I am a bit worried about Wren so I called the cardiology clinic and spoke to the nurse. The problem is not really that he wakes so often in the night but that he is so sluggish in the daytime. Its now 5pm and since I woke this morning he has had only one significant wakeful period (of 2 plus hours - quite a bit fussing). The rest of the time he naps, nurses for 5 minutes and sleeps deeply, then wakes to the grunting and looking around occasionally stage, then nurses for a short period (or a few short periods) and naps again, poops again and wakes for a short while etc. Other than diaper change and a few breaks of alert time of 10 minutes or so he has been asleep!
I asked the cardiology nurse about his behaviour and she feels there is nothing worrying enough to bring him in before his scheduled echo on Monday but that the frequency and short duration of his regular nursing is a concern. She had a few ideas - that he is tiring after a short period, that he is day-night reversed (apparently more common after long hospital stays), that he is disturbed by reflux so nurses till only a bit full or that he has colic (not). That he is not struggling to nurse, not sweating or doing anything else odd is a good sign but she wants to check his breathing as well as rapid breathing can be another sign of "working too hard".
She said that they will evaluate him after the echo but really want him to nurse in a more "normal" way. I am not so concerned about normal but I want a more alert baby. He worries me this way. His breathing has always been fast so I am not sure how they are going to make sense of that one.