Non-invasive Ventilation vs. Standard Therapy for Children Hospitalized With an Acute Exacerbation of Asthma
Non-invasive Ventilation vs. Standard Therapy for Children Hospitalized With an Acute Exacerbation of Asthma
Acute asthma produces greatly increased work of breathing and increased oxygen requirement
 secondary to bronchial narrowing and airway obstruction by inflammatory secretions. There is
 growing evidence that non-invasive ventilation can reverse these processes more efficiently
 than conventional asthma therapy. Surprisingly, there have not yet been any large scale
 prospective controlled studies to investigate this hypothesis, (either in adults or
 children). Consequently, the aim of this study is to determine if the use of non-invasive
 positive airway pressure, for children admitted to hospital with an acute exacerbation of
 asthma, reduces their work of breathing, need for adjunctive medications, and shortens the
 length of hospital stay, compared to current standard therapy.
The aim of the study is to determine if the use of NIV, for children admitted to hospital
 with an acute exacerbation of asthma, reduces their work of breathing, need for adjunctive
 medication, length of hospital stay, and need for intubation and mechanical ventilation.
 Study design will be prospective, randomized and controlled. The tightly fitting face mask
 necessary for NIV makes it impossible to make this a blinded study.

 The principal enrollment criteria will be children over 2 years of age presenting to the ER
 with acute asthma. After diagnosis, all children are treated with standard therapy (systemic
 steroids plus 3 doses of inhaled salbutamol and 1 dose of inhaled ipratropium over a 1 hour
 period then hourly salbutamol). The principal decision between discharge track and admission
 track will be made at 2 hours after first steroid dose. Admission criteria are based on
 sequential PRAM scores.

 After initial asthma treatment and observation in the emergency room, to determine which
 patients can be discharged home, those who need admission will be asked to join the study,
 then consented and randomized. There will be three treatment groups:

 -  BiPAP: standard steroid dose, hourly salbutamol and BiPAP at 15/5 cm H2O by face mask
 with rate 10 to 15/min, oxygen as needed.

 -  CPAP: standard steroid dose, hourly salbutamol and 8 to 10 cm H2O constant pressure by
 face mask, oxygen as needed.

 -  Conventional therapy: standard steroid dose plus hourly nebulized salbutamol, nebulized
 ipratropium q 6 hrly, magnesium sulphate 50 mg/kg IV (4 doses q 6 hrly), loading dose of
 aminophylline 6 mg/kg IV if no progress, oxygen as needed.

 All children will be admitted to a small 3 bed respiratory unit. They will be closely
 monitored and objectively scored every 4 hours using the PRAM asthma clinical severity score
 (Pediatric Respiratory Assessment Measure). Projected patient enrollment will be at least 30
 in each arm. Estimated study duration is 6 months.
Inclusion Criteria:

 -  2-18 years old

 -  Clinical diagnosis of acute asthma exacerbation (respiratory rate greater than WHO's
 age-dependent criteria, a history of similar previous episodes and wheezing heard on
 auscultation by an experienced physician)

 -  PRAM score of 8 or more after 2 hours post-steroid administration

 -  Parents willing and able to sign consent

 -  Children over the age of 6 willing to provide assent

 Exclusion Criteria:

 -  Clinical suspicion of bacterial pneumonia: focal crackles or bronchial breathing,
 and/or major chest x-ray findings.

 -  Impending respiratory failure at presentation requiring direct PICU admission

 -  Any contraindication to BiPAP use including altered mental status, recent bowel
 surgery, intractable vomiting, inability to protect airway, pneumothorax.

 -  Receiving maintenance dose of oral steroid at time of hospital admission

 -  History of serious unrelated illness such as congenital heart disease or
 bronchopulmonary dysplasia.