A 4-month-old previously well infant presents with a 2-day history of cough, rhinorrhoea, poor feeding and increased work of breathing. On examination, he has tachypnoea, subcostal indrawing, diffuse crackles and wheeze. Oxygen saturation is 92% on room air, he is feeding poorly but maintaining hydration. According to the Canadian Paediatric Society bronchiolitis guideline, which management approach is most appropriate?