Diuretic Tolerance to Repeated-Dose Furosemide in Infants Born Very Preterm with Bronchopulmonary Dysplasia.

OBJECTIVES: To assess the presence and timing of furosemide diuretic tolerance in infants with bronchopulmonary dysplasia (BPD), and to determine if tolerance is modified by thiazide co-administration. STUDY DESIGN: We performed a retrospective cohort study among infants born very preterm with BPD exposed to repeated-dose furosemide for 72 hours, measuring net fluid balance (total intake minus total output) as a surrogate of diuresis in the 3 days before and after exposure. The primary comparison was the difference in fluid balance between the first and third 24 hours of furosemide exposure. We fit a general linear model for within-subject repeated measures of fluid balance over time, with thiazide co-administration as an interaction variable. Secondary analyses included an evaluation of weight trajectories over time. RESULTS: In 83 infants, median fluid balance ranged between + 43.6 and + 52.7 ml/kg/d in the 3 days prior to furosemide exposure. Fluid balance decreased to a median of + 29.1 ml/kg/d in the first 24 hours after furosemide, but then increased to +47.5 ml/kg/d by the third 24-hour interval, consistent with tolerance (P < .001). Thiazides did not modify the change in fluid balance during furosemide exposure for any time-period. Weight decreased significantly in the first 24 hours after furosemide and increased thereafter (P < .001). CONCLUSIONS: The net fluid balance response to furosemide decreases rapidly during repeated-dose exposures in infants with BPD, consistent with diuretic tolerance. Clinicians should consider this finding in the context of an infant's therapeutic goals. Further research efforts to identify safe and effective furosemide dosage strategies are needed.

Group B Streptococcus Infection in Extremely Preterm Neonates and Neurodevelopmental Outcomes at 2 Years.

BACKGROUND: This study was performed to determine the incidence of group B Streptococcus (GBS) disease among extremely preterm infants and assess to risk of death or neurodevelopmental impairment (NDI) at a corrected age of 18-26 months. METHODS: In this observational cohort study of infants enrolled in a multicenter registry, the incidence of GBS disease was assessed in infants born in 1998-2016 at 22-28 weeks' gestation and surviving for >12 hours. The composite outcome, death or NDI, was assessed in infants born in 1998-2014 at 22-26 weeks' gestation. Infection was defined as GBS isolation in blood or cerebrospinal fluid culture at ≤72 hours (early-onset disease [EOD]) or >72 hours (late-onset disease [LOD]) after birth. Using Poisson regression models, the outcome was compared in infants with GBS disease, infants infected with other pathogens, and uninfected infants. RESULTS: The incidence of GBS EOD (2.70/1000 births [95% confidence interval (CI), 2.15-3.36]) and LOD (8.47/1000 infants [7.45-9.59]) did not change significantly over time. The adjusted relative risk of death/NDI was higher among infants with GBS EOD than in those with other infections (adjusted relative risk, 1.22 [95% CI, 1.02-1.45]) and uninfected infants (1.44 [1.23-1.69]). Risk of death/NDI did not differ between infants with GBS LOD and comparator groups. GBS LOD occurred at a significantly later age than non-GBS late-onset infection. Among infants surviving >30 days, the risk of death was higher with GBS LOD (adjusted relative risk, 1.90 [95% CI, 1.36-2.67]), compared with uninfected infants. CONCLUSIONS: In a cohort of extremely preterm infants, the incidence of GBS disease did not change during the study period. The increased risk of death or NDI with GBS EOD, and of death among some infants with GBS LOD, supports the need for novel preventive strategies for disease reduction. CLINICAL TRIALS REGISTRATION: NCT00063063.

Loop Diuretics in Severe Bronchopulmonary Dysplasia: Cumulative Use and Associations with Mortality and Age at Discharge.

OBJECTIVES: To measure between-center variation in loop diuretic use in infants developing severe bronchopulmonary dysplasia (BPD) in US children's hospitals, and to compare mortality and age at discharge between infants from low-use centers and infants from high-use centers. STUDY DESIGN: We performed a retrospective cohort study of preterm infants at <32 weeks of gestational age with severe BPD. The primary outcome was cumulative loop diuretic use, defined as the proportion of days with exposure between admission and discharge. Infant characteristics associated with loop diuretic use at P < .10 were included in multivariable models to adjust for center differences in case mix. Hospitals were ranked from lowest to highest in adjusted use and dichotomized into low-use centers and high-use centers. We then compared mortality and postmenstrual age at discharge between the groups through multivariable analyses. RESULTS: We identified 3252 subjects from 43 centers. Significant variation between centers remained despite adjustment for infant characteristics, with use present in an adjusted mean range of 7.3% to 49.4% of days (P < .0001). Mortality did not differ significantly between the 2 groups (aOR, 0.98; 95% CI, 0.62-1.53; P = .92), nor did postmenstrual age at discharge (marginal mean, 47.3 weeks [95% CI, 46.8-47.9 weeks] in the low-use group vs 47.4 weeks [95% CI, 46.9-47.9 weeks] in the high-use group; P = .96). CONCLUSIONS: A marked variation in loop diuretic use for infants developing severe BPD exists among US children's hospitals, without an observed difference in mortality or age at discharge. More research is needed to provide evidence-based guidance for this common exposure.

Impact of Early-Onset Sepsis and Antibiotic Use on Death or Survival with Neurodevelopmental Impairment at 2 Years of Age among Extremely Preterm Infants.

OBJECTIVE: To evaluate the hypothesis that early-onset sepsis increases risk of death or neurodevelopmental impairment (NDI) among preterm infants; and that among infants without early-onset sepsis, prolonged early antibiotics alters risk of death/NDI. STUDY DESIGN: Retrospective cohort study of infants born at the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network centers (2006-2014) at 22-26 weeks of gestation and birth weight 401-1000 g. Early-onset sepsis defined as growth of a pathogen from blood or cerebrospinal fluid culture ≤72 hours after birth. Prolonged early antibiotics was defined as antibiotics initiated ≤72 hours and continued ≥5 days without culture-confirmed infection, necrotizing enterocolitis, or spontaneous perforation. Primary outcome was death before follow-up or NDI assessed at 18-26 months corrected age. Poisson regression was used to estimate adjusted relative risk (aRR) and CI for early-onset sepsis outcomes. A propensity score for receiving prolonged antibiotics was derived from early clinical factors and used to match infants (1:1) with and without prolonged antibiotic exposure. Log binomial models were used to estimate aRR for outcomes in matched infants. RESULTS: Among 6565 infants, those with early-onset sepsis had higher aRR (95% CI) for death/NDI compared with infants managed with prolonged antibiotics (1.18 [1.06-1.32]) and to infants without prolonged antibiotics (1.23 [1.10-1.37]). Propensity score matching was achieved for 4362 infants. No significant difference in death/NDI (1.04 [0.98-1.11]) was observed with or without prolonged antibiotics among the matched cohort. CONCLUSIONS: Early-onset sepsis was associated with increased risk of death/NDI among extremely preterm infants. Among matched infants without culture-confirmed infection, prolonged early antibiotic administration was not associated with death/NDI.

The Diagnosis of Bronchopulmonary Dysplasia in Very Preterm Infants. An Evidence-based Approach.

Rationale: Current diagnostic criteria for bronchopulmonary dysplasia rely heavily on the level and duration of oxygen therapy, do not reflect contemporary neonatal care, and do not adequately predict childhood morbidity.Objectives: To determine which of 18 prespecified, revised definitions of bronchopulmonary dysplasia that variably define disease severity according to the level of respiratory support and supplemental oxygen administered at 36 weeks' postmenstrual age best predicts death or serious respiratory morbidity through 18-26 months' corrected age.Methods: We assessed infants born at less than 32 weeks of gestation between 2011 and 2015 at 18 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network.Measurements and Main Results: Of 2,677 infants, 683 (26%) died or developed serious respiratory morbidity. The diagnostic criteria that best predicted this outcome defined bronchopulmonary dysplasia according to treatment with the following support at 36 weeks' postmenstrual age, regardless of prior or current oxygen therapy: no bronchopulmonary dysplasia, no support (n = 773); grade 1, nasal cannula ≤2 L/min (n = 1,038); grade 2, nasal cannula >2 L/min or noninvasive positive airway pressure (n = 617); and grade 3, invasive mechanical ventilation (n = 249). These criteria correctly predicted death or serious respiratory morbidity in 81% of study infants. Rates of this outcome increased stepwise from 10% among infants without bronchopulmonary dysplasia to 77% among those with grade 3 disease. A similar gradient (33-79%) was observed for death or neurodevelopmental impairment.Conclusions: The definition of bronchopulmonary dysplasia that best predicted early childhood morbidity categorized disease severity according to the mode of respiratory support administered at 36 weeks' postmenstrual age, regardless of supplemental oxygen use.

Maternal Black Race and Persistent Wheezing Illness in Former Extremely Low Gestational Age Newborns: Secondary Analysis of a Randomized Trial.

OBJECTIVE: To evaluate the relationship between maternal self-reported race/ethnicity and persistent wheezing illness in former high-risk, extremely low gestational age newborns, and to quantify the contribution of socioeconomic, environmental, and biological factors on this relationship. STUDY DESIGN: We assessed persistent wheezing illness determined at 18-24 months corrected (for prematurity) age in survivors of a randomized trial. Parents/caregivers were surveyed for wheeze and inhaled asthma medication use quarterly to 12 months, and at 18 and 24 months. We used multivariable analysis to evaluate the relationship of maternal race to persistent wheezing illness, and identified mediators for this relationship via formal mediation analysis. RESULTS: Of 420 infants (25.2 ± 1.2 weeks of gestation and 714 ± 166 g at birth, 57% male, 34% maternal black race), 189 (45%) had persistent wheezing illness. After adjustment for gestational age, birth weight, and sex, infants of black mothers had increased odds of persistent wheeze compared with infants of nonblack mothers (OR = 2.9, 95% CI 1.9, 4.5). Only bronchopulmonary dysplasia, breast milk diet, and public insurance status were identified as mediators. In this model, the direct effect of race accounted for 69% of the relationship between maternal race and persistent wheeze, whereas breast milk diet, public insurance status, and bronchopulmonary dysplasia accounted for 8%, 12%, and 10%, respectively. CONCLUSIONS: Among former high-risk extremely low gestational age newborns, infants of black mothers have increased odds of developing persistent wheeze. A substantial proportion of this effect is directly accounted for by race, which may reflect unmeasured environmental influences, and acquired and innate biological differences. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01022580.

The Randomized, Controlled Trial of Late Surfactant: Effects on Respiratory Outcomes at 1-Year Corrected Age.

OBJECTIVE: To determine the effects of late surfactant on respiratory outcomes determined at 1-year corrected age in the Trial of Late Surfactant (TOLSURF), which randomized newborns of extremely low gestational age (≤28 weeks' gestational age) ventilated at 7-14 days to late surfactant and inhaled nitric oxide vs inhaled nitric oxide-alone (control). STUDY DESIGN: Caregivers were surveyed in a double-blinded manner at 3, 6, 9, and 12 months' corrected age to collect information on respiratory resource use (infant medication use, home support, and hospitalization). Infants were classified for composite outcomes of pulmonary morbidity (no PM, determined in infants with no reported respiratory resource use) and persistent PM (determined in infants with any resource use in ≥3 surveys). RESULTS: Infants (n = 450, late surfactant n = 217, control n = 233) were 25.3 ± 1.2 weeks' gestation and 713 ± 164 g at birth. In the late surfactant group, fewer infants received home respiratory support than in the control group (35.8% vs 52.9%, relative benefit [RB] 1.28 [95% CI 1.07-1.55]). There was no benefit of late surfactant for No PM vs PM (RB 1.27; 95% CI 0.89-1.81) or no persistent PM vs persistent PM (RB 1.01; 95% CI 0.87-1.17). After adjustment for imbalances in baseline characteristics, relative benefit of late surfactant treatment increased: RB 1.40 (95% CI 0.89-1.80) for no PM and RB 1.24 (95% CI 1.08-1.42) for no persistent PM. CONCLUSION: Treatment of newborns of extremely low gestational age with late surfactant in combination with inhaled nitric oxide decreased use of home respiratory support and may decrease persistent pulmonary morbidity. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01022580.

Randomized Trial of Late Surfactant Treatment in Ventilated Preterm Infants Receiving Inhaled Nitric Oxide.

OBJECTIVE: To assess whether late surfactant treatment in extremely low gestational age (GA) newborn infants requiring ventilation at 7-14 days, who often have surfactant deficiency and dysfunction, safely improves survival without bronchopulmonary dysplasia (BPD). STUDY DESIGN: Extremely low GA newborn infants (GA ≤28 0/7 weeks) who required mechanical ventilation at 7-14 days were enrolled in a randomized, masked controlled trial at 25 US centers. All infants received inhaled nitric oxide and either surfactant (calfactant/Infasurf) or sham instillation every 1-3 days to a maximum of 5 doses while intubated. The primary outcome was survival at 36 weeks postmenstrual age (PMA) without BPD, as evaluated by physiological oxygen/flow reduction. RESULTS: A total of 511 infants were enrolled between January 2010 and September 2013. There were no differences between the treated and control groups in mean birth weight (701 ± 164 g), GA (25.2 ± 1.2 weeks), percentage born at GA <26 weeks (70.6%), race, sex, severity of lung disease at enrollment, or comorbidities of prematurity. Survival without BPD did not differ between the treated and control groups at 36 weeks PMA (31.3% vs 31.7%; relative benefit, 0.98; 95% CI, 0.75-1.28; P = .89) or 40 weeks PMA (58.7% vs 54.1%; relative benefit, 1.08; 95% CI, 0.92-1.27; P = .33). There were no between-group differences in serious adverse events, comorbidities of prematurity, or severity of lung disease to 36 weeks. CONCLUSION: Late treatment with up to 5 doses of surfactant in ventilated premature infants receiving inhaled nitric oxide was well tolerated, but did not improve survival without BPD at 36 or 40 weeks. Pulmonary and neurodevelopmental assessments are ongoing. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01022580.

Inhaled nitric oxide increases urinary nitric oxide metabolites and cyclic guanosine monophosphate in premature infants: relationship to pulmonary outcome.

OBJECTIVE: Inhaled nitric oxide (iNO) has been tested to prevent bronchopulmonary dysplasia (BPD) in premature infants, however, the role of cyclic guanosine monophosphate (cGMP) is not known. We hypothesized that levels of NO metabolites (NOx) and cGMP in urine, as a noninvasive source for biospecimen collection, would reflect the dose of iNO and relate to pulmonary outcome. STUDY DESIGN: Studies were performed on 125 infants who required mechanical ventilation at 7 to 14 days and received 24 days of iNO at 20-2 ppm. A control group of 19 infants did not receive iNO. RESULTS: In NO-treated infants there was a dose-dependent increase of both NOx and cGMP per creatinine (maximal 3.1- and 2-fold, respectively, at 10-20 ppm iNO) compared with off iNO. NOx and cGMP concentrations at both 2 ppm and off iNO were inversely related to severity of lung disease during the 1st month, and the NOx levels were lower in infants who died or developed BPD at term. NOx was higher in Caucasian compared with other infants at all iNO doses. CONCLUSION: Urinary NOx and cGMP are biomarkers of endogenous NO production and lung uptake of iNO, and some levels reflect the severity of lung disease. These results support a role of the NO-cGMP pathway in lung development.

Assessment of Corticosteroid Therapy and Death or Disability According to Pretreatment Risk of Death or Bronchopulmonary Dysplasia in Extremely Preterm Infants.

Importance: Meta-analyses suggest that corticosteroids may be associated with increased survival without cerebral palsy in infants at high risk of bronchopulmonary dysplasia (BPD) but are associated with adverse neurologic outcomes in low-risk infants. Whether this association exists in contemporary practice is uncertain because most randomized clinical trials administered corticosteroids earlier and at higher doses than currently recommended. Objective: To evaluate whether the pretreatment risk of death or grade 2 or 3 BPD at 36 weeks' postmenstrual age modified the association between postnatal corticosteroid therapy and death or disability at 2 years' corrected age in extremely preterm infants. Design, Setting, and Participants: This cohort study analyzed data on 482 matched pairs of infants from 45 participating US hospitals in the National Institute of Child Health and Human Development Neonatal Research Network Generic Database (GDB). Infants were included in the cohort if they were born at less than 27 weeks' gestation between April 1, 2011, and March 31, 2017; survived the first 7 postnatal days; and had 2-year death or developmental follow-up data collected between January 2013 and December 2019. Corticosteroid-treated infants were propensity score matched with untreated controls. Data were analyzed from September 1, 2019, to November 30, 2022. Exposure: Systemic corticosteroid therapy to prevent BPD that was initiated between day 8 and day 42 after birth. Main Outcomes and Measures: The primary outcome was death or moderate to severe neurodevelopmental impairment at 2 years' corrected age. The secondary outcome was death or moderate to severe cerebral palsy at 2 years' corrected age. Results: A total of 482 matched pairs of infants (mean [SD] gestational age, 24.1 [1.1] weeks]; 270 males [56.0%]) were included from 656 corticosteroid-treated infants and 2796 potential controls. Most treated infants (363 [75.3%]) received dexamethasone. The risk of death or disability associated with corticosteroid therapy was inversely associated with the estimated pretreatment probability of death or grade 2 or 3 BPD. The risk difference for death or neurodevelopmental impairment associated with corticosteroids decreased by 2.7% (95% CI, 1.9%-3.5%) for each 10% increase in the pretreatment risk of death or grade 2 or 3 BPD. This risk transitioned from estimated net harm to benefit when the pretreatment risk of death or grade 2 or 3 BPD exceeded 53% (95% CI, 44%-61%). For death or cerebral palsy, the risk difference decreased by 3.6% (95% CI, 2.9%-4.4%) for each 10% increase in the risk of death or grade 2 or 3 BPD and transitioned from estimated net harm to benefit at a pretreatment risk of 40% (95% CI, 33%-46%). Conclusions and Relevance: Results of this study suggested that corticosteroids were associated with a reduced risk of death or disability in infants at moderate to high pretreatment risk of death or grade 2 or 3 BPD but with possible harm in infants at lower risk.

Late administration of surfactant replacement therapy increases surfactant protein-B content: a randomized pilot study.

BACKGROUND: Surfactant dysfunction may contribute to the development of bronchopulmonary dysplasia (BPD) in persistently ventilated preterm infants. We conducted a multicenter randomized, blinded, pilot study to assess the safety and efficacy of late administration of doses of a surfactant protein-B (SP-B)-containing surfactant (calfactant) in combination with prolonged inhaled nitric oxide (iNO) in infants ≤1,000 g birth weight (BW). METHODS: We randomized 85 preterm infants ventilated at 7-14 d after birth to receive either late administration of surfactant (up to 5 doses) plus prolonged iNO or iNO alone. Large aggregate surfactant was isolated from daily tracheal aspirates (TAs) for measurement of SP-B content, total protein, and phospholipid (PL). RESULTS: Late administration of surfactant had minimal acute adverse effects. Clinical status as well as surfactant recovery and SP-B content in tracheal aspirate were transiently improved as compared to the controls; these effects waned after 1 d. The change in SP-B content with surfactant dosing was positively correlated with SP-B levels during treatment (r = 0.50, P = 0.02). CONCLUSION: Low SP-B values increased with calfactant administration, but the relationship of this response to SP-B levels suggests that degradation is a contributing mechanism for SP-B deficiency and surfactant dysfunction. We conclude that late therapy with surfactant in combination with iNO is safe and transiently increases surfactant SP-B content, possibly leading to improved short- and long-term respiratory outcomes.

Comparison of nasal intermittent positive pressure ventilation and bubble CPAP with an in-line high-frequency interrupter in a premature infant lung model.

INTRODUCTION: Noninvasive ventilation has become a staple in the care of premature infants. However, failure rates continue to be high in this population. Modifications to noninvasive support, such as nasal intermittent positive pressure ventilation (NIPPV), are used clinically to reduce such failure. Previous in vitro studies have shown improved CO2 clearance when superimposing high-frequency oscillations onto bubble continuous positive airway pressure (BCPAP). OBJECTIVE: To compare the CO2 clearance of NIPPV to BCPAP with an in-line high-frequency interrupter (HFI) in a premature infant lung model. METHODS: A premature infant lung model was connected to either a Dräger VN500 for delivery of NIPPV or a BCPAP device with superimposed high-frequency oscillations generated by an in-line HFI. Change in end-tidal CO2  (ETCO2 ) and mean airway pressure at the simulated trachea were measured and compared for both noninvasive modalities. RESULTS: Superimposing HF oscillations onto BCPAP with an in-line HFI resulted in improved CO2 clearance relative to BCPAP alone for all tested oscillation frequencies at all CPAP levels (p < 0.001). NIPPV also resulted in improved CO2  clearance relative to nasal CPAP (NCPAP) alone (p < 0.001). Among the tested settings, BCPAP with an in-line HFI resulted in decreased ETCO2 relative to BCPAP ranging from -14% to -36%, while NIPPV resulted in decreased ETCO2  relative to NCPAP ranging from -2% to -12%. CONCLUSION: Superimposing high-frequency oscillations onto BCPAP using a novel in-line HFI was found to be more effective at clearing CO2 than NIPPV in a premature infant lung model.

Strategies to prevent ventilator-associated pneumonia, ventilator-associated events, and nonventilator hospital-acquired pneumonia in acute-care hospitals: 2022 Update.

The purpose of this document is to highlight practical recommendations to assist acute care hospitals to prioritize and implement strategies to prevent ventilator-associated pneumonia (VAP), ventilator-associated events (VAE), and non-ventilator hospital-acquired pneumonia (NV-HAP) in adults, children, and neonates. This document updates the Strategies to Prevent Ventilator-Associated Pneumonia in Acute Care Hospitals published in 2014. This expert guidance document is sponsored by the Society for Healthcare Epidemiology (SHEA), and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America, the American Hospital Association, the Association for Professionals in Infection Control and Epidemiology, and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise.

Association between postmenstrual age and furosemide dosing practices in very preterm infants.

OBJECTIVE: Furosemide renal clearance is slow after very preterm (VP) birth and increases with postnatal maturation. We compared furosemide dose frequency and total daily dose between postmenstrual age (PMA) groups in VP infants. STUDY DESIGN: Observational cohort study of VP infants exposed to a repeated-dose course of furosemide in Pediatrix neonatal intensive care units (NICU) from 1997 to 2016. RESULTS: We identified 6565 furosemide courses among 4638 infants. There were no statistically significant differences between PMA groups on the odds of receiving more frequent furosemide dosing. Furosemide courses initiated at <28 weeks PMA were associated with a higher total daily dose than those initiated at a later PMA. CONCLUSIONS: Furosemide dosing practices in the NICU are similar across PMA groups, despite maturational changes in drug disposition. Research is needed to identify and test rational dosing strategies across the PMA spectrum for this commonly used but unproven pharmacotherapy.

Blanket temperature during therapeutic hypothermia and outcomes in hypoxic ischemic encephalopathy.

OBJECTIVE: Determine whether blanket temperatures during therapeutic hypothermia (TH) are associated with 18-22 month outcomes for infants with hypoxic ischemic encephalopathy (HIE). STUDY DESIGN: Retrospective cohort study of 181 infants with HIE who received TH in two randomized trials within the Neonatal Research Network. We defined summative blanket temperature constructs and evaluated for association with a primary composite outcome of death or moderate/ severe disability at 18-22 months. RESULTS: Each 0.5 °C above 33.5 °C in the mean of the highest quartile blanket temperature was associated with a 52% increase in the adjusted odds of death/ disability (aOR 1.52, 95% CI 1.09-2.11). Having >8 consecutive blanket temperatures above 33.5 °C rendered an aOR of death/disability of 5.04 in the first 24 h (95% CI 1.54-16.6) and 6.92 in the first 48 h (95% CI 2.20-21.8) of TH. CONCLUSIONS: Higher blanket temperature during TH may be an early, clinically useful biomarker of HIE outcome.

Preserved pressure delivery during high-frequency oscillation of bubble CPAP in a premature infant lung model with both normal and abnormal lung mechanics.

BACKGROUND: Bubble continuous positive airway pressure (BCPAP) generates pressure oscillations which are suggested to improve gas exchange through mechanisms similar to high frequency (HF) ventilation. In a previous in-vitro lung model with normal lung mechanics, significantly improved CO2 washout was demonstrated using an HF interrupter in the supply flow of a BCPAP system. The effect of HF with BCPAP on delivered airway pressure (Paw) has not been fully investigated in a lung model having abnormal pulmonary mechanics. OBJECTIVE: To measure Paw in an infant lung model simulating normal and abnormal pulmonary compliance and resistance while connected to a BCPAP system with superimposed HF oscillations created using an in-line flow interrupter. DESIGN/METHODS: A premature infant lung model with either: normal lung mechanics, compliance 1.0 ml/cm H2 O, airway resistance 56 cm H2 O/(L/s); or abnormal mechanics, compliance 0.5 ml/cm H2 O, airway resistance 136 cm H2 O/(L/s), was connected to BCPAP with HF at either 4, 6, 8, 10, or 12 Hz. Paw was measured at BCPAPs of 4, 6, and 8 cm H2 O and respiratory rates (RR) of 40, 60, and 80 breaths/min and 6.0 ml tidal volume. RESULTS: Mean Paw averaged over all five frequencies showed no significant change from non-oscillated levels at all BCPAPs and RRs for both lung models. Paw amplitudes (peak-to-trough) during oscillation were significantly greater than the non-oscillated levels by an average of 1.7 ± 0.5 SD and 2.6 ± 0.5 SD cm H2 O (p < .001) for the normal and abnormal models, respectively. CONCLUSIONS: HF oscillation of BCPAP using a flow interrupter did not alter mean delivered Paw compared to non-oscillated BCPAP for both normal and abnormal lung mechanics models. This simple modification to BCPAP may be a useful enhancement to this mode of non-invasive respiratory support.

Neurodevelopmental outcomes following neonatal late-onset sepsis and blood culture-negative conditions.

OBJECTIVE: Determine risk of death or neurodevelopmental impairment (NDI) in infants with late-onset sepsis (LOS) versus late-onset, antibiotic-treated, blood culture-negative conditions (LOCNC). DESIGN: Retrospective cohort study. SETTING: 24 neonatal centres. PATIENTS: Infants born 1/1/2006-31/12/2014, at 22-26 weeks gestation, with birth weight 401-1000 g and surviving >7 days were included. Infants with early-onset sepsis, necrotising enterocolitis, intestinal perforation or both LOS and LOCNC were excluded. EXPOSURES: LOS and LOCNC were defined as antibiotic administration for ≥5 days with and without a positive blood/cerebrospinal fluid culture, respectively. Infants with these diagnoses were also compared with infants with neither condition. OUTCOMES: Death or NDI was assessed at 18-26 months corrected age follow-up. Modified Poisson regression models were used to estimate relative risks adjusting for covariates occurring ≤7 days of age. RESULTS: Of 7354 eligible infants, 3940 met inclusion criteria: 786 (20%) with LOS, 1601 (41%) with LOCNC and 1553 (39%) with neither. Infants with LOS had higher adjusted relative risk (95% CI) for death/NDI (1.14 (1.05 to 1.25)) and death before follow-up (1.71 (1.44 to 2.03)) than those with LOCNC. Among survivors, risk for NDI did not differ between the two groups (0.99 (0.86 to 1.13)) but was higher for LOCNC infants (1.17 (1.04 to 1.31)) compared with unaffected infants. CONCLUSIONS: Infants with LOS had higher risk of death, but not NDI, compared with infants with LOCNC. Surviving infants with LOCNC had higher risk of NDI compared with unaffected infants. Improving outcomes for infants with LOCNC requires study of the underlying conditions and the potential impact of antibiotic exposure.

National and international guidelines for neonatal caffeine use: Are they evidenced-based?

The Caffeine for Apnea of Prematurity (CAP) trial showed that caffeine was safe when used with standard dosing and provided both pulmonary and neurological benefits to preterm infants. Since its publication almost 15 years ago, the use of caffeine in extremely premature infants in Newborn Intensive Care Units worldwide has increased, with almost all receiving the drug during their hospital stay. Subsequent observational studies suggested that administration of caffeine before 3 days of age may have greater benefits, leading many neonatologists to start caffeine prophylactically in all very low birth weight infants. Several publicly available national and international guidelines on caffeine advocate prophylactic use, and some recommend higher doses than those used in the CAP trial. This article will review the evidence basis for neonatal caffeine therapy in light of these guidelines.

Carbon dioxide clearance using bubble CPAP with superimposed high-frequency oscillations in a premature infant lung model with abnormal lung mechanics.

BACKGROUND: High-frequency (HF) oscillatory ventilation has been shown to improve carbon dioxide (CO2 ) clearance in premature infants. In a previous in vitro lung model with normal lung mechanics we demonstrated significantly improved CO2 washout by HF oscillation of bubble continuous positive airway pressure (BCPAP). OBJECTIVE: To examine CO2 clearance in a premature infant lung model with abnormal lung mechanics via measurement of end-tidal CO2 levels (EtCO2 ) while connected to HF oscillated BCPAP. DESIGN AND METHODS: A 40 mL premature infant lung model with either: normal lung mechanics (NLM): compliance 1.0 mL/cm H2 O, airway resistance 56 cm H2 O/(L/s); or abnormal lung mechanics (ALM): compliance 0.5 mL/cm H2 O, airway resistance 136 cm H2 O/(L/s), was connected to BCPAP with HF oscillation at either 4, 6, 8, 10, or 12 Hz. EtCO2 was measured at BCPAPs of 4, 6, and 8 cm H2 O and respiratory rates (RR) of 40, 60, and 80 breaths/min and 6 mL tidal volume. RESULTS: HF oscillation decreased EtCO2 levels at all BCPAPs, RRs, and oscillation frequencies for both lung models. Overall mean ± SD EtCO2 levels decreased (P < .001) from nonoscillated baseline by 19.3 ± 10.2% for NLM vs 14.1 ± 8.8% for ALM. CO2 clearance improved for both lung models (P < .001) as a function of oscillation frequency and RR with greatest effectiveness at 40 to 60 breaths/min and HF at 8 to 12 Hz. CONCLUSIONS: In this in vitro premature infant lung model, HF oscillation of BCPAP was associated with improved CO2 clearance as compared with nonoscillated BCPAP for both NLM and ALM. The significant improvement in CO2 clearance in an abnormal lung environment is an important step towards clinical testing of this novel respiratory support modality.

Variation in Car Seat Tolerance Screen Performance in Newborn Nurseries.

BACKGROUND: Currently, car seat tolerance screens (CSTSs) are recommended for all infants born prematurely in the United States. Although many late-preterm infants are cared for exclusively in newborn nurseries (NBNs), data on implementation of CSTS in nurseries are limited. Our objective for this study was to determine management strategies and potential variation in practice of CSTS in NBNs across the nation. METHODS: We surveyed NBNs across 35 states using the Better Outcomes through Research for Newborns (BORN) network to determine what percentage perform CSTSs, inclusion and failure criteria, performance characteristics, follow-up of failed CSTSs including use of car beds, and provider attitudes toward CSTS. RESULTS: Of the 84 NBNs surveyed, 90.5% performed predischarge CSTSs. The most common failure criteria were saturation <90%, bradycardia <80 beats per minute, and apnea >20 seconds. More than 55% noted hypotonia as an additional inclusion criterion for testing, and >34% tested any infant who had ever required supplemental oxygen. After an initial failed CSTS, >93% of NBNs retested in a car seat at a future time point, whereas only ∼1% automatically discharged infants in a car bed. When asked which infants should undergo predischarge CSTS, the most common recommendations by survey respondents included infants with hypotonia (83%), airway malformations (78%), hemodynamically significant congenital heart disease (63%), and prematurity (61%). CONCLUSIONS: There is a large degree of variability in implementation of CSTS in NBNs across the United States. Further guidance on screening practices and failure criteria is needed to inform future practice and policy.