RESUMO
BACKGROUND: Acute severe asthma (ASA) is a leading cause of hospital attendance in children. Standard first-line therapy consists of high-dose inhaled bronchodilators plus oral corticosteroids. Treatment for children who fail to respond to first-line therapy is problematic: the use of intravenous agents is inconsistent, and side effects are frequent. High-flow humidified oxygen (HiFlo) is widely used in respiratory conditions and is increasingly being used in ASA, but with little evidence for its effectiveness. A well-designed, adequately powered randomized controlled trial (RCT) of HiFlo therapy in ASA is urgently needed, and feasibility data are required to plan such an RCT. In this study, we describe the protocol for a feasibility study designed to fill this knowledge gap. OBJECTIVE: This study aims to establish whether a full RCT of early HiFlo therapy in children with ASA can be conducted successfully and safely, to establish whether recruitment using deferred consent is practicable, and to define appropriate outcome measures and sample sizes for a definitive RCT. The underlying hypothesis is that early HiFlo therapy in ASA will reduce the need for more invasive treatments, allow faster recovery and discharge from hospital, and in both these ways reduce distress to children and their families. METHODS: We conducted a feasibility RCT with deferred consent to assess the use of early HiFlo therapy in children aged 2 to 11 years with acute severe wheeze not responding to burst therapy (ie, high-dose inhaled salbutamol with or without ipratropium). Children with a Preschool Respiratory Assessment Measure score ≥5 after burst therapy were randomized to commence HiFlo therapy or follow standard care. The candidate primary outcomes assessed were treatment failure requiring escalation and time to meet hospital discharge criteria. Patient and parent experiences were also assessed using questionnaires and telephone interviews. RESULTS: The trial was opened to recruitment in February 2020 but was paused for 15 months owing to the COVID-19 pandemic. The trial was reopened at the lead site in July 2021 and opened at the other 3 sites from August to December 2022. Recruitment was completed in June 2023. CONCLUSIONS: This feasibility RCT of early HiFlo therapy in children with ASA recruited to the target despite major disturbances owing to the COVID-19 pandemic. The data are currently being analyzed and will be published separately. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number Registry ISRCTN78297040; https://www.isrctn.com/ISRCTN78297040. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/54081.
RESUMO
OBJECTIVES: (1) To examine whether infants with severe bronchiolitis, fulfilling criteria for further respiratory support, could be managed outside a Pediatric Intensive Care Unit (PICU) with non-invasive ventilation (NIV) alone. (2) To study the characteristics, clinical course and outcome of NIV responders and non responders to assess safety and efficacy and inform guideline construction. HYPOTHESIS: Infants with severe bronchiolitis can be safely managed with NIV outside a PICU. STUDY DESIGN: Retrospective case review. PATIENT SELECTION: Cohort of infants with objective evidence of severe bronchiolitis requiring respiratory support nursed in a Pediatric High Dependency Unit (PHDU) and/or Intensive Care Unit (ICU) between 2001 and 2007. METHODOLOGY: Analysis of patient characteristics and respiratory parameters at admission and initiation of ventilation, changes after 2 and 4 hr of NIV or invasive ventilation, complications, short and long-term outcomes were analyzed. RESULTS: One thousand and thirty-five infants with bronchiolitis were admitted with 67 ventilation episodes identified from 65 patients. Fifty-five episodes, including 34 with apnea, were treated exclusively with NIV. Six infants failed to respond and were invasively ventilated. Six patients were invasively ventilated at presentation. Non-responders had a significantly higher rate of bacterial infection. Significant improvements in respiratory parameters in responders occurred by 2 hr and sustained at 4 hr. Duration of hospital stay, ventilation requirement and oxygen requirement were significantly shorter in responders. Short and longer-term follow up data did not identify any adverse effects related to NIV. CONCLUSIONS: NIV was effective in 80% of infants receiving respiratory support for severe bronchiolitis.
