Patent Ductus Arteriosus and Lung Magnetic Resonance Imaging Phenotype in Moderate and Severe Bronchopulmonary Dysplasia-Pulmonary Hypertension.

Rationale: Hemodynamically significant patent ductus arteriosus (hsPDA) in premature infants has been associated with bronchopulmonary dysplasia (BPD) and pulmonary hypertension (PH). However, these associations remain incompletely understood. Objectives: To assess the associations between hsPDA duration and clinical outcomes, PH, and phenotypic differences on lung magnetic resonance imaging (MRI). Methods: In this retrospective cohort study, we identified all infants with BPD at <32 weeks' gestation who also underwent research lung MRI at <48 weeks' postmenstrual age (PMA) from 2014 to 2022. Clinical echocardiograms were reviewed for hsPDA and categorized as no hsPDA, hsPDA 1-60 days, and hsPDA >60 days. Outcome variables included BPD severity, PH at 36 weeks' PMA, PH after 36 weeks' PMA in the absence of shunt (PH-pulmonary vascular disease [PVD]), tracheostomy or death, and lung phenotype by MRI via modified Ochiai score, indexed total lung volume, and whole-lung hyperdensity. Logistic regression and ANOVA were used. Measurements and Main Results: In total, 133 infants born at 26.2 ± 1.9 weeks, weighing 776 ± 276 g, were reviewed (47 with no hsPDA, 44 with hsPDA 1-60 days, and 42 with hsPDA >60 d). hsPDA duration > 60 days was associated with BPD severity (P < 0.01), PH at 36 weeks' PMA (adjusted odds ratio [aOR], 9.7 [95% confidence interval (CI), 3.3-28.4]), PH-PVD (aOR, 6.5 [95% CI, 2.3-18.3]), and tracheostomy or death (aOR, 3.0 [95% CI, 1.0-8.8]). Duration of hsPDA > 60 days was associated with higher Ochiai score (P = 0.03) and indexed total lung volume (P = 0.01) but not whole-lung hyperdensity (P = 0.91). Conclusions: In infants with moderate or severe BPD, prolonged exposure to hsPDA is associated with BPD severity, PH-PVD, and increased parenchymal lung disease by MRI.

Patient factors associated with positive respiratory cultures following tracheostomy in pediatric patients.

OBJECTIVES: An increasing number of pediatric patients undergo tracheostomy placement annually. Despite advances in care, these patients remain at high risk for postoperative complications, including respiratory infections. The risk factors for positive respiratory cultures and the impact of culture positivity on overall morbidity and mortality in this population is not fully characterized. STUDY DESIGN AND SETTING: Retrospective cross-sectional analysis of all patients within a single tertiary care institution who underwent tracheostomy placement from January 1, 2019 to 12/31/2021. METHODS: We collected patient demographic information, comorbidities, primary indication for tracheostomy placement, and respiratory culture information preoperatively and postoperatively. The primary outcome measure was positive bacterial respiratory culture with speciation within 1, 3, or 6 months of tracheostomy placement. The secondary outcome measure was all-cause mortality within the study period. RESULTS: A total of 180 patients with median (IQR) age of 5.2 (3.4-31.0) months at time of tracheostomy placement were included in the study. Nearly half of patients had a positive culture within 1 month (n = 81,47.4 %) while 63.7 % of patients were positive within 6 months of tracheostomy placement (n = 109). Risk factors included respiratory and/or cardiac comorbidities. Positive respiratory cultures within 6 months of surgery and cardiac and/or neurologic comorbidities were associated with increased all-cause mortality following tracheostomy placement. CONCLUSIONS: Positive respiratory cultures are common following tracheostomy placement, more so in patients with cardiac and pulmonary comorbid conditions. Positive cultures are associated with increased all-cause mortality. More work is necessary to determine optimal screening frequency and treatment protocols for positive cultures in this population.