Age at First Extubation Attempt and Death or Respiratory Morbidities in Extremely Preterm Infants.

OBJECTIVE: To describe the timing of first extubation in extremely preterm infants and explore the relationship between age at first extubation, extubation outcome, and death or respiratory morbidities. STUDY DESIGN: In this subanalysis of a multicenter observational study, infants with birth weights of 1250 g or less and intubated within 24 hours of birth were included. After describing the timing of first extubation, age at extubation was divided into early (within 7 days from birth) vs late (days of life 8-35), and extubation outcome was divided into success vs failure (reintubation within 7 days after extubation), to create 4 extubation groups: early success, early failure, late success, and late failure. Logistic regression analyses were performed to evaluate associations between the 4 groups and death or bronchopulmonary dysplasia, bronchopulmonary dysplasia among survivors, and durations of respiratory support and oxygen therapy. RESULTS: Of the 250 infants included, 129 (52%) were extubated within 7 days, 93 (37%) between 8 and 35 days, and 28 (11%) beyond 35 days of life. There were 93, 36, 59, and 34 infants with early success, early failure, late success, and late failure, respectively. Although early success was associated with the lowest rates of respiratory morbidities, early failure was not associated with significantly different respiratory outcomes compared with late success or late failure in unadjusted and adjusted analyses. CONCLUSIONS: In a contemporary cohort of extremely preterm infants, early extubation occurred in 52% of infants, and only early and successful extubation was associated with decreased respiratory morbidities. Predictors capable of promptly identifying infants with a high likelihood of early extubation success or failure are needed.

The Impact of Time Interval between Extubation and Reintubation on Death or Bronchopulmonary Dysplasia in Extremely Preterm Infants.

OBJECTIVE: To explore the relation between time to reintubation and death or bronchopulmonary dysplasia (BPD) in extremely preterm infants. STUDY DESIGN: This was a subanalysis from an ongoing multicenter observational study. Infants with birth weight ≤1250 g, requiring mechanical ventilation, and undergoing their first elective extubation were prospectively followed throughout hospitalization. Time to reintubation was defined as the time interval between first elective extubation and reintubation. Univariate and multivariate logistic regression analyses were performed to evaluate associations between time to reintubation, using different observation windows after extubation (24-hour intervals), and death/BPD (primary outcome) or BPD among survivors (secondary outcome). aORs were computed with and without the confounding effects of cumulative mechanical ventilation duration. RESULTS: Of 216 infants included for analysis, 103 (48%) were reintubated at least once after their first elective extubation. Reintubation was associated with lower gestational age/weight and greater morbidities compared with infants never reintubated. After adjusting for confounders, reintubation within observation windows ranging between 24 hours and 3 weeks postextubation was associated with increased odds of death/BPD (but not BPD among survivors), independent of the cumulative mechanical ventilation duration. Reintubation within 48 hours from extubation conferred higher risk-adjusted odds of death/BPD vs other observation windows. CONCLUSIONS: Although reintubation after elective extubation was independently associated with increased likelihood of death/BPD in extremely preterm infants, the greatest risk was attributable to reintubation within the first 48 hours postextubation. Prediction models capable of identifying the highest-risk infants may further improve outcomes.

Pulmonary Hypertension Associated with Hypoxic-Ischemic Encephalopathy-Antecedent Characteristics and Comorbidities.

OBJECTIVE: To determine the characteristics of term infants with persistent pulmonary hypertension of the newborn (PPHN) associated with moderate or severe hypoxic ischemic encephalopathy (HIE). METHODS: We compared infants with and without PPHN enrolled in 2 randomized trials of therapeutic hypothermia: the induced hypothermia trial of cooling to 33.5°C for 72 hours vs normothermia, and the "usual-care" arm (33.5°C for 72 hours) of the optimizing cooling trial. RESULTS: Among 303 infants with HIE from these 2 studies, 67 (22%) had PPHN and 236 (78%) did not. We compared infants with PPHN with those without PPHN. The proportion of patients treated with therapeutic hypothermia was similar in PPHN and no-PPHN groups (66% vs 65%). Medication use during resuscitation (58% vs 44%), acidosis after birth (pH: 7.0 ± 0.2 vs 7.1 ± 0.2), severe HIE (43% vs 28%), meconium aspiration syndrome (39% vs 7%), pulmonary hemorrhage (12% vs 3%), culture-positive sepsis (12% vs 3%), systemic hypotension (65% vs 28%), inhaled nitric oxide therapy (64% vs 3%), and extracorporeal membrane oxygenation (12% vs 0%) were more common in the PPHN group. Length of stay (26 ± 21 vs 16 ± 14 days) and mortality (27% vs 16%) were higher in the PPHN group. CONCLUSIONS: PPHN is common among infants with moderate/severe HIE and is associated with severe encephalopathy, lung disease, sepsis, systemic hypotension, and increased mortality. The prevalence of PPHN was not different between those infants receiving therapeutic hypothermia at 33.5°C in these 2 trials (44/197 = 22%) compared with infants receiving normothermia in the induced hypothermia trial (23/106 = 22%).

Markers of Successful Extubation in Extremely Preterm Infants, and Morbidity After Failed Extubation.

OBJECTIVES: To identify variables associated with successful elective extubation, and to determine neonatal morbidities associated with extubation failure in extremely preterm neonates. STUDY DESIGN: This study was a secondary analysis of the National Institute of Child Health and Human Development Neonatal Research Network's Surfactant, Positive Pressure, and Oxygenation Randomized Trial that included extremely preterm infants born at 240/7 to 276/7 weeks' gestation. Patients were randomized either to a permissive ventilatory strategy (continuous positive airway pressure group) or intubation followed by early surfactant (surfactant group). There were prespecified intubation and extubation criteria. Extubation failure was defined as reintubation within 5 days of extubation. RESULTS: Of 1316 infants in the trial, 1071 were eligible; 926 infants had data available on extubation status; 538 were successful and 388 failed extubation. The rate of successful extubation was 50% (188/374) in the continuous positive airway pressure group and 63% (350/552) in the surfactant group. Successful extubation was associated with higher 5-minute Apgar score, and pH prior to extubation, lower peak fraction of inspired oxygen within the first 24 hours of age and prior to extubation, lower partial pressure of carbon dioxide prior to extubation, and non-small for gestational age status after adjustment for the randomization group assignment. Infants who failed extubation had higher adjusted rates of mortality (OR 2.89), bronchopulmonary dysplasia (OR 3.06), and death/ bronchopulmonary dysplasia (OR 3.27). CONCLUSIONS: Higher 5-minute Apgar score, and pH prior to extubation, lower peak fraction of inspired oxygen within first 24 hours of age, lower partial pressure of carbon dioxide and fraction of inspired oxygen prior to extubation, and nonsmall for gestational age status were associated with successful extubation. Failed extubation was associated with significantly higher likelihood of mortality and morbidities. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00233324.