William is a four year old boy who you have seen a few times over the last few months with a nocturnal cough. He had generally been well during the day with no cough or episodes of wheeze. William’s mum has brought him in to see you today as she is concerned about an increased Salbutamol requirement (three times in the last ten days) and is worried about him becoming unwell at night and not being aware. She informs you that he has not had any intercurrent illnesses or been in contact with any sick children. On examination today, William is speaking in full sentences, his respiratory rate is 20 and has a faint expiratory wheeze. He is unable to do a peak flow.
He was born at term with normal vaginal delivery, he is up to date with immunisations and meeting his developmental milestones. William has had three episodes of viral induced wheeze over the last year and has mild Eczema. What is the most appropriate next step?