = .04), without difference in body mass index or baseline comorbidities except for significant differences in cancer diagnosis (26 patients in the IL group [12.6%] vs 29 patients in the 4-OLE group [6.1%]; P = .004) and chronic obstructive pulmonary disease (24 patients in the IL group [11.7%] vs 30 patients in the 4-OLE group [6.3%]; P = .02). In the all children cohort, 4-OLE was associated with shorter hospital LOS (IRR, 0.81; 95% CI, 0.05-0.78), and reduced UTI risk (OR, 0.33; 95% CI, 0.18-0.64). In the ICU cohort, 4-OLE was associated with shorter hospital LOS (IRR, 0.81; 95% CI, 0.78-0.83), and reduced UTI risk (OR, 0.23; 95% CI, 0.11-0.51). Other secondary outcomes were not significant.

Conclusions and Relevance

In this observational study of clinical outcomes among children dependent on PN, a switch to 4-OLE in a large academic hospital was associated with a significant decrease in hospital LOS in ICU and non-ICU patients. These findings suggest switching to a soy-LE sparing strategy using 4-OLE is feasible, safe, and associated with improved clinical outcomes in pediatric PN patients.

Sepsis and bronchopulmonary dysplasia as potential risk factors for parenteral nutrition-associated cholestasis in neonates: a meta-analysis of retrospective studies

INTRODUCTION

The aim of this study was to evaluate whether sepsis and bronchopulmonary dysplasia (BPD) are risk factors for parenteral nutrition-associated cholestasis (PNAC) and to provide suggestions for the prevention of PNAC in infants.

EVIDENCE ACQUISITION

Electronic databases (PubMed, EBSCO, Elsevier, Springer, Wiley, and Cochrane) were searched for studies published up to October 22, 2017. Associations between sepsis, BPD and PNAC were assessed using odds ratios (ORs) and 95% confidence intervals (CIs). Heterogeneity was assessed using the I2 statistic, and subgroup analyses were performed.

EVIDENCE SYNTHESIS

Nine studies incorporating a total of 2248 cases were included in the meta-analysis. Sepsis was significantly associated with PNAC (pooled OR=2.04; 95% CI: 1.23-2.85), but BPD was not (pooled OR=1.22; 95% CI: 0.65-1.78). In a subgroup analysis, BPD was not associated with PNAC in either the non-Asian group (pooled OR=1.38; 95% CI: 0.58-2.18) or the Asian group (pooled OR=1.05; 95% CI: 0.26-1.84).

CONCLUSIONS

Sepsis, but not BPD, was a risk factor for PNAC in this meta-analysis. Further studies are needed to confirm the findings.

Retinopathy of prematurity: A review of pathophysiology and signaling pathways

Retinopathy of prematurity (ROP) is a vasoproliferative disorder of the retina and a leading cause of visual impairment and childhood blindness worldwide. The disease is characterized by an early stage of retinal microvascular degeneration, followed by neovascularization that can lead to subsequent retinal detachment and permanent visual loss. Several factors play a key role during the different pathological stages of the disease. Oxidative and nitrosative stress and inflammatory processes are important contributors to the early stage of ROP. Nitric oxide synthase and arginase play important roles in ischemia/reperfusion-induced neurovascular degeneration. Destructive neovascularization is driven by mediators of the hypoxia-inducible factor pathway, such as vascular endothelial growth factor and metabolic factors (succinate). The extracellular matrix is involved in hypoxia-induced retinal neovascularization. Vasorepulsive molecules (semaphorin 3A) intervene preventing the revascularization of the avascular zone. This review focuses on current concepts about signaling pathways and their mediators, involved in the pathogenesis of ROP, highlighting new potentially preventive and therapeutic modalities. A better understanding of the intricate molecular mechanisms underlying the pathogenesis of ROP should allow the development of more effective and targeted therapeutic agents to reduce aberrant vasoproliferation and facilitate physiological retinal vascular development.

Outcomes in preterm infants who received a lipid emulsion with fish oil: An observational study

BACKGROUND

100% soybean oil emulsions (SO100) are associated with poor docosahexaenoic acid (DHA) and arachidonic acid (ARA) status in extremely low birth weight (ELBW) infants. A multi-oil emulsion with 15% fish oil (FO15) contains more DHA and ARA than SO100. This study compares clinical outcomes, namely growth and fatty acids, in ELBW infants who received S0100 or FO15.

METHODS

This observational study included ELBW infants born between 2014 and 2019 who received SO100 or FO15 for >7 days. Gas chromatography/mass spectrometry was used to measure erythrocyte fatty acids.

RESULTS

The mean ± SD gestational age was 27 ± 3 and 26 ± 2 weeks for SO100 (n = 43) and FO15 (n = 43), respectively (P = 0.2). DHA (-0.3 ± 0.10% per week, P = 0.026, for FO15 vs -0.2 ± 0.05% per week, P < 0.001, for SO100) and ARA (-0.8 ± 0.21% per week for FO15 vs -0.9 ± 0.17% per week for SO100; P < 0.001 for both) declined in both groups with no difference between groups (P interaction > 0.7 for both). After controlling for days to reach full feeds, the mean difference in weight z score trajectories was similar (Est = -0.08; 95% CI, -0.82 to 0.04; P = 0.2), and SO100 was associated with a nonsignificant increased odds for cholestasis (odds ratio, 3.1; 95% CI, 0.96-10.2; P = 0.059). There was no difference in other clinical comorbidities.

CONCLUSIONS

In comparison with ELBW infants who received SO100, infants who received FO15 still demonstrated a decline in DHA and ARA. Growth and other clinical outcomes were unchanged.

Patterns of lipid-injectable emulsion use in neonatal intensive care units across the United States: A multi-institution survey

BACKGROUND

Lipid-injectable emulsions (ILEs) are a necessity for neonates dependent on parenteral nutrition (PN). In this manuscript, we describe the patterns of ILE use in neonatal intensive care units (NICUs) in the United States (US).

METHODS

An electronic survey was sent to 488 NICUs across the US between December 2020 and March 2021. Survey fields included availability and utilization of various ILE in neonates.

RESULTS

The response rate was 22% (107 out of 488). Soybean oil ILE (SO-ILE) and soybean oil, medium-chain triglycerides, olive oil, fish oil ILE (SO, MCT, OO, FO-ILE) had similar availability (87% vs 86%, respectively), and SO, MCT, OO, FO-ILE was more commonly used (SO-ILE, 71% vs SO, MCT, OO, FO-ILE, 86%). Fish oil-ILE (FO-ILE) was used by 55% of centers. SO-ILE was most frequently used with PN and needs <4 weeks without cholestasis (79%). The most common reason for SO, MCT, OO, FO-ILE use was cholestasis (71%). ILE minimization was used by 28% of SO-ILE and 22% of SO, MCT, OO, FO-ILE users; 95% of these centers restrict SO, MCT, OO, FO-ILE to doses ≤2 g/kg/day. Twenty-two percent of centers started FO-ILE at direct bilirubin of >5 mg/dl.

CONCLUSION

The results of this survey reveal significant variability in ILE usage across the US. Lipid minimization with SO, MCT, OO, FO-ILE and initiation of FO-ILE for cholestasis at higher bilirubin thresholds are prevalent. Such reports are crucial for a better understanding of ILE use in the NICU and in future ILE development.

Risk factors associated with Retinopathy of Prematurity development and progression

Several studies propose that Retinopathy of Prematurity (ROP) is a multifactorial disorder implicating many prenatal and postnatal factors. The objective of our study was to determine the incidence and the risk factors that influenced ROP development and progression. We retrospectively compiled data of preterms with birth weight (BW) ≤ 1.500 g and/or gestational age (GA) < 32 weeks, or BW between 1.501 and 2.000 g and/or GA ≥ 32 weeks with oxygen supply > 72 h or unstable clinical course screened for ROP in Regional University Hospital of Málaga from 2015 to 2018. 202 infants (44.7%) developed ROP and 66 exhibited progression (32.7% of ROP infants). In the univariate analysis, many risk factors were associated with ROP. In the subsequent multivariate analysis, GA, oxygen therapy and weight at 28 days of life, mechanical ventilation duration, non-invasive ventilation, surfactant administration and late-onset sepsis were independently associated with the development. However, oxygen therapy duration, late-onset sepsis and weight at 28 days were associated with the progression. The ROP development and progression risk factors were different. Our results are important to facilitate screening, early diagnosis and ROP treatment while reducing unneeded examinations.

Decreased Levels of Erythrocyte Membrane Arachidonic and Docosahexaenoic Acids Are Associated With Retinopathy of Prematurity

Purpose

Retinopathy of prematurity (ROP) can lead to blindness. Arachidonic acid (ARA) and docosahexaenoic acid (DHA) regulate retinal inflammation and angiogenesis. The aim of this study was to investigate red blood cell membrane (RBCM) ARA and DHA in preterm infants.

Methods

This prospective observational study divided infants into groups by ROP severity and RBCM ARA and DHA means and terciles.

Results

Although the mean ± SD RBCM ARA was different between groups (no ROP, 17.9% ± 0.7%, vs. type 2 ROP, 17.4% ± 0.8%, vs. type 1 ROP, 16.7% ± 1.0%; P < 0.001), the mean RBCM DHA was similar (P = 0.161). Infants with type 1 ROP were more likely to be in the lowest ARA and DHA terciles than in the highest (ARA, 44% vs. 5.6%; DHA, 22% vs. 5.6%). ARA and DHA declined over the first month of life in all ROP groups. At week 1, ARA was lower in the type 1 and type 2 ROP groups compared with the no-ROP group (18% ± 2% and 19% ± 3% vs. 21% ± 2%, respectively; P < 0.05 for all). At week 2, DHA and ARA were lower in the type I ROP group compared with the no-ROP group (3% ± 1% vs. 4% ± 1%, P = 0.03 and 16% ± 1% vs. 19% ± 1%, respectively; P < 0.01). A RBCM ARA% ≥ 17 was associated with a 45% reduction in any ROP. As the estimated 4-week ARA% mean increased by 1%, the odds of ROP decreased by 70% (odds ratio = 0.30; 95% confidence interval, 0.1-0.7).

Conclusions

Infants with severe ROP have lower ARA and DHA levels than infants without ROP. ARA and DHA may act synergistically to protect against ROP.

SMOFlipid Impact on Growth and Neonatal Morbidities in Very Preterm Infants

The soybean oil, medium-chain triglycerides, olive oil, and fish oil lipid (SMOFlipid) is increasingly being used worldwide without definite evidence of its benefits. We examined the effect of SMOFlipid on growth velocity and neonatal morbidities in very preterm infants. Very preterm infants who received soybean-based lipid emulsion between January 2015 and 2018 were compared with those who received SMOFlipids between 2019 and January 2022 in our neonatal tertiary center. Linear regression analysis was conducted to analyze the association between type of lipid emulsion and growth velocity. Modified log-Poisson regression with generalized linear models and a robust variance estimator (Huber−White) were applied to adjust for potential confounding factors. A total of 858 infants met our inclusion criteria. Of them, 238 (27.7%) received SMOFlipid. SMOFlipid was associated with lower growth velocity between birth and 36-week corrected gestational age compared with intralipid Δ weight z-score (adjusted mean difference (aMD) −0.67; 95% CI −0.69, −0.39). Subgroup analysis indicated that mainly male infants in the SMOFlipid−LE group had a lower Δ weight z-score compared to those in the intralipid group (p < 0.001), with no difference observed in females (p = 0.82). SMOFlipid was associated with a lower rate of bronchopulmonary dysplasia (BPD) (aRR 0.61; 95% CI 0.46, 0.8) and higher rate of late-onset sepsis compared with intralipid (aRR 1.44; 95% CI 1.22−1.69). SMOFlipid was associated with lower growth velocity and BPD but higher rate of late-onset sepsis—it is a double-edged sword.

Association of fish oil containing lipid emulsions with retinopathy of prematurity: a retrospective observational study

Background

Retinopathy of prematurity (ROP) remains a leading cause of childhood blindness worldwide. This study aimed to investigate whether supplementation of n-3 polyunsaturated fatty acids (n-3 PUFAs) in parenteral nutrition may have beneficial effects on ROP in preterm infants.

Methods

A total of 89 preterm infants, admitted to Neonatal Intensive Care Unit (NICU) in Anhui Provincial Children’s Hospital from September 2017 to August 2020, were recruited in the study. Based on the medical documents, the subjects were categorised into two groups: administration of the fish oil emulsion (n=43) containing soy oil, medium-chain-triglycerides (MCT), olive oil and fish oil (6g/dL, 6g/dL, 5g/dL and 3g/dL respectively), and the soy oil emulsion (n=46) containing 10g/dL of soy oil and MCT each. At 4 weeks of hospitalization, ROP was screened and diagnosed. Fatty acids in erythrocytes were determined using gas chromatography.

Results

The averaged birth weight and gestational age were 1594±296 g and 31.9±2.3 wk, 1596±263 g and 31.6±2.3 wk respectively for preterm infants in the fish oil group and soy oil group. After 4 to 6 weeks of hospitalization, among all the preterm infants, 52 developed ROP (all stages) indicating an incidence of ROP at 58.43%. Although the incidence of ROP with any stages showed no differences between the two groups, the severe ROP incidence in the group with fish oil emulsions (2.33%) was significantly lower than that in the group with soy oil emulsions (23.91%) (P<0.05). After 14 days of nutrition support, the preterm infants administered fish oil emulsions had an increase in erythrocyte DHA content, with a reduction in ratio of arachidonic acid (AA) to DHA and an increase of n-3 index.

Conclusion

Supplementation of n-3 PUFAs through parenteral fish oil containing lipid emulsions resulted in an increase in erythrocyte DHA, and this might have beneficial effects on prevention of severe ROP in preterm infants.

Providing the Best Parenteral Nutrition before and after Surgery for NEC: Macro and Micronutrients Intakes

Necrotizing enterocolitis (NEC) is the main gastrointestinal emergency of preterm infants for whom bowel rest and parenteral nutrition (PN) is essential. Despite the improvements in neonatal care, the incidence of NEC remains high (11% in preterm newborns with a birth weight <1500 g) and up to 20−50% of cases still require surgery. In this narrative review, we report how to optimize PN in severe NEC requiring surgery. PN should begin as soon as possible in the acute phase: close fluid monitoring is advocated to maintain volemia, however fluid overload and electrolytes abnormalities should be prevented. Macronutrients intake (protein, glucose, and lipids) should be adequately guaranteed and is essential in each phase of the disease. Composite lipid emulsion should be the first choice to reduce the risk of parenteral nutrition associated liver disease (PNALD). Vitamin and trace elements deficiency or overload are frequent in long-term PN, therefore careful monitoring should be planned starting from the recovery phase to adjust their parenteral intake. Neonatologists must be aware of the role of nutrition especially in patients requiring long-term PN to sustain growth, limiting possible adverse effects and long-term deficiencies.

The Role of Dietary Fats in the Development and Prevention of Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is a significant cause of mortality and morbidity in preterm infants. The pathogenesis of NEC is not completely understood; however, intestinal immaturity and excessive immunoreactivity of intestinal mucosa to intraluminal microbes and nutrients appear to have critical roles. Dietary fats are not only the main source of energy for preterm infants, but also exert potent effects on intestinal development, intestinal microbial colonization, immune function, and inflammatory response. Preterm infants have a relatively low capacity to digest and absorb triglyceride fat. Fat may thereby accumulate in the ileum and contribute to the development of NEC by inducing oxidative stress and inflammation. Some fat components, such as long-chain polyunsaturated fatty acids (LC-PUFAs), also exert immunomodulatory roles during the early postnatal period when the immune system is rapidly developing. LC-PUFAs may have the ability to modulate the inflammatory process of NEC, particularly when the balance between n3 and n6 LC-PUFAs derivatives is maintained. Supplementation with n3 LC-PUFAs alone may have limited effect on NEC prevention. In this review, we describe how various fatty acids play different roles in the pathogenesis of NEC in preterm infants.

Assessment and management of retinopathy of prematurity in the era of anti-vascular endothelial growth factor (VEGF)

The incidence of retinopathy of prematurity (ROP) continues to rise due to the improved survival of very low birth weight infants in developed countries. This epidemic is also fueled by increased survival of preterm babies with variable use of oxygen and a lack of ROP awareness and screening services in resource-limited regions. Improvements in technology and a basic understanding of the disease pathophysiology have changed the way we screen and manage ROP, educate providers and patients, and improve ROP awareness. Advancements in imaging techniques, expansion of telemedicine services, and the potential for artificial intelligence-assisted ROP screening programs have created opportunities to improve ROP care in areas with a shortage of ophthalmologists trained in ROP. To address the gap in provider knowledge regarding ROP, the Global Education Network for Retinopathy of Prematurity (GEN-ROP) created a web-based tele-education training module that can be used to educate all providers involved in ROP, including non-physician ROP screeners. Over the past 50 years, the treatment of severe ROP has evolved from limited treatment modalities to cryotherapy and laser photocoagulation. More recently, there has been growing evidence to support the use of anti-vascular endothelial growth factor (VEGF) agents for the treatment of severe ROP. However, VEGF is known to be important in organogenesis and microvascular maintenance, and given that intravitreal anti-VEGF treatment can result in systemic VEGF suppression over a period of at least 1-12 weeks, there are concerns regarding adverse effects and long-term ocular and systemic developmental consequences of anti-VEGF therapy. Future research in ophthalmology to address the growing burden of ROP should focus on cost-effective fundus imaging devices, implementation of artificial intelligence platforms, updated treatment algorithms with optimal use of anti-VEGF and careful investigation of its long-term effects, and surgical options in advanced ROP. Addressing these unmet needs will aid the global effort against the ROP epidemic and optimize our understanding and treatment of this blinding disease.

Metabolism in Retinopathy of Prematurity

Retinopathy of prematurity is defined as retinal abnormalities that occur during development as a consequence of disturbed oxygen conditions and nutrient supply after preterm birth. Both neuronal maturation and retinal vascularization are impaired, leading to the compensatory but uncontrolled retinal neovessel growth. Current therapeutic interventions target the hypoxia-induced neovessels but negatively impact retinal neurons and normal vessels. Emerging evidence suggests that metabolic disturbance is a significant and underexplored risk factor in the disease pathogenesis. Hyperglycemia and dyslipidemia correlate with the retinal neurovascular dysfunction in infants born prematurely. Nutritional and hormonal supplementation relieve metabolic stress and improve retinal maturation. Here we focus on the mechanisms through which metabolism is involved in preterm-birth-related retinal disorder from clinical and experimental investigations. We will review and discuss potential therapeutic targets through the restoration of metabolic responses to prevent disease development and progression.

[Research advances in the effect of long-chain polyunsaturated fatty acids on neonates]

Adequate supply of long-chain polyunsaturated fatty acids (LCPUFAs) is of great importance for neonates, especially preterm infants. In particular, n-3 LCPUFAs and n-6 LCPUFAs play a key role in brain development, immune regulation, and disease prevention. Lack of LCPUFAs may lead to neurodevelopmental impairment, affect the development of neonatal immune system, and result in neonatal diseases. This article reviews related research advances in the physiological function of LCPUFAs and its effect on neonates, so as to provide reference for clinical application.

Use of Lipids in Neonates Requiring Parenteral Nutrition

Neonates have limited antioxidative capacity and are at increased risk of infection and inflammation-a situation that is exacerbated in preterm neonates. Together, oxidative stress and inflammation are implicated in many serious conditions affecting neonates, such as bronchopulmonary dysplasia and periventricular leukomalacia. Neonates requiring parenteral nutrition have certain nutritional requirements. For example, very long-chain ω-3 polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are regarded as conditionally essential with critical roles during early retinal and brain development, and may also have other benefits such as anti-inflammatory effects. Because of these factors, the choice of lipid emulsion used as part of parenteral nutrition support may influence clinical outcomes in neonates. There are concerns that lipid emulsions based purely on soybean oil may increase lipid peroxidation, oxidative stress, and inflammation because of their high ω-6 PUFA and low ω-3 PUFA concentrations. Composite fish-oil containing lipid emulsions may provide advantages for neonates owing to their high DHA and EPA content and high antioxidant (α-tocopherol) levels. Here, we discuss clinical trials of lipid emulsions in preterm and term neonatal populations, with a particular emphasis on markers of oxidative stress and DHA and EPA levels. Olive oil/soybean oil lipid emulsions have shown few advantages in neonates over other lipid emulsions. However, compared with either pure soybean or soybean/olive-oil based emulsions, composite fish-oil containing lipid emulsions reduce oxidative stress/lipid peroxidation and also increase DHA and EPA levels. These advantages may translate into clinical benefits for neonates requiring parenteral nutrition.

Summary of Proceedings and Expert Consensus Statements From the International Summit "Lipids in Parenteral Nutrition"

BACKGROUND

The 2018 Lipids in Parenteral Nutrition summit involved a panel of experts in clinical nutrition, lipid metabolism, and pharmacology, to assess the current state of knowledge and develop expert consensus statements regarding the use of intravenous lipid emulsions in various patient populations and clinical settings. The main purpose of the consensus statements is to assist healthcare professionals by providing practical guidance on common clinical questions related to the provision of lipid emulsions as part of parenteral nutrition (PN).

METHODS

The summit was designed to allow interactive discussion and consensus development. The resulting consensus statements represent the collective opinion of the members of the expert panel, which was informed and supported by scientific evidence and clinical experience.

RESULTS

The current article summarizes the key discussion topics from the summit and provides a set of consensus statements designed to complement existing evidence-based guidelines. Lipid emulsions are a major component of PN, serving as a condensed source of energy and essential fatty acids. In addition, lipids modulate a variety of biologic functions, including inflammatory and immune responses, coagulation, and cell signaling. A growing body of evidence suggests that lipid emulsions containing ω-3 fatty acids from fish oil confer important clinical benefits via suppression of inflammatory mediators and activation of pathways involved in the resolution of inflammation.

CONCLUSIONS

This article provides a set of expert consensus statements to complement formal PN guideline recommendations.

Impact of Parenteral Lipid Emulsion Components on Cholestatic Liver Disease in Neonates

Total parenteral nutrition (TPN) is a life-saving intervention for infants that are unable to feed by mouth. Infants that remain on TPN for extended periods of time are at risk for the development of liver injury in the form of parenteral nutrition associated cholestasis (PNAC). Current research suggests the lipid component of TPN is a factor in the development of PNAC. Most notably, the fatty acid composition, vitamin E concentration, and presence of phytosterols are believed key mediators of lipid emulsion driven PNAC development. New emulsions comprised of fish oil and medium chain triglycerides show promise for reducing the incidence of PNAC in infants. In this review we will cover the current clinical studies on the benefit of fish oil and medium chain triglyceride containing lipid emulsions on the development of PNAC, the current constituents of lipid emulsions that may modulate the prevalence of PNAC, and potential new supplements to TPN to further reduce the incidence of PNAC.

Strategies to Prevent Severe Retinopathy of Prematurity: A 2020 Update and Meta-analysis

The incidence of retinopathy of prematurity (ROP) is showing an increasing trend in the United States. This may be because of increasing survival rates among extremely preterm infants (<25 weeks' gestation) and targeting higher oxygen saturation. Five randomized clinical trials of low versus high oxygen saturation target ranges found increased mortality in the low oxygen saturation target group and an increased incidence of ROP in the high oxygen saturation target group. The American Academy of Pediatrics recommends using an oxygen saturation target range of 90% to 95% in extremely low-birthweight infants. The change of practice to target this higher oxygen saturation range, from admission until discharge, may be contributing to the increasing incidence of ROP in extremely preterm infants. To decrease the incidence of ROP without increasing mortality, 2 new cohort trials suggest gradually increasing oxygen saturation targets as preterm infants mature. There is evidence that human milk, vitamin A, and omega-3 fatty acids can help, in addition to continuous oxygen saturation monitoring, to decrease the risk of ROP. We review this literature and provide a meta-analysis to evaluate the evidence.

Intravenous Lipid Emulsions in the NICU

The clinical goals of intravenous lipid emulsions (ILEs) have changed since their initial development. In the past, 100% soybean oil was used to provide energy and prevent an essential fatty acid deficiency. Now, different oil sources are used with the goal of improving nutritional status and preventing common neonatal comorbidities. We now have a better understanding of specific ILE constituents, namely, fatty acids, vitamin E, and phytosterols, and how these components contribute to complications such as intestinal failure-associated liver disease. This review addresses the development and composition of different ILEs and summarizes how individual ILE ingredients affect infant metabolism and health.

Parenteral Fish-Oil Lipid Emulsions in Retinopathy of Prematurity: A Retrospective Comparative Study

Purpose

To evaluate the effects of a fish oil-containing regimen on the severity of retinopathy of prematurity (ROP) in preterm infants.

Methods

In this retrospective, observational study, 82 preterm infants with documented retinal examinations were evaluated. Patients' demographic data, associated morbidities, the worst ROP zone, stage, and the presence of plus disease during the follow-up examinations, and the need for ROP treatment in the two groups were recorded and analyzed.

Results

Forty-three infants were treated with INTRAlipid®, and 39 infants were treated with 20% SMOFlipid. There were no differences in gestational age, birth weight, and associated morbidities between the two groups. No differences were observed among the two groups in their need for treatment (P = 0.51), ROP zones (P = 0.62), and plus disease (P = 0.38). Although no difference was seen in ROP stages between the groups (P = 0.41), in subgroup analysis, Stage 3 (severe ROP) occurred significantly lower in the SMOFlipid group (P = 0.04) and Stage 0 occurred significantly higher in the SMOFlipid-treated infants (P = 0.05).

Conclusions

This study showed no difference between the two groups regarding the need for the treatment. The lower prevalence of severe ROP in preterm infants receiving SMOFlipid emulsion was observed comparing to the INTRAlipid-treated infants.

Current evidence and outcomes for retinopathy of prematurity prevention: insight into novel maternal and placental contributions

Retinopathy of prematurity (ROP) is a blinding morbidity of preterm infants, which represents a significant clinical problem, accounting for up to 40% of all childhood blindness. ROP displays a range of severity, though even mild disease may result in life-long visual impairment. This is complicated by the fact that our current treatments have significant ocular and potentially systemic effects. Therefore, disease prevention is desperately needed to mitigate the life-long deleterious effects of ROP for preterm infants. Although ROP demonstrates a delayed onset of retinal disease following preterm birth, representing a potential window for prevention, we have been unable to sufficiently alter the natural disease course and meaningfully prevent ROP. Prevention therapeutics requires knowledge of early ROP molecular changes and risk, occurring prior to clinical retinal disease. While we still have an incomplete understanding of these disease mechanisms, emerging data integrating contributions of maternal/placental pathobiology with ROP are poised to inform novel approaches to prevention. Herein, we review the molecular basis for current prevention strategies and the clinical outcomes of these interventions. We also discuss how insights into early ROP pathophysiology may be gained by a better understanding of maternal and placental factors playing a role in preterm birth.

The evolving use of intravenous lipid emulsions in the neonatal intensive care unit

Parenteral nutrition and intravenous lipid emulsions are essential for promoting optimal nutrition in the neonatal intensive care unit. However, long-term use of a pure soybean lipid emulsion is associated with a liver disease known as intestinal failure associated liver disease. Over the past several years, the science of lipid emulsions has evolved with a focus on nutritional optimization and disease prevention. This review's purpose is to provide a general overview of the three main components of lipid emulsions, phytosterols, the antioxidant Vitamin E, and polyunsaturated fatty acids, and their contribution to health.

Multi-component lipid emulsion vs soy-based lipid emulsion for very low birth weight preterm neonates: A pre-post comparative study

OBJECTIVE

To examine the effectiveness of soybean oil-medium chain triglycerides-olive oil-fish oil lipid emulsion (SMOF-LE) on clinical outcomes of very-low-birth-weight neonates.

STUDY DESIGN

We conducted a pre-post comparative study of very-low-birth-weight neonates, dividing them according to lipid emulsion received: Intralipid (soy-based; n = 680) or SMOF-LE (n = 617). Primary outcomes were mortality, chronic lung disease, severe retinopathy, infection, and necrotising enterocolitis. Secondary outcomes were cholestasis, osteopenia, time to full feeds, and time to regain birthweight.

RESULTS

Baseline characteristics between groups were comparable. Primary outcomes did not differ significantly between groups, although any retinopathy was significantly lower in the SMOF-LE group. SMOF-LE group had lower odds of cholestasis, osteopenia, and lipid interruption, and reduced times to full feeds and to regain birthweight.

CONCLUSIONS

Compared with Intralipid, SMOF-LE was not associated with differences in mortality and major morbidities but was associated with lower odds of any retinopathy, cholestasis, and osteopenia; and improved lipid tolerance.

Lipid emulsions for parenterally fed term and late preterm infants

BACKGROUND

Lipid emulsions (LE) form a vital component of infant nutrition for critically ill, late preterm or term infants, particularly for those with gastrointestinal failure. Conventionally used soybean oil-based LE (S-LE) have high polyunsaturated fatty acid (PUFA) content and phytosterols, which may contribute to adverse effects including parenteral nutrition-associated liver disease (PNALD).

OBJECTIVES

To compare the safety and efficacy of all LE for parenteral nutrition (PN) in term and late preterm infants (between 34 weeks' gestation and 36 weeks' and six days' gestation) with or without surgical conditions or PNALD within first six months of life, using all possible direct comparisons.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 5), MEDLINE (1946 to 18 June 2018), Embase (1974 to 18 June 2018), CINAHL (1982 to 18 June 2018), MIDRIS (1971 to 31 May 2018), conference proceedings, trial registries (ClinicalTrials.gov and the WHO's Trials Registry), and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Randomised or quasi-randomised controlled studies in term and late preterm infants, with or without surgical conditions or PNALD.

DATA COLLECTION AND ANALYSIS

Data collection and analysis conformed to the methods of Cochrane Neonatal. We used the GRADE approach to assess the quality of evidence for important outcomes in addition to reporting the conventional statistical significance of results.

MAIN RESULTS

The review included nine randomised studies (n = 273). LE were classified in three broad groups: 1. all fish oil-containing LE including pure fish oil (F-LE) and multisource LE (e.g. medium-chain triglycerides (MCT)-olive-fish-soybean oil-LE (MOFS-LE), MCT-fish-soy oil-LE (MFS-LE) and olive-fish-soy-LE (OFS-LE)); 2. conventional pure S-LE; 3. alternative-LE (e.g. MCT-soy-LE (MS-LE), olive-soy-LE (OS-LE) and borage oil-based LE).We considered four broad comparisons: 1. all fish oil LE versus non-fish oil LE (6 studies; n = 182); 2. fish oil LE versus another fish oil LE (0 studies); 3. alternative-LE versus S-LE (3 studies; n = 91); 4. alternative-LE versus another alternative-LE (0 studies) in term and late preterm infants (0 studies), term and late preterm infants with surgical conditions (7 studies; n = 233) and term and late preterm infants with PNALD/cholestasis (2 studies; n = 40).PNALD/cholestasis was defined as conjugated bilirubin (Cbil) 2 mg/dL or greater and resolution of PNALD/cholestasis as Cbil less than 2 mg/dL. We put no restriction on timing of PNALD detection. There was heterogeneity in definitions and time points for detecting PNALD in the included studies.We found one study each in surgical infants and in infants with cholestasis, showing no evidence of difference in incidence or resolution of PNALD/cholestasis (Cbil cut-off: 2 mg/dL) with use of fish oil-containing LE compared to S-LE.We considered an outcome allowing for any definition of PNALD (different Cbil cut-off levels). In infants with surgical conditions and no pre-existing PNALD, meta-analysis showed no difference in the incidence of PNALD/cholestasis (any definition) with use of fish oil-containing LE compared to S-LE (typical risk ratio (RR) 1.20, 95% confidence interval (CI) 0.38 to 3.76; typical risk difference (RD) 0.03, 95% CI -0.14 to 0.20; 2 studies; n = 68; low-quality evidence). In infants with PNALD/cholestasis (any definition), use of fish oil-LEs was associated with significantly less cholestasis compared to the S-LE group (typical risk ratio (RR) 0.54, 95% confidence interval (CI) 0.32 to 0.91; typical risk difference (RD) -0.39, 95% CI -0.65 to -0.12; number needed to treat for additional beneficial outcome (NNTB) 3, 95% CI 2 to 9; 2 studies; n = 40; very low-quality evidence). This outcome had very low number of participants from two small studies with differences in study methodology and early termination in one study, which increased uncertainty about the effect estimates.One study in infants with cholestasis reported significantly better weight gain with a pure fish oil LE compared to a 10% S-LE (45 g/week, 95% CI 15.0 to 75.0; n = 16; very low-quality evidence). There were no significant differences in growth parameters in studies with surgical populations.For the secondary outcomes, in infants with cholestasis, one study (n = 24) reported significantly lower conjugated bilirubin levels but higher gamma glutamyl transferase levels with MOFS-LE (SMOFlipid) versus S-LE (Intralipid) and another study (n = 16), which was terminated early, reported significantly higher rates of rise in alanine aminotransferase (ALT) and conjugated bilirubin levels in the S-LE group compared to pure F-LE (Omegaven).In surgical infants, two studies each reported on hypertriglyceridaemia and Cbil levels with one study in each outcome showing significant benefit with use of a F-LE and the other study showing no difference between the groups. Meta-analysis was not performed for either of these outcomes as there were only two studies showing conflicting results with high heterogeneity between the studies.There was no evidence of differences in death, sepsis, alkaline phosphatase and ALT levels in infants with surgical conditions or cholestasis (very low-quality evidence).One study reported neurodevelopmental outcomes at six and 24 months in infants with surgical conditions (n = 11) with no evidence of difference with use of pure F-LE versus S-LE. Another study in infants with cholestasis (n = 16) reported no difference in head growth velocity between pure F-LE versus S-LE.GRADE quality of evidence ranged from low to very low as the included studies were small single-centre studies. Three of the six studies that contributed data to the review were terminated early for various reasons.

AUTHORS' CONCLUSIONS

Based on the current review, there is insufficient data from randomised studies to determine with any certainty, the potential benefit of any LE including fish oil-containing LEs over another LE, for prevention or resolution of PNALD/cholestasis or any other outcomes in term and late preterm infants with underlying surgical conditions or cholestasis. There were no studies in infants without surgical conditions or cholestasis.Further research is required to establish role of fish oil or lipids from other sources in LEs to improve PNALD/cholestasis, and other clinical outcomes in parenterally fed term and late preterm infants.

Lipid emulsions for parenterally fed preterm infants

BACKGROUND

Conventionally used soybean oil-based lipid emulsion (S-LE) have high polyunsaturated fatty acid (PUFA) content and phytosterols that may contribute to adverse effects in preterm infants. The newer lipid emulsions (LE) from different lipid sources are currently available for use in preterm infants.

OBJECTIVES

To compare the safety and efficacy of all LE for parenteral nutrition (PN) in preterm infants (less than 37 weeks' gestation) including preterm infants with surgical conditions or parenteral nutrition-associated liver disease (PNALD)/cholestasis using direct comparisons and pair-wise meta-analyses.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 5), MEDLINE (1946 to 18 June 2018), Embase (1974 to 18 July 2018), CINAHL (1982 to 18 June 2018), MIDRIS (1971 to 31 May 2018), conference proceedings, trial registries (ClinicalTrials.gov and WHO's Trials Registry and Platform), and reference lists of retrieved articles.

SELECTION CRITERIA

Randomised or quasi-randomised controlled studies in preterm infants with or without surgical conditions or PNALD within the first six months of life.

DATA COLLECTION AND ANALYSIS

Data collection and analysis conformed to the methods of Cochrane Neonatal. We used the GRADE approach to assess the quality of evidence for important outcomes in addition to reporting statistical significance of results.

MAIN RESULTS

We included 29 studies (n = 2037) in this review. LE were classified in three broad groups: 1. all fish oil-containing LE including pure fish oil-LE (F-LE) and multisource LE (e.g. medium-chain triglycerides (MCT)-olive-fish-soybean oil-LE (MOFS-LE), MCT-fish-soybean oil-LE (MFS-LE) and olive-fish-soybean oil-LE (OFS-LE); 2. conventional S-LE; 3. alternative-LE (e.g. MCT-soybean oil-LE (MS-LE), olive-soybean oil-LE and borage oil-based LE).We considered the following broad comparisons: fish oil LE versus non-fish oil LE; fish oil LE versus another fish oil LE; alternative-LE versus S-LE; alternative-LE versus another alternative-LE in preterm infants less than 37 weeks' gestation, preterm infants with surgical conditions and preterm infants with PNALD/cholestasis. Separate subgroup comparisons of each LE preparation were included within these broader groups.Most studies in preterm infants used PN for mean duration of four weeks or less and for longer duration in infants with cholestasis or surgical conditions.We defined the primary outcome of PNALD/cholestasis as conjugated bilirubin (Cbil) 2 mg/dL or greater and resolution of PNALD/cholestasis as Cbil less than 2 mg/dL. There was heterogeneity in definitions used by the included studies with Cbil cut-offs ranging from 17.1 μmol/L (1 mg/dL) up to 50 μmol/L (about 3 mg/dL).In preterm infants, meta-analysis found no evidence of a difference in the incidence of PNALD/cholestasis (Cbil cut-off: 2 mg/dl) between fish oil-LEs and all non-fish oil LEs (typical risk ratio (RR) 0.61, 95% confidence interval (CI) 0.24 to 1.56; typical risk difference (RD) -0.03, 95% CI -0.08 to 0.02; 4 studies; n = 328; low-quality evidence).We also considered an outcome allowing for any definition of PNALD (different Cbil cutoffs). In the meta-analysis for PNALD/cholestasis, using any definition and restricted to low or unclear risk of bias studies, there was no evidence of a difference between fish oil LE and all non-fish oil LE for incidence of cholestasis (typical RR 0.80, 95% CI 0.53 to 1.21; typical RD -0.02, 95% CI -0.05 to 0.02; 10 studies; n = 1024; low-quality evidence). There was no evidence of difference in subgroup meta-analyses of individual LE types in any comparison.In preterm infants with surgical conditions or cholestasis, there was only one small study each reporting no evidence of a difference in incidence or resolution of cholestasis respectively with use of a pure F-LE versus S-LE (using a Cbil cut-off of 2 mg/dL).In preterm infants with PNALD/cholestasis (using any definition), the meta-analysis showed significantly less cholestasis with the use of fish oil-LE compared to S-LE (typical RR 0.54, 95% CI 0.32 to 0.91; typical RD -0.39, 95% CI -0.65 to -0.12; number needed to treat for an additional beneficial outcome (NNTB) 3, 95% CI 2 to 9; 2 studies; n = 40; very low-quality evidence). However, this outcome had a very low number of participants from two small studies with methodological differences, one of which was terminated early, increasing the uncertainty about effect estimates.There were no differences between LE types in pair-wise meta-analyses for growth in preterm infants. There was paucity of studies in preterm infants with surgical conditions or cholestasis to perform meta-analyses for growth and most other outcomes.In the secondary outcomes for preterm infants, there was no difference between fish-oil LE and non-fish oil LE in meta-analysis for severe retinopathy of prematurity (ROP) (stage 3 or greater, or requiring surgery: typical RR 0.80, 95% CI 0.55 to 1.16; typical RD -0.03, 95% CI -0.07 to 0.02; 7 studies; n = 731; very low-quality evidence). There were no differences in the LE types in pair-wise meta-analyses for death, bronchopulmonary dysplasia (BPD), ventilation duration, patent ductus arteriosus, sepsis, necrotising enterocolitis, intraventricular haemorrhage, periventricular leukomalacia, jaundice, hyperglycaemia, hypertriglyceridaemia, intrahepatocellular lipid content and conjugated bilirubin levels in any comparison.In surgical infants, one study (n = 19) reported no differences in death, sepsis rates, Cbil and neurodevelopmental outcomes with pure F-LE versus S-LE.In infants with cholestasis, there were no evidence of differences in death or sepsis in meta-analyses between fish oil-LE and S-LE; (2 studies; n = 40; very low-quality evidence).

AUTHORS' CONCLUSIONS

In the current review, we did not find any particular LE with or without fish oil to be better than another LE in preterm infants for prevention of PNALD/cholestasis, growth, mortality, ROP, BPD and other neonatal outcomes.In preterm infants with surgical conditions or cholestasis, there is currently insufficient evidence from randomised studies to determine with any certainty if fish oil LEs offer advantage in prevention or resolution of cholestasis or in any other clinical outcome.Further research, with larger well-designed trials, is warranted to evaluate the ideal composition of LE in preterm infants and the role of fish oil-containing and other LEs in the prevention and resolution of PNALD, ROP and other clinical outcomes.

Enteral Docosahexaenoic Acid and Retinopathy of Prematurity: A Randomized Clinical Trial

BACKGROUND

Retinopathy of prematurity (ROP) is a disorder of the retina of low-birth-weight preterm infants that potentially leads to blindness. Docosahexaenoic acid (DHA), is protective in experimental models, but its administration as part of parenteral nutrition has shown inconsistent results. We test the effect of enteral DHA to prevent ROP and/or severity and to reduce hospital stay.

METHODS

This was a double-blind parallel clinical trial. Preterm infants (n = 110; 55 per group) with birth weight <1500 g but ≥1000 g were recruited in a neonatal intensive care unit. Infants were randomized to receive 75 mg of DHA/kg/d (DHA group) or high oleic sunflower oil (control group) for 14 days by enteral feeding. The effect of DHA was evaluated on any stage of ROP, severe ROP (stage ≥3) incidence, and hospital stay. Groups were compared with relative risk (RR) and 95% confidence interval (CI), Fisher's exact test, Student's t-test, or Mann-Whitney U-test, as appropriate. Logistic regression was applied to adjust for confounders.

RESULTS

There was no difference between the DHA and control groups in ROP risk (RR for DHA = 0.79; 95% CI, 0.49-1.27; P = 0.33). However, patients who received DHA showed lower risk for stage 3 ROP (RR for DHA = 0.66; 95% CI, 0.44-0.99; P = 0.03). After adjusting for confounders, this decreased risk remained significant (adjusted odds ratio = 0.10; 95% CI, 0.011-0.886; P = 0.04). Hospital stay was similar between groups.

CONCLUSION

Enteral DHA may reduce the incidence of stage 3 ROP.

Lipid emulsions for parenterally fed preterm infants

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

The primary objective is to compare the effectiveness and safety of lipid formulations from different sources, including soybean oil‐based, multicomponent, olive oil‐based, and fish oil–based, in parenterally fed preterm infants.

The secondary objective is to determine the effectiveness and safety of alternative lipid emulsions compared with soybean oil‐based lipid emulsions in relation to gestational age (less than 30 weeks' gestation; 30 weeks' gestation or more), birth weight (1000 grams or less; more than 1000 grams), clinical condition (surgical patients, patients with established cholestasis).

The progress of prophylactic treatment in retinopathy of prematurity

Retinopathy of prematurity (ROP) is a retinal vascular disorder frequently found in premature infants. Different therapeutic strategies have been developed to treat ROP. However, there are still many children with ROP suffering by severe limitations in vision or even blindness. Recently, ROP has been suggested to be caused by abnormal development of the retinal vasculature, but not simply resulted by retinal neovascularization which takes about 4 to 6wk after birth in premature infants. Thus, instead of focusing on how to reduce retinal neovascularization, understanding the pathological changes and mechanisms that occur prior to retinal neovascularization is meaningful, which may lead to identify novel target(s) for the development of novel strategy to promote the healthy growth of retinal blood vessels rather than passively waiting for the appearance of retinal neovascularization and removing it by force. In this review, we discussed recent studies about, 1) the pathogenesis prior to retinal neovascularization in oxygen-induced retinopathy (OIR; a ROP in animal model) and in premature infants with ROP; 2) the preclinical and clinical research on preventive treatment of early OIR and ROP. We will not only highlight the importance of the mechanisms and signalling pathways in regulating early stage of ROP but also will provide guidance for actively exploring novel mechanisms and discovering novel treatments for early phase OIR and ROP prior to retinal neovascularization in the future.

Retinopathy of prematurity: a review of risk factors and their clinical significance

Retinopathy of prematurity (ROP) is a retinal vasoproliferative disease that affects premature infants. Despite improvements in neonatal care and management guidelines, ROP remains a leading cause of childhood blindness worldwide. Current screening guidelines are primarily based on two risk factors: birth weight and gestational age; however, many investigators have suggested other risk factors, including maternal factors, prenatal and perinatal factors, demographics, medical interventions, comorbidities of prematurity, nutrition, and genetic factors. We review the existing literature addressing various possible ROP risk factors. Although there have been contradictory reports, and the risk may vary between different populations, understanding ROP risk factors is essential to develop predictive models, to gain insights into pathophysiology of retinal vascular diseases and diseases of prematurity, and to determine future directions in management of and research in ROP.

A Mixed Lipid Emulsion for Prevention of Parenteral Nutrition Associated Cholestasis in Extremely Low Birth Weight Infants: A Randomized Clinical Trial

OBJECTIVES

To examine whether a mixed lipid emulsion reduces the incidence of parenteral nutrition associated cholestasis (PNAC) in extremely low birth weight (ELBW, <1000 g) infants.

STUDY DESIGN

This double-blind randomized trial of 230 ELBW infants (June 2012-October 2015) was performed at a single level IV neonatal intensive care unit. Patients received either a mixed lipid emulsion composed of soybean oil, medium chain triglycerides, olive oil, and fish oil-(intervention) or a soybean oil-based lipid emulsion (control) for parenteral nutrition. The primary outcome measure was PNAC (conjugated bilirubin >1.5 mg/dL [25 µmol/L] at 2 consecutive measurements). The study was powered to detect a reduction of PNAC from 25% to 10%.

RESULTS

Reasons for noneligibility of 274 infants screened were refusal to participate (n = 16), death (n = 10), withdrawal of treatment (n = 5), higher order multiples (n = 9), and parents not available for consent (n = 4). Intention to treat analysis was carried out in 223 infants (7 infants excluded after randomization). Parenteral nutrition associated cholestasis was 11 of 110 (10.1%) in the intervention and 18 of 113 (15.9%) in the control group (P = .20). Multivariable analyses showed no statistically significant difference in the intention to treat (aOR 0.428, 95% CI 0.155-1.187; P = .10) or per protocol population (aOR 0.457, 95% CI 0.155-1.347; P = .16). There was no statistically significant effect on any other neonatal morbidity.

CONCLUSIONS

The incidence of parenteral nutrition associated cholestasis was not significantly reduced using a mixed lipid emulsion in ELBW infants.

TRIAL REGISTRATION

ClinicalTrials.govNCT01585935.

Recent advances in our understanding of the mechanisms of late lung development and bronchopulmonary dysplasia

The objective of lung development is to generate an organ of gas exchange that provides both a thin gas diffusion barrier and a large gas diffusion surface area, which concomitantly generates a steep gas diffusion concentration gradient. As such, the lung is perfectly structured to undertake the function of gas exchange: a large number of small alveoli provide extensive surface area within the limited volume of the lung, and a delicate alveolo-capillary barrier brings circulating blood into close proximity to the inspired air. Efficient movement of inspired air and circulating blood through the conducting airways and conducting vessels, respectively, generates steep oxygen and carbon dioxide concentration gradients across the alveolo-capillary barrier, providing ideal conditions for effective diffusion of both gases during breathing. The development of the gas exchange apparatus of the lung occurs during the second phase of lung development-namely, late lung development-which includes the canalicular, saccular, and alveolar stages of lung development. It is during these stages of lung development that preterm-born infants are delivered, when the lung is not yet competent for effective gas exchange. These infants may develop bronchopulmonary dysplasia (BPD), a syndrome complicated by disturbances to the development of the alveoli and the pulmonary vasculature. It is the objective of this review to update the reader about recent developments that further our understanding of the mechanisms of lung alveolarization and vascularization and the pathogenesis of BPD and other neonatal lung diseases that feature lung hypoplasia.