The investigators hypothesize that the use of BiPAP in children with moderate to severe asthma exacerbations could reduce the length of hospital stay, need for invasive ventilation, and use of intravenous bronchodilators. The investigators aim to test this hypothesis by randomizing children attending the Emergency Department with a moderate to severe clinical severity score refractory to inhaled bronchodilators to receive either BiPAP in addition to standard asthma care, or standard care alone.