Resuscitation and ventilation strategies for extremely preterm infants: a comparison study between two neonatal centers in Boston and Stockholm

Management of bronchopulmonary dysplasia in Japan: A nationwide survey

BACKGROUND

The incidence of bronchopulmonary dysplasia (BPD) and respiratory management practices for extremely low birth weight infants (ELBWIs) widely vary among institutions and countries.

AIMS

To clarify the variation and characteristics of the current practices of Japanese neonatologists managing patients with BPD.

STUDY DESIGN

Questionnaire-based survey.

PARTICIPANTS

Level II and III perinatal centers certified by the Japan Society of Perinatal and Neonatal Medicine.

OUTCOME MEASURES

Policies of the neonatal intensive care units (NICUs) regarding respiratory care and medications for BPD prevention and treatment.

RESULTS

A total of 76 % of facilities (207/274) responded to our survey. The response rates of level III and II facilities were 91 % (102/112) and 35 % (105/296), respectively. INtubation-SURfactant-Extubation and Less Invasive Surfactant Administration methods were performed in 23 % (47/206) and 1 % (3/206) of facilities, respectively. For the prophylactic purpose, systemic and inhaled steroids were administered "frequently" or "occasionally" in 14 % (28/205) and 42 % (86/204) of NICUs, respectively. For the therapeutic purpose, systemic and inhaled steroids were administered "frequently" or "occasionally" in 84 % (171/204) and 29 % (59/204) of NICUs, respectively. Approximately half of the NICUs (99/202) used volume-targeted ventilation (VTV) "frequently" or "occasionally" in progressing BPD. High-frequency oscillation ventilation (HFOV) was used for progressing BPD "frequently" and "occasionally" in 89 % (180/202) of the facilities.

CONCLUSIONS

Our study provided an overview and characteristics of BPD management in Japan in recent years. Noninvasive approaches with surfactant administration remain not widely used in Japan. HFOV is a widely accepted management for progressing BPD.

Respiratory management and bronchopulmonary dysplasia in extremely preterm infants: a comparison of practice between centres in Oxford and Melbourne

OBJECTIVE

Considerable variation in the care of extremely low gestational age infants (ELGAN) contributes to the variation in incidence of bronchopulmonary dysplasia (BPD). We compared management and outcomes of two neonatal centres with different respiratory support strategies.

STUDY DESIGN

Retrospective cohort study of infants <28 weeks gestational age treated at two units in Australia and the UK between 2015 and 2017.

RESULT

Of 492 infants, the overall incidence of BPD for extremely preterm infants was 62.20% and was similar across both sites (64.84% at Monash vs. 60.65% at Oxford). Independent predictors for the development of BPD or mortality included the days on mechanical ventilation (MV, adjusted OR 1.13, 95% Cl 1.07-1.19) and use of inhaled nitric oxide (adjusted OR 13.42, 95% Cl 1.75-103.28).

CONCLUSION

Primary choice of non-invasive respiratory support had no significant impact on BPD development. Duration of MV and using nitric oxide were independent predictors for death or BPD.

Global incidence of intraventricular hemorrhage among extremely preterm infants: a systematic literature review

OBJECTIVES

To conduct a systematic literature review to evaluate the global incidence of intraventricular hemorrhage grade 2-4 among extremely preterm infants.

METHODS

We performed searches in MEDLINE and Embase for intraventricular hemorrhage and prematurity cited in English language observational studies published from May 2006 to October 2017. Included studies analyzed data from infants born at ≤28 weeks' gestational age and reported on intraventricular hemorrhage epidemiology.

RESULTS

Ninety-eight eligible studies encompassed 39 articles from Europe, 31 from North America, 25 from Asia, five from Oceania, and none from Africa or South America; both Europe and North America were included in two publications. The reported global incidence range of intraventricular hemorrhage grade 3-4 was 5-52% (Europe: 5-52%; North America: 8-22%; Asia: 5-36%; Oceania: 8-13%). When only population-based studies were included, the incidence range of intraventricular hemorrhage grade 3-4 was 6-22%. The incidence range of intraventricular hemorrhage grade 2 was infrequently documented and ranged from 5-19% (including population-based studies). The incidence of intraventricular hemorrhage was generally inversely related to gestational age.

CONCLUSIONS

Intraventricular hemorrhage is a frequent complication of extremely preterm birth. Intraventricular hemorrhage incidence range varies by region, and the global incidence of intraventricular hemorrhage grade 2 is not well documented.

Variations in preterm stabilisation practices and caffeine therapy between two European tertiary level neonatal units

AIM

To investigate interinstitutional differences in preterm infant stabilisation between two European tertiary neonatal centres with particular focus on intubation timing, surfactant administration, caffeine therapy and neonatal morbidity and mortality.

METHODS

Retrospective (2012-2014) study of very low birth weight (VLBW) preterm infants admitted to John Radcliffe Hospital (UK centre) and Charité Medical Centre (German centre). Timing of intubation, surfactant and caffeine administration and respiratory outcomes were examined.

RESULTS

Gestational age, birth weight and five-minute Apgar scores of VLBW infants from the UK centre (n = 86) were comparable to those from the German centre (n = 96). Significant differences in antenatal steroid therapy, intubation timing and surfactant therapy were noted. Timing of caffeine initiation differed significantly between centres (median 0 [0-2.5] UK vs. 2 [1.5-4] days German centre); however, caffeine was discontinued at a similar corrected gestational age of 34.7 weeks. Mechanical ventilation was significantly longer at the UK centre, but there was no difference in bronchopulmonary dysplasia (BPD) (44% UK vs. 36% German centre) or mortality (15% UK vs. 13% German centre).

CONCLUSION

Timing of primary intubation and caffeine therapy differed significantly between centres. However, earlier intubation and caffeine administration in the UK centre were not associated with a changed incidence of BPD.

Methods of surfactant administration and early ventilation in neonatal intensive care units in New South Wales and the Australian Capital Territory

BACKGROUND

This study investigates trends in methods of surfactant administration and early respiratory management in neonatal intensive care units [NICU] in New South Wales [NSW] and the Australian Capital Territory [ACT] in 2015 and evaluate whether differences in practice translate to variances in short term outcomes.

METHODS

Surveys were sent to NICUs in NSW and ACT to ascertain their practice of surfactant administration and respiratory management. A retrospective data analysis with data from the NICUS database from 01/01/2013-30/06/2015 was performed. Included were all patients that received Surfactant, were inborn, without major malformation, ≥24 weeks gestational age [GA] and birthweight ≥500 g. Major respiratory outcome measures were time ventilated, air leak, oxygen requirement at 36 weeks corrected gestational age [cGA], home oxygen therapy after discharge and retinopathy of prematurity [ROP]. Along with this data demographic and morbidity data was also obtained for comparison [mortality, necrotizing enterocolitis [NEC], persistent ductus arteriosus [PDA], intraventricular hemorrhage [IVH].

RESULTS

1453 patients met inclusion criteria. Patient data comparing major respiratory outcomes showed patients receiving less invasive Surfactant therapy and respiratory management spent longer time on CPAP [559 vs. 407 hrs, p = 0.01] and in the older gestation subgroups less time on mechanical ventilation [18 vs. 50 hrs p = <0.001] and were discharged earlier [48 vs. 54 days, p = 0.03]. There was however, higher rates of oxygen requirement at 36 weeks cGA [33 vs. 26.3% p = 0.01] and a higher proportion of home oxygen in this patient group [11.3 vs. 7.1% p = 0.03]. Major morbidity outcome data showed no significant differences.

CONCLUSIONS

Less invasive Surfactant therapy and gentle early respiratory management should be considered as a viable alternative to established methods of surfactant administration and ventilation.

Effect of high-frequency oscillation on pressure delivered by high flow nasal cannula in a premature infant lung model

OBJECTIVE

This study describes the effect of high-frequency oscillation on airway pressure generated by high flow nasal cannula (HFNC) in a premature infant lung model.

DESIGN/METHODS

A premature in 0.5 or 1.0 mL/cmH ₂ O, respiratory rate (RR) of 40 or 60 breaths per min, and tidal volume of 6 mL. Oscillation was achieved by passing the HFNC supply flow through a 3-way solenoid valve operating at 4, 6, 8, or 10 Hz. Airway pressure at the simulated trachea was recorded following equilibration of end-tidal CO ₂ both with and without oscillation.

RESULTS

Superimposing high-frequency oscillations onto HFNC resulted in an average decrease in mean airway pressure of 17.9% (P = .011). The difference between the maximum and minimum airway pressures, ∆ P _min-max, significantly increased as oscillation frequency decreased ( P < .001). Airway pressure during oscillation was 12.8% greater with the 1.0 vs the 0.5 mL/cmH ₂ O compliance at flows > 4 L/min ( P = .031). CO ₂ clearance was 13.1% greater with the 1.0 vs 0.5 mL/cmH ₂ O compliance at oscillation frequencies less than 8 Hz ( P = .015).

CONCLUSION

In this in-vitro study we demonstrate that delivered mean airway pressure decreases when applying high-frequency oscillation to HFNC, while still improving CO₂ clearance. The combination of improved CO ₂ clearance and reduced pressure delivery of this novel noninvasive modality may prove to be a useful improvement in the respiratory care of infants in respiratory distress.

Global incidence of bronchopulmonary dysplasia among extremely preterm infants: a systematic literature review

BACKGROUND

Infants born extremely preterm (<28 weeks gestational age (GA)) face a high risk of neonatal mortality. Bronchopulmonary dysplasia (BPD) is the most common morbidity of prematurity.

OBJECTIVE

To evaluate the global incidence of BPD among infants born extremely preterm.

DESIGN

A systematic review of the literature was conducted in Embase and MEDLINE (via PubMed) using a prespecified search strategy for BPD and prematurity. Observational studies published in English between 16 May 2006 and 16 October 2017 reporting on the occurrence of BPD in infants born <28 weeks GA were included.

RESULTS

Literature searches yielded 103 eligible studies encompassing 37 publications from Europe, 38 publications from North America, two publications from Europe and North America, 19 publications from Asia, one publication from Asia and North America, six publications from Oceania, and zero publications from Africa or South America. The reported global incidence range of BPD was 10-89% (10-73% in Europe, 18-89% in North America, 18-82% in Asia, and 30-62% in Oceania). When only population-based observational studies that defined BPD as requiring supplemental oxygen at 36 weeks postmenstrual age were included, the global incidence range of BPD was 17-75%. The wide range of incidences reflected interstudy differences in GA (which was inversely related to BPD incidence), birthweight, and survival rates across populations and institutions.

CONCLUSIONS

BPD is a common health morbidity occurring with extremely preterm birth. Further study of factors that impact incidence, aside from low GA, may help to elucidate modifiable risks.

Improving Respiratory Support Practices to Reduce Chronic Lung Disease in Premature Infants

Supplemental Digital Content is available in the text.

Introduction:

We implemented a bundle of respiratory care practices and optimized delivery of continuous positive airway pressure (CPAP) to reduce the incidence of chronic lung disease (CLD) among very low birth weight (VLBW) infants born before 33 weeks gestation.

Methods:

Our multidisciplinary task force utilized 6 plan-do-study-act cycles to test our interventions. The primary outcome was the quarterly percentage of infants diagnosed with CLD; other outcomes included the percentage of infants initially managed with CPAP, intubation <72 hours of age, use of a nasal cannula, and days of ventilation, oxygen, and/or CPAP. Process measures included compliance with each of the 5 components of the bundle; balancing measures included mortality and complications of prematurity.

Results:

Demographics were similar in the 55 infants born before and 76 infants born after the task force interventions, except for gestational age, which was lower before. CLD decreased by 55.5% (from 37.5% to 16.7%). Quarterly percentage of infants requiring intubation decreased from 87.5% to 40.8%. Quarterly average days of ventilation decreased from 11.2 to 6.1, and days of supplemental oxygen declined from 44.1 to 25.4, while the use of CPAP increased. There were no differences in adverse events including mortality, pneumothorax, use of postnatal steroids, or any retinopathy of prematurity. The incidence of patent ductus arteriosus declined from 60% to 33% (P < 0.01).

Conclusions:

We reduced the incidence of CLD among our very low birth weight infants born before 33 weeks gestation by over 50% without increasing any measured adverse outcomes. The incidence of patent ductus arteriosus declined.

Pulmonary mechanics measurements by respiratory inductive plethysmography and esophageal manometry: Methodology for infants on non-invasive respiratory support

BACKGROUND

Infants are commonly supported with non-invasive ventilation (NIV) such as nasal CPAP and high flow nasal cannula (HFNC). These modes utilize a nasal/oral interface precluding use of a traditional airway flow sensor, such as a pneumotachometer (PNT), needed for pulmonary mechanics (PM) measurements. Respiratory Inductive Plethysmography (RIP), when properly calibrated, records tidal volume non-invasively from chest wall movements. Our aim was to integrate RIP into an existing neonatal pulmonary function testing system to measure PM in infants on NIV and to compare measurements of dynamic lung compliance (CL) and resistance (RL) using RIP with those obtained using a PNT.

DESIGN/METHODS

RIP ribcage (RC) and abdominal (ABD) signals were recorded simultaneously with the flow signal from a PNT; transpulmonary pressure was estimated using an esophageal catheter. Two calibration algorithms were applied to obtain RC and ABD scaling factors.

RESULTS

Forty PM measurements were performed on 25 infants (GA 31.5±2.9 weeks; birth weight 1598±510 g; median age 7 days). Correlation coefficients for RIP- vs. PNT-based PM were r2 = 0.987 for CL and r2 = 0.997 for RL. From Bland-Altman analysis, the mean bias (±95% CI) between RIP and PNT methods was -0.004±0.021 ml/cmH2O/kg for CL and 0.7±2.9 cmH2O/(L/sec) for RL. The upper, lower limits of agreement (±95% CI) were 0.128±0.037, -0.135±0.037 ml/cmH2O/kg for CL and 18.6±5.1, -17.2±5.1 cmH2O/(L/sec) for RL.

CONCLUSION

Properly calibrated RIP may be a useful tool with sufficient diagnostic accuracy for PM measurements without need for a nasal/oral airflow sensor in infants receiving NIV.

Carbon dioxide washout during high flow nasal cannula versus nasal CPAP support: An in vitro study

OBJECTIVE

To compare CO₂ washout time at different levels of HFNC versus NCPAP in a premature infant lung model with simulated mouth-closed and mouth-open conditions using two sizes of nasal cannula and full- and half-prong HFNC insertion depths.

DESIGN/METHODS

A piston-cylinder lung simulator, having a fixed volume of 30 ml and a 4.8 ml dead space, simulated spontaneous breathing (6.5 ml tidal volume, 50 br/min, Ti = 0.5 sec). Two Fisher & Paykel™ cannulas (Fisher & Paykel Healthcare Ltd., Auckland, New Zealand) (2.8 and 3.2 mm O.D.) and two Infant-Flow™ (CareFusion, Yorba Linda, CA) NCPAP cannulas (3.4 and 4.1 mm O.D.) were applied to simulated airways having either 3.5 or 4.5 mm I.D. nares. Simulated mouth opening was a 5 mm I.D. side tap below the nasal interface. The lung was primed with 5% CO₂ . Washout times were determined at HFNC settings of 3, 4, 5, 6, and 8 L/min and NCPAP at 3, 4, 5, 6, and 8 cm H₂ O with simulated open and closed-mouth conditions and full- and half-inserted HFNC prongs.

RESULTS

Overall combined mean washout times for NCPAP with mouth-closed were significantly longer than HFNC over all five pressure and flow device settings by 16.2% (P < 0.001). CO₂ washout times decreased as flow or pressure device settings were increased. There were negligible differences in washout times between NCPAP and HFNC with mouth-open. Mouth-open washout times were significantly less than mouth-closed for all conditions. Overall closed-mouth washout times for HFNC half-prong insertion were longer than for full-prong insertion by 5.3% (P < 0.022).

CONCLUSIONS

Significantly improved CO₂ elimination using HFNC versus NCPAP should be a particularly important consideration in premature infants having very high dead space-to-tidal volume ratio compared to larger infants. Pediatr Pulmonol. 2017;52:792-798. © 2017 Wiley Periodicals, Inc.

Early inhaled nitric oxide in preterm infants <34 weeks with evolving bronchopulmonary dysplasia

OBJECTIVE

To investigate whether early treatment with inhaled nitric oxide (iNO) could prevent bronchopulmonary dysplasia (BPD) in very preterm infants.

STUDY DESIGN

A non-randomized, controlled trial was conducted prospectively in 27 neonatal intensive care units over 12 months. Preterm infants with gestational age <34 weeks and after 7 days of life, who received invasive mechanical ventilation (MV) or nasal continuous positive airway pressure for >2 days, were treated either with low-dose iNO (from 5 as initial dose to 2 parts per million as maintenance dose for ⩾7 days, n=162) or as non-placebo control (n=240). Primary outcome was the incidence of moderate-to-severe BPD at 36 weeks postmenstrual age and/or death before discharge. Secondary outcomes were major complications.

RESULTS

iNO was started on average on day 19 of life (median duration 18 days, range 7 to 55 days). Rate of survival without BPD was significantly lower in the iNO than in the control group, whereas overall rates of BPD, death and major complications were similar between the two groups. Infants who started MV and iNO on postnatal days 15 to 21 had significantly increased survival without BPD (47.6% vs 17.1%, P=0.03, relative risk 2.7, 95% confidence interval 1.1 to 6.5). Additionally, pooled data from both groups showed that rates of perinatal co-morbidities and postnatal complications were higher in BPD infants than in non-BPD infants. The overall incidence of BPD was 55.6% and 75.9% for birth weight <1500 and <1000 g, respectively, or 1.6% for the total population <34 weeks of gestation admitted through the network.

CONCLUSION

Treatment with low-dose iNO did not decrease the overall risk of BPD and death nor showed adverse effects in short-term morbidities among very preterm infants. The benefit of delayed iNO treatment on BPD warrants further studies.

Factors influencing delivered mean airway pressure during nasal CPAP with the RAM cannula

OBJECTIVE

To measure mean airway pressure (MAP) delivered through the RAM Cannula® when used with a ventilator in CPAP mode as a function of percent nares occlusion in a simulated nasal interface/test lung model and to compare the results to MAPs using a nasal continuous positive airway pressure (NCPAP) interface with nares fully occluded.

STUDY DESIGN

An artificial airway model was connected to a spontaneous breathing lung model in which MAP was measured at set NCPAP levels between 4 and 8 cmH2 O provided by a Dräger Evita XL® ventilator and delivered through three sizes of RAM cannulae. Measurements were performed with varying leakage at the nasal interface by decreasing occlusion from 100% to 29%, half-way prong insertion, and simulated mouth leakage. Comparison measurements were made using the Dräger BabyFlow® NCPAP interface with a full nasal seal.

RESULTS

With simulated mouth closed, the Dräger interface delivered MAPs within 0.5 cmH2 O of set CPAP levels. For the RAM cannula, with 60-80% nares occlusion, overall delivered MAPs were 60 ± 17% less than set CPAP levels (P < 0.001). Further, MAP decreased progressively with decreasing percent nares occlusion. The simulated open mouth condition resulted in significantly lower MAPs to <1.7 cmH2 O. The one-half prong insertion depth condition, with closed mouth, yielded MAPs approximately 35 ± 9% less than full insertion pressures (P < 0.001).

CONCLUSIONS

In our bench tests, the RAM interface connected to a ventilator in NCPAP mode failed to deliver set CPAP levels when applied using the manufacturer recommended 60-80% nares occlusion, even with closed mouth and full nasal prong insertion conditions.

The International Network for Evaluating Outcomes of very low birth weight, very preterm neonates (iNeo): a protocol for collaborative comparisons of international health services for quality improvement in neonatal care

BACKGROUND

The International Network for Evaluating Outcomes in Neonates (iNeo) is a collaboration of population-based national neonatal networks including Australia and New Zealand, Canada, Israel, Japan, Spain, Sweden, Switzerland, and the UK. The aim of iNeo is to provide a platform for comparative evaluation of outcomes of very preterm and very low birth weight neonates at the national, site, and individual level to generate evidence for improvement of outcomes in these infants.

METHODS/DESIGN

Individual-level data from each iNeo network will be used for comparative analysis of neonatal outcomes between networks. Variations in outcomes will be identified and disseminated to generate hypotheses regarding factors impacting outcome variation. Detailed information on physical and environmental factors, human and resource factors, and processes of care will be collected from network sites, and tested for association with neonatal outcomes. Subsequently, changes in identified practices that may influence the variations in outcomes will be implemented and evaluated using quality improvement methods.

DISCUSSION

The evidence obtained using the iNeo platform will enable clinical teams from member networks to identify, implement, and evaluate practice and service provision changes aimed at improving the care and outcomes of very low birth weight and very preterm infants within their respective countries. The knowledge generated will be available worldwide with a likely global impact.

Incidence and risk factors for retinopathy of prematurity in a Brazilian reference service

CONTEXT AND OBJECTIVE

Retinopathy of prematurity (ROP) is a known cause of blindness in which diagnosis and timely treatment can prevent serious harm to the child. This study aimed to evaluate the incidence of ROP and its association with known risk factors.

DESIGN AND SETTING

Longitudinal incidence study in the neonatal intensive care unit (NICU) of Universidade Estadual de Montes Claros.

METHODS

Newborns admitted to the NICU with gestational age less than 32 weeks and/or birth weight less than 1,500 grams, were followed up over a two-year period. The assessment and diagnosis of ROP were defined in accordance with a national protocol. The chi-square test or Fisher's exact test were used to determine associations between independent variables and ROP. Analysis on the independent effect of the variables on the results was performed using multiple logistic regression.

RESULTS

The incidence of ROP was 44.5% (95% confidence interval, CI = 35.6-46.1) in the study population. The risk factors associated with the risk of developing the disease were: birth weight less than 1,000 grams (odds ratio, OR = 4.14; 95% CI = 1.34-12.77); gestational age less than 30 weeks (OR = 6.69; 95% CI = 2.10-21.31); use of blood derivatives (OR = 4.14; 95% CI = 2.99-8.99); and presence of sepsis (OR = 1.99; 95% CI = 1.45-2.40).

CONCLUSIONS

The incidence of ROP was higher than that found in the literature. The main risk factors were related to extreme prematurity.

[Variables determining the amount of care for very preterm neonates: the concept of medical stance]

OBJECTIVE

To compare the amount of medical interventions on very preterm neonates (24-31 weeks of gestation) in two French university tertiary care centers, one of which is involved in a Neonatal Developmental Care program. A secondary objective is to assess whether this difference in medical interventions can be linked to a difference in mortality and morbidity rates.

METHODS

We prospectively included all very preterm neonates free from lethal malformation born live in these two centers between 2006 and 2010. These inclusion criteria were met by 1286 patients, for whom we compared the rate of five selected medical interventions: birth by caesarean section, chest intubation in the delivery room, surfactant therapy, pharmacological treatment of patent ductus arteriosus, and red blood cell transfusion.

RESULTS

The rates of the five medical interventions were systematically lower in the center that is involved in Neonatal Developmental Care. There was no significant difference in survival at discharge with no severe cerebral ultrasound scan abnormalities between the two centers. There were, however, significantly higher rates of bronchopulmonary dysplasia and nosocomial sepsis and longer hospital stays when the patients were not involved in a Neonatal Developmental Care program.

DISCUSSION

This benchmarking study shows that in France, in the first decade of the 21st century, there are as many ways to handle very preterm neonates as there are centers in which they are born. This brings to light the concept of medical stance, which is the general care approach prior to the treatment itself. This medical stance creates the overall framework for the staff's decision-making regarding neonate care. The different parameters structuring medical stance are discussed. Moreover, this study raises the problematic issue of the aftermath of benchmarking studies when the conclusion is an increase of morbidity in cases where procedure leads to more interventions.

Nasal CPAP in the delivery room for newborns with extremely low birth weight in a hospital in a developing country

The objective of this study was to determine the feasibility of the use of continuous positive airway pressure installed prophylactically in the delivery room (DR-CPAP), for infants with a birth weight between 500 and 1000 g in settings with limited resources. During 23 months, infants with a birth weight between 500 and 1000 g consecutively received DR-CPAP. A total of 33 infants with low birth weight were enrolled, 16 (48.5%) were females. Only 14 (42.4%) received antenatal corticosteroids and only 2 of those 14 (14.3%) infants weighing 500-750 g were not intubated in the delivery room, and apnea was given as the reason for intubation of these patients. Of the 19 infants in the 751-1000 g weight range, 9 (47.4%) were intubated in the delivery room, 6 due to apnea and 3 due to respiratory discomfort. For DR-CPAP to be successful, it is probably necessary for preterm babies to be more prepared at birth to withstand the respiratory effort without the need for intubation. Antenatal corticosteroids and better prenatal monitoring are fundamental for success of DR-CPAP.

Early regular versus late selective poractant treatment in preterm infants born between 25 and 30 gestational weeks: a prospective randomized multicenter study

OBJECTIVE

Surfactant treatment in the early hours of life significantly decreases the rates of death and air leak, and increases survival without bronchopulmonary dysplasia (BPD) in preterm infants. We aimed to compare the impact of early surfactant (ES) administration to late selective (LS) treatment on neonatal outcomes in preterm infants.

METHODS

All preterm infants between 25 and 30 wks gestational age and who were not entubated in the delivery room and did not have any major congenital malformation or perinatal asphyxia were randomized to ES treatment (200 mg/kg Curosurf® administration in 1 hour after birth) or LS treatment (200 mg/kg Curosurf®administration in the first 6 h of life if needed). The patients were treated by nasal continuous positive airway pressure (nCPAP) treatment regardless of the surfactant requirement. Outcomes were the necessity of mechanical ventilation, nCPAP duration, the oxygen requirement duration, the rates of BPD, retinopathy of prematurity (ROP) and mortality, and the assessment of the following situations; (pneumothorax, patent ductus arteriosus (PDA), necrotizing enterocolitis (NEC), and intraventricular hemorrhage (IVH) ≥ grade III).

RESULTS

Among 159 infants enrolled in the study, 79 were randomized to ES and 80 to LS treatment groups. Thirty-five patients (44%) in the LS treatment group needed surfactant administration. Necessity of second dose surfactant administration was 8.9% in the ES treatment group. Although necessity of mechanical ventilation, nCPAP duration, oxygen need duration, rates of PDA, NEC, BPD, ROP stage >3 and mortality did not show a significant difference between groups, the ES treatment group had lower rates of pneumothorax and IVH ≥ grade III when compared to the LS treatment group.

CONCLUSIONS

ES treatment decreases IVH (≥ grade III) and pneumothorax rates but does not have any effect on BPD when compared to LS.

Effect of HFNC flow rate, cannula size, and nares diameter on generated airway pressures: an in vitro study

Increased use of non-invasive forms of respiratory support such as CPAP and HFNC in premature infants has generated a need for further investigation of the pulmonary effects of such therapies. In a series of in vitro tests, we measured delivered proximal airway pressures from a HFNC system while varying both the cannula flow and the ratio of nasal prong to simulated nares diameters. Neonatal and infant sized nasal prongs (3.0 and 3.7 mm O.D.) were inserted into seven sizes of simulated nares (range: 3-7 mm I.D. from anatomical measurements in 1-3 kg infants) for nasal prong-to-nares ratios ranging from 0.43 to 1.06. The nares were connected to an active test lung set at: TV 10 ml, 60 breaths/min, Ti 0.35 sec, compliance 1.6 ml/cm H₂O and airway resistance 70 cm H₂O/(L/sec), simulating a 1-3 kg infant with moderately affected lungs. A Fisher & Paykel Healthcare HFNC system with integrated pressure relief valve was set to flow rates of 1-6 L/min while cannula and airway pressures and cannula and mouth leak flows were measured during simulated mouth open, partially closed and fully closed conditions. Airway pressure progressively increased with both increasing HFNC flow rate and nasal prong-to-nares ratio. At 6 L/min HFNC flow with mouth open, airway pressures remained <1.7 cm H₂O for all ratios; and <10 cm H₂O with mouth closed for ratios <0.9. For ratios >0.9 and 50% mouth leak, airway pressures rapidly increased to 18 cm H₂O at 2 L/min HFNC flow followed by a pressure relief valve limited increase to 24 cm H₂O at 6 L/min. Safe and effective use of HFNC requires careful selection of an appropriate nasal prong-to-nares ratio even with an integrated pressure relief valve.

Current trends in paediatric and neonatal ventilatory care -- a nationwide survey

AIM

To assess daily practices in paediatric and neonatal ventilatory care in Finland.

METHODS

All neonatal and paediatric intensive care units in Finland were sent a questionnaire on ventilatory strategies and were offered a 3-month prospective survey.

RESULTS

A total of 96% of units returned the questionnaire, and clinicians agreed on most of the principles of lung-protective ventilation. Seventeen hospitals (94%) joined the prospective survey. On average, 2.3 new ventilation episodes were started daily, and totally 211 episodes were monitored. Pulmonary problems (64%) were the main cause of treatment in neonates and postoperative care (68%) in older children. Synchronized intermittent mandatory ventilation with pressure support was the primary mode in 42% of episodes. Hypocapnia was observed repeatedly in all units. In adult intensive care units, children often received high oxygen fraction, leading to hyperoxia, and they were frequently sedated with propofol, which is not licensed for that purpose. A large proportion of children had only light sedation or no sedation at all. Despite the different strategies and practices, most episodes resulted in a favourable outcome.

CONCLUSION

Most of the principles of lung-protective ventilation have been well accepted by clinicians. More attention should be paid to achieving normocapnia and normoxia and to the correct use of sedatives, especially in units that only occasionally provide paediatric ventilation.

Outcome of extremely low gestational age newborns after introduction of a revised protocol to assist preterm infants in their transition to extrauterine life

AIM

To evaluate the outcome of a cohort of extremely low gestational age newborn infants (ELGAN) below 26-week gestation who were treated following a revised, gentle delivery room protocol to assist them in the transition and adaptation to extrauterine life.

METHODS

A cohort of infants with a gestational age (GA) below 26 weeks (study group; n = 164) was treated according to a revised delivery room protocol. The protocol included an optimized prenatal management, strict use of continuous positive airway pressure (CPAP), avoiding mechanical ventilation and early administration of surfactant without intubation. The parameters management of respiratory distress syndrome, survival, neonatal morbidity and neurodevelopmental outcome were compared with a historical control group (n = 44).

RESULTS

Seventy-four per cent of the study group infants were initially treated with CPAP and surfactant administration without intubation. In comparison with the control group, significantly less children were intubated in the delivery room (24% vs. 41%) and needed mechanical ventilation (51% vs. 72%; both p < 0.05). Furthermore, compared with the historical control overall mortality (20% vs. 39%), rate of bronchopulmonary dysplasia (18% vs. 37%) and IVH > II° (10% vs. 33%) in survivors were significantly lower during the observational period (all p < 0.05). Neurodevelopmental outcome was normal in 70% of examined study group infants.

CONCLUSIONS

A revised delivery room management protocol was applied safely to infants with a GA below 26 completed weeks with improved rates of survival and morbidity.

Nasal intermittent positive pressure ventilation after surfactant treatment for respiratory distress syndrome in preterm infants <30 weeks' gestation: a randomized, controlled trial

OBJECTIVE

To compare the effect of early extubation to nasal intermittent positive pressure ventilation (NIPPV) versus nasal continuous positive airway pressure (NCPAP) on the need for mechanical ventilation via endotracheal tube (MVET) at 7 days of age in preterm infants <30 weeks' gestation requiring intubation and surfactant for respiratory distress syndrome (RDS) within 60  min of delivery.

STUDY DESIGN

Multicenter, randomized, controlled trial. A total of 57 infants were randomized within 120  min of birth to NCPAP (BW 1099 g and GA 27.8 weeks) and 53 infants to NIPPV (BW 1052  g, and GA 27.8 weeks). Infants were stabilized on NCPAP at birth and were given poractant alfa combined with MVET within 60  min of age. When stabilized on MVET, they were extubated within the next hours or days to NCPAP or NIPPV.

RESULT

A total of 42% [corrected] of infants needed MVET at 7 days of age in the NCPAP group compared with 17% in the NIPPV group (OR: 3.6; 95% CI: 1.5, 8.7). Days on MVET were 12 ± 11 days in NCPAP group compared with 7.5 ± 12 days in the NIPPV group (median 1 vs 7 days; P=0.006). Clinical bronchopulmonary dysplasia (BPD) was 39% in the NCPAP group compared to 21% in the NIPPV group (OR: 2.4; 95% CI: 1.02, 5.6). Physiological BPD was 46% in the NCPAP group compared with 11% in the NIPPV group (OR: 6.6, 95% CI: 2.4, 17.8; P=0.001). There were no differences in any other outcomes between the two groups.

CONCLUSION

NIPPV compared with NCPAP reduced the need for MVET in the first week, duration of MVET, and clinical as well as physiological BPD in preterm infants receiving early surfactant for RDS.

RDS--CPAP or surfactant or both

There is mounting evidence that early continuous positive airway pressure (CPAP) from birth is feasible and safe even in very preterm infants. However, many infants will develop respiratory distress syndrome (RDS) and require surfactant treatment. Combining a non-invasive ventilation approach with a strategy for surfactant administration is important, but questions remain about the optimal timing, mode of delivery and the value of predictive tests for surfactant deficiency.

CONCLUSION

Early CPAP in very preterm infants is as safe as routine intubation in the delivery room. However, a strategy for surfactant administration should be part of a non-invasive ventilation approach for those infants at risk of developing significant RDS.

Morbidity and mortality of neonatal respiratory failure in China: surfactant treatment in very immature infants

OBJECTIVES

We retrospectively investigated incidence, morbidity, and mortality of neonatal respiratory failure (NRF) in China, with special emphasis on surfactant treated very immature infants.

METHODS

NRF was defined as respiratory hypoxemia requiring mechanical ventilation and/or nasal continuous positive airway pressure for at least 24 hours.

RESULTS

There were 6864 cases of NRF, composing 19.7% of total admissions to 55 NICUs in 2008. Of these cases, 62.8% were preterm, and 16.4% of very low birth weight (VLBW, <1500 g). The primary diseases were respiratory distress syndrome (RDS, 43.9%), pneumonia/sepsis (21.7%), transient respiratory insufficiency (14.7%), transient tachypnea (8.1%), and meconium aspiration syndrome (7.0%). Surfactant was given to 26.8% of infants with NRF and 54.8% infants with RDS. The survival rate of surfactant-treated RDS was 79.9% compared to 71.8% in those not receiving surfactant (P < .001). This was also true in those of VLBW, 59.8% vs 52.2% (P = .035), respectively. The overall survival rate in NRF cases was 75.3%, but it was 58.1% among VLBW infants; for those infants of 25, 26, and 27 to 28 weeks' gestational age, the survival rates were ∼6%, 30%, and 50%, respectively; and the survival rates for infants with meconium aspiration syndrome and pneumonia/sepsis were 70.3% and 71.4%, respectively. The care burden was associated with high treatment withdrawal and death rate.

CONCLUSIONS

The outcomes of NRF, especially in extremely premature infants, reflect both progress and persistent limitations in providing respiratory support in the emerging NICUs of China, but overall survival for sick newborns had improved steadily.

A comprehensive approach to the prevention of bronchopulmonary dysplasia

The current bronchopulmonary dysplasia (BPD) is seen in infants born extremely premature, with less severe respiratory distress syndrome (RDS) and who received prenatal steroids-"new BPD". The pathophysiology of BPD is based on an impairment of lung maturation with prenatal and postnatal multi-hit insults and genetic susceptibility. This multifactorial pathophysiology of BPD suggests that no single "magic bullet" will prevent it. Thus, to avoid BPD we need to implement a complex and comprehensive strategy. This strategy is based on ventilatory and non-ventilatory measures. The ventilatory route allows an individualized endotracheal intubation approach. Early lung recruitment with nasal respiratory support (nasal continuous positive airway pressure [NCPAP] or nasal intermittent positive pressure ventilation [NIPPV] / synchronized NIPPV [SNIPPV]) and the INSURE (intubation, surfactant and early extubation) approach are discussed. Initial treatment with NCPAP did not reduce the rate of BPD compared to endotracheal ventilation and surfactant administration. While NIPPV/SNIPPV may have short-term advantages over NCPAP, the effect on BPD needs to be further studied. During hospitalization the respiratory goals should aim for adequate oxygenation, permissive hypercapnia, and gentle ventilation. However, these goals were found to have short-term benefits but did not reduce significantly the rate of BPD. Selective use of a short course of low dose corticosteroids can be considered after the first or second week of life in infants who are unable to be weaned from the ventilator and are at high risk for BPD. Non-ventilatory measures include early nutritional support with fluid restriction, caffeine and consideration of vitamin A. Hemodynamic significant patent ductus arteriosus (PDA) may be associated with BPD, but medical or surgical treatment of PDA were not shown to decrease BPD. Each component and the strategy as a whole needs to be further studied in large randomized prospective studies or by meta-analyses, especially in the target population of extremely premature infants who are the most prone to BPD.

Respiratory symptoms in preterm infants: burden of disease in the first year of life

Objective

While respiratory symptoms in the first year of life are relatively well described for term infants, data for preterm infants are scarce. We aimed to describe the burden of respiratory disease in a group of preterm infants with and without bronchopulmonary dysplasia (BPD) and to assess the association of respiratory symptoms with perinatal, genetic and environmental risk factors.

Methods

Single centre birth cohort study: prospective recording of perinatal risk factors and retrospective assessment of respiratory symptoms during the first year of life by standardised questionnaires. Main outcome measures: Cough and wheeze (common symptoms), re-hospitalisation and need for inhalation therapy (severe outcomes). Patients: 126 preterms (median gestational age 28.7 weeks; 78 with, 48 without BPD) hospitalised at the University Children's Hospital of Bern, Switzerland 1999-2006.

Results

Cough occurred in 80%, wheeze in 44%, rehospitalisation in 25% and long term inhalation therapy in wheezers in 13% of the preterm infants. Using logistic regression, the main risk factor for common symptoms was frequent contact with other children. Severe outcomes were associated with maximal peak inspiratory pressure, arterial cord blood pH, APGAR and CRIB-Score.

Conclusions

Cough in preterm infants is as common as in term infants, whereas wheeze, inhalation therapy and re-hospitalisations occur more often. Severe outcomes are associated with perinatal risk factors. Preterm infants who did not qualify for BPD according to latest guidelines also showed a significant burden of respiratory disease in the first year of life.

Neonatal morbidity in moderately preterm infants: a Swedish national population-based study

OBJECTIVE

To determine the gestational age (GA)-specific risks for neonatal morbidity and use of interventions in infants born at 30 to 34 completed gestational weeks.

STUDY DESIGN

A population-based Swedish study including 6674 infants born during 2004-2008. Risks for neonatal morbidity and use of interventions were investigated with respect to GA and birth weight standard deviation scores.

RESULTS

Acute lung disorder was diagnosed in 28%, hypoglycemia in 16%, bacterial infection in 15% and hyperbilirubinemia in 59% of the infants. Thirty-eight percent had received antenatal steroid therapy, 43% nasal continuous positive airway pressure, 5.5% required mechanical ventilation, 5.2% were treated with surfactant, and 30% with antibiotic therapy. Neonatal morbidity rates increased with decreasing GA, with odds ratios for different outcomes ranging from 2.1 to 23 at 30 weeks compared with 34 weeks of GA. Low birth weight standard deviation scores was more common at lower GA and was associated with increased morbidity rates.

CONCLUSIONS

Despite general advances in perinatal care, moderately preterm infants still have substantially increased risks for neonatal morbidity. Whereas the neonatal morbidity rate was similar to results of previous reports, management of respiratory problems differed markedly from other studies.

Early CPAP versus surfactant in extremely preterm infants

BACKGROUND

There are limited data to inform the choice between early treatment with continuous positive airway pressure (CPAP) and early surfactant treatment as the initial support for extremely-low-birth-weight infants.

METHODS

We performed a randomized, multicenter trial, with a 2-by-2 factorial design, involving infants who were born between 24 weeks 0 days and 27 weeks 6 days of gestation. Infants were randomly assigned to intubation and surfactant treatment (within 1 hour after birth) or to CPAP treatment initiated in the delivery room, with subsequent use of a protocol-driven limited ventilation strategy. Infants were also randomly assigned to one of two target ranges of oxygen saturation. The primary outcome was death or bronchopulmonary dysplasia as defined by the requirement for supplemental oxygen at 36 weeks (with an attempt at withdrawal of supplemental oxygen in neonates who were receiving less than 30% oxygen).

RESULTS

A total of 1316 infants were enrolled in the study. The rates of the primary outcome did not differ significantly between the CPAP group and the surfactant group (47.8% and 51.0%, respectively; relative risk with CPAP, 0.95; 95% confidence interval [CI], 0.85 to 1.05) after adjustment for gestational age, center, and familial clustering. The results were similar when bronchopulmonary dysplasia was defined according to the need for any supplemental oxygen at 36 weeks (rates of primary outcome, 48.7% and 54.1%, respectively; relative risk with CPAP, 0.91; 95% CI, 0.83 to 1.01). Infants who received CPAP treatment, as compared with infants who received surfactant treatment, less frequently required intubation or postnatal corticosteroids for bronchopulmonary dysplasia (P<0.001), required fewer days of mechanical ventilation (P=0.03), and were more likely to be alive and free from the need for mechanical ventilation by day 7 (P=0.01). The rates of other adverse neonatal outcomes did not differ significantly between the two groups.

CONCLUSIONS

The results of this study support consideration of CPAP as an alternative to intubation and surfactant in preterm infants. (ClinicalTrials.gov number, NCT00233324.)

Global report on preterm birth and stillbirth (3 of 7): evidence for effectiveness of interventions

INTRODUCTION

Interventions directed toward mothers before and during pregnancy and childbirth may help reduce preterm births and stillbirths. Survival of preterm newborns may also be improved with interventions given during these times or soon after birth. This comprehensive review assesses existing interventions for low- and middle-income countries (LMICs).

METHODS

Approximately 2,000 intervention studies were systematically evaluated through December 31, 2008. They addressed preterm birth or low birth weight; stillbirth or perinatal mortality; and management of preterm newborns. Out of 82 identified interventions, 49 were relevant to LMICs and had reasonable amounts of evidence, and therefore selected for in-depth reviews. Each was classified and assessed by the quality of available evidence and its potential to treat or prevent preterm birth and stillbirth. Impacts on other maternal, fetal, newborn or child health outcomes were also considered. Assessments were based on an adaptation of the Grades of Recommendation Assessment, Development and Evaluation criteria.

RESULTS

Most interventions require additional research to improve the quality of evidence. Others had little evidence of benefit and should be discontinued. The following are supported by moderate- to high-quality evidence and strongly recommended for LMICs: Two interventions prevent preterm births--smoking cessation and progesterone. Eight interventions prevent stillbirths--balanced protein energy supplementation, screening and treatment of syphilis, intermittant presumptive treatment for malaria during pregnancy, insecticide-treated mosquito nets, birth preparedness, emergency obstetric care, cesarean section for breech presentation, and elective induction for post-term delivery. Eleven interventions improve survival of preterm newborns--prophylactic steroids in preterm labor, antibiotics for PROM, vitamin K supplementation at delivery, case management of neonatal sepsis and pneumonia, delayed cord clamping, room air (vs. 100% oxygen) for resuscitation, hospital-based kangaroo mother care, early breastfeeding, thermal care, and surfactant therapy and application of continued distending pressure to the lungs for respiratory distress syndrome

CONCLUSION

The research paradigm for discovery science and intervention development must be balanced to address prevention as well as improve morbidity and mortality in all settings. This review also reveals significant gaps in current knowledge of interventions spanning the continuum of maternal and fetal outcomes, and the critical need to generate further high-quality evidence for promising interventions.

The Stockholm Neonatal Family Centered Care Study: effects on length of stay and infant morbidity

OBJECTIVE

Parental involvement in the care of preterm infants in NICUs is becoming increasingly common, but little is known about its effect on infants' length of hospital stay and infant morbidity. Our goal was to evaluate the effect of a new model of family care (FC) in a level 2 NICU, where parents could stay 24 hours/day from admission to discharge.

METHODS

A randomized, controlled trial was conducted in 2 NICUs (both level 2), including a standard care (SC) ward and an FC ward, where parents could stay from infant admission to discharge. In total, 366 infants born before 37$$\raisebox{1ex}{$0$}\!\left/ \!\raisebox{-1ex}{$7$}\right.$$ weeks of gestation were randomly assigned to FC or SC on admission. The primary outcome was total length of hospital stay, and the secondary outcome was short-term infant morbidity. The analyses were adjusted for maternal ethnic background, gestational age, and hospital site.

RESULTS

Total length of hospital stay was reduced by 5.3 days: from a mean of 32.8 days (95% confidence interval [CI]: 29.6-35.9) in SC to 27.4 days (95% CI: 23.2-31.7) in FC (P = .05). This difference was mainly related to the period of intensive care. No statistical differences were observed in infant morbidity, except for a reduced risk of moderate-to-severe bronchopulmonary dysplasia: 1.6% in the FC group compared with 6.0% in the SC group (adjusted odds ratio: 0.18 [95% CI: 0.04-0.8]).

CONCLUSIONS

Providing facilities for parents to stay in the neonatal unit from admission to discharge may reduce the total length of stay for infants born prematurely. The reduced risk of moderate-to-severe bronchopulmonary dysplasia needs additional investigation.

Bubble continuous positive airway pressure, a potentially better practice, reduces the use of mechanical ventilation among very low birth weight infants with respiratory distress syndrome

OBJECTIVE

The purpose of this work was to assess a quality improvement initiative to implement a potentially better practice, bubble continuous positive airway pressure, to reduce bronchopulmonary dysplasia and improve other pulmonary outcomes among very low birth weight infants with respiratory distress syndrome.

METHODS

An initiative to implement the use of bubble continuous positive airway pressure is described that was based on the adoption of habits for change, collaborative learning, evidence-based practice, and process development. To assess the efficacy of this intervention, very low birth weight infants with respiratory distress syndrome born after implementation of bubble continuous positive airway pressure use (period 2: March 1, 2005, to October 4, 2007; N = 126) were compared with historical controls born during a previous period of ventilator use (period 1: January 1, 2003, to February 28, 2005; N = 88). Infants at both time periods were similar with respect to characteristics and aspects of perinatal care. Pulmonary outcomes compared for the 2 time periods included receipt of mechanical ventilation, duration of mechanical ventilation, pneumothoraces, and incidence of bronchopulmonary dysplasia. Nonpulmonary outcomes were also compared.

RESULTS

The use of mechanical ventilation declined during period 2. The mean duration (+ SD) of conventional ventilation during period 2 was shorter than during period 1 (3.08 + 6.17 vs 5.25 + 8.16 days), and fewer infants during period 2 required conventional ventilation for >6 days compared with those in period 1 (13.6% vs 26.3%). In regression models, the effect of period 2 persisted after controlling for other predictors of duration of conventional ventilation. There were no significant differences in other pulmonary or nonpulmonary outcomes, with the exception of mild retinopathy of prematurity (stage I or II), which was more common during period 2. The enhanced odds of retinopathy of prematurity persisted after controlling for other known predictors of this condition.

CONCLUSION

Among very low birth weight infants with respiratory distress syndrome, the use of bubble continuous positive airway pressure is a potentially better practice that may reduce the use of mechanical ventilation. Although an increase in retinopathy of prematurity was observed in our population, carefully designed randomized, controlled trials will be required to more accurately address the potential risks and benefits of this therapy.

Outcome of very low birthweight infants after introducing a new standard regime with the early use of nasal CPAP

In this paper, a retrospective study was performed to find out whether the introduction of early nasal continuous positive airway pressure (nCPAP) as a new standard regime of very low birthweight infants will lead to a decreasing tracheal intubation and ventilation rate, as well as to a lower incidence of bronchopulmonary dysplasia in a tertiary-level perinatal centre. Ninety-three infants (study group) with early nCPAP as the first respiratory support were compared to 63 infants (historical control group) born before the use of early nCPAP. No statistically significant differences were found in the baseline characteristics. The main results of the study include reduced intubation mainly in infants with a birthweight <1,000 g (study group): 58% vs. 81% (p < 0.05). The mean duration of ventilation was 248 h (control group) vs. 128 h (study group) (p < 0.001) and 437 h vs. 198 h in infants <1,000 g (p < 0.001). There was significantly reduced incidence of bronchopulmonary dysplasia from 55% to 18% for all surviving infants (p < 0.001), and for infants <1,000 g, it was 90% vs. 30% (p < 0.001). No significant differences for other outcome criteria were noted, but a significant reduction in the use of central i.v. lines, fluids, drugs, volume expansion, sedation, catecholamines, surfactant, steroids and buffer, as well as antibiotics, was observed (p < 0.05). Therefore, we can conclude that early nCPAP is an easy-to-use and safe procedure for very low birthweight infants to treat respiratory distress.

Nasal ventilation alters mesenchymal cell turnover and improves alveolarization in preterm lambs

RATIONALE

Bronchopulmonary dysplasia (BPD) is a frequent cause of morbidity in preterm infants that is characterized by prolonged need for ventilatory support in an intensive care environment. BPD is characterized histopathologically by persistently thick, cellular distal airspace walls. In normally developing lungs, by comparison, remodeling of the immature parenchymal architecture is characterized by thinning of the future alveolar walls, a process predicated on cell loss through apoptosis.

OBJECTIVES

We hypothesized that minimizing lung injury, using high-frequency nasal ventilation to provide positive distending pressure with minimal assisted tidal volume displacement, would increase apoptosis and decrease proliferation among mesenchymal cells in the distal airspace walls compared with a conventional mode of support (intermittent mandatory ventilation).

METHODS

Accordingly, we compared two groups of preterm lambs: one group managed by high-frequency nasal ventilation and a second group managed by intermittent mandatory ventilation. Each group was maintained for 3 days.

MEASUREMENTS AND MAIN RESULTS

Oxygenation and ventilation targets were sustained with lower airway pressures and less supplemental oxygen in the high-frequency nasal ventilation group, in which alveolarization progressed. Thinning of the distal airspace walls was accompanied by more apoptosis, and less proliferation, among mesenchymal cells of the high-frequency nasal ventilation group, based on morphometric, protein abundance, and mRNA expression indices of apoptosis and proliferation.

CONCLUSIONS

Our study shows that high-frequency nasal ventilation preserves the balance between mesenchymal cell apoptosis and proliferation in the distal airspace walls, such that alveolarization progresses.

Achievement of targeted saturation values in extremely low gestational age neonates resuscitated with low or high oxygen concentrations: a prospective, randomized trial

OBJECTIVE

Extremely low gestational age neonates have very low oxygen saturation in utero and an immature antioxidant defense system. Abrupt increases in oxygen saturation after birth may cause oxidative stress. We compared achievement of a targeted oxygen saturation of 85% at 10 minutes of life when resuscitation was initiated with low or high fractions of inspired oxygen and levels were adjusted according to preductal pulse oxygen saturation values.

METHODS

A prospective, randomized, clinical trial was performed in 2 level III neonatal referral units. Patients of < or = 28 weeks of gestation who required active resuscitation were randomly assigned to the low-oxygen group (fraction of inspired oxygen: 30%) or the high-oxygen group (fraction of inspired oxygen: 90%). Every 60 to 90 seconds, the fraction of inspired oxygen was increased in 10% steps if bradycardia occurred (< 100 beats per minute) or was decreased in similar steps if pulse oxygen saturation reached values of > 85%. Preductal pulse oxygen saturation was continuously monitored.

RESULTS

The fraction of inspired oxygen in the low-oxygen group was increased stepwise to 45% and that in the high-oxygen group was reduced to 45% to reach a stable pulse oxygen saturation of approximately 85% at 5 to 7 minutes in both groups. No differences in oxygen saturation in minute-to-minute registers were found independent of the initial fraction of inspired oxygen used 4 minutes after cord clamping. No differences in mortality rates in the early neonatal period were detected.

CONCLUSIONS

Resuscitation can be safely initiated for extremely low gestational age neonates with a low fraction of inspired oxygen (approximately 30%), which then should be adjusted to the infant's needs, reducing the oxygen load to the neonate.

Continuous positive airway pressure: scientific and clinical rationale

PURPOSE OF REVIEW

To present recent data on the role of noninvasive ventilation in the respiratory management of newborn infants.

RECENT FINDINGS

Noninvasive ventilation is growing in popularity but is applied using widely varying devices and settings. Although short-term physiological advantages were reported for bubble and variable-flow continuous positive airways pressure, neither has convincingly shown superior clinically important outcomes. Continuous positive airways pressure may be used as the initial mode of support for very preterm infants but increased rates of pneumothorax in infants not receiving surfactant are a concern. Methods of administering surfactant without endotracheal intubation deserve further study. Nasal intermittent positive-pressure ventilation shows promise as a primary treatment for respiratory distress syndrome. Optimal pressure settings for continuous positive airways pressure and nasal intermittent positive-pressure ventilation remain uncertain.

SUMMARY

Noninvasive ventilation has partially fulfilled its promise as a gentler alternative to ventilation via an endotracheal tube. Appropriately designed randomized clinical trials are required to determine the best nasal interfaces and pressure generators.

What is new in ventilation strategies for the neonate?

A large number of ventilation strategies are now available for the neonate. This review has focused on new information, that is, studies published since 2000 and the implication of their results for current clinical practice. Meta-analysis of randomised trials has demonstrated that assist control and synchronous intermittent mandatory ventilation (SIMV) shortens the duration of ventilation only if started in the recovery rather than the early stage of respiratory disease. A recent randomised trial demonstrated pressure-regulated volume control ventilation may also have no advantages if started early. Weaning by SIMV with pressure support is better (reducing oxygen dependency) than SIMV alone. Meta-analysis of volume-targeted ventilation demonstrated significant reductions in the duration of ventilation and pneumothorax, but the trials were small and of different designs. Volume guarantee may provide more consistent blood gas control. The level of volume targeting appears to be crucial to the success of this technique. Meta-analysis of randomised trials of prophylactic high-frequency oscillation trials has shown a modest reduction in bronchopulmonary dysplasia. Randomised trials have failed to confirm the advantages of nasal continuous positive airway pressure (NCPAP) seen in various non-randomised studies; however, the randomised trials reported to date have been small. Inhaled nitric oxide (NO) does not improve the outcome of prematurely born infants with severe respiratory failure, but early low-dose prolonged iNO appears to have benefits that merit further testing. More randomised trials with long-term outcomes are required to identify the optimal ventilation strategy(ies) for the neonate.

Brain abnormalities in extremely low gestational age infants: a Swedish population based MRI study

AIMS

Brain abnormalities are common in preterm infants and can be reliably detected by magnetic resonance (MR) imaging at term equivalent age. The aim of the present study was to acquire population based data on brain abnormalities in extremely low gestational age (ELGA) infants from the Stockholm region and to correlate the MR findings to perinatal data, in order to identify risk factors.

METHODS

All infants with gestational age <27 weeks, born in the Stockholm region between January 2004 and August 2005, were scanned on a 1.5 T MR system at term equivalent age. Images were analysed using a previously established scoring system for grey and white matter abnormalities.

RESULTS

No or only mild white matter abnormalities were observed in 82% and moderate to severe white matter abnormalities in 18% of infants. The Clinical Risk Index for Babies (CRIB II) score, use of inotropes, the presence of high-grade intraventricular haemorrhages and posthaemorrhagic ventricular dilatation were associated with white matter abnormalities.

CONCLUSION

The incidence of moderate to severe white matter abnormalities in a population-based cohort of ELGA infants from the Stockholm region was 18%. To examine the clinical relevance of these promising results, neurodevelopmental follow up at 30 month corrected age, is ongoing.