Suggest Treatment For Developmental Delays In A Child

I am a peds occupational therapist. I see a 4 year old boy who has some developmental delays. He is also seen for speech therapy. He has a very soft voice and doesn t seem to have much respiratory reserve to speak or sing more than a phrase or two. He has very slow processing time for following directions and seems to have some motor planning problems. He is a possible candidate for an autism diagnosis. My concern is that in addition to the soft voice he has a sporadic gasp-like breathing pattern - takes in a deep breath, holds it, then exhales. I can t pinpoint any specific trigger in his environment - anxiety, excitement, etc. Sometimes he repeats it several times. While he does this he seems to disconnect from whatever else he is doing. Others involved with him think it is a self-stimming behavior. I am concerned he has respiratory issues of some sort, or could it be related to seizure activity or something else?