A 7-month-old boy is brought to the emergency department in mid-winter with a 3-day history of cough, rhinorrhoea, and increasing work of breathing. He is feeding less but still has wet nappies. Temperature is 37.9 °C, respiratory rate 52 breaths/min, oxygen saturation 93 percent on room air. There are diffuse crackles and wheeze with mild subcostal indrawing. Which management strategy is most appropriate according to Canadian paediatric bronchiolitis guidance?