88 - Hyperinflation and its Association with Successful Transition to Home Ventilator Devices in Infants with Chronic Respiratory Failure and Severe Bronchopulmonary Dysplasia

Poster Board #: 88
Publication #: 1908-HP-QA.88

Background: Infants with chronic respiratory failure and severe bronchopulmonary dysplasia (sBPD) may require tracheostomy and long-term, mechanical ventilation. Transitioning from hospital devices to home, flow-triggered ventilators may be challenging when hyperinflation and limited diaphragm excursions are present.


Objective: To estimate the association between lung hyperinflation and the duration from time of tracheostomy to successful transition to home ventilators in infants with sBPD.


Design/Methods: We identified infants with sBPD < 32 weeks’ gestation receiving tracheostomy at our site. Hyperinflation by chest radiograph was the main exposure, defined as the presence of ≥ 10 ribs above the right side of the diaphragm at the time of tracheostomy. “Successful” transition to a home ventilator was attained after using this device with stable ventilator settings for 7 days. Time from tracheostomy to successful transition was the main outcome. Censoring was at 180 days post-tracheostomy. Kaplan-Meier and Cox proportional hazards were used to estimate the relationships between hyperinflation and time-to transition. Patient and clinical characteristics were considered confounding variables.


Results: Sixty-two infants were eligible for the analysis; 26 (42%) were hyperinflated. The median gestational age and birthweight were 25 weeks and 702.5g; 39% were female, 27% were small-for-gestational-age (SGA) < 10^th centile, and 56% had right ventricular (RV) dilation. Eleven died post-tracheostomy (8 had hyperinflation), and 51 successfully (18 were hyperinflated, p<0.05) transitioned. Hyperinflation was associated with mortality (31% vs 8.3%, p=0.02) and with an increased duration (72 vs. 56 days) to transition successfully (hazard ratio (HR) = 0.38, 95% CI: 0.19, 0.76, p=0.006, Figure 1). This association persisted in multivariable analysis after adjusting for the presence of RV dilation. Gestational age, birth weight, SGA, presence or severity of intra-ventricular hemorrhage, and sex were unrelated to the main outcome.

Conclusion(s): Hyperinflation is related to longer transition times from hospital to home ventilator devices for infants < 32 weeks’ gestation with chronic respiratory failure and sBPD. Strategies to reduce hyperinflation pre-tracheostomy may assist to decrease the duration of post-tracheostomy, inpatient care.


Kaplan-Meier Curve Comparing Liklihood of Remaining on Hospital Ventilator at Different Time Points Post-Tracheostomy in Hyperinflated vs. Non-hyperinflated Groups

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Authors/Institutions: Michael Reisfeld, Ann and Robert H Lurie Children's Hospital of Chicago, Chicago, Illinois, United States; Ryan J. Carpenter, McGaw Medical Center of Northwestern University, Chicago, Illinois, United States; Karna Murthy, McGaw Medical Center of Northwestern University, Chicago, Illinois, United States; Denise M. Goodman, McGaw Medical Center of Northwestern University, Chicago, Illinois, United States; Megan Lagoski, McGaw Medical Center of Northwestern University, Chicago, Illinois, United States