Suggest Treatment For Asthma And Respiratory Distress

Question : I am a nurse in Well Baby Nursery, have a nephew who is 7 months old. He failed CCHD screening after birth, had desats with feedings, and was on oxygen for 4+ days. He has had wet lungs since delivery, on a good day he has mild to moderate retractions and little nasal flaring. On bad days he is grunty and retractions get worse. Pediatrician diagnosed him with asthma, but steroids didn't ever seem to work. An echo was never done even though he failed CCHD. He was hospitalized (at 2 months old) for 2 weeks with bronchiolitis, went home on oxygen and pediatrician was unable to wean him off until 3 weeks later but he was barely satting in low 90s (5 wks of supplemental oxygen). During his hospital stay a chest xray was done and showed dilated pulmonary vessels, but nothing else was done, he was just on oxygen and was suctioned out every few hours. Repeat chest xray ordered by PCP after a few weeks was "about the same" per PCP. The infant is unable to lay on his belly because he acts like he has a hard time breathing, sometimes at night his sats drop to the 80s. He appears to be in respiratory distress pretty much every day but pediatrician says he is fine. What now?