CPAP Versus NIPPV Postextubation in Preterm Neonates: A Comparative-Effectiveness Study

BACKGROUND AND OBJECTIVES

Nasal intermittent positive pressure ventilation (NIPPV) has been shown to be superior to nasal continuous positive airway pressure (CPAP) postextubation in preterm neonates. However, studies have not permitted high CPAP pressures or rescue with other modes. We hypothesized that if CPAP pressures >8 cmH2O and rescue with other modes were permitted, CPAP would be noninferior to NIPPV.

METHODS

We conducted a pragmatic, comparative-effectiveness, noninferiority study utilizing network-based real-world data from 22 Canadian NICUs. Centers self-selected CPAP or NIPPV as their standard postextubation mode for preterm neonates <29 weeks' gestation. The primary outcome was failure of the initial mode ≤72 hours. Secondary outcomes included failure ≤7 days, and reintubation ≤72 hours and ≤7 days. Groups were compared using a noninferiority adjusted risk-difference (aRD) margin of 0.05, and margin of no difference.

RESULTS

A total of 843 infants extubated to CPAP and 974 extubated to NIPPV were included. CPAP was not noninferior (and inferior) to NIPPV for failure of the initial mode ≤72 hours (33.0% vs 26.3%; aRD 0.07 [0.03 to 0.12], Pnoninferiority(NI) = .86), and ≤7 days (40.7% vs 35.8%; aRD 0.09 [0.05 to 0.13], PNI = 0.97). However, CPAP was noninferior (and equivalent) to NIPPV for reintubation ≤72 hours (13.2% vs 16.1%; aRD 0.01 [-0.05 to 0.02], PNI < .01), and noninferior (and superior) for reintubation ≤7 days (16.4% vs 22.8%; aRD -0.04 [-0.07 to -0.001], PNI < .01).

CONCLUSIONS

CPAP was not noninferior to NIPPV for failure ≤72 hours postextubation; however, it was noninferior to NIPPV for reintubation ≤72 hours and ≤7 days. This suggests CPAP may be a reasonable initial postextubation mode if alternate rescue strategies are available.

Clinical burden associated with therapies for cardio-pulmonary critical decompensation in preterm neonates across Canadian neonatal intensive care units

The aim of this retrospective cohort study was to study the clinical burden associated with cardio-pulmonary critical decompensations (CPCDs) in preterm neonates and factors associated with mortality. Through the Canadian Neonatal Network (30 tertiary NICUs, 2010-2017), we identified infants < 32-week gestational age with CPCDs, defined by "significant exposure" to cardiotropes and/or inhaled nitric oxide (iNO): (1) either therapy for ≥ 3 consecutive days, (2) both for ≥ 2 consecutive days, or (3) any exposure within 2 days of death. Early CPCDs (≤ 3 days of age) and late CPCDs (> 3 days) were examined separately. Outcomes included CPCD-incidence, mortality, and inter-site variability using standardized ratios (observed/adjusted expected rate) and network funnel plots. Mixed-effects analysis was used to quantify unit-level variability in mortality. Overall, 10% of admissions experienced CPCDs (n = 2915). Late CPCDs decreased by ~ 5%/year, while early CPCDs were unchanged during the study period. Incidence and CPCD-associated mortality varied between sites, for both early (0.6-7.5% and 0-100%, respectively) and late CPCDs (2.5-15% and 14-83%, respectively), all p < 0.01. Units' late-CPCD incidence and mortality demonstrated an inverse relationship (slope =  -2.5, p < 0.01). Mixed-effects analysis demonstrated clustering effect, with 6.4% and 8.6% of variability in mortality after early and late CPCDs respectively being site-related, unexplained by available patient-level characteristics or unit volume. Mortality was higher with combined exposure than with only-cardiotropes or only-iNO (41.3%, 24.8%, 21.5%, respectively; p < 0.01).

CONCLUSIONS

Clustering effects exist in CPCD-associated mortality among Canadian NICUs, with higher incidence units showing lower mortality. These data may aid network-level benchmarking, patient-level risk stratification, parental counseling, and further research and quality improvement work.

WHAT IS KNOWN

• Preterm neonates remain at high risk of acute and chronic complications; the most critically unwell require therapies such as cardiotropic drugs and inhaled nitric oxide. • Infants requiring these therapies are known to be at high risk for adverse neonatal outcomes and for mortality.

WHAT IS NEW

• This study helps illuminate the national burden of acute cardio-pulmonary critical decompensation (CPCD), defined as the need for cardiotropic drugs or inhaled nitric oxide, and highlights the high risk of morbidity and mortality associated with this disease state. • Significant nationwide variability exists in both CPCD incidence and associated mortality; a clustering effect was observed with higher incidence sites showing lower CPCD-associated mortality.

Neurodevelopmental outcomes of singleton large for gestational age infants <29 weeks' gestation: a retrospective cohort study

OBJECTIVE

To compare neurodevelopmental outcomes of large and appropriate for gestational age (LGA, AGA) infants <29 weeks' gestation at 18-24 months of corrected age.

STUDY DESIGN

Retrospective cohort study using the Canadian Neonatal Network and Canadian Neonatal Follow-Up Network databases. Primary outcome was a composite of death or significant neurodevelopmental impairment (NDI), defined as severe cerebral palsy, Bayley III cognitive, language and motor scores of <70, need for hearing aids or cochlear implant and bilateral visual impairment. Univariate and multivariable logistic analyses were applied for outcomes.

RESULTS

The study cohort comprised 170 LGA and 1738 AGA infants. There was no difference in significant NDI or individual components of the Bayley III between LGA and AGA groups. LGA was associated with the increased risk of death by follow-up, 44/170 (25.9%) vs. 320/1738 (18.4%) (aOR: 1.60 95% CI: 1.00-2.54).

CONCLUSIONS

Risk of NDI was similar between LGA and AGA infants.

Severe Neurodevelopmental Impairment in Neonates Born Preterm: Impact of Varying Definitions in a Canadian Cohort

OBJECTIVE

To assess the impact of variations in the definition of severe neurodevelopmental impairment (NDI) on the incidence of severe NDI and the association with risk factors using the Canadian Neonatal Follow-Up Network cohort.

STUDY DESIGN

Literature review of severe NDI definitions and application of these definitions were performed in this database cohort study. Infants born at 23-28 completed weeks of gestation between 2009 and 2011 (n = 2187) admitted to a Canadian Neonatal Network neonatal intensive care unit and assessed at 21 months' corrected age were included. The incidence of severe NDI, aORs, and 95% CIs were calculated to express the relationship between risk factors and severe NDI using the definitions with the highest and the lowest incidence rates of severe NDI.

RESULTS

The incidence of severe NDI ranged from 3.5% to 14.9% (highest vs lowest rate ratio 4.29; 95% CI 3.37-5.47). The associations between risk factors and severe NDI varied depending on the definition used. Maternal ethnicity, employment status, antenatal corticosteroid treatment, and gestational age were not associated consistently with severe NDI. Although maternal substance use, sex, score of neonatal acute physiology >20, late-onset sepsis, bronchopulmonary dysplasia, and brain injury were consistently associated with severe NDI irrespective of definition, the strength of the associations varied.

CONCLUSIONS

The definition of severe NDI significantly influences the incidence and the associations between risk factors and severe NDI. A standardized definition would facilitate site comparisons and scientific communication.

Neurodevelopmental Outcomes of Infants Born at <29 Weeks of Gestation Admitted to Canadian Neonatal Intensive Care Units Based on Location of Birth

OBJECTIVE

To compare mortality and neurodevelopmental outcomes of outborn and inborn preterm infants born at <29 weeks of gestation admitted to Canadian neonatal intensive care units (NICUs).

STUDY DESIGN

Data were obtained from the Canadian Neonatal Network and Canadian Neonatal Follow-up Network databases for infants born at <29 weeks of gestation admitted to NICUs from April 2009 to September 2011. Rates of death, severe neurodevelopmental impairment (NDI), and overall NDI were compared between outborn and inborn infants at 18-21 months of age, corrected for prematurity.

RESULTS

Of 2951 eligible infants, 473 (16%) were outborn. Mean birth weight (940 ± 278 g vs 897 + 237 g), rates of treatment with antenatal steroids (53.9% vs 92.9%), birth weight small for gestational age (5.3% vs 9.4%), and maternal college education (43.7% vs 53.9%) differed between outborn and inborn infants, respectively (all P values <.01). The median Score for Neonatal Acute Physiology-II (P = .01) and Apgar score at 5 minutes (P < .01) were higher in inborn infants. Severe brain injury was more common among outborn infants (25.3% vs 14.7%, P < .01). Outborn infants had higher odds of death or severe NDI (aOR 1.7, 95% CI 1.3-2.2), death or overall NDI (aOR 1.6, 95% CI 1.2-2.2), death (aOR 2.1, 95% CI 1.5-3.0), and cerebral palsy (aOR 1.9, 95% CI 1.1-3.3).

CONCLUSIONS

The composite outcomes of death or neurodevelopmental impairment were significantly higher in outborn compared with inborn infants admitted to Canadian NICUs. Adverse outcomes were mainly attributed to increased mortality and cerebral palsy in outborn neonates.

The role of antenatal corticosteroids in twin pregnancies complicated by preterm birth

BACKGROUND

Data regarding the effects of antenatal corticosteroids in twin pregnancies are limited because of the insufficient number of women with twins enrolled in randomized controlled trials on antenatal corticosteroids. Furthermore, the interpretation of available data is limited by the fact that the interval from the administration of antenatal corticosteroids to delivery is greater than 7 days in a large proportion of twins, a factor that has been shown to affect the efficacy of antenatal corticosteroids and has not been controlled for in previous studies.

OBJECTIVE

The objective of the study was to compare neonatal mortality and morbidity in preterm twins receiving a complete course of antenatal corticosteroids 1-7 days before birth to those who did not receive antenatal corticosteroids and to compare these outcome effects with those observed in singletons.

STUDY DESIGN

We performed a retrospective cohort study using data collected on singleton and twin neonates born between 24(0/7) and 33(6/7) weeks' gestational age and were admitted to tertiary neonatal units in Canada between 2010 and 2014. A comparison of neonatal outcomes between twin neonates who received a complete course of antenatal corticosteroids 1-7 days before birth (n = 1758) and those who did not receive antenatal corticosteroids (n = 758) and between singleton neonates who received a complete course of antenatal corticosteroids 1-7 days before birth (n = 4638) and those did not receive antenatal corticosteroids (n = 2312) was conducted after adjusting for gestational age, sex, hypertension, outborn status, small for gestational age, parity, and cesarean birth. Adjusted odds ratios and 95% confidence intervals for various neonatal outcomes were calculated.

RESULTS

Administration of a complete course of antenatal corticosteroids within 1-7 days before birth in both twins and singletons was associated with similar reduced odds of neonatal death (for twins adjusted odds ratio 0.42 [95% confidence interval, 0.24-0.76] and for singletons adjusted odds ratios, 0.38 [95% confidence interval, 0.28-0.50]; P = .7 for comparison of twins vs singletons), mechanical ventilation (for twins adjusted odds ratio, 0.47 [95% confidence interval, 0.35-0.63] and for singletons adjusted odds ratio, 0.47 [95% confidence interval, 0.41-0.55]; P = .9), respiratory distress syndrome (for twins adjusted odds ratio, 0.53 [95% confidence interval, 0.40-0.69], and for singletons adjusted odds ratio, 0.54 [95% confidence interval, 0.47-0.62]; P = .9) and severe neurological injury (for twins adjusted odds ratio, 0.50 [95% confidence interval, 0.30-0.83] and for singletons adjusted odds ratio, 0.45 [95% confidence interval, 0.34-0.59]; P = .7). Administration of a complete course of antenatal corticosteroids was not associated with a reduced odds of bronchopulmonary dysplasia, severe retinopathy of prematurity, or necrotizing enterocolitis in both twins and singletons.

CONCLUSION

Administration of a complete course of antenatal corticosteroids 1-7 days before birth in twin pregnancies is associated with a clinically significant decrease in neonatal mortality, short-term respiratory morbidity, and severe neurological injury that is similar in magnitude to that observed among singletons.