Acute severe asthma Respiratory Status asthmaticus
Conditions
Interventions
This is a feasibility randomised controlled trial (RCT) of early HiFlo versus standard care, in children aged 2 to 11 years with ASA which has not responded to first-line therapy in the emergency depa
Sponsors
Brighton and Sussex University Hospitals NHS Trust
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Age 2-11 years 2. Acute severe asthma ASA, defined as respiratory distress combined with wheeze on auscultation (a formal preceding diagnosis of asthma is not necessary) 3. Failure to respond to standard initial emergency management with 'burst' therapy (back-to-back 3 consecutive inhaled or nebulised doses of salbutamol with or without the addition of ipratropium bromide over a 1-hour period) plus systemic corticosteroids, with or without subsequent intravenous bronchodilator therapy as deemed appropriate by the treating physician. Failure to respond will be defined as PRAM score of 5 or more, between 1 and 4 hours after starting burst therapy. PRAM score has been shown to be a good predictor of need for admission and escalation of therapy. A child with PRAM score = 5 would typically have moderately increased work of breathing, audible wheeze and oxygen saturation below 92% but above 90%.
Exclusion criteria
Exclusion criteria: 1. Clinical/radiological evidence of bacterial pneumonia: fever > 38.5°C PLUS focal signs on auscultation or chest X-ray 2. Signs of impending respiratory failure mandating imminent intubation. These will be at the discretion of the treating clinical team, but would include elevated pCO2, refractory hypoxaemia and exhaustion 3. Contraindications to use of HiFlo: 3.1. Air leak (pneumothorax, pneumomediastinum or subcutaneous emphysema) 3.2. Decreased level of consciousness - AVPU score P or worse 3.3. Recent (within 6 weeks) bowel surgery 3.4. Intractable vomiting 4. Other major respiratory, cardiovascular or neurological condition. 5. Previous participation in the HiFlo ASA study, during a prior hospital episode
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Primary feasibility outcome measures: 1. Proportion of recruited children amongst eligible patients with ASA, measured using counts from screening and eligibility forms and logs at enrolment 2. Proportion of children with signed deferred consent amongst those recruited into the study, measured using counts from consent tracking forms and logs at deferred consent 3. Proportion of data collection complete per participant, measured using counts from validated MACRO database after discharge 4. Summary statistics for candidate primary outcomes, measured using counts from validated MACRO database after discharge 5. Proposed design, sample size and number of centres for a definitive study, evaluated from final study report at end of study 6. Satisfaction measured using end of study questionnaire (Likert or visual analogue scale for parents/pictographic tools for children) at discharge Two candidate primary outcome measures are to be recorded and evaluated as part of feasibility objectives 3 and 4: 1. Treatment failure needing escalation of therapy is measured by monitoring PRAM score, respiratory rate, heart rate, FiO2 and pCO2 at the following timepoints: randomisation (T0), hourly during the first four hours after randomisation (T1-T4) and four-hourly afterwards until discharge from hospital (T8, T12, T16, ...) 2. Time between presentation to the Emergency Department and meeting hospital discharge criteria is measured in hours using hospital records at hospital discharge. Actual hospital discharge criteria measured by monitoring SpO2, FiO2, respiratory support and frequency of inhaled bronchodilators from the time a patient is stable/improving at the timepoints mentioned above | — |
Secondary
| Measure | Time frame |
|---|---|
| The following candidate secondary outcome measures are to be evaluated: 1. Time (hours) between presentation to ED and actual hospital discharge, measured from data in hospital records at discharge 2. Time (hours) between presentation to ED and achieving a Paediatric Respiratory Assessment Measure (PRAM) score = 3, measured from data in validated MACRO database from PRAM measurements at the established study timepoints: randomisation (T0), hourly during the first four hours after randomisation (T1-T4) and four-hourly afterwards until discharge from hospital (T8, T12, T16, ...) 3. Time (hours) between presentation to ED and ability to maintain SaO2 = 92% without supplemental oxygen or respiratory support, measured from data in validated MACRO database from oxygen-related measurements at the established study timepoints as stated above 4. Need for intravenous (IV) bronchodilator therapy, measured using counts from validated MACRO database from therapy records at the established study timepoints as stated above 5. Duration of IV bronchodilator therapy, measured from data in validated MACRO database from therapy records at the established study timepoints as stated above 6. Requirement for non-invasive ventilation, measured using counts from validated MACRO database from therapy records at the established study timepoints as stated above 7. Requirement for invasive ventilation (intubation), measured using counts from validated MACRO database from therapy records at the established study timepoints as stated above 8. Treatment-related adverse effects, measured using counts from validated MACRO database from safety reporting records at the established study timepoints as stated above 9. Hospital readmission within 48 hours of discharge, measured using counts from hospital records and patient research logs at 48 hours after discharge 10. Acceptability and comfort score for treatment during the episode, recorded by end of study questionnaire (Likert or visual analogue scale | — |
Countries
England, United Kingdom
Outcome results
None listed