Duration of and trends in respiratory support among extremely preterm infants

Noninvasive Respiratory Support or Intubation during Stabilization after Birth and Neonatal and Neurodevelopmental Outcomes in Infants Born Preterm at 23-25 Weeks of Gestation

OBJECTIVE

To examine the association between noninvasive respiratory support (NRS) or tracheal intubation (TI) during stabilization in infants born at 23-25 weeks of gestation and severe brain injury (sBI) or death, and significant neurodevelopmental impairment (sNDI).

STUDY DESIGN

A retrospective cohort study of infants born at 23°/7-256/7 weeks of gestation in Canada. We compared infants successfully managed with NRS or TI during 30 minutes after birth. The primary outcomes were sBI or death before discharge, and sNDI among survivors with follow-up data at 18-24 months corrected age. The associations between exposures and outcomes were assessed using logistic regression models, and propensity score-matched analyses.

RESULTS

The mean (SD) of gestational age and birth weight were 24.6 (0.6), 24.3 (0.7) weeks [P < .01], and 757 (173), 705 (130) grams [P < .01] in the NRS, and tracheal intubation (TI) groups, respectively, and 77% of infants in the NRS group were intubated by 7 days of age. sBI or death occurred in 25% (283/1118), and 36% (722/2012) of infants in the NRS and TI groups, respectively (aOR and 95% CI 0.74 [0.60, 0.91]). Among survivors with follow-up data, sNDI occurred in 17% (96/551), and 23% (218/937) of infants in the NRS and TI groups, respectively (aOR [95% CI] 0.77 [0.60, 0.99]). In the propensity score-matched analyses (NRS vs TI), results were consistent for sBI or death (OR [95% CI] 0.72 [0.60, 0.86]), but not for sNDI (OR [95% CI] 0.78 [0.58, 1.05]).

CONCLUSIONS

Infants born at 23-25 weeks who were successfully managed with NRS, compared with TI, in the first 30 minutes after birth had lower odds of sBI or death before discharge, but had no significant differences in neurodevelopmental outcomes among survivors.

Surfactant treatment at birth in a contemporary cohort of preterm infants with bronchopulmonary dysplasia

OBJECTIVE

Initial surfactant studies demonstrated improvements in survival and need for respiratory support. However, as the use of non-invasive respiratory support has increased the use of surfactant has decreased. We examined in a contemporary cohort of BPD patients if surfactant use was associated with BPD severity.

STUDY DESIGN

An observational study using data from the BPD Collaborative Registry.

RESULTS

971 infants with BPD met entry criteria, 864 (89%) had received surfactant in the first 72 h of life (SURF) and the remainder had not (no surfactant). There was an association between SURF and BPD grade, with a greater likelihood of grade 3 BPD in infants who received surfactant in the DR or who had 2 or more doses.

CONCLUSIONS

We speculate that the use of surfactant in the DR and use of multiple doses reflect the impact of perinatal factors beyond immaturity alone that increase the risk for grade 3 BPD.

Weaning from mechanical ventilation and assessment of extubation readiness

Tremendous advancements in neonatal respiratory care have contributed to the improved survival of extremely preterm infants (gestational age ≤ 28 weeks). While mechanical ventilation is often considered one of the most important breakthroughs in neonatology, it is also associated with numerous short and long-term complications. For those reasons, clinical research has focused on strategies to avoid or reduce exposure to mechanical ventilation. Nonetheless, in the extreme preterm population, 70-100% of infants born 22-28 weeks of gestation are exposed to mechanical ventilation, with nearly 50% being ventilated for ≥ 3 weeks. As contemporary practices have shifted towards selectively reserving mechanical ventilation for those patients, mechanical ventilation weaning and extubation remain a priority yet offer a heightened challenge for clinicians. In this review, we will summarize the evidence for different strategies to expedite weaning and assess extubation readiness in preterm infants, with a particular focus on extremely preterm infants.

Total liquid ventilation in an ovine model of extreme prematurity: a randomized study

BACKGROUND

This study aimed at comparing cardiorespiratory stability during total liquid ventilation (TLV)-prior to lung aeration-with conventional mechanical ventilation (CMV) in extremely preterm lambs during the first 6 h of life.

METHODS

23 lambs (11 females) were born by c-section at 118-120 days of gestational age (term = 147 days) to receive 6 h of TLV or CMV from birth. Lung samples were collected for RNA and histology analyses.

RESULTS

The lambs under TLV had higher and more stable arterial oxygen saturation (p = 0.001) and cerebral tissue oxygenation (p = 0.02) than the lambs in the CMV group in the first 10 min of transition to extrauterine life. Although histological assessment of the lungs was similar between the groups, a significant upregulation of IL-1a, IL-6 and IL-8 RNA in the lungs was observed after TLV.

CONCLUSIONS

Total liquid ventilation allowed for remarkably stable transition to extrauterine life in an extremely preterm lamb model. Refinement of our TLV prototype and ventilation algorithms is underway to address specific challenges in this population, such as minimizing tracheal deformation during the active expiration.

IMPACT

Total liquid ventilation allows for remarkably stable transition to extrauterine life in an extremely preterm lamb model. Total liquid ventilation is systematically achievable over the first 6 h of life in the extremely premature lamb model. This study provides additional incentive to pursue further investigation of total liquid ventilation as a transition tool for the most extreme preterm neonates.

Trends in bronchopulmonary dysplasia and respiratory support among extremely preterm infants in China over a decade

OBJECTIVE

Bronchopulmonary dysplasia (BPD) is one of the most serious complications affecting extremely preterm infants. We aimed to evaluate temporal trends in BPD and administration of respiratory support among extremely preterm infants in China over a decade.

METHODS

This was a retrospective study using data from a multicenter database, which included infants born less than 28 weeks' gestation discharged from 68 tertiary neonatal care centers in China between 2010 and 2019. Changes in rates and severity of BPD, as well as modalities and duration of respiratory support, were evaluated.

RESULTS

Among 4808 eligible infants with gestational age (GA) of 21+6/7  to 27+6/7 weeks and a mean (SD) birth weight of 980 (177) g, no significant change of median GA was found over time. Overall, 780 (16.2%) infants died before 36 weeks' postmenstrual age, 2415 (50.2%) were classified as having no BPD, 917 (19.1%) developed Grade 1 BPD, 578 (12.0%) developed Grade 2 BPD, and 118 (2.5%) developed Grade 3 BPD. The rate of BPD increased from 20.8% in 2010 to 40.7% in 2019 (aRR for trend, 1.081; 95% confidence interval, 1.062-1.099), especially for Grade 1 and Grade 2. Although survival to discharge improved over the decade, the overall survival without BPD did not change during the study period. The use of invasive mechanical ventilation (IMV) remained unchanged. However, the use of noninvasive ventilation (NIV) increased from 71.5% in 2010 to 89.8% in 2019. Moreover, the median duration of NIV increased over time, from 17.0 (4.8, 34.0) days in 2010 to 33.0 (21.0, 44.0) days in 2019, without significant change in the duration of IMV.

CONCLUSIONS

Although survival increased over the decade and respiratory support practices changed significantly between 2010 and 2019 in China, with increased use and duration of NIV, there was an increased rate of BPD and survival without BPD has not improved.

Can we balance early exogenous surfactant therapy and non-invasive respiratory support to optimise outcomes in extremely preterm infants? A nuanced review of the current literature

Therapeutic advances have significantly improved the survival of premature infants. However, a high burden of bronchopulmonary dysplasia (BPD) persists. Aiming at prevention of neonatal lung injury, continuous positive airway pressure (CPAP) and non-invasive ventilation (NIV) strategies have replaced mechanical ventilation for early respiratory support and treatment of respiratory distress syndrome. Multiple randomised controlled trials have demonstrated that broad application of CPAP/NIV decreases exposure to mechanical ventilation and reduces rates of BPD. Here, we explore why this treatment effect is not larger. We discuss that today's neonatal intensive care unit population evolving from the premature to the extremely premature infant demands better targeted therapy, and indicate how early and accurate identification of preterm infants likely to fail CPAP/NIV could increase the treatment effect and minimise the potential harm of delaying exogenous surfactant therapy in these infants. Finally, we argue that less invasive modes of surfactant administration may represent both a pragmatic and beneficial approach in combining CPAP/NIV and early surfactant. Beneficial treatment effects might be higher than reported in the literature when targeting this approach to preterm infants suffering from respiratory failure primarily due to surfactant deficiency. Considering ongoing limitations of current approaches and focusing both on prospects and potential harm of modified strategies, this commentary ultimately addresses the need and the challenge to prove that pushing early CPAP/NIV and strategies of early and less invasive surfactant application prevents lung injury in the long term.

Optimal timing of extubation in preterm infants

In neonatal intensive care, endotracheal intubation is usually performed as an urgent or semi-urgent procedure in infants with critical or unstable conditions related to progressive respiratory failure. Extubation is not. Patients undergoing extubation are typically stable, with improved respiratory function. The key elements to facilitating extubation are to recognize improvement in respiratory status, promote weaning of mechanical ventilation, and accurately identify readiness for removal of the endotracheal tube. Therefore, extubation should be a planned and well-organized procedure. In this review, we will appraise the evidence for existing predictors of extubation readiness and provide patient-specific, pathophysiology-derived strategies to optimize the timing and success of extubation in neonates, with a focus on extremely preterm infants.

Required biological time for lung maturation and duration of invasive ventilation: a Korean cohort study of very low birth weight infants

Background

We investigated the duration of invasive ventilation among very low birth weight (VLBW) infants to evaluate the current minimum time required for lung maturation to breathe without ventilator assistance after preterm birth.

Methods

A total of 14,658 VLBW infants born at ≤32⁺⁶ weeks between 2013 and 2020 were enrolled. Clinical data were collected from the Korean Neonatal Network, a national prospective cohort registry of VLBW infants from 70 neonatal intensive care units. Differences in the duration of invasive ventilation according to gestational age and birth weight were investigated. Recent trends and changes in assisted ventilation duration and associated perinatal factors between 2017-20 and 2013-16 were compared. Risk factors related to the duration of assisted ventilation were also identified.

Results

The overall duration of invasive ventilation was 16.3 days and the estimated minimum time required corresponded to 30⁺⁴ weeks of gestation. The median duration of invasive ventilation was 28.0, 13.0, 3.0, and 1.0 days at <26, 26-27, 28-29, and 30-32 weeks of gestation, respectively. In each gestational age group, the estimated minimum weaning points from the assisted ventilator were 29⁺⁵, 30⁺², 30⁺², and 31⁺⁵ weeks of gestation. The duration of non-invasive ventilation (17.9 vs. 22.5 days) and the incidence of bronchopulmonary dysplasia (28.1% vs. 31.9%) increased in 2017-20 (n = 7,221) than in 2013-16 (n = 7,437). In contrast, the duration of invasive ventilation and overall survival rate did not change during the periods 2017-20 and 2013-16. Surfactant treatment and air leaks were associated with increased duration of invasive ventilation (inverse hazard ratio 1.50, 95% CI, 1.04-2.15; inverse hazard ratio 1.62, 95% CI, 1.29-2.04). We expressed the incidence proportion of ventilator weaning according to the invasive ventilation duration using Kaplan-Meier survival curves. The slope of the curve slowly decreased as gestational age and birth weight were low and risk factors were present.

Conclusions

This population-based data on invasive ventilation duration among VLBW infants suggest the present limitation of postnatal lung maturation under specific perinatal conditions after preterm birth. Furthermore, this study provides detailed references for designing and/or assessing earlier ventilator weaning protocols and lung protection strategies by comparing populations or neonatal networks.

Cerebral Oximetry Monitoring in Extremely Preterm Infants

BACKGROUND

The use of cerebral oximetry monitoring in the care of extremely preterm infants is increasing. However, evidence that its use improves clinical outcomes is lacking.

METHODS

In this randomized, phase 3 trial conducted at 70 sites in 17 countries, we assigned extremely preterm infants (gestational age, <28 weeks), within 6 hours after birth, to receive treatment guided by cerebral oximetry monitoring for the first 72 hours after birth or to receive usual care. The primary outcome was a composite of death or severe brain injury on cerebral ultrasonography at 36 weeks' postmenstrual age. Serious adverse events that were assessed were death, severe brain injury, bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, and late-onset sepsis.

RESULTS

A total of 1601 infants underwent randomization and 1579 (98.6%) were evaluated for the primary outcome. At 36 weeks' postmenstrual age, death or severe brain injury had occurred in 272 of 772 infants (35.2%) in the cerebral oximetry group, as compared with 274 of 807 infants (34.0%) in the usual-care group (relative risk with cerebral oximetry, 1.03; 95% confidence interval, 0.90 to 1.18; P = 0.64). The incidence of serious adverse events did not differ between the two groups.

CONCLUSIONS

In extremely preterm infants, treatment guided by cerebral oximetry monitoring for the first 72 hours after birth was not associated with a lower incidence of death or severe brain injury at 36 weeks' postmenstrual age than usual care. (Funded by the Elsass Foundation and others; SafeBoosC-III ClinicalTrials.gov number, NCT03770741.).

Instrumental dead space: A glass ceiling for extremely low birth weight preterm infants? A dead space washout bench study

BACKGROUND

When ventilating extremely low birth weight infants, clinicians face the problem of instrumental dead space, which is often larger than tidal volume. Hence, aggressive ventilation is necessary to achieve CO₂ removal. Continuous tracheal gas insufflation can wash out CO₂ from dead space and might also have an impact on O₂ and water vapor transport. The objective of this bench study is to test the impact of instrumental dead space on the transport of CO₂ , O₂ , and water vapor and the ability of continuous tracheal gas insufflation to remedy this problem during small tidal volume ventilation.

METHODS

A test-lung located in an incubator at 37°C was ventilated with pressure levels needed to reach different tidal volumes from 1.5 to 5 mL. End-tidal CO₂ at the test-lung exit, O₂ concentration, and relative humidity in the test-lung were measured for each tidal volume with and without a 0.2 L/min continuous tracheal gas insufflation flow.

RESULTS

CO₂ clearance was improved by continuous tracheal gas insufflation allowing a 28%-44% of tidal volume reduction. With continuous tracheal gas insufflation, time to reach desired O₂ concentration was reduced from 20% to 80% and relative humidity was restored. These results are inversely related to tidal volume and are particularly critical below 3 mL.

CONCLUSION

For the smallest tidal volumes, reduction of instrumental dead space seems mandatory for CO₂ , O₂ , and water vapor transfer. Continuous tracheal gas insufflation improved CO₂ clearance, time to reach desired O₂ concentration and humidification of airways and, thus, may be an option to protect lung development.

Association of newer definitions of bronchopulmonary dysplasia with pulmonary hypertension and long-term outcomes

BACKGROUND

The definition of bronchopulmonary dysplasia (BPD) has been evolved recently from definition by the National Institute of Child Health and Human Development in 2001 (NICHD 2001) to the definition reported in 2018 (NICHD 2018) and that proposed by Jensen et al. in 2019 (NICHD 2019). The definition was developed based on the evolution of non-invasive respiratory support and to achieve better prediction of later outcomes. Our objective was to evaluate the association between different definitions of BPD and occurrence of pulmonary hypertension (PHN) and long term outcomes.

METHODS

This retrospective study enrolled preterm infants born at < 32 weeks of gestation between 2014 and 2018. The association between re-hospitalization owing to a respiratory illness until a corrected age (CA) of 24 months, neurodevelopmental impairment (NDI) at a CA of 18-24 months, and PHN at a postmenstrual age (PMA) of 36 weeks was evaluated, with the severity of BPD defined based on these three definitions.

RESULTS

Among 354 infants, the gestational age and birth weight were the lowest in severe BPD based on the NICHD 2019 definition. In total, 14.1% of the study population experienced NDI and 19.0% were re-hospitalized owing to a respiratory illness. At a PMA of 36 weeks, PHN was identified in 9.2% of infants with any BPD. Multiple logistic regression analysis showed that the adjusted odds ratio (OR) for re-hospitalization was the highest for Grade 3 BPD of the NICHD 2019 criteria (5.72, 95% confidence interval [CI]: 1.37-23.92), while the adjusted OR of Grade 3 BPD was 4.96 (95% CI: 1.73-14.23) in the NICHD 2018 definition. Moreover, no association of the severity of BPD was found in the NICHD 2001 definition. The adjusted ORs for NDI (12.09, 95% CI: 2.52-58.05) and PHN (40.37, 95% CI: 5.15-316.34) were also the highest for Grade 3 of the NICHD 2019 criteria.

CONCLUSION

Based on recently suggested criteria by the NICHD in 2019, BPD severity is associated with long-term outcomes and PHN at a PMA of 36 weeks in preterm infants.

Noninvasive Neurally Adjusted Ventilation in Postextubation Stabilization of Preterm Infants: A Randomized Controlled Study

OBJECTIVE

To compare the effects of noninvasive neurally adjusted ventilatory assist (NIV-NAVA) to nasal continuous positive airway pressure (NCPAP) in achieving successful extubation in preterm infants.

STUDY DESIGN

This prospective, single-center, randomized controlled trial enrolled preterm infants born at <30 weeks of gestation who received invasive ventilation. Participants were assigned at random to either NIV-NAVA or NCPAP after their first extubation from invasive ventilation. The primary outcome of the study was extubation failure within 72 hours of extubation. Electrical activity of the diaphragm (Edi) values were collected before extubation and at 1, 4, 12, and 24 hours after extubation.

RESULTS

A total of 78 infants were enrolled, including 35 infants in the NIV-NAVA group and 35 infants in the NCPAP group. Extubation failure within 72 hours of extubation was higher in the NCPAP group than in the NIV-NAVA group (28.6% vs 8.6%; P = .031). The duration of respiratory support and incidence of severe bronchopulmonary dysplasia were similar in the 2 groups. Peak and swing Edi values were comparable before and at 1 hour after extubation, but values at 4, 12, and 24 hours after extubation were lower in the NIV-NAVA group compared with the NCPAP group.

CONCLUSIONS

In the present trial, NIV-NAVA was more effective than NCPAP in preventing extubation failure in preterm infants.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02590757.

Variation and Temporal Trends in Delivery Room Management of Moderate and Late Preterm Infants

BACKGROUND

Although delivery room (DR) intervention decreases with increasing gestational age (GA), little is known about DR management of moderate and late preterm (MLP) infants.

METHODS

Using the Vermont Oxford Network database of all NICU admissions, we examined the receipt of DR interventions including supplemental oxygen, positive pressure ventilation, continuous positive airway pressure, endotracheal tube ventilation, chest compressions, epinephrine, and surfactant among MLP infants (30 to 36 weeks') without congenital anomalies born from 2011 to 2020. Pneumothorax was examined as a potential resuscitation-associated complication. Intervention frequency was assessed at the infant- and hospital-level, stratified by GA and over time.

RESULTS

Overall, 55.3% of 616 110 infants (median GA: 34 weeks) from 483 Vermont Oxford Network centers received any DR intervention. Any DR intervention frequency decreased from 89.7% at 30 weeks to 44.2% at 36 weeks. From 2011 to 2020, there was an increase in the provision of continuous positive airway pressure (17.9% to 47.8%, P ≤.001) and positive pressure ventilation (22.9% to 24.9%, P ≤.001) and a decrease in endotracheal tube ventilation (6.9% to 4.0% P ≤.001), surfactant administration (3.5% to 1.3%, P ≤.001), and pneumothorax (1.9% to 1.6%, P ≤.001). Hospital rates of any DR intervention varied (median 54%, interquartile range 47% to 62%), though the frequency was similar across hospitals with different NICU capabilities after adjustment.

CONCLUSIONS

The DR management of MLP infants varies at the individual- and hospital-level and is changing over time. These findings illustrate the differing interpretation of resuscitation guidelines and emphasize the need to study MLP infants to improve evidence-based DR care.

Does closed-loop automated oxygen control reduce the duration of mechanical ventilation? A randomised controlled trial in ventilated preterm infants

BACKGROUND

Many preterm infants require supplemental oxygen in the newborn period but experience frequent fluctuations of their oxygen saturation levels. Intermittent episodes of hypoxia or hyperoxia increase the risk of complications. Compliance with achievement of oxygen saturation targets is variable, and the need for frequent adjustments of the inspired oxygen concentration increases workload. Closed-loop automated oxygen control systems (CLAC) improve achievement of oxygen saturation targets and reduce both episodes of hypoxia and hyperoxia and the number of manual adjustments. This study investigates whether CLAC compared with manual oxygen control reduces the duration of mechanical ventilation in preterm infants born at less than 31 weeks of gestation.

METHODS

This randomised controlled trial performed at a single tertiary neonatal unit is recruiting 70 infants born at less than 31 weeks of gestational age and within 48 h of initiation of mechanical ventilation. Infants are randomised to CLAC or manual oxygen control from recruitment until successful extubation. The primary outcome is the duration of mechanical ventilation, and secondary outcomes are the percentage of time spent within target oxygen saturation ranges, the time spent in hypoxia or hyperoxia, the number of manual adjustments required, the number of days on oxygen, the incidence of bronchopulmonary dysplasia and the length and cost of neonatal unit stay. The study is performed following informed parental consent and was approved by the Yorkshire and the Humber-Sheffield Research Ethics Committee (protocol version 1.1, 13 July 2021).

DISCUSSION

This trial will investigate the effect of CLAC on the duration of mechanical ventilation, which is an important clinical outcome as prolonged mechanical ventilation is associated with important adverse outcomes, such as bronchopulmonary dysplasia.

TRIAL REGISTRATION

ClinicalTrials.Gov NCT05030337 . Registered on 17 August 2021.

Predictors of successful trial off continuous positive airway pressure and high flow nasal cannula in preterm infants <30 weeks' gestation: A retrospective study

OBJECTIVES

To identify the predictors of successful first trial off nasal continuous positive airway pressure (nCPAP).

METHODS

A retrospective cohort study of infants ≤29 weeks' gestation who required nCPAP for >24 h was conducted. Logistic regression was used to detect predictors for successful trial off nCPAP. Statistical analysis was performed using the SAS software.

RESULTS

A total of 727 infants were included in the analysis. Infants who were successful in their first trial off nCPAP (n = 313) were of higher gestational age (GA) and birth weight (BW), as well as a higher proportion of female infants, compared with those who were not successful (p < 0.01). When stratified by GA, a negative correlation was noted between GA and postmenstrual age at successful trial off nCPAP or high flow nasal cannula (HFNC) (r = 0.45, p < 0.01). Logistic regression analysis showed that GA (odds ratio [OR] 1.13, 95% confidence interval [CI] [1.03-1.24], p = 0.01) and percentage of time spent with an oxygen saturation over 89% in the 24 h preceding the trial off nCPAP (OR 1.08, 95% CI [1.05-1.11], p = 0.00) were independent predictors for successful trial off nCPAP.

CONCLUSION

Successful trial off nCPAP or HFNC in preterm infants is significantly associated with higher GA, BW, female gender, and the specific oxygen saturation histogram in the preceding 24-h period.

Changes in Use of Respiratory Support for Preterm Infants in the US, 2008-2018

IMPORTANCE

In preterm infants, mechanical ventilation (MV) is associated with adverse pulmonary and neurodevelopmental outcomes. Multiple randomized clinical trials over the past 2 decades have shown the effectiveness of early noninvasive ventilation (NIV) in decreasing the use of MV in preterm infants. The epidemiologic factors associated with respiratory support in US preterm infants and any temporal changes after these trials is unknown.

OBJECTIVE

To evaluate temporal changes in MV and noninvasive respiratory support in US preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

In a cohort design, 2 large national data sets (Pediatrix Clinical Data Warehouse for the clinical cohort and National Inpatient Sample for the national cohort) were used to collect data on preterm infants (<35 weeks' gestation) without congenital anomalies who received active intensive care and were discharged home or died in the birth hospital from January 1, 2008, to December 31, 2018. Data analysis was conducted from December 10, 2019, to December 16, 2020.

EXPOSURE

Discharge year.

MAIN OUTCOME AND MEASURES

In the clinical cohort, detailed respiratory support data were generated, including days of MV and NIV modalities, and temporal trends were evaluated using multivariable modified Poisson or negative binomial regression models with discharge year as a continuous variable. In the national cohort, observed and expected national MV use were calculated.

RESULTS

Among 259 311 infants (47.2% female) in 359 neonatal intensive care units in the clinical cohort, decreases were noted in the use (from 29.4% of infants in 2008 to 18.5% in 2018, relative risk for annual change, 0.96; 95% CI, 0.95-0.96) and duration (mean days, from 10.3 in 2008 to 9.7 in 2018; rate ratio for annual change, 0.98; 95% CI, 0.97-0.98) of MV. Noninvasive ventilation use increased from 57.9% of infants in 2008 to 67.4% in 2018 (adjusted relative risk for annual change, 1.02; 95% CI, 1.02-1.03), and mean NIV duration increased by 3.2 days (95% CI, 2.9-3.6 days). With increased use of continuous positive airway pressure and nasal intermittent positive-pressure ventilation as the main factors in the increase, the mean duration of respiratory support increased from 13.8 to 15.4 days (adjusted rate ratio for annual change, 1.03; 95% CI, 1.02-1.04) from 2008 to 2018. Among 1 169 441 infants in the national cohort, MV use decreased from 22.0% in 2008 to 18.5% in 2018, with an estimated 29 700 fewer ventilated infants and 142 000 fewer days of MV than expected during this period.

CONCLUSIONS AND RELEVANCE

These findings suggest that preterm respiratory support changed significantly from 2008 to 2018, with decreased use and duration of MV, increased use and duration of NIV, and an overall increase in respiratory support duration.