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Rationale: Aerosolized albuterol is widely used, but its tolerability and efficacy in infants with severe bronchopulmonary dysplasia (sBPD) is not well established., Objectives: To compare the tolerability and efficacy of two dose levels of aerosolized albuterol to saline placebo in infants with sBPD., Methods: Single-center, multiple-crossover trial in 24 ventilated very preterm infants with sBPD. Albuterol (1.25 mg, 2.5 mg) and 3 ml of normal saline were administered every 4 h during separate 24-h treatment periods assigned in random order with a 6-h washout phase between periods. The primary outcome was the absolute change (post and pretherapy) in expiratory flow at 75% of exhalation (EF75). Secondary endpoints were changes in ventilator parameters, vital signs, and heart arrhythmia., Results: Average within subject EF75 values improved with each therapy: saline placebo ( + 0.45 L/min ± 2.5, p = .04), 1.25 mg of albuterol ( + 0.70 L/min ± 2.4, p < .001), and 2.5 mg of albuterol ( + 0.38 L/min ± 2.4, p = .06). However, 1.25 mg of albuterol (0.26 L/min; 95% CI -0.19, 0.72) and 2.5 mg (-0.10 L/min; 95% CI -0.77, 0.57) produced similar changes in EF75 when compared to saline. All secondary outcomes were similar between saline and 1.25 mg of albuterol. Peak inspiratory pressure needed to deliver goal tidal volumes (7.5% relative decrease, 95% CI 2.6, 12.3) and heart rate (6.5% increase, 95% CI 2.2, 10.8) differed significantly between albuterol 2.5 mg and saline., Conclusion: Albuterol at 1.25 mg and 2.5 mg, compared to aerosolized saline, did not affect EF75 in infants with sBPD receiving invasive ventilation. Greater improvement in peak inspiratory pressures with albuterol 2.5 mg suggests benefit, but close heart monitoring may be indicated., (© 2020 Wiley Periodicals LLC.)

Objectives: This study tested the hypothesis that longer duration of any type of respiratory support is associated with an increased rate of death or neurodevelopmental impairment (NDI) at 18-22 months., Methods: Retrospective cohort study using the Generic Database of NICHD Neonatal Research Network from 2006 to 2010. Infants were born at <27 weeks gestational age with birth weights of 401-1000 g. Respiratory support received during initial hospitalization from birth was characterized as follows: no support, only invasive support, only non-invasive support or mixed invasive, and non-invasive support. The primary outcome was death after 24 h of life or NDI at 18-22 months corrected age., Results: In a cohort of 3651 infants, 1494 (40.9%) died or had NDI. Cumulative respiratory support of any type beyond 60 days was associated with the likelihood of death or NDI. Infants who only received invasive support had the highest rate (89.1%), followed by those received mixed support (26.1%). Infants who received only non-invasive support had the lowest rate (7.7%). When compared to the only non-invasive support group, both invasive [OR 62.7 (95%CI 25.7, 152.6)] and mixed [OR 6.1 (95%CI 2.6, 14.4)] support groups were significantly more likely to die or have NDI., Conclusion: Prolonged respiratory support, whether invasive or non-invasive, is associated with increased odds of a poor outcome. The proportion of infants with a poor outcome increased in a dose dependent manner by two factors: the cumulative duration of respiratory support beyond 60 days, and the extent to which invasive support is provided., (© 2018 Wiley Periodicals, Inc.)

Introduction: High-flow nasal cannula therapy (HFNC) has been shown to be more effective than continuous positive airway pressure (CPAP) in reducing intubations and ventilator days. HFNC likely provides mechanisms to support respiratory efficiency beyond application of distending pressure. We reason that HFNC washout of nasopharyngeal dead space impacts CO(2) removal along with oxygenation. The aim of this study was to demonstrate the flow dependence of CO(2) reduction and improved oxygenation during HFNC and the dependence on leak around the nasal prongs., Materials and Methods: Neonatal piglets (n=13; 2-6 kg) were injured with IV oleic acid and supported with HFNC at 2 through 8 L/min. High and low leak around the nasal prongs was accomplished by using single and double prong cannulae, respectively. Measurement of hemodynamic, respiratory and blood gas parameters were made at each setting following 10 min for physiologic equilibration. Tracheal pressures were recorded by transmural catheters., Results: With HFNC, CO(2) trended downward in a flow-dependent manner independent of leak. Oxygenation and tracheal pressures increased in a flow-dependent manner with the greatest effect during double prong. At 8 L/min, tracheal pressures did not exceed 6 ± 1 cmH(2) O., Conclusions: HFNC improves gas exchange in a flow-dependent manner; double prong had greater impact on O(2;) single prong had greater impact on CO(2) elimination., (Copyright © 2010 Wiley-Liss, Inc.)

Unlabelled: Alterations in neonatal airway mechanics resulting from ventilatory therapies are implicated in airway collapse and chronic disease. Quantifying the functional impact of mechanical ventilation (MV) on the neonatal airway and elucidating the time course of these changes will support development of protective therapies. The objective of this study was to test the hypothesis that conventional MV would result in decreased static and dynamic elastance of an isolated tracheal segment and thinning of the muscle (trachealis) region of the tracheal wall in a time dependent manner. Tracheal segments were isolated in newborn lambs spontaneously breathing through the distal trachea; segments were MV (n = 7; PIP/PEEP = 35/5 cmH2O; 40 breaths/min) or instrumented, non-ventilated (SHAM; n = 7; PIP/PEEP = 0/0 cmH2O) for 4 hr. At baseline and hourly, tracheal segments were filled with saline, and static pressure-volume curves were constructed as the pressure response to stepwise volume infusions. Then, cross-sectional ultrasound images were captured at 0 cmH2O on SHAM, and at 0 cmH2O, peak inspiratory pressure (PIP) and positive end expiratory pressure (PEEP), on MV tracheae for subsequent dimensional analysis. Tracheal elasticity indices were derived from static pressure-volume data, and during dynamic ventilation using ultrasound images to calculate the stress-strain relationships. Over 4 hr of MV, tracheal internal diameter (ID) increased (14%; P < 0.05). Markers of tracheal mechanical properties indicated a decrease in elasticity under both static (bulk modulus; 28%; P < 0.05) and dynamic (elastic modulus; 282 %; P < 0.05) conditions, indicating a significant alteration in elastic components. No time dependent changes were identified in dimensions or mechanical properties in the SHAM group., Conclusions: MV results in dimensional alterations that increased anatomical dead space and reduced static and dynamic elastance of the neonatal trachea., ((c) 2006 Wiley-Liss, Inc.)