Hi Ernie,
Hope your wife recovers quickly and goes home tomorrow.
As you may know my husband was home trached/ vented for four years and I took his O2 sats multiple times a day. The two things that would give us scary O2 numbers were cold hands and irregular heart beat ( he had a lot heart issues). If his hands were cold I would warm them up with a blanket or heating pad and be amazed how quickly his sat recovered !
Hope this helps for future reference, Kate