Survey of vitamin A supplementation for extremely-low-birth-weight infants: is clinical practice consistent with the evidence?

Early postnatal high-dose fat-soluble enteral vitamin A supplementation for moderate or severe bronchopulmonary dysplasia or death in extremely low birthweight infants (NeoVitaA): a multicentre, randomised, parallel-group, double-blind, placebo-controlled, investigator-initiated phase 3 trial

BACKGROUND

Vitamin A plays a key role in lung development, but there is no consensus regarding the optimal vitamin A dose and administration route in extremely low birthweight (ELBW) infants. We aimed to assess whether early postnatal additional high-dose fat-soluble enteral vitamin A supplementation versus placebo would lower the rate of moderate or severe bronchopulmonary dysplasia or death in ELBW infants receiving recommended basic enteral vitamin A supplementation.

METHODS

This prospective, multicentre, randomised, parallel-group, double-blind, placebo-controlled, investigator-initiated phase 3 trial conducted at 29 neonatal intensive care units in Austria and Germany assessed early high-dose enteral vitamin A supplementation (5000 international units [IU]/kg per day) or placebo (peanut oil) for 28 days in ELBW infants. Eligible infants had a birthweight of more than 400 g and less than 1000 g; gestational age at birth of 32+0 weeks postmenstrual age or younger; and the need for mechanical ventilation, non-invasive respiratory support, or supplemental oxygen within the first 72 h of postnatal age after admission to the neonatal intensive care unit. Participants were randomly assigned by block randomisation with variable block sizes (two and four). All participants received basic vitamin A supplementation (1000 IU/kg per day). The composite primary endpoint was moderate or severe bronchopulmonary dysplasia or death at 36 weeks postmenstrual age, analysed in the intention-to-treat population. This trial was registered with EudraCT, 2013-001998-24.

FINDINGS

Between March 2, 2015, and Feb 27, 2022, 3066 infants were screened for eligibility at the participating centres. 915 infants were included and randomly assigned to the high-dose vitamin A group (n=449) or the control group (n=466). Mean gestational age was 26·5 weeks (SD 2·0) and mean birthweight was 765 g (162). Moderate or severe bronchopulmonary dysplasia or death occurred in 171 (38%) of 449 infants in the high-dose vitamin A group versus 178 (38%) of 466 infants in the control group (adjusted odds ratio 0·99, 95% CI 0·73-1·55). The number of participants with at least one adverse event was similar between groups (256 [57%] of 449 in the high-dose vitamin A group and 281 [60%] of 466 in the control group). Serum retinol concentrations at baseline, at the end of intervention, and at 36 weeks postmenstrual age were similar in the two groups.

INTERPRETATION

Early postnatal high-dose fat-soluble enteral vitamin A supplementation in ELBW infants was safe, but did not change the rate of moderate or severe bronchopulmonary dysplasia or death and did not substantially increase serum retinol concentrations.

FUNDING

Deutsche Forschungsgemeinschaft and European Clinical Research Infrastructures Network (ECRIN).

Moving Bronchopulmonary Dysplasia Research from the Bedside to the Bench

Although advances in the respiratory management of extremely preterm infants have led to improvements in survival, this progress has not yet extended to a reduction in the incidence of bronchopulmonary dysplasia (BPD). BPD is a complex multifactorial condition that primarily occurs due to disturbances in the regulation of normal pulmonary airspace and vascular development. Preterm birth and exposure to invasive mechanical ventilation also compromises large airway development, leading to significant morbidity and mortality. Although both predisposing and protective genetic and environmental factors have been frequently described in the clinical literature, these findings have had limited impact on the development of effective therapeutic strategies. This gap is likely because the molecular pathways that underlie these observations are yet not fully understood, limiting the ability of researchers to identify novel treatments that can preserve normal lung development and/or enhance cellular repair mechanisms. In this review article, we will outline various well-established clinical observations whilst identifying key knowledge gaps that need to be filled with carefully designed pre-clinical experiments. We will address these issues by discussing controversial topics in the pathophysiology, the pathology and the treatment of BPD, including an evaluation of existing animal models that have been used to answer important questions.

Vitamin A supplementation in very-preterm or very-low-birth-weight infants to prevent morbidity and mortality: a systematic review and meta-analysis of randomized trials

BACKGROUND

A previous systematic review showed that intramuscular vitamin A supplementation reduced the risk of bronchopulmonary dysplasia (BPD) in very-low-birth-weight (VLBW) infants. However, more recent studies have questioned this finding.

OBJECTIVES

Our objective was to synthesize current evidence on vitamin A supplementation in very-preterm (<32 wk gestational age) or VLBW infants and investigate the factors that may modify its efficacy.

METHODS

A systematic review was conducted using the Cochrane systematic review methodology. We included randomized controlled trials investigating vitamin A supplementation for reducing morbidity and mortality in very-preterm or VLBW infants. Certainty of evidence was assessed using Grading of Recommendations, Assessment, Development and Evaluation (GRADE) recommendations. Prespecified subgroup analyses assessed factors that may modify the effects of vitamin A supplementation.

RESULTS

We included 17 studies (n = 2471) in the qualitative and 15 studies (n = 2248) in the quantitative synthesis. Moderate-certainty evidence suggested a beneficial effect of vitamin A for decreasing the risk of BPD at 36 wk postmenstrual age (RR: 0.83; 95% CI: 0.74, 0.93; numbers needed to treat for an additional beneficial outcome: 16; 95% CI: 9, 53; 9 studies, n = 1752; P = 0.002). Subgroup analysis suggested that the beneficial effect was limited to infants with baseline vitamin A intake <1500 IU · kg-1 · d-1. Both enteral and parenteral routes were effective. Vitamin A supplementation did not have adverse effects and did not alter mortality before discharge (12 studies, n = 1917) or neurodevelopmental outcomes at 18-22 mo (1 study, n = 538).

CONCLUSIONS

The benefit of vitamin A supplementation for reducing BPD is likely to be limited to infants with baseline vitamin A intake <1500 IU · kg-1 · d-1 and is not affected by the route of administration.

Should Vitamin A Injections to Prevent Bronchopulmonary Dysplasia or Death Be Reserved for High-Risk Infants? Reanalysis of the National Institute of Child Health and Human Development Neonatal Research Network Randomized Trial

OBJECTIVE

To determine whether infants at higher risk of bronchopulmonary dysplasia (BPD) or death benefit more from vitamin A therapy than those at lower risk.

STUDY DESIGN

We conducted a post hoc reanalysis of a landmark phase III randomized controlled trial conducted from January 1996 to July 1997 at 14 university-affiliated neonatal intensive care units in the US. Data analysis was performed from October 2019 to October 2020. Infants born weighing 401-1000 g and receiving respiratory support at 24 hours of age were assigned to intramuscular vitamin A 5000 IU or sham procedure 3 times weekly for 4 weeks. The primary outcome was BPD, defined as use of supplemental oxygen, or death at 36 weeks postmenstrual age. An externally validated model for predicting BPD or death was used to estimate the risk of these outcomes for each infant.

RESULTS

As previously reported, 222 of 405 infants (54.8%) assigned vitamin A therapy and 248 of 402 infants (61.7%) in the control group developed BPD or died (relative risk [RR], 0.89 [95% CI, 0.80-0.99]; risk difference [RD], -6.9% [95% CI, -13.0 to -0.7]). The predicted individual risks of BPD or death ranged from 7.1% to 98.6% (median, 61.5%; mean, 60.9%). The effect of vitamin A therapy on BPD or death depended on infants' risk of the primary outcome (P = .03 for interaction): for example, a RR of 0.73 (RD, -14.5%) for infants with a 25% predicted risk and a RR of 0.96 (RD, -1.0%) for infants with a 75% risk. There was no difference in the decrease in vitamin A deficiency across risk groups.

CONCLUSIONS

Contrary to expectations, the effect of vitamin A therapy on BPD or death was greater for lower risk than higher risk infants.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01203488.

Enteral Vitamin A for Reducing Severity of Bronchopulmonary Dysplasia: A Randomized Trial

BACKGROUND AND OBJECTIVES

Evidence suggests that intramuscular vitamin A reduces the risk of bronchopulmonary dysplasia (BPD) in preterm infants. Our objective was to compare enteral water-soluble vitamin A with placebo supplementation to reduce the severity of BPD in extremely preterm infants.

METHODS

We conducted a double-blind randomized controlled trial in infants <28 weeks' gestation who were to receive either enteral water-soluble vitamin A (5000 IU per day) or a placebo. Supplementation was started within 24 hours of introduction of feeds and continued until 34 weeks' postmenstrual age (PMA). The primary outcome was the severity of BPD, assessed by using the right shift of the pulse oximeter saturation versus the inspired oxygen pressure curve.

RESULTS

A total of 188 infants were randomly assigned. The mean ± SD birth weight (852 ± 201 vs 852 ± 211 g) and gestation (25.8 ± 1.49 vs 26.0 ± 1.39 weeks) were comparable between the vitamin A and placebo groups. There was no difference in the right shift (median [25th-75th percentiles]) of the pulse oximeter saturation versus inspired oxygen pressure curve (in kilopascals) between the vitamin A (11.1 [9.5-13.7]) and placebo groups (10.7 [9.5-13.1]) (P = .73). Enteral vitamin A did not affect diagnosis of BPD or other clinical outcomes. Plasma retinol levels were significantly higher in the vitamin A group versus the placebo group on day 28 and at 34 weeks' PMA.

CONCLUSIONS

Enteral water-soluble vitamin A supplementation improves plasma retinol levels in extremely preterm infants but does not reduce the severity of BPD.

EARLY VITAMIN A SUPPLEMENTATION IMPROVES THE OUTCOME OF RETINOPATHY OF PREMATURITY IN EXTREMELY PRETERM INFANTS

PURPOSE

This study assessed the efficacy and safety of early vitamin A (VA) supplementation to improve outcomes of retinopathy of prematurity in extremely preterm infants.

METHODS

A total of 262 eligible extremely preterm infants underwent randomization; of these, 132 were assigned to the VA group and 130 to the control group. The infants were administered a solution of VA (1,500 IU/day), added to their enteral feeds as soon as minimal feeding was introduced and continued for 28 days or until discharge.

RESULTS

With no adverse effects occurring, serum VA of the VA-supplemented infants on Days 14, 28, and postmenstrual 36 weeks was higher than that of the placebo group (P < 0.001). No signs of VA toxicity or increased intracranial pressure were reported. The VA group had lower unadjusted rates of Type 1 retinopathy of prematurity (1.6 vs. 6.9%, P = 0.030) and bronchopulmonary dysplasia (18.9 vs. 33.8%, P = 0.008) than the control group. Regression analysis revealed an association between serum VA levels and risk of Type 1 retinopathy of prematurity (beta = -2.37).

CONCLUSION

Vitamin A supplementation reduced VA deficiency in extremely preterm infants; it was associated with a decreased incidence of Type 1 retinopathy of prematurity and may also have a positive impact on reducing bronchopulmonary dysplasia.

Pharmacotherapy for the Prevention of Bronchopulmonary Dysplasia: Can Anything Compete with Caffeine and Corticosteroids?

Bronchopulmonary dysplasia (BPD) is a morbidity of prematurity with implications for respiratory and neurologic health into adulthood. Multiple risk factors contribute to the development of BPD leading to examination of various prevention strategies. The roles of systemic corticosteroids and caffeine have been addressed by the American Academy of Pediatrics. The place in therapy of other agents commonly utilized in clinical practice remains unclear. Inhaled nitric oxide has been the subject of numerous large, randomized controlled trials in preterm infants. Despite sound rationale, these trials have largely failed to document benefit, suggesting a limited role for inhaled nitric oxide therapy in the preterm population. In contrast, intramuscular vitamin A has been documented to reduce the incidence of BPD in randomized trials. However, the invasiveness and the sporadic availability of this therapy have led to decreased utilization. All macrolide antibiotics do not appear to have a similar impact on the incidence of BPD; however, azithromycin administered to infants colonized with Ureaplasma may have impact. Questions remain about the optimal dosing approach and long-term safety of this intervention. Finally, diuretic therapy is widely used in clinical practice despite significant toxicities and limited data supporting a role in BPD prevention. Taken together, available data suggest that caffeine and selective use of corticosteroids remain the mainstays of pharmacologic BPD prevention.

Intramuscular Followed by Oral Vitamin A Supplementation in Neonates with Birth Weight from 750 to 1250 g: A Randomized Controlled Trial

Multiple intramuscular (IM) injections of vitamin A have been shown to decrease bronchopulmonary dysplasia in very low birth weight (VLBW) neonates. However, this regime is neither practical nor popular. Oral vitamin A has failed to achieve adequate plasma levels. We aimed to investigate if a schedule of initial IM followed by oral supplementation can reduce vitamin A deficiency. This was a blinded, randomized controlled trial, conducted in a level III neonatal unit. Neonates with birth weight from 750 to 1250 g, were enrolled at the age of 24-96 h of life. They were randomly allocated to vitamin A supplementation (VAS) (n = 61) or placebo group (n = 59). VAS group received vitamin A 5000 IU IM on alternate days till establishment of adequate enteral feeds, followed by oral 10,000 IU daily for 28 days. The primary outcome was incidence of vitamin A deficiency (plasma retinol < 200 μg/L) on day 28. A total of 120 neonates with mean (SD) gestation age and birth weight of 31 (2.4) weeks and 1065 (141) g, respectively were enrolled. More than 90% of cases were vitamin A deficient at the baseline. The proportion of vitamin A deficient infants on day 28 of study was significantly lower in VAS group compared to placebo group (4% vs. 61%, p < 0.001). The median (1st-3rd quartile) plasma retinol levels (μg/L) were significantly higher in VAS group compared to placebo [489 (295,627) vs. 184 (156,240), p < 0.001]. We conclude that the IM followed by oral VAS significantly reduced the incidence of vitamin A deficiency in VLBW infants.

Enteral vitamin A for reducing severity of bronchopulmonary dysplasia in extremely preterm infants: a randomised controlled trial

Background

Intramuscular vitamin A supplementation decreases the risk of bronchopulmonary dysplasia (BPD) in very-low-birth-weight preterm infants without significant adverse effects. However, intramuscular vitamin A supplementation is not widely accepted because of the discomfort and risk of trauma associated with repeated injections. Enteral vitamin A supplementation has not been studied adequately in the clinical trials. Enterally administered water-soluble vitamin A is absorbed better than the fat-soluble form. We hypothesised that enteral administration of a water-soluble vitamin A preparation will decrease severity of BPD compared with a control group receiving placebo.

Methods

We plan a double-blind randomised placebo-controlled trial at a tertiary neonatal-perinatal intensive care unit. Eligibility criteria include infants born at less than 28 weeks’ gestational age and less than 72 h of life. Infants with major congenital gastrointestinal or respiratory tract abnormalities will be excluded. After parental consent, infants will be randomized to receive either enteral water-soluble vitamin A (5000 IU once a day) or placebo. The intervention will be started within 24 h of introduction of feeds and continued until 34 weeks’ post-menstrual age (PMA).

The primary outcome is severity of BPD at 36 weeks’ PMA. Severity of BPD will be assessed objectively from the right-shift of the peripheral oxyhaemoglobin saturation versus partial pressure of inspired oxygen (SpO₂-PiO₂) curve. We require 188 infants for 80% power and 5% significance level based on an expected 20% decrease in the right shift of the SpO₂-PiO₂ curve in the vitamin A group (primary outcome) compared with control group at 36 weeks’ PMA, and a 20% attrition rate.

Secondary outcomes will be plasma and salivary concentrations of vitamin A on day 28 of the trial (first 30 infants), lung and diaphragm function, clinical outcomes at 36 week’ PMA or before discharge/death, and safety of vitamin A.

Discussion

BPD poses a significant economic burden on the health-care system. If our study shows that enteral supplementation of water-soluble vitamin A is safe and effective for decreasing the severity of BPD, it will provide the opportunity to further evaluate a simple, globally acceptable preventive therapy for BPD.

Trial registration

ANZCTR; ACTRN12616000408482 (30th March 2016).

Electronic supplementary material

The online version of this article (10.1186/s12887-017-0958-x) contains supplementary material, which is available to authorized users.

Lung development, regeneration and plasticity: From disease physiopathology to drug design using induced pluripotent stem cells

Lungs have a complex structure composed of different cell types that form approximately 17 million airway branches of gas-delivering bronchioles connected to 500 million gas-exchanging alveoli. Airways and alveoli are lined by epithelial cells that display a low rate of turnover at steady-state, but can regenerate the epithelium in response to injuries. Here, we review the key points of lung development, homeostasis and epithelial cell plasticity in response to injury and disease, because this knowledge is required to develop new lung disease treatments. Of note, canonical signaling pathways that are essential for proper lung development during embryogenesis are also involved in the pathophysiology of most chronic airway diseases. Moreover, the perfect control of these interconnected pathways is needed for the successful differentiation of induced pluripotent stem cells (iPSC) into lung cells. Indeed, differentiation of iPSC into airway epithelium and alveoli is based on the use of biomimetics of normal embryonic and fetal lung development. In vitro iPSC-based models of lung diseases can help us to better understand the impaired lung repair capacity and to identify new therapeutic targets and new approaches, such as lung cell therapy.

The Future of Bronchopulmonary Dysplasia: Emerging Pathophysiological Concepts and Potential New Avenues of Treatment

Yearly more than 15 million babies are born premature (<37 weeks gestational age), accounting for more than 1 in 10 births worldwide. Lung injury caused by maternal chorioamnionitis or preeclampsia, postnatal ventilation, hyperoxia, or inflammation can lead to the development of bronchopulmonary dysplasia (BPD), one of the most common adverse outcomes in these preterm neonates. BPD patients have an arrest in alveolar and microvascular development and more frequently develop asthma and early-onset emphysema as they age. Understanding how the alveoli develop, and repair, and regenerate after injury is critical for the development of therapies, as unfortunately there is still no cure for BPD. In this review, we aim to provide an overview of emerging new concepts in the understanding of perinatal lung development and injury from a molecular and cellular point of view and how this is paving the way for new therapeutic options to prevent or treat BPD, as well as a reflection on current treatment procedures.

Variations and similarities in clinical management of neonatal abstinence syndrome: Findings of a Canadian survey

Background

There are no evidence-based national guidelines for managing neonatal abstinence syndrome (NAS) and surveys from other countries have demonstrated considerable variations in practice.

Objective

To describe NAS management practices in Canada.

Method

The directors of all Level 2 and Level 3 neonatal intensive care units (NICUs) were contacted to request their participation in a structured telephone survey. Frequency distributions were generated and associations between practice variations and unit type (Level 2 or 3) and size were examined.

Results

Personnel at 65 of 103 sites (63.1%) participated. Most (92.3%) stated their hospital has a written NAS practice guideline. The majority (89.5%) use a version of Finnegan's scoring system to monitor signs. If pharmacological treatment is required, 89.2% admit infants to the NICU and 93.8% routinely use cardiorespiratory monitors when treatment is initiated. Morphine is the first-line medication at most sites (96.9%). There was greater variability in terms of other practices: 44.6% observe at-risk infants in the NICU, while 52.3% allow them to room-in with their mothers; 65.1% use adjunct medications; 36.9% and 38.9% will discharge infants on the first-line and adjunct medications respectively, and 53.8% reported that breastfeeding is always encouraged, while 44.6% discourage breastfeeding if the mother continues to use illicit drugs and 1.5% make recommendations on an individual basis. Few practice variations were associated with unit type or size.

Conclusion

While most NICUs surveyed have an NAS practice guideline, there are some notable differences in how NAS is managed. This underscores the need for research that can be translated into best practices.

Vitamin A Supplementation for the Prevention of Bronchopulmonary Dysplasia in Preterm Infants: An Update

Bronchopulmonary dysplasia (BPD) is a common complication of premature birth and is associated with significant morbidity. Vitamin A supplementation has been suggested as a potential preventative measure against BPD due to its role in lung maturation and because preterm infants are particularly predisposed to vitamin A deficiency. The aim of this review was to determine whether vitamin A supplementation reduces BPD risk among preterm infants. PubMed, CINAHL, and Web of Science databases were searched with the keywords "bronchopulmonary dysplasia," "vitamin A," and "preterm infants" and with the time frame of 2006-2016, and 4 studies were selected for review per the inclusion criteria. Only 1 study found a significant reduction in BPD risk associated with vitamin A supplementation; however, 2 studies indicated a nonsignificant benefit and may have been underpowered to show statistical significance. One study revealed an increased risk of sepsis associated with vitamin A supplementation (for infants weighing >1000 g at birth), but no risk was seen with vitamin A supplementation in the other studies. Because intramuscular vitamin A has shown benefit with minimal risk, continued supplementation for preterm infants is warranted. Future studies aimed at assessing infant groups that are most likely to benefit from supplementation (based on birth weight or other conditions), as well as determining the optimal dosing while minimizing injections, would be beneficial.

Pentoxifylline for the prevention of bronchopulmonary dysplasia in preterm infants

BACKGROUND

Bronchopulmonary dysplasia (BPD) is a common complication in preterm infants. BPD is associated with poor long-term respiratory and neurodevelopmental outcome and increased mortality. The prophylactic use of agents that modulate inflammation such as pentoxifylline, a synthetic methylxanthine and phosphodiesterase inhibitor, may reduce the incidence of BPD.

OBJECTIVES

The primary objective of this review was to determine the effect of pentoxifylline on the incidence of BPD, death prior to 36 weeks postmenstrual age (PMA), and BPD or death prior to 36 weeks PMA in preterm neonates.

SEARCH METHODS

We searched the Cochrane Neonatal Review Group Specialized Register, CENTRAL (The Cochrane Library Issue 9, 2012), EMBASE (January 1974 to September 2012), PubMed (January 1966 to September 2012), and CINAHL (January 1982 to September 2012) in September 2012. We checked references and cross-references from identified studies. We handsearched abstracts from the proceedings of the Pediatric Academic Societies Meetings (from January 1990 to September 2012). We placed no restrictions on language.

SELECTION CRITERIA

Randomised or quasi-randomised clinical trials of systemic or nebulised pentoxifylline in preterm neonates less than 32 weeks gestational age or less than 1500 g birth weight, reporting on at least one outcome of interest, were eligible for inclusion in the review.

DATA COLLECTION AND ANALYSIS

We used the standard methods of the Cochrane Neonatal Review Group and The Cochrane Collaboration. Two review authors (SMS and SK) independently searched the literature as described above and selected studies. Any disagreements were resolved by discussion involving all review authors.

MAIN RESULTS

We identified one randomised clinical trial eligible for inclusion in this review. This study compared the use of nebulised pentoxifylline versus placebo for prevention of BPD in 100 preterm infants and was at high risk of bias due to lack of blinding of intervention and outcome assessors, and incomplete outcome data. There was no statistically significant effect of nebulised pentoxifylline versus placebo on individual outcomes of BPD at 36 weeks PMA or on death prior to 36 weeks PMA. There was no significant effect of nebulised pentoxifylline on intraventricular haemorrhage, periventricular leukomalacia, sepsis, or patent ductus arteriosus (PDA) requiring ligation. The study did not report any of the other secondary outcomes considered for this review. Reporting of adverse events was very limited and did not allow for reliable judgement on the incidence of such events. No long-term outcomes were reported.

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine the safety and efficacy of pentoxifylline for prevention of BPD in preterm neonates. We encourage researchers to conduct clinical trials to confirm or refute the role of pentoxifylline for prevention of BPD in preterm neonates. These trials should report on clinically important outcomes and, ideally, on long-term neurodevelopmental outcome.

Effects of early inhaled nitric oxide therapy and vitamin A supplementation on the risk for bronchopulmonary dysplasia in premature newborns with respiratory failure

OBJECTIVE

To assess whether the combination of early inhaled nitric oxide (iNO) therapy and vitamin A supplementation lowers the incidence of bronchopulmonary dysplasia (BPD) in premature newborns with respiratory failure.

STUDY DESIGN

A total of 793 mechanically ventilated infants (birth weight 500-1250 g) were randomized (after stratification by birth weight) to receive placebo or iNO (5 ppm) for 21 days or until extubation (500-749, 750-999, or 1000-1250 g). A total of 398 newborns received iNO, and of these, 118 (30%) received vitamin A according to their enrollment center. We compared patients who received iNO + vitamin A with those who received iNO alone. The primary outcome was a composite of death or BPD at 36 weeks postconceptual age.

RESULTS

BPD was reduced in infants who received iNO + vitamin A for the 750-999 g birth weight group compared with iNO alone (P = .01). This group also showed a reduction in the combined outcome of BPD + death compared with iNO alone (P = .01). The use of vitamin A did not change the risk for BPD in the placebo group. Overall, the use of vitamin A was low (229 of 793 patients, or 29%). Combined therapy improved Bayley Scales of Infant Development II Mental and Psychomotor Developmental Index scores at 1 year compared with infants treated solely with iNO for the 500-749 g birth weight group.

CONCLUSIONS

In this retrospective analysis of the nonrandomized use of vitamin A, combined iNO + vitamin A therapy in preterm infants with birth weight 750-999 g reduced the incidence of BPD and BPD + death and improved neurocognitive outcomes at 1 year in the 500-749 g birth weight group.

Bronchopulmonary dysplasia: clinical perspective

Since Northway's original description of BPD almost 45 years ago, the clinical presentation of BPD has evolved into a disease process, which mostly involves extremely premature infants. This new form of BPD is the result of multiple antenatal and postnatal factors that can cause injury to the developing lung leading to altered alveolar and vascular development. Over the years, there has been considerable increase in knowledge of factors that contribute to the development of BPD. This has led to different strategies for prevention as well as management of BPD. Some of these strategies have been successful and have withstood the test of clinical trials, such as vitamin A supplementation, post-natal steroids, caffeine, and volume targeted ventilation. The evidence for other interventions has been weak or negative. With better understanding of the complex and multifactorial pathogenesis of BPD, it is quite clear that any single therapy is very unlikely to eliminate this problem unless it reduces prematurity. Further development in prevention and treatment of BPD will likely need a multi-pronged strategy with novel therapeutic agents acting at various stages of the disease process.

Vitamin A supplementation in extremely low-birth-weight infants: subgroup analysis in small-for-gestational-age infants

OBJECTIVE

Preterm infants with intrauterine growth restriction are at increased risk of respiratory distress syndrome and bronchopulmonary dysplasia (BPD). A randomized clinical trial by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network demonstrated that vitamin A supplementation in extremely low-birth-weight (ELBW) preterm infants requiring early respiratory support decreased the risk of developing BPD.

STUDY DESIGN

A subgroup analysis of small-for-gestational-age (SGA) infants from the original NICHD trial was performed to test the hypothesis that in infants requiring early respiratory support, vitamin A supplementation decreases the relative risk of BPD or death in premature SGA infants to a greater extent than in gestational age-equivalent vitamin A-treated appropriate-for-gestational-age (AGA) infants.

RESULTS

Although vitamin A supplementation significantly increased serum retinol concentrations in AGA ELBW infants (median [5th percentile, 95th percentile]: 16.3 [-7.0, 68.8] versus 2.4 [-13.9, 55.1]; p < 0.001), no increases were noted in SGA ELBW infants.

CONCLUSIONS

Given the limited power of this analysis due to a low number of SGA infants, these data did not provide evidence to support the hypothesis that vitamin A supplementation in preterm SGA infants requiring early respiratory support decreases the relative risk of BPD or death as compared with preterm AGA infants.

Vitamin A for preterm infants; where are we now?

In the 35 years since low plasma vitamin A levels were first described in premature infants, much effort has gone into attempting to describe the functional consequences of vitamin A deficiency in this population. Supplementation of extremely low birth weight infants with intramuscular (i.m.) vitamin A has a significant but modest beneficial effect upon the development of chronic lung disease (NNT 13), most likely due to reduced production of pro-inflammatory cytokines. Early high dose i.m. vitamin A also improves retinal development and there are limited clinical and laboratory data suggesting a role for vitamin A in prevention of retinopathy of prematurity. Despite evidence of benefit, there is reluctance to give routine i.m. vitamin A in the neonatal intensive care unit, but current intravenous supplementation is almost certainly inadequate. Further work is required to identify the optimal dose and most appropriate route of administration of vitamin A for preterm infants.

Vitamin A supplementation improves retinal function in infants at risk of retinopathy of prematurity

OBJECTIVE

Preterm infants show reduced retinal sensitivity at term corrected age compared with newborn term infants. We tested the hypothesis that retinal sensitivity in preterm infants is improved by early, high-dose vitamin A.

STUDY DESIGN

We report a double-blind, randomized controlled trial of infants <32 weeks' gestation and/or <1501 g birth weight. Supplemented infants received additional intramuscular vitamin A 10 000 IU 3 times weekly from day 2 for a minimum of 2 weeks or until establishment of oral feeding. Hepatic stores were assessed by relative dose response (RDR). The primary outcome measure was cone-corrected dark-adapted retinal rod sensitivity measured by electroretinogram at 36 weeks' postmenstrual age (PMA).

RESULTS

Eighty-nine infants (42 supplemented and 47 controls) were recruited. Plasma retinol was higher in supplemented infants at 7 and 28 days (median, 1.0 vs 0.5 μmol/L and 0.7 vs 0.6 μmol/L; P < .001 and .03, respectively). Neither plasma retinol nor RDR differed between groups at 36 weeks' PMA. Retinal sensitivity was greater in supplemented infants (-0.81 vs -0.61 log cd • s • m(-2); P < .03) and was not related to RDR.

CONCLUSIONS

Early high-dose intramuscular vitamin A supplementation for infants at risk of retinopathy of prematurity improves retinal function at 36 weeks' PMA.

Understanding variation in vitamin A supplementation among NICUs

OBJECTIVE

We examined and characterized variation among NICUs in the use of vitamin A supplementation for the prevention of bronchopulmonary dysplasia in extremely low birth weight infants.

METHODS

An historical cohort study of extremely low birth weight infants admitted within 7 days after birth to NICUs participating in the Pediatric Health Information System database, between January 1, 2005, and March 31, 2008, was performed. NICU medical directors were surveyed to determine attitudes and decision-making regarding adoption of vitamin A supplementation. The proportion of infants receiving vitamin A at each center was measured over time. Patient and hospital characteristics associated with vitamin A use were examined.

RESULTS

Among 4184 eligible infants cared for in 30 NICUs, 1005 infants (24%) received vitamin A. Eighteen centers (60%) used vitamin A for some patients. Infants discharged in 2007 (odds ratio: 2.7 [95% confidence interval: 1.4-5.3]) and 2008 (odds ratio: 2.8 [95% confidence interval: 1.4-5.8]), compared with 2005, were more likely to receive vitamin A. NICU medical directors from centers using vitamin A, compared with centers that did not adopt vitamin A supplementation, reported stronger beliefs in the efficacy of vitamin A to reduce the incidence of bronchopulmonary dysplasia (83% vs 33%; P = .03) and in the ease with which vitamin A could be implemented (75% vs 22%; P = .02).

CONCLUSIONS

Although the use of vitamin A is increasing, marked variation across NICUs remains. Provider attitudes and system characteristics seem to influence vitamin A adoption.

The influence of early postnatal nutrition on retinopathy of prematurity in extremely low birth weight infants

BACKGROUND

Retinopathy of prematurity(ROP) is the most common serious ophthalmic disease in preterm infants. Human milk may provide a protective effect for ROP; however, beneficial effects of human milk preclude randomized trials. Therefore, we conducted a retrospective analysis comparing early postnatal nutrition with ROP development.

OBJECTIVE

Evaluate relationship between early postnatal nutriture and ROP surgery.

DESIGN/METHODS

Nutrition data was collected for inborn AGA infants, BW 700-1000 g. ROP surgery was the primary outcome variable. A single pediatric ophthalmologist supervised examinations. All infants received triweekly IM vitamin A as chronic lung disease prophylaxis (Tyson: NEJM, 1999).

RESULTS

BW and gestational age were 867+/-85 g and 26.3+/-1.2 weeks (n=77, mean+/-1SD). ROP surgery infants(n=11) received more parenteral nutrition, 1648 mL, and less human milk, 13.8 mL/kg-day, and vitamin E, 1.4 mg/kg-day, during the second postnatal week. Human milk was a negative predictor for ROP surgery, odds ratio=0.94. Both groups met vitamin A recommendations; however, 74% was administered via IM injections. Neither group met vitamin E recommendations.

CONCLUSIONS

Human milk feeding, parenteral nutrition volume and vitamin E intake were predictors for ROP surgery. IM vitamin A injections provided the majority of vitamin A; vitamin E administration was insufficient. Improving human milk feeding rates and vitamin dosing options may affect ROP surgery rates.

Vitamin A is systemically bioavailable after intratracheal administration with surfactant in an animal model of newborn respiratory distress

Chronic lung disease (CLD) is a major cause of long-term morbidity in extremely LBW infants with respiratory distress syndrome. Parenteral vitamin A administration decreases the risk of CLD. We tested the hypothesis that intratracheal vitamin A administration with surfactant is systemically bioavailable without interfering with the functional properties of exogenous surfactant. Newborn piglets were ventilated with 100% FiO2 and sequential saline lavage induced respiratory distress syndrome. During lung injury induction, ventilator changes were allowed, but none were made following treatment allocation. Animals were assigned by chance in a blinded control trial to three groups: I=control; II=surfactant; III=surfactant+vitamin A. Hemodynamics, lung mechanics, and blood gases were measured following instrumentation, pre- and posttreatment for 4 h, at which time the liver was sampled for retinol determination. All parameters improved in animals receiving surfactant. A significant interaction existed between time and group for PaO2 and alveolar-arterial oxygen difference (A-aDO2). Hepatic levels of retinol were higher (p<0.001) in animals receiving retinyl acetate. Intratracheal administration of surfactant+vitamin A did not alter the beneficial effects of surfactant on lung compliance and gas exchange. Intratracheal Vitamin A was associated with rapid hepatic uptake. Further studies are warranted.

Surface activity of surfactant spiked with vitamin A

Background

Intramuscular injections of vitamin A decrease the risk of broncho-pulmonary dysplasia. Admixture of vitamin A with surfactant as a lipophilic vehicle might be a less invasive modality.

Aim

Test physical properties of surfactant + vitamin A.

Methods

Miscibility and surface activity were tested in surfactant supplemented with retinyl-acetate, -palmitate, 13-cis-, or all-trans-retinoic acid.

Results

Retinol acetate (5000 IU/mL) demonstrated miscibility with surfactant when premixing with ethanol. Its surface activity was 40% lower compared to surfactant alone.

Conclusion

These findings warrant preclinical studies to test whether administration of vitamin A in subjects requiring surfactant is associated with beneficial functional properties.

Improved vitamin A supplementation regimen for breastfed very low birth weight infants

OBJECTIVE

Preterm infants usually have low retinol status at birth and at discharge from hospital. We have evaluated a new protocol designed to improve plasma retinol in very low birth weight infants (VLBW, birth weight < 1500 g).

DESIGN

An open intervention trial was conducted in which vitamin A was given in a human milk fortifier. The daily dose of vitamin A varied according to bodyweight and was given mixed with human milk instead of as a bolus. Blood samples were collected at inclusion and at discharge from hospital. Plasma was analyzed for retinol using high-performance liquid chromatography. The daily intake of vitamin A and plasma retinol concentration was compared with the vitamin protocol normally used in Norwegian hospitals.

RESULTS

Sixty VLBW infants were included and 53 completed the study. At discharge from hospital, the reference group had lower median plasma retinol concentrations compared to the modified group (0.30 microM vs. 0.49 microM, p = 0.008). Fewer infants in the modified group had plasma retinol levels below 0.35 microM (indicating reduced hepatic stores) compared to infants in the reference group (44% vs. 69%, p = 0.04).

CONCLUSION

The modified protocol improved plasma retinol levels at discharge compared to the reference protocol.

Shielding parenteral multivitamins from light increases vitamin A and E concentration in lung of newborn guinea pigs

BACKGROUND & AIMS

Exposure of parenteral multivitamin preparation (MVP) to light generates peroxides. Light-exposed MVP induces an oxidant stress in lung but not in liver. This discrepancy suggests differences in handling of infused antioxidant vitamins between the two organs.

HYPOTHESIS

antioxidant capacity of lung depends on the MVP concentration and light protection of infused solutions.

METHODS

Protocol 1: four groups of three-day old guinea pigs received the base solution (5% dextrose + 0.45% NaCl) enriched with 0%, 1%, 2% and 3% MVP. Protocol 2: three further groups received the base solution + 2% MVP either light-exposed or light-protected or light-protected + 300 microM H2O2. After 4 days, lung and liver were sampled for vitamin determinations. Data were analyzed by ANOVA.

RESULTS

In lung, vitamins A-C-E reached a plateau with 1% MVP. In liver, vitamin A and E increased according to their concentration in solutions. Light exposure and added-H2O2 were associated with lower vitamin E in lung and liver. Retinol was higher in lung and lower in liver of animals receiving light-protected compared to light-exposed solutions.

CONCLUSIONS

Light protection of 1% MVP is a better way to improve the pulmonary oxidant-antioxidant balance than to increase MVP (>1%) in parenteral nutrition.

Pain relief for neonates in Australian hospitals: a need to improve evidence-based practice

OBJECTIVE

To ascertain the extent to which neonatal analgesia was used in Australia for minor invasive procedures as an indicator of evidence-based practice in neonatology.

METHODS

A cross-sectional telephone survey of hospitals in all Australian states and territories with more than 200 deliveries per year was carried out. Questions were asked regarding awareness of the benefits and the use of analgesia for minor invasive procedures in term and near term neonates. Analysis was undertaken according to state and territory, annual birth numbers and the level of neonatal nursery care available.

RESULTS

Data were available from 212 of 214 eligible hospitals. Of the total respondents, 51% and 70% respectively were aware of the benefits of sucrose and breast-feeding for neonatal analgesia. Eleven per cent of units administered sucrose before venepuncture and 25% of units used breast-feeding. Ten per cent of units used sucrose before heel prick with 49% utilizing breast-feeding. Expressed breast milk was used in 10% of units. Analgesia was given less frequently before intravenous cannulation compared to venepuncture and heel prick. Awareness and implementation of neonatal analgesia varied widely in the states and territories. There was a trend for hospitals providing a higher level of neonatal care to have a greater awareness of sucrose as an analgesic (P < 0.0001) and the use of sucrose for venepuncture (P = 0.029), heel prick (P = 0.025) and intravenous catheter insertion (P = 0.013). Similar trends were found on analysis according to birth number of the maternity units. Smaller units had a greater usage of breast-feeding as an analgesic for heel prick (P = 0.017).

CONCLUSION

Despite good evidence for the administration of sucrose and breast milk in providing effective analgesia for newborn infants, it is not widely used in Australia. It is imperative that the gap between research findings and clinical practice with regard to neonatal analgesia be addressed.

Management of neonatal abstinence syndrome in neonatal intensive care units: a national survey

AIMS

To determine the monitoring and treatment of neonatal abstinence syndrome (NAS) in neonatal intensive care units (NICUs) following opiate or polydrug exposure in utero.

METHODS

A pretested questionnaire was distributed via email to the chiefs of the neonatology divisions with accredited Fellowship programs in Neonatal-Perinatal Medicine in the United States.

RESULTS

Of the 102 individuals contacted, 75 participated in the survey. In all, 41 of the respondents (54.5%) have a written policy regarding the management of neonatal NAS. The method of Finnegan is the most commonly used abstinence scoring system (49 of 75, 65%), while only three respondents use the Lipsitz tool. Opioids (tincture of opium, or morphine sulfate solution) are used most commonly for management of both opioid (63% of respondents) and polydrug (52% of respondents) withdrawal, followed by phenobarbital (32 % of respondents) for polydrug withdrawal and methadone (20% of respondents) for opioid withdrawal. In all, 53 respondents (70%) use phenobarbital, and 19 (25%) use intravenous morphine to control opioid withdrawal seizures, while 61 (81%) use phenobarbital in cases of polydrug withdrawal seizures. Only 53 respondents (70%) always use an abstinence scoring system to determine when to start, titrate, or terminate pharmacologic treatment of neonatal NAS.

CONCLUSION

The management of neonatal psychomotor behavior consistent with withdrawal varies widely, with inconsistent policies to determine its presence or treatment. Only about half of NICUs have written guidelines for the management of NAS, which may preclude effective auditing of this practice. Educational interventions may be necessary to ensure changes in clinical practice.

Vitamin A and preterm infants: what we know, what we don't know, and what we need to know

Vitamin A is essential for optimal growth and development. In the developing world, vitamin A supplementation of the newborn infant reduces mortality. In the developed world, extremely preterm infants are born with low body stores of vitamin A and are at high risk of vitamin A deficiency. Optimal vitamin A supplementation for this population is not clearly defined, however, and, despite evidence of benefit, early vitamin A supplementation of extremely preterm infants is not uniformly practised in the United Kingdom. There is an urgent need for studies in preterm infants that include quantification of hepatic stores and functional assessment of vitamin A status as well as long term outcome.

Vitamin A supplementation for extremely low birth weight infants: outcome at 18 to 22 months

BACKGROUND

A National Institute of Child Health and Human Development Neonatal Research Network randomized trial showed that vitamin A supplementation reduced bronchopulmonary dysplasia (O2 at 36 weeks' postmenstrual age) or death in extremely low birth weight (ELBW) neonates (relative risk [RR]: 0.89). As with postnatal steroids or other interventions, it is important to ensure that there are no longer-term adverse effects that outweigh neonatal benefits.

PRIMARY OBJECTIVE

To determine if vitamin A supplementation in ELBW infants during the first month after birth affects survival without neurodevelopmental impairment at a corrected age of 18 to 22 months.

DESIGN/METHODS

Infants enrolled in the National Institute of Child Health and Human Development vitamin A trial were evaluated at 18 to 22 months by carefully standardized assessments: Bayley Mental Index (MDI) and Psychomotor Index (PDI), visual and hearing screens, and physical examination for cerebral palsy (CP). The medical history was also obtained. Neurodevelopmental impairment (NDI) was predefined as > or =1 of MDI <70, PDI <70, CP, blind in both eyes, or hearing aids in both ears.

RESULTS

Of 807 enrolled infants, 133 died before and 16 died after discharge. Five hundred seventy-nine (88%) of the 658 remaining infants were followed up. The primary outcome of NDI or death could be determined for 687 of 807 randomized infants (85%). Baseline characteristics and predischarge and postdischarge mortality were comparable in both study groups. NDI or death by 18 to 22 months occurred in 190 of 345 (55%) infants in the vitamin A group and in 204 of 342 (60%) of the control group (RR: 0.94; 95% confidence interval: 0.80-1.07). RRs for low MDI, low PDI, and CP were also <1.0. We found no evidence that neonatal vitamin A supplementation reduces hospitalizations or pulmonary problems after discharge.

CONCLUSION

Vitamin A supplementation for ELBW infants reduces bronchopulmonary dysplasia without increasing mortality or neurodevelopmental impairment at 18 to 22 months. However, this study was not powered to evaluate small magnitudes of change in long-term outcomes.