Rationale: Despite lower overall hospitalization rates for asthma in recent years, there has been an increase in the number of pediatric patients receiving intensive care management in the United States. Objectives: To investigate how the use of invasive and noninvasive mechanical ventilation for asthma has changed in the context of an evolving cohort of critically ill pediatric patients with asthma. Methods: We analyzed children admitted to intensive care units for asthma from 2009 through 2019 in the Virtual Pediatric Systems database. Regression analyses were used to evaluate how respiratory support interventions, mortality, and patient characteristics have changed over time. Odds ratios were calculated to determine how patient characteristics were associated with respiratory support needs. Stratified analyses were performed to determine how changing practice patterns may have differed between patient subgroups. Results: There were 67,614 admissions for 56,727 patients analyzed. Intubation occurred in 4.6% of admissions and decreased from 6.9% to 3.4% over time (P < 0.001), whereas noninvasive ventilation as the maximal respiratory support increased from 8.9% to 20.0% (P < 0.001). Over time, the cohort shifted to include more 2- to 6-year-olds and patients of Asian/Pacific Islander or Hispanic race/ethnicity. Although intubation decreased and noninvasive ventilation increased in all subgroups, the changes were most pronounced in the youngest patients and slightly less pronounced for obese patients. Conclusions: In pediatric asthma, use of intubation has halved, whereas use of noninvasive ventilation has more than doubled. This change in practice appears partially related to a younger patient cohort, although other factors merit exploration.

Objectives: Data on outcomes of children with cystic fibrosis admitted to PICUs are limited and outdated. Prior studies cite PICU mortality rates ranging from 37.5% to 100%. Given the advances made in cystic fibrosis care, we expect outcomes for these patients to have changed significantly since last studied. We provide an updated report on PICU mortality and the factors associated with death among critically ill children with cystic fibrosis. Design: Retrospective multicenter cohort analysis utilizing data from the Virtual Pediatric Systems database. Setting: Data were collected from 135 PICUs from January 1, 2009, to June 20, 2018. Patients: One-thousand six-hundred thirty-three children with cystic fibrosis accounting for 2,893 PICU admissions were studied. Interventions: None. Measurements and Main Results: The primary outcome was mortality during PICU admission. Predictors included demographics, anthropometrics, diagnoses, clinical characteristics, and critical care interventions. Odds ratios of mortality were calculated in univariate and multivariable analyses to assess differences in mortality associated with predictor variables. Generalized estimating equation models were used to account for multiple admissions per patient. The overall PICU mortality rate was 6.6%. Factors associated with increased odds of mortality included hemoptysis/pulmonary hemorrhage, pneumothorax, gastrointestinal bleeding, bacterial/fungal infections, lower body mass index/malnutrition, and need for noninvasive or invasive respiratory support. Intubation/mechanical ventilation occurred in 26.4% of the 2,893 admissions and was associated with a 19.1% mortality rate. Of the nonsurvivors, 20.7% died without receiving mechanical ventilation. Conclusions: The mortality rate during PICU admissions for patients with cystic fibrosis is lower than has been reported in prior studies, both in the overall cohort and in the subset requiring invasive mechanical ventilation. These data provide updated insight into the prognosis for cystic fibrosis patients requiring critical care.

Diffuse alveolar hemorrhage (DAH) is a life-threatening pulmonary toxicity that can arise after hematopoietic cell transplantation (HCT). Risk factors and outcomes are not well understood owing to a sparsity of cases spread across multiple centers. The objectives of this epidemiologic study were to characterize the incidence, outcomes, transplantation-related risk factors and comorbid critical care diagnoses associated with post-HCT DAH. Retrospective analysis was performed in a multicenter cohort of 6995 patients age ≤21 years who underwent allogeneic HCT between 2008 and 2014 identified through the Center for International Blood and Marrow Transplant Research registry and cross-matched with the Virtual Pediatric Systems database to obtain critical care characteristics. A multivariable Cox proportional hazard model was used to determine risk factors for DAH. Logistic regression models were used to determine critical care diagnoses associated with DAH. Survival outcomes were analyzed using both a landmark approach and Cox regression, with DAH as a time-varying covariate. DAH occurred in 81 patients at a median of 54 days post-HCT (interquartile range, 23 to 160 days), with a 1-year post-transplantation cumulative incidence probability of 1.0% (95% confidence interval [CI], .81% to 1.3%) and was noted in 7.6% of all pediatric intensive care unit patients. Risk factors included receipt of transplantation for nonmalignant hematologic disease (reference: malignant hematologic disease; hazard ratio [HR], 1.98; 95% CI, 1.22 to 3.22; P = .006), use of a calcineurin inhibitor (CNI) plus mycophenolate mofetil (MMF) as graft-versus-host disease (GVHD) prophylaxis (referent: CNI plus methotrexate; HR, 1.89; 95% CI, 1.07 to 3.34; P = .029), and grade III-IV acute GVHD (HR, 2.67; 95% CI, 1.53-4.66; P < .001). Critical care admitted patients with DAH had significantly higher rates of systemic hypertension, pulmonary hypertension, pericardial disease, renal failure, and bacterial/viral/fungal infections (P < .05) than those without DAH. From the time of DAH, median survival was 2.2 months, and 1-year overall survival was 26% (95% CI, 17% to 36%). Among all HCT recipients, the development of DAH when considered was associated with a 7-fold increase in unadjusted all-cause post-HCT mortality (HR, 6.96; 95% CI, 5.42 to 8.94; P < .001). In a landmark analysis of patients alive at 2 months post-HCT, patients who developed DAH had a 1-year overall survival of 33% (95% CI, 18% to 49%), compared to 82% (95% CI, 81% to 83%) for patients without DAH (P < .001). Although DAH is rare, it is associated with high mortality in the post-HCT setting. Our data suggest that clinicians should have a heightened index of suspicion of DAH in patients with pulmonary symptoms in the context of nonmalignant hematologic indication for HCT, use of CNI + MMF as GVHD prophylaxis, and severe acute GVHD. Further investigations and validation of modifiable risk factors are warranted given poor outcomes.

Objective: To determine the incidence, risk factors, and outcomes of pulmonary hypertension (PH) in the pediatric intensive care unit (PICU) after pediatric hematopoietic stem cell transplant (HCT).Methods: This was a retrospective study of pediatric patients who underwent allogeneic HCT between January 2008-December 2014 at a center contributing to the Center for International Blood and Marrow Transplant Research data registry. Incidence of PH was assessed from PICU diagnostic codes from records merged from the Virtual Pediatric Systems database. Regression and survival analyses identified factors associated with post-HCT PH. Additional post-HCT morbidities and survival after PH were also assessed.Results: Among 6,995 HCT recipients, there were 29 cases of PH, a cumulative incidence of 0.42% (95% CI 0.27%-0.57%) at 60 months post-HCT. In the sub-cohort of 1,067 patients requiring intensive care after HCT, this accounted for a PH prevalence of 2.72% (95% CI 1.74–3.69%). There was an increased risk of developing PH associated with Black/African American race, metabolic disorders, partially HLA-matched or cord blood allografts, graft-versus-host prophylaxis regimen, and lower pre-HCT functional status. Patients who developed PH had significant PICU comorbidities including heart failure, pulmonary hemorrhage, respiratory failure, renal failure, and infections. Survival at 6 months after diagnosis of post-HCT PH was 51.7% (95% CI 32.5%-67.9%).Conclusions: PH is a rare but serious complication in the pediatric post-HCT population. A significant burden of additional comorbidities, procedural interventions, and risk of mortality is associated with its development. Close monitoring and prompt intervention for this severe complication are necessary in this vulnerable population.

We present novel insight into the circulating microRNA profiles of pediatric patients with pulmonary hypertension. Our findings support the utility of microRNAs as both useful biomarkers of disease severity and potential therapeutic targets in pediatric pulmonary hypertension.