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.

Rates and Determinants of Home Nasogastric Tube Feeding in Infants Born Very Preterm

OBJECTIVE

To examine rates and determinants of home nasogastric (NG)-tube feeding at hospital discharge in a cohort of very preterm infants within the Canadian Neonatal Network (CNN).

STUDY DESIGN

This was a population-based cohort study of infants born <33 weeks of gestation and admitted to neonatal intensive care units (NICUs) participating in the CNN between January 1, 2010, and December 31, 2018. We excluded infants who had major congenital anomalies, required gastrostomy-tube, or were discharged to non-CNN facilities. Multivariable logistic regression analysis was used to identify independent determinants of home NG-tube feeding at hospital discharge.

RESULTS

Among the 13 232 infants born very preterm during the study period, 333 (2.5%) were discharged home to receive NG-tube feeding. Rates of home NG-tube feeding varied across Canadian NICUs, from 0% to 12%. Determinants of home NG-tube feeding were gestational age (aOR 0.94 per each gestational week increase, 95% CI 0.88-0.99); duration of mechanical ventilation (aOR 1.02 per each day increase, 95% CI 1.01-1.02); high illness severity at birth (aOR 1.32, 95% CI 1.01-1.74); small for gestational age (aOR 2.06, 95% CI 1.52-2.78); male sex (aOR 0.61, 95% CI 0.49-0.77); severe brain injury (aOR 1.60, 95% CI 1.10-2.32); and bronchopulmonary dysplasia (aOR 2.22, 95% CI 1.67-2.94).

CONCLUSIONS

Rates of home NG-tube feeding varied widely between Canadian NICUs. Higher gestational age and male sex reduced the odds of discharge home to receive NG-tube feeding; and in contrast small for gestational age, severe brain injury, prolonged duration on mechanical ventilation and bronchopulmonary dysplasia increased the odds.

50 Poractant alfa versus bovine lipid extract surfactant for respiratory distress syndrome in preterm infants: A prospective comparative effectiveness cohort study

Primary Subject area

Neonatal-Perinatal Medicine

Background

There is a paucity of comparative effectiveness data for bovine lipid extract surfactant (BLES) and poractant alfa (Curosurf).

Objectives

To compare duration of respiratory support and short-term outcomes in very preterm infants treated with bovine lipid extract surfactant and poractant alfa.

Design/Methods

We performed a prospective, multicentre, comparative effectiveness study. Thirteen Canadian level III neonatal intensive care units (NICUs) provided bovine lipid extract surfactant to infants born &lt;32 weeks’ gestational age (GA) for a set period of time in the year 2019 (3 to 9 months), then changed to poractant alfa for the remainder of the year. The primary outcome was total duration of respiratory support (invasive and non-invasive). We utilized the Canadian Neonatal Network database for all study data.

Results

A total of 968 eligible infants (530 infants &lt; 28 weeks’ GA and 438 infants 280-316weeks’ GA) were included, of which 494 received bovine lipid extract surfactant and 474 received poractant alfa. In unadjusted analysis, no difference was observed in total duration of any respiratory support (median 38 vs. 40.5 days). After adjusting for baseline characteristics and accounting for cluster effects, infants treated with poractant alfa spent a median of 4.16 fewer days on respiratory support (95% CI 0.05, 8.28 days). This reduction was observed in the subgroup of infants 280-316 weeks’ GA, but not in those &lt; 28 weeks’ GA, and was explained by their shorter time on non-invasive respiratory support. No differences were observed in the need to re-dose surfactant, hospital mortality, bronchopulmonary dysplasia, or length of stay in NICU.

Conclusion

Administration of poractant alfa was associated with shorter median duration of respiratory support compared to bovine lipid extract surfactant in preterm neonates &lt; 32 weeks’ GA.

Relative effectiveness and safety of pharmacotherapeutic agents for patent ductus arteriosus (PDA) in preterm infants: a protocol for a multicentre comparative effectiveness study (CANRxPDA)

INTRODUCTION

Patent ductus arteriosus (PDA) is the most common cardiovascular problem that develops in preterm infants and evidence regarding the best treatment approach is lacking. Currently available medical options to treat a PDA include indomethacin, ibuprofen or acetaminophen. Wide variation exists in PDA treatment practices across Canada. In view of this large practice variation across Canadian neonatal intensive care units (NICUs), we plan to conduct a comparative effectiveness study of the different pharmacotherapeutic agents used to treat the PDA in preterm infants.

METHODS AND ANALYSIS

A multicentre prospective observational comparative-effectiveness research study of extremely preterm infants born <29 weeks gestational age with an echocardiography confirmed PDA will be conducted. All participating sites will self-select and adhere to one of the following primary pharmacotherapy protocols for all preterm babies who are deemed to require treatment.Standard dose ibuprofen (10 mg/kg followed by two doses of 5 mg/kg at 24 hours intervals) irrespective of postnatal age (oral/intravenous).Adjustable dose ibuprofen (oral/intravenous) (10 mg/kg followed by two doses of 5 mg/kg at 24 hours intervals if treated within the first 7 days after birth. Higher doses of ibuprofen up to 20 mg/kg followed by two doses of 10 mg/kg at 24 hours intervals if treated after the postnatal age cut-off for lower dose as per the local centre policy).Acetaminophen (oral/intravenous) (15 mg/kg every 6 hours) for 3-7 days.Intravenous indomethacin (0.1-0.3 mg/kg intravenous every 12-24 hours for a total of three doses).

OUTCOMES

The primary outcome is failure of primary pharmacotherapy (defined as need for further medical and/or surgical/interventional treatment following an initial course of pharmacotherapy). The secondary outcomes include components of the primary outcome as well as clinical outcomes related to response to treatment or adverse effects of treatment.

SITES AND SAMPLE SIZE

The study will be conducted in 22 NICUs across Canada with an anticipated enrollment of 1350 extremely preterm infants over 3 years.

ANALYSIS

To examine the relative effectiveness of the four treatment strategies, the primary outcome will be compared pairwise between the treatment groups using χ² test. Secondary outcomes will be compared pairwise between the treatment groups using χ² test, Student's t-test or Wilcoxon rank sum test as appropriate. To further examine differences in the primary and secondary outcomes between the four groups, multiple logistic or linear regression models will be applied for each outcome on the treatment groups, adjusted for potential confounders using generalised estimating equations to account for within-unit-clustering. As a sensitivity analysis, the difference in the primary and secondary outcomes between the treatment groups will also be examined using propensity score method with inverse probability weighting approach.

ETHICS AND DISSEMINATION

The study has been approved by the IWK Research Ethics Board (#1025627) as well as the respective institutional review boards of the participating centres.

TRIAL REGISTRATION NUMBER

NCT04347720.

Early-onset neonatal sepsis: Organism patterns between 2009 and 2014

OBJECTIVE

To evaluate trends in organisms causing early-onset neonatal sepsis (EONS). Congruent with recent reports, we hypothesized there would be an increase in EONS caused by Escherichia coli.

STUDY DESIGN

National data on infants admitted to neonatal intensive care units from 2009 to 2014 were compared to previously reported data from 2003 to 2008. We report 430 cases of EONS from 2009 to 2014. Bivariate analyses were used to analyze the distribution of causative organisms over time and differences by gestational age. Linear regression was used to estimate trends in causative organisms.

RESULTS

Since 2003, there has been a trend of increasing numbers of cases caused by E coli (P<0.01). The predominant organism was E coli in preterm infants and Group B Streptococcus in term infants.

CONCLUSIONS

With the majority of EONS cases now caused by E coli, our findings emphasize the importance of continued surveillance of causative organism patterns and developing approaches to reduce cases caused by E coli.

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.

Children hospitalized with respiratory syncytial virus infection in Saskatchewan pediatric tertiary care centers, 2002-2005

OBJECTIVE

To describe the epidemiology and severity of illness of children hospitalized with respiratory syncytial virus (RSV) infection, including those who received palivizumab prophylaxis, at Royal University Hospital (RUH), Saskatoon and Regina General Hospital (RGH) from July 2002 to June 2005.

METHODS

Children hospitalized for &ge; 24 hours with laboratory-confirmed RSV infection were enrolled, and their health records were retrospectively reviewed for patient demographics and referral patterns, use of palivizumab prophylaxis, severity of infection (length of hospitalization, need for and duration of pediatric intensive care and mechanical ventilation) and outcome of infection.

RESULTS

A total of 590 children (324 males) were hospitalized over the three years. The median chronological age at admission was 5.3 months, and median hospital stay was 4.0 days. Gestational age at birth was &ge; 36 weeks in 82.4% of patients. RSV disease severity was mild to moderate in 478 patients (81.0%) and severe in 110 (18.6%). Thirty-nine patients (6.6%) required pediatric intensive care unit admission, for a median of 5.0 days. Twenty-two of these patients (56%) were mechanically ventilated for a median of 6.0 days. Two children died, not attributed to RSV infection. Twenty-two patients had received palivizumab prophylaxis before hospital admission, with 18 completing at least 2 of the monthly doses. Most of these children (17/22) had mild to moderate illness.

CONCLUSIONS

RSV causes significant morbidity in Saskatchewan, affecting predominantly term infants. The majority of illness is mild to moderate. Some patients who have received palivizumab may still develop significant RSV disease.

Sighs and their relationship to apnea in the newborn infant

To test the hypothesis that sighs are mechanistically important in triggering apnea, we studied 10 preterm infants, group 1: body weight 1.8 +/- 0.1 kg, gestational age 33 +/- 1 weeks, postnatal age 21 +/- 4 days, and 10 term infants, group 2: body weight 3.9 +/- 0.15 kg, gestational age 40 +/- 0.4 weeks, postnatal age 1.4 +/- 0.2 days. Instantaneous ventilatory changes associated with a sigh were studied in another 10 preterm infants, group 3: body weight 1.6 +/- 0.11 kg, gestational age 32 +/- 0.4 weeks, postnatal age 25 +/- 4 days. Ventilation was measured using a nosepiece and a flow-through system. Sleep states were recorded. Sighs were more frequent in preterm than in term infants (0.4 +/- 0.04 vs. 0.18 +/- 0.03 sighs/min; p = 0.03) and in rapid eye movement than in quiet sleep (0.5 +/- 0.05 vs. 0.3 +/- 0.05 sighs/min; p = 0.05). Of 722 apneas, 235 (33%) were associated with a sigh; of these, 113 (48%) preceded and 122 (52%) followed a sigh. Sighs induced with airway occlusion (groups 1 and 2) were more frequent after occlusion on 21 than on 35% O2, particularly when O2 saturation was low and negative airway pressure high. Instantaneous ventilation measured over 10 breaths preceding a sigh did not show any trend indicating the possible appearance of a sigh. Tidal volume increased from 7.5 +/- 0.7 before the sigh to 18.9 +/- 0.7 ml/kg (p < 0.01) during a sigh, with a significant increase in inspiratory drive. Ventilation increased from 0.327 +/- 0.041 to 0.660 +/- 0.073 l/min/kg.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of a single breath of 100% oxygen on respiration in neonates during sleep

To determine the effect of a single breath of 100% O2 on ventilation, 10 full-term [body wt 3,360 +/- 110 (SE) g, gestational age 39 +/- 0.4 wk, postnatal age 3 +/- 0.6 days] and 10 preterm neonates (body wt 2,020 +/- 60 g, gestational age 34 +/- 2 wk, postnatal age 9 +/- 2 days) were studied during active and quiet sleep states. The single-breath method was used to measure peripheral chemoreceptor response. To enhance response and standardize the control period for all infants, fractional inspired O2 concentration was adjusted to 16 +/- 0.6% for a control O2 saturation of 83 +/- 1%. After 1 min of control in each sleep state, each infant was given a single breath of O2 followed by 21% O2. Minute ventilation (VE), tidal volume (VT), breathing frequency (f), alveolar O2 and CO2 tension, O2 saturation (ear oximeter), and transcutaneous O2 tension were measured. VE always decreased with inhalation of O2 (P less than 0.01). In quiet sleep, the decrease in VE was less in full-term (14%) than in preterm (40%) infants (P less than 0.001). Decrease in VE was due primarily to a drop in VT in full-term infants as opposed to a fall in f and VT in preterm infants (P less than 0.05). Apnea, as part of the response, was more prevalent in preterm than in full-term infants. In active sleep the decrease in VE was similar both among full-term (19%) and preterm (21%) infants (P greater than 0.5). These results suggest greater peripheral chemoreceptor response in preterm than in full-term infants, reflected by a more pronounced decrease in VE with O2. The results are compatible with a more powerful peripheral chemoreceptor contribution to breathing in preterm than in full-term infants.