Calling all experienced trach/vent moms..confusing child here

[TeraNicole]

Hey everyone! I have a very confusing situation and I think the ped is as stumped as I am. Bear with me, this is going to be long.

It all started six weeks ago Zachary started on medication for hypothyroid. Two weeks after starting the medicine, wierd things started to happen. First, the oximeter started to alarm saying his sats had dropped, sometimes down into the 70's, yet he looked fine to me. I could mess with him or it and it would come back up. So I thought I had a faulty machine and just dealt with it for a couple of weeks until I asked Apria to bring me another. I got the second oximeter about 3 weeks ago. Right after I got it he got sick. He had bright red bloody secretions and a trach culture came back with proteus mirabilis and ecoli. He did 10 days of Augumentin and started to act like he was better but the oximeter was still acting up. This is where it gets confusing. For the last 4 weeks he has also had alot of swelling in his legs and feet which I know now was a side effect of his thyroid medicine. Thats a side note I guess. So a few days ago the bloody secretions are back and he's acting sick again. Take him to the ped for tests because I am clueless. His sats are awful and he's on 2 liters just to get a 92. Zachary is normally room air. His Co2 is excellent at 29, his xray is clear as a bell and his lungs sound good. His white count was normal so he can't be sick. If he was, his Co2 would be up. The only things we found were hemoglobin was low at 9 so he's anemic and his platelets are very low which explains the bloody secretions. His urine was clean of everything and normal. But his sodium was up. The ped says that she thinks he's a little dehydrated, even though his urine was not concentrated and she wants me to do another 10 days of Omnicef because she thinks there may actually be something on his xray that we cant see. I just dont buy that. I dont think he could be sick with a great Co2 and clear xray. But then why in the heck are his sats so bad? We did another trach culture so we'll see what it says but I just dont buy that he's sick. His vent settings seem good since his Co2 is good but whats going on with his sats? Also, he shouldn't be retaining fluid by swelling if he's dehydrated.

Is everyone confused yet? I am and I dont know what else to try for him. I went ahead and started the Omnicef but I just dont think thats is. He doesn't seem sick now. He's been smiling and laughing. Secretions are normal white/clear and the only issue other than the sats are his allergy runny nose.

Does anyone have a clue? Any ideas what I can ask to be tested?