Asthma as a comorbidity in COVID-19 pediatric ICU admissions in a large metropolitan children's hospital.

RATIONALE: Children contribute to 5% of coronavirus disease of 2019 (COVID-19)-related hospitalizations in the United States. There is mounting evidence suggesting childhood asthma is a risk factor for severe disease. We hypothesized that asthma is associated with longer length of stay (LOS) and need for respiratory support among children admitted to pediatric intensive care unit (PICU) with COVID-19. METHODS: We reviewed 150 charts of children and young adults with a positive severe acute respiratory syndrome coronavirus 2polymerase chain reaction test admitted to the PICU at Children's National Hospital, Washington, DC between 2020 and 2021. We recorded demographics, anthropometrics, past medical history, clinical course, laboratory findings, imaging, medication usage, respiratory support, and outcomes. Functional Status Scale (FSS), which measures an Intensive Care Unitpatient's physical function, was used to characterize children with multiple comorbidities; FSS and obesity were included as covariates in multivariate analysis. Statistical analysis was performed using SPSS v25.0. RESULTS: Sixty-Eight patients ages 0-21 years met inclusion criteria. Median age was 14.9 years, 55.9% were female, median Body Mass Index percentile was 62, and 42.6% were African American. Compared with those without asthma, patients with asthma averaged longer LOS (20.7 vs. 10.2 days, p = 0.02), with longer PICU stay (15.9 vs. 7.6 days, p = 0.033) and prolonged maximum respiratory support (8.3 vs. 3.3 days, p = 0.016). Adjusted for obesity and poor physical function (FSS > 6), asthma remained a significant predictor of hospital LOS, PICU LOS, and days on maximum respiratory support. CONCLUSION: Asthma can cause severe disease with prolonged need for maximum respiratory support among children with COVID-19.

Frequent hypoxemia found in infants with bronchopulmonary dysplasia after weaning home oxygen.

OBJECTIVE: Parental reports and brief clinical examinations are the primary information used to assist clinicians in weaning home supplemental oxygen in infants with bronchopulmonary dysplasia (BPD). Recorded nocturnal oximetry provides an objective assessment of hypoxemia; however, it is unknown if it identifies clinically undetected hypoxemia in the home setting. Our objective was to determine if nocturnal oximetry can identify unreported hypoxemia in infants with BPD who appear ready to wean from supplemental oxygen. STUDY DESIGN: We conducted a retrospective chart review of infants born <32 weeks gestation with BPD who were discharged to home receiving supplemental oxygen and completed recorded nocturnal oximetry in room air during an 18-month period. Abnormal oximetry was defined as >5 min with SpO2 < 90% and/or an oxyhemoglobin desaturation index (ODI4) >5. Comparative analysis of patients with normal and abnormal overnight oximetry was performed using Fisher Exact and Wilcoxon signed-rank test. RESULTS: Thirty-five former premature infants completed nocturnal oximetry at 5.8 (3.4-8.3) months corrected age. Nocturnal oximetry was abnormal as defined in 67% of the cohort (n = 21). Five percent of patients were hypoxemic, 52% had frequent desaturation events, and 43% had both. No significant differences existed in neonatal characteristics between patients with normal and abnormal studies. CONCLUSIONS: Nocturnal oximetry was abnormal in the majority of infants with BPD who were otherwise clinically ready to wean from oxygen support, suggesting that recorded home oximetry could be a feasible and useful tool to evaluate for otherwise clinically unapparent nocturnal hypoxemia in patients with BPD.

A pediatric hospital-wide asthma severity score: Reliability and effectiveness.

BACKGROUND: Asthma is a leading cause of pediatric hospitalization in the United States. Children hospitalized with asthma are often managed in different care settings during hospitalization, posing challenges to accurate communication among care providers about illness severity. Our objective was to study the feasibility, reliability, and safety of a new pediatric hospital-wide asthma severity score (HASS) across different care units within a single tertiary-care pediatric center. METHODS: 150 patients between the ages of 2 and 18 years hospitalized with a principal diagnosis of status asthmaticus were included in this study. Study patients were followed from the time of initial triage in the emergency department until the time of medical readiness for discharge. Rates of medical errors, early transfers to a higher level of care and medically indicated hospital length of stay (LOS) were compared between 75 patients before and 75 patients after widespread implementation of the HASS using retrospective chart review and anonymous staff reporting. Interrater reliability was determined by collecting independent HASS scores from blinded staff members after tandem or simultaneous patient assessment. RESULTS: Interrater reliability among untrained staff members using the HASS was high. Hospital LOS, rates of adverse events, medical errors, and early transfer to a higher level of care were not significantly different before and after widespread HASS implementation. CONCLUSION: The HASS is a reliable asthma severity tool that can be used throughout hospitalization and among multiple clinical providers to trend clinical progress and optimize communication, particularly during times of care handoffs.

Is implementation of a hospital pathway for high-flow nasal cannula initiation and weaning associated with reduced high-flow duration in bronchiolitis?

BACKGROUND: High-flow nasal cannula (HFNC) therapy is widely used for children with bronchiolitis, but its optimal role remains uncertain. Our institution created and later revised a clinical pathway guiding HFNC initiation and weaning. METHODS: A retrospective review of 1690 bronchiolitis encounters was conducted. Trends in the duration of HFNC and hours spent weaning HFNC as proportions of the monthly hospital length of stay (LOS) for bronchiolitis, hospital LOS, and escalation of care were compared using interrupted time series (ITS) models across three study periods: Baseline (HFNC managed at provider discretion), Intervention 1 (pathway with initiation at 0.5 L/kg/min and escalation up to 2 L/kg/min), and Intervention 2 (revised pathway, initiation at the maximum rate of 2 L/kg/min). Both pathway iterations provided titration and weaning guidance. Maximum respiratory scores were used to adjust for case severity. RESULTS: After adjustment for severity and time, both HFNC duration and HFNC weaning time (as a proportion of monthly LOS) decreased at the start of Intervention 1, but subsequently increased. During Intervention 2, both these measures trended downward, returning to baseline. Total LOS did not change in the baseline or intervention periods. Escalation of care did not differ from baseline to the end of Intervention 2. CONCLUSION: Initiating HFNC at higher flow rates with weaning guidance for children hospitalized with bronchiolitis was associated with a reduction in HFNC duration without differences in LOS or escalation of care. These findings suggest that standardization through clinical pathways can limit HFNC duration in bronchiolitis.

High flow nasal cannula versus standard low flow nasal oxygen during flexible bronchoscopy in children: A randomized controlled trial.

BACKGROUND: Hypoxemia is the most frequent complication of fiberoptic bronchoscopy (FB) in children. Guidelines recommend oxygen supplementation and conventional nasal prongs (NC) are used for this purpose. The aim of this study was to evaluate if the use of high-flow nasal cannula therapy (HFNC) in children undergoing FB result in a lower incidence of hypoxemia than standard oxygen administration. METHODS: Patients aged 1 month-16 years undergoing elective FB were included in a prospective randomized controlled, nonblinded, single-center clinical trial and randomly assigned to receive oxygen via NC or HFNC. Patients' baseline characteristics were recorded pre-bronchoscopy. The primary outcome was oxygen desaturation during the procedure defined as saturation less than 94%. RESULTS: An intention to treat analysis for 53 patients receiving NC and 51 receiving HFNC, showed HFNC patients were less likely to have hypoxemia than were NC patients (p = .011), with an absolute risk reduction of 0.27 (95% confidence interval [CI]: 0.08-0.45) and a number needed to treat of 3.75 (95% CI: 2.22-12.04). Moderate hypoxemia (SpO2 ≥ 90% and <94%, and <60 s) was observed significantly less often with HFNC than with NC (p = .012). Severe hypoxemia (SpO2 < 90% and >30 s) was not different between groups. Patients undergoing bronchoalveolar lavage (BAL) presented fewer desaturations with HFNC (p = .0003). CONCLUSIONS: HFNC offers optimized oxygenation during elective FB with a significant reduction in desaturations and can be considered for oxygen administration, especially when BAL is performed.

Bronchopulmonary dysplasia-A historical perspective.

Bronchopulmonary dysplasia (BPD) was first described by Northway et al in 1967. This article describes the evolution of our understanding of the pathophysiology of BPD and the approaches to treatments of this illness developed over the past fifty years. These interventions had their roots in the understanding of the principles of the surface tension present at air-liquid interfaces, which were developed over 150 years before BPD's initial description. Improving outcomes in neonatal care have led to greater survival of preterm and very preterm infants, and to an evolution of the pathogenesis and pathology of BPD, from an illness caused primarily by barotrauma and oxygen toxicity to one of interruption of lung development. While the incidence of BPD has remained about the same in recent decades, this is because survival of infants born at lower gestational ages is increasing. Understanding of molecular, genetic and physiologic mechanisms has led to newer treatments that have mitigated some of the harmful effects of prolonged mechanical ventilation. Recognition of BPD as a chronic multi-system disease has resulted in further improvements in care after discharge from neonatal intensive care. Since many of the origins of chronic obstructive lung disease in adults are based in childhood respiratory illnesses, improving outcomes of BPD in infancy and childhood will undoubtedly lead to improved respiratory outcomes in the adults that these children will become.

Prematurity, the diagnosis of bronchopulmonary dysplasia, and maturation of ventilatory control.

Infants born before 32 weeks gestational age and receiving respiratory support at 36 weeks postmenstrual age (PMA) are diagnosed with bronchopulmonary dysplasia (BPD). This label suggests that their need for supplemental oxygen (O2 ) is primarily due to acquired dysplasia of airways and airspaces, and that the supplemental O2 is treating residual parenchymal lung disease. However, emerging evidence suggests that immature ventilatory control may also contribute to the need for supplemental O2 at 36 weeks PMA. In all newborns, maturation of ventilatory control continues ex utero and is a plastic process. Among premature infants, supplemental O2 mitigates the hypoxemic effects of delayed maturation of ventilatory control, as well as reduces the duration and frequency of periodic breathing events. Nevertheless, prematurity is associated with altered and occasionally aberrant maturation of ventilatory control. Infants born prematurely, with or without a diagnosis of BPD, are more prone to long-lasting effects of dysfunctional ventilatory control. This review addresses normal and abnormal maturation of ventilatory control and suggests how aberrant maturation complicates assigning the diagnosis of BPD. Greater awareness of the interaction between parenchymal lung disease and delayed maturation of ventilatory control is essential to understanding why a given premature infant requires and is benefitting from supplemental O2 at 36 weeks PMA.

Efficacy of noninvasive respiratory support modes as postextubation respiratory support in preterm neonates: A systematic review and network meta-analysis.

BACKGROUND: Multiple noninvasive respiratory support (NRS) modalities are used for postextubation support in preterm neonates. Seven NRS modalities were compared-constant flow continuous positive airway pressure (CPAP) (CF-CPAP) (bubble CPAP; ventilator CPAP), variable flow CPAP (VF-CPAP), high flow nasal cannula (HFNC), synchronized noninvasive positive pressure ventilation (S-NIPPV), nonsynchronized NIPPV (NS-NIPPV), bilevel CPAP (BiPAP), noninvasive high-frequency oscillation ventilation (nHFOV). DESIGN: Systematic review and network meta-analysis (NMA) using the Bayesian random-effects approach. MEDLINE, EMBASE, CENTRAL, WHO-ICTRP were searched. MAIN OUTCOME MEASURE: Requirement of invasive mechanical ventilation within 7 days of extubation. RESULTS: A total of 33 studies with 4080 preterm neonates were included. S-NIPPV, NS-NIPPV, nHFOV, and VF-CPAP were more efficacious in preventing reintubation than CF-CPAP (risk ratio [RR] [95% credible intervals {CrI}]: 0.22 [0.12, 0.35]; 0.44 [0.27, 0.67]; 0.42 [0.18, 0.81]; 0.73 [0.52, 0.99]). Surface under the cumulative ranking curve (SUCRA) value ranked S-NIPPV to be the best postextubation intervention (SUCRA: 0.98). S-NIPPV was more effective than NS-NIPPV, BiPAP, VF-CPAP, and HFNC (RR [95% CrI]: 0.52 [0.24, 0.97]; 0.32 [0.14, 0.64]; 0.30 [0.16, 0.50]; 0.24 [0.12, 0.41]). NS-NIPPV resulted in lesser reintubation compared to VF-CPAP and HFNC (RR [95% CrI]: 0.61 [0.36, 0.97]; 0.49 [0.27, 0.80]). BiPAP, VF-CPAP, and HFNC had comparable efficacies. The overall quality of evidence was very low to moderate. CONCLUSION: Results of this NMA indicate that S-NIPPV might be the most effective and CF-CPAP the least effective NRS modality for preventing extubation failure.

A Case of "Abnormally Abnormal" Hypoxic Ventilatory Responses: A Novel NPARM PHOX 2B Gene Mutation.

ABSTRACT: Congenital central hypoventilation syndrome (CCHS) is a rare disorder associated with dysregulation of the autonomic ventilatory response to hypoxia and hypercarbia usually caused by polyalanine repeat expansion mutations in the PHOX 2B gene. Non-polyalanine repeat mutations (NPARM) represent approximately 10% of cases, and usually require continuous ventilation during sleep, although our knowledge of disease progression is limited. Here we present a case with a novel NPARM CCHS mutation associated with a premature stop codon for the PHOX 2B protein. Despite the type of the mutation, patient management with supplementary oxygen has been sufficient. Experience from our case may help when counseling parents.