Use of neonatal lung ultrasound in European neonatal units: a survey by the European Society of Paediatric Research

OBJECTIVE

Regarding the use of lung ultrasound (LU) in neonatal intensive care units (NICUs) across Europe, to assess how widely it is used, for what indications and how its implementation might be improved.

DESIGN AND INTERVENTION

International online survey.

RESULTS

Replies were received from 560 NICUs in 24 countries between January and May 2023. LU uptake varied considerably (20%-98% of NICUs) between countries. In 428 units (76%), LU was used for clinical indications, while 34 units (6%) only used it for research purposes. One-third of units had <2 years of experience, and only 71 units (13%) had >5 years of experience. LU was mainly performed by neonatologists. LU was most frequently used to diagnose respiratory diseases (68%), to evaluate an infant experiencing acute clinical deterioration (53%) and to guide surfactant treatment (39%). The main pathologies diagnosed by LU were pleural effusion, pneumothorax, transient tachypnoea of the newborn and respiratory distress syndrome. The main barriers for implementation were lack of experience with technical aspects and/or image interpretation. Most units indicated that specific courses and an international guideline on neonatal LU could promote uptake of this technique.

CONCLUSIONS

Although LU has been adopted in neonatal care in most European countries, the uptake is highly variable. The main indications are diagnosis of lung disease, evaluation of acute clinical deterioration and guidance of surfactant. Implementation may be improved by developing courses and publishing an international guideline.

Association between patent ductus arteriosus flow and home oxygen therapy in extremely preterm infants

BACKGROUND

Central blood flow measurements include the estimation of right and left ventricular output (RVO, LVO), superior vena cava (SVC) flow, and calculated patent ductus arteriosus (PDA) flow. We aimed to provide an overview of the maturation patterns of these values and the relationship between PDA flow and the need for home oxygen therapy.

METHODS

This prospective single-center study was conducted in infants born at <26 weeks of gestation. We performed echocardiographic measurements five times during their life (from the 4th post-natal day to the 36th postmenstrual week).

RESULTS

Sixty patients with a mean birth weight of 680 (590, 760) g were included. Postnatal development of LVO and PDA flow peaked at the end of the second postnatal week (427 and 66 mL/kg/min, respectively). The RVO increased between days 4 and 7-8. The SVCF was most stable. The development curves of PDA flow differed between the groups with (n = 28; 47%) and without home oxygen therapy.

CONCLUSION

We present the central blood flow values and their postnatal development in infants <26 weeks of gestation. This study demonstrates the association between PDA flow and the future need for home oxygen therapy.

IMPACT

This study enriches our knowledge of the long-term development of central blood flow parameters and derived patent ductus arteriosus (PDA) flow in extremely preterm infants (<26 weeks). While pulmonary resistance decreased, PDA flow continued to increase from day 4 to the end of the second week of life. Similarly, left ventricular output increased as a marker of preload. The superior vena cava flow remained stable. The observed association between PDA flow and an unfavorable respiratory outcome is important for future studies focusing on the prevention of chronic lung disease.

Prophylactic Oropharyngeal Surfactant for Preterm Newborns at Birth: A Randomized Clinical Trial

Importance

Preterm newborns at risk of respiratory distress syndrome are supported with continuous positive airway pressure (CPAP). Many newborns worsen despite CPAP and are intubated for surfactant administration, an effective therapy for treatment of respiratory distress syndrome. Endotracheal intubation is associated with adverse effects. Pharyngeal administration of surfactant to preterm animals and humans has been reported as an alternative.

Objective

To assess whether giving prophylactic oropharyngeal surfactant to preterm newborns at birth would reduce the rate of intubation for respiratory failure.

Design, Setting, and Participants

This unblinded, parallel-group randomized clinical trial (Prophylactic Oropharyngeal Surfactant for Preterm Infants [POPART]) was conducted from December 17, 2017, to September 11, 2020, at 9 tertiary neonatal intensive care units in 6 European countries. Newborns born before 29 weeks of gestation without severe congenital anomalies, for whom intensive care was planned, were eligible for inclusion. The data were analyzed from July 27, 2022, to June 20, 2023.

Intervention

Newborns were randomly assigned to receive oropharyngeal surfactant at birth in addition to CPAP or CPAP alone. Randomization was stratified by center and gestational age (GA).

Main Outcomes and Measures

The primary outcome was intubation in the delivery room for bradycardia and/or apnea or in the neonatal intensive care unit for prespecified respiratory failure criteria within 120 hours of birth. Caregivers were not masked to group assignment.

Results

Among 251 participants (mean [SD] GA, 26 [1.5] weeks) who were well matched at study entry, 126 (69 [54.8%] male) with a mean (SD) birth weight of 858 (261) grams were assigned to the oropharyngeal surfactant group, and 125 (63 [50.4%] male) with a mean (SD) birth weight of 829 (253) grams were assigned to the control group. The proportion of newborns intubated within 120 hours was not different between the groups (80 [63.5%) in the oropharyngeal surfactant group and 81 [64.8%] in the control group; relative risk, 0.98 [95% CI, 0.81-1.18]). More newborns assigned to the oropharyngeal surfactant group were diagnosed with and treated for pneumothorax (21 [16.6%] vs 8 [6.4%]; P = .04).

Conclusions and Relevance

This randomized clinical trial found that administration of prophylactic oropharyngeal surfactant to newborns born before 29 weeks' GA did not reduce the rate of intubation in the first 120 hours of life. These findings suggest that administration of surfactant into the oropharynx immediately after birth in addition to CPAP should not be routinely used.

Trial Registration

EudraCT: 2016-004198-41.

European Consensus Guidelines on the Management of Respiratory Distress Syndrome: 2022 Update

Respiratory distress syndrome (RDS) care pathways evolve slowly as new evidence emerges. We report the sixth version of "European Guidelines for the Management of RDS" by a panel of experienced European neonatologists and an expert perinatal obstetrician based on available literature up to end of 2022. Optimising outcome for babies with RDS includes prediction of risk of preterm delivery, appropriate maternal transfer to a perinatal centre, and appropriate and timely use of antenatal steroids. Evidence-based lung-protective management includes initiation of non-invasive respiratory support from birth, judicious use of oxygen, early surfactant administration, caffeine therapy, and avoidance of intubation and mechanical ventilation where possible. Methods of ongoing non-invasive respiratory support have been further refined and may help reduce chronic lung disease. As technology for delivering mechanical ventilation improves, the risk of causing lung injury should decrease, although minimising time spent on mechanical ventilation by targeted use of postnatal corticosteroids remains essential. The general care of infants with RDS is also reviewed, including emphasis on appropriate cardiovascular support and judicious use of antibiotics as being important determinants of best outcome. We would like to dedicate this guideline to the memory of Professor Henry Halliday who died on November 12, 2022.These updated guidelines contain evidence from recent Cochrane reviews and medical literature since 2019. Strength of evidence supporting recommendations has been evaluated using the GRADE system. There are changes to some of the previous recommendations as well as some changes to the strength of evidence supporting recommendations that have not changed. This guideline has been endorsed by the European Society for Paediatric Research (ESPR) and the Union of European Neonatal and Perinatal Societies (UENPS).

A Randomized, Controlled Trial to Investigate the Efficacy of Nebulized Poractant Alfa in Premature Babies with Respiratory Distress Syndrome

OBJECTIVE

To investigate the efficacy and safety of nebulized poractant alfa (at 200 and 400 mg/kg doses) delivered in combination with nasal continuous positive airway pressure compared with nasal continuous positive airway pressure alone in premature infants with diagnosed respiratory distress syndrome.

STUDY DESIGN

This randomized, controlled, multinational study was conducted in infants at 28^0/7 to 32^6/7 weeks of gestation. The primary outcome was the incidence of respiratory failure in the first 72 hours of life, defined as needing endotracheal surfactant and/or mechanical ventilation owing to prespecified criteria. Secondary outcomes included the time to respiratory failure in the first 72 hours, duration of ventilation, mortality, incidence of bronchopulmonary dysplasia, and major associated neonatal comorbidities. In addition, the safety and tolerability of the treatments were assessed reporting the number and percentage of infants with treatment-emergent adverse events and adverse drug reactions during nebulization.

RESULTS

In total, 129 infants were randomized. No significant differences were observed for the primary outcome: 24 (57%), 20 (49%), and 25 (58%) infants received endotracheal surfactant and/or mechanical ventilation within 72 hours in the poractant alfa 200 mg/kg, poractant alfa 400 mg/kg, and nasal continuous positive airway pressure groups, respectively. Similarly, secondary respiratory outcomes did not differ among groups. Enrollment was halted early owing to a change in the benefit-risk balance of the intervention. Nebulized poractant alfa was well-tolerated and safe, and no serious adverse events were related to the study treatment.

CONCLUSIONS

The intervention did not decrease the likelihood of respiratory failure within the first 72 hours of life.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03235986.

A first-in-human clinical study of a new SP-B and SP-C enriched synthetic surfactant (CHF5633) in preterm babies with respiratory distress syndrome: two-year outcomes

OBJECTIVE

To assess at 24 months corrected age (CA) the neurological, respiratory, and general health status of children born prematurely from 27⁺⁰ to 33⁺⁶ weeks' gestation who were treated in a first-in-human study with a new fully synthetic surfactant (CHF5633) enriched with SP-B and SP-C proteins.

OUTCOME MEASURES

Children were assessed using Bayley Scales of Infant Development (BSID), with a score below normal defined as BSID-II Mental Development Index score <70, or BSID-III cognitive composite score <85. In addition, a health status questionnaire was used to check for functional disability including respiratory problems and related treatments, sensory and neurodevelopment assessments, communication skills as well as the number of hospitalizations.

RESULTS

35 of 39 survivors had a neurodevelopmental assessment, 24 infants being evaluated by Bayley's Scales and 11 by health status questionnaires only. 23 children had scores within normal limits and one had BSID-III <85. The remaining 11 were judged clinically to have normal development. Health status questionnaires detected only issues that would normally be expected in preterm-born children.

CONCLUSIONS

This assessment offers reassurance that treatment with CHF5633 surfactant was not associated with adverse neurodevelopmental, respiratory, or health outcomes by two years corrected age.

Comparing the effect of two different interfaces on breathing of preterm infants at birth: A matched-pairs analysis

OBJECTIVE

Applying a face mask could provoke a trigeminocardiac reflex. We compared the effect of applying bi-nasal prongs with a face mask on breathing and heart rate of preterm infants at birth.

METHODS

In a retrospective matched-pairs study of infants <32 weeks of gestation, the use of bi-nasal prongs for respiratory support at birth was compared to the use of a face mask. Infants who were initially breathing at birth and subsequently received respiratory support were matched for gestational age (±4 days), birth weight (±300 g), general anaesthesia and gender. Breathing, heart rate and other parameters were collected before and after interface application and in the first 5 min thereafter.

RESULTS

In total, 130 infants were included (n = 65 bi-nasal prongs, n = 65 face mask) with a median (IQR) gestational age of 27⁺² (25⁺³-28⁺⁴) vs 26⁺⁶ (25⁺³-28⁺⁵) weeks. The proportion of infants who stopped breathing after applying the interface was not different between the groups (bi-nasal prongs 43/65 (66%) vs face mask 46/65 (71%), p = 0.70). Positive pressure ventilation was given more often when bi-nasal prongs were used (55/65 (85%) vs 40/65 (62%), p < 0.001). Heart rate (101 (75-145) vs 110 (68-149) bpm, p = 0.496) and oxygen saturation (59% (48-87) vs 56% (35-84), p = 0.178) were similar in the first 5 min after an interface was applied in the infants who stopped breathing.

CONCLUSION

Apnoea and bradycardia occurred often after applying either bi-nasal prongs or a face mask on the face for respiratory support in preterm infants at birth.

Early inhaled budesonide in extremely preterm infants decreases long-term respiratory morbidity

BACKGROUND

There is no strict correlation between early bronchopulmonary dysplasia and long-term respiratory disease. Early inhaled corticosteroids seem to reduce the incidence of bronchopulmonary dysplasia, but the long-term outcome remains unknown.

RESEARCH QUESTION

The aim of this study was to evaluate the effect of early inhaled corticosteroids on chronic respiratory morbidity.

METHODS

Fifty-nine survivors from the Prague cohort included in Neonatal European Study of Inhaled Steroids underwent further follow-up comprising of respiratory morbidity monitoring during the first 2 years of life followed by objective lung function testing performed at the age of 5.9 years (range 5-7 years). Both outcomes were pursued and finalized before the unblinding of budesonide subgroups.

RESULTS

Fifty randomized (budesonide vs placebo group, 56% vs 44%) survivors were included in the study. Spirometry was successfully performed in 48 children. No statistically significant differences were found in the lung function test (forced expiratory flow [FEF] - FEF₇₅ , FEF_50, FEF₂₅ , and FEF_25-75; FEV₁ , forced vital capacity [FVC], FEV₁ /FVC) although mild trend to the improvement of expiratory flow pattern was observed in the budesonide group (median z-score of FEV₁ /FVC -0.376 vs -0.983, P = .13; median z-score of FEF_25-75 -1.004 vs -1.458, P = .13; median z-score of FEF₇₅ -0.527 vs -0.996, P = .17). Children assigned to budesonide had a significantly lower rate of symptoms of chronic lung disease (34.6% vs 68.2%; P = .04) than children assigned to placebo.

INTERPRETATION

Our study suggests that early inhaled budesonide was associated with the trend to the improvement of functional lung parameters and with a lower rate of symptoms of chronic lung disease within the first 2 years of life.

A novel accurate LC-MS/MS method for quantitative determination of Z-lumirubin

Although phototherapy (PT) is a standard treatment for neonatal jaundice, no validated clinical methods for determination of bilirubin phototherapy products are available. Thus, the aim of our study was to establish a such method for clinical use. To achieve this aim, a LC-MS/MS assay for simultaneous determination of Z-lumirubin (LR) and unconjugated bilirubin (UCB) was conducted. LR was purified after irradiation of UCB at 460 nm. The assay was tested on human sera from PT-treated neonates. Samples were separated on a HPLC system with a triple quadrupole mass spectrometer detector. The instrument response was linear up to 5.8 and 23.4 mg/dL for LR and UCB, respectively, with submicromolar limits of detection and validity parameters relevant for use in clinical medicine. Exposure of newborns to PT raised serum LR concentrations three-fold (p < 0.01), but the absolute concentrations were low (0.37 ± 0.16 mg/dL), despite a dramatic decrease of serum UCB concentrations (13.6 ± 2.2 vs. 10.3 ± 3.3 mg/dL, p < 0.01). A LC-MS/MS method for the simultaneous determination of LR and UCB in human serum was established and validated for clinical use. This method should help to monitor neonates on PT, as well as to improve our understanding of both the kinetics and biology of bilirubin phototherapy products.

European Consensus Guidelines on the Management of Respiratory Distress Syndrome - 2019 Update

As management of respiratory distress syndrome (RDS) advances, clinicians must continually revise their current practice. We report the fourth update of "European Guidelines for the Management of RDS" by a European panel of experienced neonatologists and an expert perinatal obstetrician based on available literature up to the end of 2018. Optimising outcome for babies with RDS includes prediction of risk of preterm delivery, need for appropriate maternal transfer to a perinatal centre and timely use of antenatal steroids. Delivery room management has become more evidence-based, and protocols for lung protection including initiation of CPAP and titration of oxygen should be implemented immediately after birth. Surfactant replacement therapy is a crucial part of management of RDS, and newer protocols for its use recommend early administration and avoidance of mechanical ventilation. Methods of maintaining babies on non-invasive respiratory support have been further developed and may cause less distress and reduce chronic lung disease. As technology for delivering mechanical ventilation improves, the risk of causing lung injury should decrease, although minimising time spent on mechanical ventilation using caffeine and, if necessary, postnatal steroids are also important considerations. Protocols for optimising general care of infants with RDS are also essential with good temperature control, careful fluid and nutritional management, maintenance of perfusion and judicious use of antibiotics all being important determinants of best outcome.

Nonhydroxylated 1-O-acylceramides in vernix caseosa

Vernix caseosa, the waxy substance that coats the skin of newborn babies, has an extremely complex lipid composition. We have explored these lipids and identified nonhydroxylated 1-O-acylceramides (1-O-ENSs) as a new class of lipids in vernix caseosa. These ceramides mostly contain saturated C11-C38 ester-linked (1-O) acyls, saturated C12-C39 amide-linked acyls, and C16-C24 sphingoid bases. Because their fatty acyl chains are frequently branched, numerous molecular species were separable and detectable by HPLC/MS: we found more than 2,300 molecular species, 972 of which were structurally characterized. The most abundant 1-O-ENSs contained straight-chain and branched fatty acyls with 20, 22, 24, or 26 carbons in the 1-O position, 24 or 26 carbons in the N position, and sphingosine. The 1-O-ENSs were isolated using multistep TLC and HPLC and they accounted for 1% of the total lipid extract. The molecular species of 1-O-ENSs were separated on a C18 HPLC column using an acetonitrile/propan-2-ol gradient and detected by APCI-MS, and the structures were elucidated by high-resolution and tandem MS. Medium-polarity 1-O-ENSs likely contribute to the cohesiveness and to the waterproofing and moisturizing properties of vernix caseosa.

Proactive approach at the limits of viability improves the short-term outcome of neonates born after 23 weeks' gestation

OBJECTIVE

The aim of this single-center study was to identify factors that affect the short-term outcome of newborns delivered around the limits of viability.

METHODS

A group of 137 pregnant women who gave birth between 22+0/7 and 25+6/7 weeks of gestation was retrospectively studied. The center supports a proactive approach to infants around the limits of viability. Perinatal and neonatal characteristics were obtained and statistically evaluated.

RESULTS

A total of 166 live-born infants were enrolled during a 6-year period; 162 (97.6%) of them were admitted to the neonatal intensive care unit (ICU) and 119 (73.5%) survived until discharge. The decrease in neonatal mortality was associated with an advanced gestational age (P<0.001) and a completed course of corticosteroids (P=0.002). Neonatal morbidities were common among infants of all gestational ages. The incidence of severe intraventricular hemorrhage significantly depended on gestational age (P<0.001) and a completed course of corticosteroids (P=0.002). Survival without severe neonatal morbidities was 39.5% and occurred mostly after 24+0/7 weeks of gestation.

CONCLUSION

The short-term outcome of newborns delivered around the limits of viability is mostly affected by gestational age and antenatal corticosteroid treatment. A consistently proactive approach improves the survival of infants at the limits of viability. This is most pronounced in cases where the delivery is delayed beyond 24 completed gestational weeks.

Long-Term Effects of Inhaled Budesonide for Bronchopulmonary Dysplasia

BACKGROUND

The long-term effects on neurodevelopment of the use of inhaled glucocorticoids in extremely preterm infants for the prevention or treatment of bronchopulmonary dysplasia are uncertain.

METHODS

We randomly assigned 863 infants (gestational age, 23 weeks 0 days to 27 weeks 6 days) to receive early (within 24 hours after birth) inhaled budesonide or placebo. The prespecified secondary long-term outcome was neurodevelopmental disability among survivors, defined as a composite of cerebral palsy, cognitive delay (a Mental Development Index score of <85 [1 SD below the mean of 100] on the Bayley Scales of Infant Development, Second Edition, with higher scores on the scale indicating better performance), deafness, or blindness at a corrected age of 18 to 22 months.

RESULTS

Adequate data on the prespecified composite long-term outcome were available for 629 infants. Of these infants, 148 (48.1%) of 308 infants assigned to budesonide had neurodevelopmental disability, as compared with 165 (51.4%) of 321 infants assigned to placebo (relative risk, adjusted for gestational age, 0.93; 95% confidence interval [CI], 0.80 to 1.09; P=0.40). There was no significant difference in any of the individual components of the prespecified outcome. There were more deaths in the budesonide group than in the placebo group (82 [19.9%] of 413 infants vs. 58 [14.5%] of 400 infants for whom vital status was available; relative risk, 1.37; 95% CI, 1.01 to 1.86; P=0.04).

CONCLUSIONS

Among surviving extremely preterm infants, the rate of neurodevelopmental disability at 2 years did not differ significantly between infants who received early inhaled budesonide for the prevention of bronchopulmonary dysplasia and those who received placebo, but the mortality rate was higher among those who received budesonide. (Funded by the European Union and Chiesi Farmaceutici; ClinicalTrials.gov number, NCT01035190 .).

Oropharyngeal surfactant can improve initial stabilisation and reduce rescue intubation in infants born below 25 weeks of gestation

AIM

Minimally aggressive and easily performed techniques that facilitate spontaneous respiratory stabilisation are required to reduce rescue intubation in extremely premature infants. This study evaluated the feasibility and safety of administering surfactant into the pharynx of infants born at <25 weeks immediately after birth.

METHODS

This study of 19 infants was conducted from January 2013 to June 2014 in a tertiary perinatal centre in Prague. We administered 1.5 mL of Curosurf as a bolus into the pharynx and simultaneously performed a sustained inflation manoeuvre (SIM). The extent of the interventions, death and severe neonatal morbidity in the study group were compared with 20 controls born before the study period and 20 born after it.

RESULTS

All infants received oropharyngeal surfactant within the median (interquartile range) time of 40 seconds (25-75) after cord camping. The surfactant had to be suctioned in one infant because of upper airway obstruction. Although more subsequent surfactant was administered in the study group, significantly fewer study period infants required intubation than the before and after controls (16% versus 75% and 58%, respectively, p < 0.01).

CONCLUSION

Oropharyngeal surfactant with simultaneous SIM was feasible and safe and reduced the need for delivery room intubation in these fragile infants.

A first-in-human clinical study of a new SP-B and SP-C enriched synthetic surfactant (CHF5633) in preterm babies with respiratory distress syndrome

OBJECTIVE

CHF5633 (Chiesi Farmaceutici S.p.A., Parma, Italy) is the first fully synthetic surfactant enriched by peptide analogues of two human surfactant proteins. We planned to assess safety and tolerability of CHF5633 and explore preliminary efficacy.

DESIGN

Multicentre cohort study.

PATIENTS

Forty infants from 27⁺⁰ to 33⁺⁶ weeks gestation with respiratory distress syndrome requiring fraction of inspired oxygen (FiO₂) ≥0.35 were treated with a single dose of CHF5633 within 48 hours after birth. The first 20 received 100 mg/kg and the second 20 received 200 mg/kg.

OUTCOME MEASURES

Adverse events (AEs) and adverse drug reactions (ADRs) were monitored with complications of prematurity considered AEs if occurring after dosing. Systemic absorption and immunogenicity were assessed. Efficacy was assessed by change in FiO₂ after dosing and need for poractant-alfa rescue.

RESULTS

Rapid and sustained improvements in FiO₂ were observed in 39 (98%) infants. One responded neither to CHF5633 nor two poractant-alfa doses. A total of 79 AEs were experienced by 19 infants in the 100 mg/kg cohort and 53 AEs by 20 infants in the 200 mg/kg cohort. Most AEs were expected complications of prematurity. Two unrelated serious AEs occurred in the second cohort. One infant died of necrotising enterocolitis and another developed viral bronchiolitis after discharge. The single ADR was an episode of transient endotracheal tube obstruction following a 200 mg/kg dose. Neither systemic absorption, nor antibody development to either peptide was detected.

CONCLUSIONS

Both CHF5633 doses were well tolerated and showed promising clinical efficacy profile. These encouraging data provide a basis for ongoing randomised controlled trials.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT01651637.

Cholesteryl esters of ω-(O-acyl)-hydroxy fatty acids in vernix caseosa

Cholesteryl esters of ω-(O-acyl)-hydroxy FAs (Chl-ωOAHFAs) were identified for the first time in vernix caseosa and characterized using chromatography and MS. Chl-ωOAHFAs were isolated using adsorption chromatography on silica gel and magnesium hydroxide. Their general structure was established using high-resolution and tandem MS of intact lipids, and products of their transesterification and derivatizations. Individual molecular species were characterized using nonaqueous reversed-phase HPLC coupled to atmospheric pressure chemical ionization. The analytes were detected as protonated molecules, and their structures were elucidated in the negative ion mode using controlled thermal decomposition and data-dependent fragmentation. About three hundred molecular species of Chl-ωOAHFAs were identified in this way. The most abundant Chl-ωOAHFAs contained 32:1 ω-hydroxy FA (ω-HFA) and 14:0, 15:0, 16:0, 16:1, and 18:1 FAs. The double bond in the 32:1 ω-HFA was in the n-7 and n-9 positions. Chl-ωOAHFAs are estimated to account for approximately 1-2% of vernix caseosa lipids.

European Consensus Guidelines on the Management of Respiratory Distress Syndrome - 2016 Update

Advances in the management of respiratory distress syndrome (RDS) ensure that clinicians must continue to revise current practice. We report the third update of the European Guidelines for the Management of RDS by a European panel of expert neonatologists including input from an expert perinatal obstetrician based on available literature up to the beginning of 2016. Optimizing the outcome for babies with RDS includes consideration of when to use antenatal steroids, and good obstetric practice includes methods of predicting the risk of preterm delivery and also consideration of whether transfer to a perinatal centre is necessary and safe. Methods for optimal delivery room management have become more evidence based, and protocols for lung protection, including initiation of continuous positive airway pressure and titration of oxygen, should be implemented from soon after birth. Surfactant replacement therapy is a crucial part of the management of RDS, and newer protocols for surfactant administration are aimed at avoiding exposure to mechanical ventilation, and there is more evidence of differences among various surfactants in clinical use. Newer methods of maintaining babies on non-invasive respiratory support have been developed and offer potential for greater comfort and less chronic lung disease. As technology for delivering mechanical ventilation improves, the risk of causing lung injury should decrease although minimizing the time spent on mechanical ventilation using caffeine and if necessary postnatal steroids are also important considerations. Protocols for optimizing the general care of infants with RDS are also essential with good temperature control, careful fluid and nutritional management, maintenance of perfusion and judicious use of antibiotics all being important determinants of best outcome.

Premature infants born at <25 weeks of gestation may be compromised by currently recommended resuscitation techniques

AIM

Standard resuscitation guidelines are based on data from a range of gestational ages. We sought to evaluate the effectiveness of our delivery room resuscitation protocol across a range of gestational ages in preterm infants born at <29 weeks.

METHODS

We performed an observational study of prospectively collected video recordings of 73 preterm infants. The percentage of bradycardic patients, time to reach target oxygen saturation and the extent of all interventions were compared between three gestational age groups: 22-24 weeks (n = 22), 25-26 weeks (n = 27) and 27-28 weeks (n = 24).

RESULTS

Although the same resuscitation protocol was followed for all infants, bradycardic infants born <25 weeks responded poorly and required significantly longer to reach oxygen saturation targets of >70%, >80% and >90% (p < 0.03). They required significantly more interventions and had higher rate of death (p < 0.05) and severe intraventricular haemorrhage (p < 0.03). Significantly lower heart rate and oxygen saturation values were found in infants with intraventricular haemorrhage.

CONCLUSION

Current recommendations for resuscitation may fail to achieve timely lung aeration in infants born at the borderline of viability, leading to higher mortality and morbidity. Sustained inflation and delayed cord clamping may be effective alternatives.

Early Inhaled Budesonide for the Prevention of Bronchopulmonary Dysplasia

BACKGROUND

Systemic glucocorticoids reduce the incidence of bronchopulmonary dysplasia among extremely preterm infants, but they may compromise brain development. The effects of inhaled glucocorticoids on outcomes in these infants are unclear.

METHODS

We randomly assigned 863 infants (gestational age, 23 weeks 0 days to 27 weeks 6 days) to early (within 24 hours after birth) inhaled budesonide or placebo until they no longer required oxygen and positive-pressure support or until they reached a postmenstrual age of 32 weeks 0 days. The primary outcome was death or bronchopulmonary dysplasia, confirmed by means of standardized oxygen-saturation monitoring, at a postmenstrual age of 36 weeks.

RESULTS

A total of 175 of 437 infants assigned to budesonide for whom adequate data were available (40.0%), as compared with 194 of 419 infants assigned to placebo for whom adequate data were available (46.3%), died or had bronchopulmonary dysplasia (relative risk, stratified according to gestational age, 0.86; 95% confidence interval [CI], 0.75 to 1.00; P=0.05). The incidence of bronchopulmonary dysplasia was 27.8% in the budesonide group versus 38.0% in the placebo group (relative risk, stratified according to gestational age, 0.74; 95% CI, 0.60 to 0.91; P=0.004); death occurred in 16.9% and 13.6% of the patients, respectively (relative risk, stratified according to gestational age, 1.24; 95% CI, 0.91 to 1.69; P=0.17). The proportion of infants who required surgical closure of a patent ductus arteriosus was lower in the budesonide group than in the placebo group (relative risk, stratified according to gestational age, 0.55; 95% CI, 0.36 to 0.83; P=0.004), as was the proportion of infants who required reintubation (relative risk, stratified according to gestational age, 0.58; 95% CI, 0.35 to 0.96; P=0.03). Rates of other neonatal illnesses and adverse events were similar in the two groups.

CONCLUSIONS

Among extremely preterm infants, the incidence of bronchopulmonary dysplasia was lower among those who received early inhaled budesonide than among those who received placebo, but the advantage may have been gained at the expense of increased mortality. (Funded by the European Union and Chiesi Farmaceutici; ClinicalTrials.gov number, NCT01035190.).

Efficacy of FiO2 increase during the initial resuscitation of premature infants < 29 weeks: an observational study

OBJECTIVE

To evaluate the heart rate (HR) and oxygen saturation (SpO2) at 15-second intervals within 60 seconds after incremental increases of fractional inspired oxygen (FiO2) during resuscitation of infants younger than 29 weeks requiring two different forms of ventilatory support.

STUDY DESIGN

Retrospective observational study.

METHODS

Forty-three infants were stabilized, 14 by continuous positive airway pressure exclusively (CPAP group), and 29 by positive pressure ventilation (PPV group). Both groups received ventilatory support in a special bed with two cameras enabling the evaluation of all interventions including HR, SpO2, FiO2, positive inflation pressure, and positive end-expiratory pressure values. FiO2 was commenced at 0.30 and titrated in 0.1-0.2 increments every 30-60 seconds. The relationships between the incremental increases of FiO2 and related SpO2 and HR changes were evaluated.

RESULTS

Although there was an inverse correlation between initial FiO2 and SpO2 in both groups, a significant positive correlation between the incremental increase of FiO2 and SpO2 changes after 30 seconds was found only in the CPAP group. Only higher initial levels of FiO2 had a positive effect on the improvement in SpO2 in the PPV group.

CONCLUSION

The efficacy of FiO2 titration in 0.1-0.2 increments may be attenuated and delayed in extremely preterm infants required PPV during the first 6 minutes of life.

European consensus guidelines on the management of neonatal respiratory distress syndrome in preterm infants--2013 update

Despite recent advances in the perinatal management of neonatal respiratory distress syndrome (RDS), controversies still exist. We report updated recommendations of a European Panel of expert neonatologists who developed consensus guidelines after critical examination of the most up-to-date evidence in 2007 and 2010. This second update of the guidelines is based upon published evidence up to the end of 2012. Strong evidence exists for the role of antenatal steroids in RDS prevention, but it is still not clear if the benefit of repeated courses on respiratory outcomes outweighs the risk of adverse outcomes in the short and long term. Many practices involved in preterm neonatal stabilization at birth are not evidence based, including oxygen administration and positive pressure lung inflation, and they may at times be harmful. Surfactant replacement therapy is crucial in the management of RDS but the best preparation, optimal dose and timing of administration at different gestations is not completely clear. In addition, use of very early continuous positive airway pressure (CPAP) has altered the indications for prophylactic surfactant administration. Respiratory support in the form of mechanical ventilation may be lifesaving but can cause lung injury, and protocols should be directed at avoiding mechanical ventilation where possible by using non-invasive respiratory support such as CPAP. For babies with RDS to have best outcomes, it is essential that they have optimal supportive care, including maintenance of normal body temperature, proper fluid management, good nutritional support, appropriate management of the ductus arteriosus and support of the circulation to maintain adequate tissue perfusion.

[Acute or expectant management in premature labour with preterm premature rupture of the membranes?]

OBJECTIVE

To evaluate current knowledge about the management of preterm premature rupture of the membranes (PPROM).

DESIGN

Review article.

SETTING

Perinatological center, Department of Gynecology and Obstetrics, General Faculty Hospital and 1st Medical School of Charles University, Prague.

METHODS AND RESULTS

Expectant management in case of PPROM increases the incidence of infection/ inflammation but does not statistically increase mortality and serious morbidity of the infants. The incidence of infants morbidity corresponds with gestational age. The most serious complications occur in the lower gestational age. It is necessary to take an individual approach. The acute management increases the number of operative deliveries and respiratory distress syndrome (RDS) in the infants. The combination of RDS, extremely prematurity and hypoxia during the labour decreases the infants survival rate.

CONCLUSIONS

The prolongation of the latency period in pregnancies above 28th week does not deteriorate the neonatal mortality or morbidity.

Post-natal growth of 157 children born as extremely premature neonates

AIM

With increasing survival rate of extremely premature neonates, their long-term outcomes including growth and risk factors for later disorders need to be considered. We prospectively evaluated anthropometric parameters in children born as extremely premature neonates.

METHODS

Anthropometric parameters were measured at the ages of 2 and 5 years in 72 extremely premature children born between the 22nd and 25 + 6th weeks of gestation (group I) and 85 children born between the 26th and 27 + 6th weeks of gestation (group II).

RESULTS

Although catch-up in the postnatal growth was observed in both groups of children, resulting in growth improvement, the height of the extremely premature children at the ages of 2 and 5 years remains lower (P < 0.01) compared with the control population. A decline in head growth was observed in both groups between the ages of 2 and 5 years, resulting in decrease of standard deviation score (SDS) for head circumference (HC) in comparison with that of the control population, accompanied by an increased number of children with microcephaly, defined as HC < -2 SD. At the age of five, microcephaly was found in 18% of children from group I and 11.7% of children from group II. At the age of 5 years, the waist and hip circumferences and ten skinfolds were not different between both groups of children.

CONCLUSION

Long-term follow-up of extremely premature neonates is important not only to establish their growth patterns but also for risk factors assessment including adiposity for later development of adult-onset diseases.

Five-year survival without major disability of extremely preterm infants born at 22-27 weeks' gestation admitted to a NICU

AIM

To compare the 5-year survival without major disability in infants born at the threshold of viability at 22-25 weeks who were actively treated in the delivery room and admitted to a NICU to that of those born at 26-27 weeks of gestation.

METHODS

All infants between 22(+0) and 27(+6) weeks of gestation admitted to a regional intensive care unit during 1999-2003 were enrolled prospectively. The survival and major disability at 5 years of age were analysed by gestational age.

RESULTS

Of 242 treated infants, 202 survived (83.5%). Although the overall survival rate was significantly higher in the 25-27 weeks' gestation infants than the 22-24 weeks' gestation infants (p < 0.001), the survival rate among infants 22-24 weeks (63.6%, 63.6%, and 70%) did not significantly differ, likewise infants 25-27 weeks (88.7%, 90.6%, and 92%) had similar results. Overall, 28 children (14.4% of assessed) had major disability. Both survival and survival without major disability were positively influenced by increasing gestational age, increasing birth weight, being born at 25-27 weeks and being female child.

CONCLUSION

With an active approach in treatment, the outcome of infants born at 25 weeks is comparable to those born at 26-27 weeks. Thus, the 'grey zone' in which the risk of adverse outcome is high narrows to 22-24 weeks.

Prophylactic or early selective surfactant combined with nCPAP in very preterm infants

OBJECTIVE

Early surfactant followed by extubation to nasal continuous positive airway pressure (nCPAP) compared with later surfactant and mechanical ventilation (MV) reduce the need for MV, air leaks, and bronchopulmonary dysplasia. This randomized, controlled trial investigated whether prophylactic surfactant followed by nCPAP compared with early nCPAP application with early selective surfactant would reduce the need for MV in the first 5 days of life.

METHODS

A total of 208 inborn infants who were born at 25 to 28 weeks' gestation and were not intubated at birth were randomly assigned to prophylactic surfactant or nCPAP within 30 minutes of birth. Outcomes were assessed within the first 5 days of life and until death or discharge of the infants from hospital.

RESULTS

Thirty-three (31.4%) infants in the prophylactic surfactant group needed MV in the first 5 days of life compared with 34 (33.0%) in the nCPAP group (risk ratio: 0.95 [95% confidence interval: 0.64-1.41]; P = .80). Death and type of survival at 28 days of life and 36 weeks' postmenstrual age and incidence of main morbidities of prematurity (secondary outcomes) were similar in the 2 groups. A total of 78.1% of infants in the prophylactic surfactant group and 78.6% in the nCPAP group survived in room air at 36 weeks' postmenstrual age.

CONCLUSIONS

Prophylactic surfactant was not superior to nCPAP and early selective surfactant in decreasing the need for MV in the first 5 days of life and the incidence of main morbidities of prematurity in spontaneously breathing very preterm infants on nCPAP.

European consensus guidelines on the management of neonatal respiratory distress syndrome in preterm infants - 2010 update

Despite recent advances in the perinatal management of neonatal respiratory distress syndrome (RDS), controversies still exist. We report the updated recommendations of a European panel of expert neonatologists who had developed consensus guidelines after critical examination of the most up-to-date evidence in 2007. These updated guidelines are based upon published evidence up to the end of 2009. Strong evidence exists for the role of a single course of antenatal steroids in RDS prevention, but the potential benefit and long-term safety of repeated courses are unclear. Many practices involved in preterm neonatal stabilisation at birth are not evidence-based, including oxygen administration and positive pressure lung inflation, and they may at times be harmful. Surfactant replacement therapy is crucial in the management of RDS, but the best preparation, optimal dose and timing of administration at different gestations is not always clear. Respiratory support in the form of mechanical ventilation may also be lifesaving, but can cause lung injury, and protocols should be directed at avoiding mechanical ventilation where possible by using nasal continuous positive airways pressure or nasal ventilation. For babies with RDS to have best outcomes, it is essential that they have optimal supportive care, including maintenance of a normal body temperature, proper fluid management, good nutritional support, management of the ductus arteriosus and support of the circulation to maintain adequate tissue perfusion.

Activities of respiratory chain complexes and pyruvate dehydrogenase in isolated muscle mitochondria in premature neonates

BACKGROUND AND AIMS

Most diseases in premature neonates are secondary to immaturity of various organ systems. Also the inadequate capacity of mitochondrial energy production may play an important role in the neonatal morbidity.

SUBJECTS AND METHODS

The activities and amount of respiratory chain (RC) complexes, pyruvate dehydrogenase (PDH) and citrate synthase (CS) were analysed in isolated muscle mitochondria obtained at autopsy in 19 premature neonates using spectrophotometric and radioenzymatic methods and blue-native electrophoresis and Western blotting. Two groups of children recommended for muscle biopsy at the age of 0.5-2 and 3-18 years served as controls.

RESULTS

In premature neonates, the activities of RC complexes III, IV, PDH and CS were markedly lower in comparison with older children. On the contrary, the activity of complex I was higher in premature neonates than in older children. The ratios between RC complexes I, II and III and CS were significantly higher in premature neonates in comparison with older children. In addition, the protein amount of RC complexes and PDH subunits were lower in premature neonates in comparison with older children.

CONCLUSION

The results of our study document the age-dependent differences in activities of PDH and respiratory chain complexes in early childhood. Lower functional capacity of mitochondrial energy-providing system in critically ill neonates may be explained by combination of various factors including the delay in maturation of PDH and respiratory chain complexes in very premature neonates and increased degradation of mitochondrial proteins in connection with sepsis, tissue hypoperfusion or hypoxemia.

European consensus guidelines on the management of neonatal respiratory distress syndrome

Despite recent advances in the perinatal management of neonatal respiratory distress syndrome (RDS), controversies still exist. We report the recommendations of a European panel of expert neonatologists who developed consensus guidelines after critical examination of the most up-to-date evidence in 2007. Strong evidence exists for the role of antenatal steroids in RDS prevention, but it is not clear if repeated courses are safe. Many practices involved in preterm neonatal stabilization at birth are not evidence based, including oxygen administration and positive pressure lung inflation, and they may at times be harmful. Surfactant replacement therapy is crucial in management of RDS but the best preparation, optimal dose and timing of administration at different gestations is not always clear. Respiratory support in the form of mechanical ventilation may also be life saving but can cause lung injury, and protocols should be directed to avoiding mechanical ventilation where possible by using nasal continuous positive airways pressure. For babies with RDS to have the best outcome, it is essential that they have optimal supportive care, including maintenance of a normal body temperature, proper fluid management, good nutritional support, management of the ductus arteriosus and support of the circulation to maintain adequate blood pressure.

High-frequency jet ventilation improves gas exchange in extremely immature infants with evolving chronic lung disease

Extremely preterm infants often develop chronic lung disease (CLD) characterized by heterogeneous aeration; poorly supported, floppy airways; and air trapping. High-frequency jet ventilation (HFJV) with high end-expiratory pressure (optimal lung volume strategy [OLVS]) may improve airway patency, lead to better gas distribution, improve gas exchange, and facilitate extubation. In a pilot trial, this study sought to explore the effect of HFJV on oxygenation, ventilation, and ease of extubation in preterm infants with evolving CLD and refractory respiratory failure (RRF). From September 2002 to October 2004, 12 episodes of RRF developed in 10 ventilated extremely immature infants with evolving CLD (10 on conventional and two on high-frequency oscillation). Chorioamnionitis was confirmed in all infants, patent ductus arteriosus was ligated in five patients, and UREAPLASMA UREALYTICUM was cultured from trachea in four patients. HFJV with OLVS was initiated when oxygenation index (OI) > 10 or exhaled tidal volume (V TE) >or= 7 mL/kg were required to maintain partial pressure of carbon dioxide, arterial (Pa CO2) < 60 mm Hg. Inspiratory time (0.02/s) and frequency (310 to 420/min) were set initially with adjustment of pressure amplitude to keep Pa CO2 between 45 and 55 mm Hg. Ventilatory stabilization and weaning from mechanical ventilation with extubation to nasal continuous positive airway pressure (CPAP) were the goals of this approach. Gas exchange data were analyzed by Analysis of variance for repeated measures. Ten patients on 11 occasions of RRF were extubated to nasal CPAP successfully in a median of 15.5 days. Nine of 10 patients survived (one died of pentalogy of Cantrell), all required supplemental O2 at 36 weeks. Pa CO2 decreased within 1 hour after the initiation of HFJV, and OI decreased by 24 hours. Both remained significantly lower until successful extubation ( P < 0.02). Compared with conventional ventilation or high-frequency oscillatory ventilation, HFJV used with OLVS appears to improve gas exchange and may facilitate weaning from mechanical ventilation (MV) in extremely immature infants with evolving CLD. These encouraging pilot data need to be confirmed in a larger clinical trial.

Expired tidal volumes measured by hot-wire anemometer during high-frequency oscillation in preterm infants

We sought to determine the normocapnic values of expiratory tidal volume measured by hot-wire anemometer, and to evaluate how often expiratory tidal volume exceeds estimated anatomical dead space during high-frequency oscillatory ventilation (HFOV) in preterm infants. We also sought to determine the relationship between expiratory tidal volume and other respiratory parameters. The neonatal respiration monitor SLE 2100 VPM, a hot-wire anemometer, was used to measure expired tidal volume (V(T,E)) in patients ventilated by the Sensormedics 3,100A during routine clinical use of HFOV. Two hundred and fourteen simultaneous measurements of PaCO(2), V(T,E), fraction of inspired oxygen (FiO(2)), continuous distending pressure (CDP), frequency, and amplitude were obtained from 28 patients. The median birth weight was 852 g (range, 435-3,450 g), and median gestational age was 27.2 weeks (range, 23.3-41.0 weeks). One hundred and eighteen (55%) normocapnic measurements, 42 (20%) hypocapnic measurements, and 54 (25%) hypercapnic measurements were recorded in which the median V(T,E) was 1.67 ml/kg (95% confidence interval (CI), 1.55-1.79), 1.94 ml/kg (95% CI, 1.74-2.14), and 1.54 ml/kg (95% CI, 1.42-1.66), respectively. The measured V(T,E) exceeded 2.0 ml/kg in 30 instances of normocapnic V(T,E) (14%) and 54 of all V(T,E) (25%), and 3 ml/kg only in 7 (3%) and 11 (5%) instances of normocapnic and all V(T,E). There was a significant difference in median normocapnic V(T,E) obtained when FiO(2) was between 0.21-0.35, compared to values obtained when FiO(2) was 0.36-1.0 (1.61 ml/kg (95% CI, 1.52-1.70) vs. 2.06 ml/kg (95% CI, 1.93-2.19), P < 0.002). The calculated values of PaCO(2) between 35-47, using the calculated regression equation for prediction of PaCO(2) (mmHg), correctly predicted normocapnic values in 60% of measurements. Values >47 should predict hypercapnia in 81% of cases. In conclusion, expired tidal volume measurement by heated double-wire anemometer sensor is feasible, provides useful real-time information about tidal volume changes, and may improve the clinical management of HFOV.

Carnitine concentrations in term and preterm newborns at birth and during the first days of life

Carnitine plays an important role in energetic metabolism. The aim of the study was to characterize the carnitine status in term and preterm newborns with respect to gestational age, birth weight, haematocrit and red blood cell count (RBC). The effect of nutrition on carnitine levels in the first week of life was also studied. Total blood pool of free carnitine (FC), acylcarnitines (AC) and total carnitine (TC) were analysed in whole cord blood and postnatally in capillary blood obtained at the day 4-6 in 33 term newborns and at the day 7-10 in 27 preterm newborns using tandem mass spectrometry. Plasma level of carnitine in the cord blood was measured using radioenzymatic method. Cord plasma levels of FC, AC and TC were higher in preterm newborns in comparison with term newborns (p < 0.01), but the total blood pool of FC and TC in whole cord blood was lower in preterm newborns than in term newborns (p < 0.01) and positive correlation was found between FC and gestational age or birth weight (p < 0.05). In addition, positive correlation was found between AC and red blood cell count or haematocrit (p < 0.05). During the first week of life, blood pool of FC and TC in term newborns and AC and TC in preterm newborns decreased regardless of the type of enteral or parenteral nutrition. Our results indicate that preterm newborns are born with limited carnitine store. Interpretation of carnitine analyses in whole blood relies in addition to gestational age and birth weight on the haematocrit, especially in newborns with anaemia or blood hyperviscosity.

Interaction between surfactant and ventilatory support in newborns with primary surfactant deficiency

The interaction between exogenous surfactant and various modes of ventilatory support in terms of timing, quality and quantity can influence both short- and long-term outcomes of immature infants. Alterations to the pulmonary surfactant system can occur with all forms of mechanical ventilation. Experimental data suggest possible interaction between ventilatory support and exogenous surfactant even during the first breaths in the delivery room. The adverse effect on surfactant function at this time can increase the need for and duration of ventilatory support. The logical approach to ventilatory support is to be minimally aggressive with optimal recruitment of the lungs to avoid ventilator-induced lung injury. Nasal continuous positive airway pressure (CPAP) in combination with early prophylactic surfactant administration may be an effective and less damaging method capable of reducing the need of artificial ventilation, but its benefit has not been proven in extremely preterm infants less than 28 weeks' gestation. Because of unproven efficacy of nasal CPAP in extremely premature infants, the population most at risk for adverse pulmonary and neurologic outcome, this paper focuses on the comparison of conventional and high-frequency oscillatory ventilation (HFOV) with respect to alteration of surfactant function, and short- and long-term outcomes, in both human and experimental trials. Though the two most recent large clinical trials provide reassurance with respect to the safety of first-intention high-frequency ventilation, the reduction in the risk of chronic lung disease appears to be only modest or absent. Recent laboratory investigations suggest that the key element of HFOV, namely optimization of volume, can, under some circumstances, be replicated with low tidal volume conventional ventilation and high positive end-expiratory pressure. Recent introduction of patient-triggered volume-targeted conventional ventilation into clinical practice offers the promise of a practical means of providing gentle conventional ventilation capable of minimizing ventilator-induced lung injury. Ultimately, well-designed comparative clinical trials with long-term outcomes are essential to accurately quantify risks and benefits of any new approach to mechanical ventilation. Without such data, these experimental results should not be extrapolated into clinical practice, because of the multifactorial pathophysiology of the development of chronic pulmonary disease in extremely premature infants and the risk of unanticipated adverse effects.

[Does the decreasing rate of neonatal mortality increase severe neonatal neurosensory morbidity?]

OBJECTIVE

To investigate relation between the mortality and the incidence of serious neonatal neurosensoric morbidity in very low birth weight newborns (VLBWN, birth weigh < or = 1499 g) during the three periods as defined by different quality of the parinatal and neonatal care.

DESIGN

Retrospective analysis.

SETTING

Perinatal center of the General Faculty Hospital. 1st Medical Faculty Charles University, Prague.

SUBJECT AND METHODS

All live-born VLBWN in 1987-2001 were divided according to their birth-date to three five-year periods characterized by different quality of the perinatal and neonatal care. Ist period 1987-1991: the presurfactant area with no standard use of antenatal steroids and without defined border of the fetus viability; IInd period 1992-1996: the transient aera; IIIrd period 1997-2001: the surfactant aera with standard use of the antenatal steroids, and defined border of the fetus viability. VLBWN were divided according to birth weight to three subgroups (p. h. < 750 g, p. h. = 750-999 g, p. h. = 1000-1499 g). Mortality was defined by a death in our department until the discharge. VLBW newborns classified as newborns with serious neonatal neurosensoric morbidity (NNsM) had to have one of the following diagnoses at least: severe intraventricular haemorrhage (IVH gr. 3-4), posthemorhagic hydrocephaly (PHH), cystic periventricular leukomalacia (cPVL), meningitis, ventriculitis, encephalitis (M/E), retinopathy of prematurity > or = stage III (ROP > or = III st.). The chi 2 test was used for statistic evaluation.

RESULTS

There were 873 VLBWN born and 208 of them died in the whole period (1987-2001). Mortality decreased in 5 year periods gradually: 1st period 111/226 (49%); IInd period 55/217 (25%); IIIrd period 42/430 (10%). The decrease of mortality was significant in all weight categories (p < 0.001). The incidence of NNsM was evaluated in 612 newborns and was similar in all periods regarding weight subcategories < 1000 g, but decreased significantly in the weight category 1000-1499 g (14/215 (6%) vs 13/73 (18%), p < 0.01).

CONCLUSION

Improvement in survival of extremely low birth-weight infants did not increase the incidence of serious neurosensoric morbidity and evenmore NNsM was reduced in haevier very premature newborns during the nineties.

Induction of uncoupling protein 3 gene expression in skeletal muscle of preterm newborns

Prematurity is associated with delayed postnatal activation of mitochondrial oxidative phosphorylation and impaired switch from glycolytic to oxidative metabolism. Fatty acids (FA), which represent a major energy substrate in mature muscle cells, are engaged in the postnatal activation of genes of energy metabolism and lipid oxidation. To understand the mechanism activating mitochondria in human newborns, expression of the genes for mitochondrial uncoupling proteins (UCP) was characterized in autopsy samples of skeletal (n = 28) and cardiac (n = 13) muscles of preterm neonates, who mostly died during the first postnatal month, and two aborted fetuses. Transcripts levels for UCP2, UCP3, and also for genes engaged in the transport of FA between cytoplasm and mitochondria were measured using real-time reverse transcriptase PCR. In accordance with studies in mice, our results document postnatal induction of UCP3 gene expression in skeletal muscle, involvement of nutritional FA in the induction, and a role of UCP3 in mitochondrial FA oxidation. They suggest impaired postnatal activation of UCP3 gene in neonates delivered before approximately 26 wk of gestation. Mean levels of the UCP3 transcript in skeletal muscle were by two orders of magnitude higher than in the heart. In contrast to UCP3, the UCP2 gene was active in fetuses, and its expression was not affected by nutrition. Our results support a role of UCP3 in postnatal activation of lipid oxidation in skeletal muscle and suggest the involvement of UCP3 in the delayed activation of mitochondrial energy conversion in very immature preterm neonates.

Mitochondrial energy metabolism in very premature neonates

The activity, amount and protein composition of pyruvate dehydrogenase (PDH) and respiratory chain complexes were studied in muscle mitochondria obtained postmortally from 6 neonates with a gestational age of 23-29 weeks. The activities of PDH and respiratory chain complex III and IV and citrate synthase were significantly lower in comparison with control children aged 0.5-2 and 2-20 years. Protein analyses revealed a parallel decrease in the content of PDH, respiratory chain complexes and their subunits in the cases analyzed. The observed immaturity of the mitochondrial energy-providing system suggests that significant development of mitochondrial energy metabolism occurs during the last 3 months of prenatal development. The metabolic disturbances of mitochondrial energy conversion associated with the low functional capacity and content of PDH and respiratory chain complexes may play an important role in the morbidity of very premature neonates.

Early versus delayed surfactant administration in extremely premature neonates with respiratory distress syndrome ventilated by high-frequency oscillatory ventilation

OBJECTIVE

To determine whether early surfactant administration is superior to selective delayed treatment in terms of improving survival and/or reducing chronic lung disease in extremely premature neonates with respiratory distress syndrome (RDS) treated by high-frequency oscillatory ventilation (HFOV).

DESIGN

Prospective randomized clinical trial.

SETTING

Tertiary neonatal intensive care unit (NICU) in the Perinatology Center of Prague.

PATIENTS

Forty-three extremely premature infants who needed artificial ventilation within 3 h after delivery.

INTERVENTIONS

Patients were randomly assigned to either early ( n=21) or delayed (n=22) administration of surfactant. All were ventilated by HFOV as the primary mode of ventilation using the high volume strategy aimed at optimizing lung volume. Curosurf at a dose of 100 mg/kg was given as a single bolus via the endotracheal tube within 1 min immediately after intubation in the early group (EARL), or during HFOV only when defined criteria were reached in the delayed (DEL) group.

MEASUREMENTS AND RESULTS

No differences were noted in demographic data between the two groups. Fewer infants randomized to the EARL group required oxygen use or died at 36 weeks (combined outcome 29% vs 64%, p=0.021), and there was a lower incidence of any intraventricular hemorrhage in this group (43 vs 82%, p=0.008).

CONCLUSIONS

When compared to delayed dosing, early administration of surfactant followed by HFOV facilitates and accelerates respiratory stabilization during the acute phase of severe RDS, may reduce the incidence of chronic lung disease or death and may positively influence the incidence of severe intracranial pathology in extremely premature infants with primary surfactant insufficiency.

Fast decline of hematopoiesis and uncoupling protein 2 content in human liver after birth: location of the protein in Kupffer cells

Hepatic hematopoiesis is prominent during fetal life and ceases around birth. In rodent liver, the decline of the hepatic hematopoiesis starts abruptly at birth being accompanied by a decrease of mitochondrial uncoupling protein 2 (UCP2) expression in monocytes/macrophages, whereas hepatocytes may express UCP2 only under pathologic situations. The goals of this study were to characterize hepatic hematopoiesis in humans around birth, and to identify cells expressing UCP2. Hematopoiesis was evaluated histologically in the liver of 22 newborns (mostly very premature neonates), who died between 45 min and 140 d after birth, and one fetus. UCP2 expression was characterized by Northern blots, immunoblotting, immunohistochemistry, and by in situ hybridization. The number of hematopoietic cells started to decrease rapidly at birth, irrespectively of the gestational age (23-40 wk) of neonates. A similar decline was observed for UCP2 expression, which was relatively high in fetal liver. UCP2 was detected only in myeloid cells (mainly in Kupffer cells), but not in hepatocytes, although sepsis or other pathologies occurred in the critically ill newborns. Kupffer cells represent the major site of mitochondrial UCP2 expression in the human newborn. UCP2 may be essential for the differentiation and function of macrophages and serve as a marker for these cells in human liver during the perinatal period.

Recurrent ACTH-independent Cushing's syndrome in multiple pregnancies and its treatment with metyrapone

A 17-year-old primigravid woman presented with Cushing's syndrome. Typical clinical symptoms and signs developed at the beginning of pregnancy. By week 17 of gestation, plasma cortisol diurnal rhythm was absent and there was a paradoxical increase in plasma cortisol after a 1-mg dexamethasone overnight suppression test. Basal urinary free cortisol was 10 times above the upper limit (in pregnancy) and ACTH levels were suppressed. The diagnosis of ACTH--independent Cushing's syndrome was established. MRI scans revealed normal adrenal and pituitary glands. To control hypercortisolism, the patient was treated with metyrapone. At 34 weeks of gestation, the patient developed preeclampsia and underwent caesarean section. A female infant weighing 1070 g was delivered. No apparent metyrapone-induced teratogenic effects were observed. Cushing's syndrome in the patient resolved within three weeks of delivery. No corticosteroid replacement therapy either for child or mother was needed. Eight months after delivery the patient became pregnant again and rapidly developed Cushing's syndrome with typical clinical symptoms and signs and laboratory results (urinary free cortisol 6464 nmol/24 h). This second pregnancy was unwanted and terminated by artificial abortion that was followed by rapid resolution of hypercortisolism. A third pregnancy, 12 months after delivery was also accompanied by the rapid development of hypercortisolism which recovered after artificial termination. The mechanisms by which pregnancy-induced Cushing's syndrome occurred in this patient are unclear. Aberrant responsiveness or hyperresponsiveness of adrenocortical cells to a non-ACTH and non-CRH substance produced in excess in pregnancy should be considered. Metyrapone suppression of hypercortisolism currently represents the best treatment for these rare cases.

[Neonatal mortality in the Czech Republic 1998-1999]

OBJECTIVE

To evaluate neonatal mortality rate (NMR) in 1998 and 1999 years in the Czech Republic.

DESIGN

Retrospective epidemiological study of all alive newborns born in 1998 and 1999 in the Czech Republic.

SETTINGS

12 perinatological centers of nine regions of Bohemia and Moravia.

METHODS

All alive, died, died with congenital defects newborns were registered and results of neonatal mortality rate and specific neonatal mortality rate were calculated. The main causes of death were divided into four groups (intraventricular hemorrhage grade III-IV, infection, acute respiratory failure and others) and evaluated comparatively. In 1999 the NMR of newborns with birth weight below 500 g and their survival were introduced for the first time in the Czech Republic.

RESULTS

The fluent decrease of NMR during nineties was stopped in 1999. Increase of NMR from 2.8@1000 in 1998 to 3.0@1000 in 1999 was mainly caused by arise of specific neonatal mortality rate in newborns weighing > or = 2000 g. Comparing 1998 and 1999 years, two times more these newborns without serious congenital defects died in 1999 (28 vs. 56). Specific neonatal mortality rate of extremely low birth weight newborns further decreased (359@1000 vs. 279@1000) especially in the newborns with birth weight between 500-749 g (543@1000 vs. 373@1000). The most frequent main causes of death still has been intraventicular haemorrhage grade III-IV and infection in very low birth weight newborns, and serious congenital defects and infection in newborns weighing > or = 1500 g. The concentration of very low birth weight newborns to perinatological centers by transfer in uterus was 81% in 1998 and 83% in 1999. The differences in neonatal mortality rates between nine regions of Bohemia and Moravia has been getting equal but has been still great in specific neonatal mortality rate of extremely low birth weight newborns between the best and worst regions (147@1000 vs. 458@1000). There were registered 19 newborns weighing < or = 500 g surviving more than 24 hours after delivery in the Czech republic. Specific neonatal mortality rate of these newborns was 316@1000 and 527@1000 survived.

CONCLUSION

Reserves for further lowering of NMR are improving the care after extremely low birth weight newborns in the regions with below average results and decreasing the mortality of newborns with birth weight > or = 2000 g by introducing of group B streptococcus prophylaxis, improving prenatal diagnostics of serious congenital defects and early and more quality postnatal transport of newborns suffered from acute respiratory failure to centers disposing of the latest methods of treatment.

[Complications of prevention and treatment of erythrocyte alloimmunization (case reports)]

OBJECTIVES

The treatment of late recognized alloimunization with intraumbilical transfusions is more difficult and more often connected with complications.

MATERIAL AND METHOD

Between 1991-1997 we performed 70 intraumbilical transfusions in 25 fetuses for erythrocyte alloimunization. Six fetuses (24%) were hydropic in the beginning of the treatment. Eleven fetuses were delivered before 36 weeks of pregnancy. Two immature neonates (660 g and 1320 g) had intraventricular hemorrhage with neurologic complications. In six cases the transfusion was complicated by severe bradycardia of the fetus, but only twice the pregnancy was to be terminated by cesarean sectio during 24 hours after the procedure. Two of the 25 fetuses died antenataly and one postnataly, all of them primary hydropic. Two neonates had severe late onset anemia.

CONCLUSION

Fetal alloimune anemia should be treated before onset of hydrops. The study was supported by the grant of IGA Ministry of Health CR No. 3200-3.