Severity of Bronchopulmonary Dysplasia and Neurodevelopmental Outcome at 2 and 5 Years Corrected Age.

OBJECTIVE: To evaluate the association between bronchopulmonary dysplasia (BPD) severity and risk of neurodevelopmental impairment (NDI) at 2 years and 5 years corrected age and to examine whether this association changes over time. STUDY DESIGN: This single-center retrospective cohort study included patients with a gestational age <30 weeks surviving to 36 weeks postmenstrual age, divided into groups according to BPD severity. NDI was defined as having cognitive or motor abilities below -1 SD, cerebral palsy, or a hearing or a visual impairment. The association was assessed using a multivariate logistic regression model analysis, adjusting for known confounders for NDI, and mixed-model analysis. RESULTS: Of the 790 surviving infants (15% diagnosed with mild BPD, 9% with moderate BPD, and 10% with severe BPD), 88% and 82% were longitudinally assessed at 2 years and 5 years corrected age, respectively. The mixed-model analysis showed a statistically significant increase in NDI at all levels of BPD severity compared with infants with no BPD, and a 5-fold increased risk in NDI was seen from 2 years to 5 years corrected age in all degrees of BPD severity. The strength of this association between NDI and BPD severity did not change over time. CONCLUSIONS: Increased BPD severity is associated with increased risk of NDI at both 2 years and 5 years corrected age. The absolute incidence of NDI increased significantly from 2 years to 5 years corrected age for all BPD severity categories, but this increased risk was similar at both time points in each category.

Prolonged Continuous Monitoring of Regional Lung Function in Infants with Respiratory Failure.

Rationale: Electrical impedance tomography (EIT) allows instantaneous and continuous visualization of regional ventilation and changes in end-expiratory lung volume at the bedside. There is particular interest in using EIT for monitoring in critically ill neonates and young children with respiratory failure. Previous studies have focused only on short-term monitoring in small populations. The feasibility and safety of prolonged monitoring with EIT in neonates and young children have not been demonstrated yet. Objectives: To evaluate the feasibility and safety of long-term EIT monitoring in a routine clinical setting and to describe changes in ventilation distribution and homogeneity over time and with positioning in a multicenter cohort of neonates and young children with respiratory failure. Methods: At four European University hospitals, we conducted an observational study (NCT02962505) on 200 patients with postmenstrual ages (PMA) between 25 weeks and 36 months, at risk for or suffering from respiratory failure. Continuous EIT data were obtained using a novel textile 32-electrode interface and recorded at 48 images/s for up to 72 hours. Clinicians were blinded to EIT images during the recording. EIT parameters and the effects of body position on ventilation distribution were analyzed offline. Results: The average duration of EIT measurements was 53 ± 20 hours. Skin contact impedance was sufficient to allow image reconstruction for valid ventilation analysis during a median of 92% (interquartile range, 77-98%) of examination time. EIT examinations were well tolerated, with minor skin irritations (temporary redness or imprint) occurring in 10% of patients and no moderate or severe adverse events. Higher ventilation amplitude was found in the dorsal and right lung areas when compared with the ventral and left regions, respectively. Prone positioning resulted in an increase in the ventilation-related EIT signal in the dorsal hemithorax, indicating increased ventilation of the dorsal lung areas. Lateral positioning led to a redistribution of ventilation toward the dependent lung in preterm infants and to the nondependent lung in patients with PMA > 37 weeks. Conclusions: EIT allows continuous long-term monitoring of regional lung function in neonates and young children for up to 72 hours with minimal adverse effects. Our study confirmed the presence of posture-dependent changes in ventilation distribution and their dependency on PMA in a large patient cohort. Clinical trial registered with www.clinicaltrials.gov (NCT02962505).

Restricted Ventilation Associated with Reduced Neurodevelopmental Impairment in Preterm Infants.

BACKGROUND AND OBJECTIVE: Restrictive use of invasive mechanical ventilation (IMV) in preterm infants reduces the risk of bronchopulmonary dysplasia (BPD). Our objective was to determine its effect on neurodevelopmental impairment (NDI) at 24 months' corrected age (CA). METHODS: This retrospective single-center cohort study included all patients with a gestational age <30 weeks born in 2004/2005 (epoch 1) and 2010/2011 (epoch 2). In epoch 2, we introduced a policy of restriction on IMV and liberalized the use of respiratory stimulants in the delivery room and neonatal intensive care. Data on patient characteristics, respiratory management, short-term outcomes, mortality, BPD, and NDI at 24 months' CA were collected. RESULTS: Four hundred and four preterm infants were included. Compared to those in epoch 1, infants in epoch 2 were less likely to be intubated and the duration of IMV was shorter. Other noninvasive adjuvant therapies such as caffeine, doxapram, and nasal ventilation were more often used during epoch 2. There was a trend to less BPD in epoch 2 compared to epoch 1 (17 vs. 23%, adjusted OR = 0.75, 95% CI: 0.48, 1.16). Mortality did not change over time. The combined outcome death or NDI at 24 months' CA was significantly lower in epoch 2 compared to epoch 1 (24.7 vs. 33.9%, adjusted OR = 0.71, 95% CI: 0.53, 0.97). CONCLUSIONS: Restricted use of IMV is feasible in preterm infants and might be associated with a reduced risk of the combined outcome death or NDI at 24 months' CA. Larger studies are needed to confirm these findings.

Doxapram Treatment for Apnea of Prematurity: A Systematic Review.

BACKGROUND: Apnea of prematurity (AOP) is a common complication of preterm birth, for which caffeine is the first treatment of choice. In case of persistent AOP, doxapram has been advocated as an additional therapy. OBJECTIVE: To identify and appraise all existing evidence regarding efficacy and safety of doxapram use for AOP in infants born before 34 weeks of gestational age. METHODS: All studies reporting on doxapram use for AOP were identified by searching electronic databases, references from relevant studies, and abstracts from the Societies for Pediatric Research. Two reviewers independently assessed study eligibility and quality, and extracted data on study design, patient characteristics, efficacy and safety outcomes. RESULTS: The randomized controlled trials showed less apnea during doxapram treatment when compared to placebo, but no difference in treatment effect when compared to theophylline. No serious adverse effects were reported. We identified 28 observational studies consisting mainly of cohort studies and case series (n = 1,994). There was considerable heterogeneity in study design and quality. Most studies reported a positive effect of doxapram on apnea rate. A few studies reported on long-term outcomes with conflicting results. A range of possible doxapram-related short-term adverse effects were reported, sometimes associated with the use of higher doses. CONCLUSION: Based on the limited number of studies and level of evidence, no firm conclusions on the efficacy and safety of doxapram in preterm infants can be drawn. For this reason, routine use cannot be recommended. A large multicenter randomized controlled trial is urgently needed to provide more conclusive evidence.

Long-Term Neurodevelopmental Outcome after Doxapram for Apnea of Prematurity.

BACKGROUND: Doxapram has been advocated as a treatment for persistent apnea of prematurity (AOP). OBJECTIVE: To evaluate the effect of doxapram on long-term neurodevelopmental outcome in preterm infants as its safety still needs to be established. METHODS: From a retrospective cohort of preterm infants with a gestational age (GA) <30 weeks and/or a birth weight <1,250 g, born between 2000 and 2010, infants treated with doxapram (n = 142) and a nontreated control group were selected (n = 284). Patient characteristics and clinical and neurodevelopmental outcome data at 24 months' corrected age were collected. Neurodevelopmental delay (ND) was defined as having a Mental or Psychomotor Developmental Index (MDI/PDI) <-1 standard deviation (SD), cerebral palsy, or a hearing or visual impairment. Odds ratios (OR) were calculated using multiple logistic regression analyses adjusting for potential confounders. RESULTS: Infants treated with doxapram had a lower GA compared to controls. The number of infants with a MDI or PDI <-1 SD was not different between the groups. The risk of the combined outcome death or ND was significantly lower in the doxapram group after adjusting for confounding factors (OR = 0.54, 95% CI: 0.37, 0.78). Doxapram-treated infants had a higher risk of bronchopulmonary dysplasia and patent ductus arteriosus, but a lower risk of spontaneous intestinal perforation. All other morbidities were not different between the groups. CONCLUSIONS: This study suggests that doxapram is not associated with an increased risk of ND. These findings need to be confirmed or refuted by a large, well-designed, placebo-controlled randomized trial.