Busy days ahead it seems

For fear of jinxing things..yesterday was a reasonably calmer day. We seem to have these "uneventful" periods where other than some belly breathing and a little congestion, he seems fine... and then I see him out of the blue have heart rate drop like lightening and I realize we have to get to the bottom of this. Those also seem to come in a series and best that I can tell are usually when asleep or resting. They are planning to do a muscle biopsy soon and they want alot of blood for lab tests this morning..ugh..and they are doing an MRI tomorrow of his throat upper chest area?? I said.. why there? He has already had cts of that area and x ray.. well apparently they are looking to check for any nerve issues. I slept from midnight to 4 which is probably longest all week but am beginning to feel really out of it.. can't even form clear thought bumbling with his wires just trying to hold him but feeling so tired and disoriented. I need more sleep but how can I check out with him doing this? How will I ever sleep at home if this is still happening then? I don't know if they will order for nursing in the evenings or something but I can't keep this mode up and what if I don't hear the alarms..? This happened one night this week when Sam was having more episodes..we were so exhausted finally crashing and then when I checked on Sm his moniter showed he had a low heart rate alarm that I had missed..I know usually he self corrects on his own..but those few times he has not and went on down down to like 30 heart rate is absolutely shocking...well.. better try to close my eyes for a minute while sam is back to sleep.