"They're putting him on full life support this morning to stabilize him for a valve-opening procedure tomorrow. The biggest risks will be weaning him from it in a couple days. St. Joe, pray for us."
Having spoken to Pat a little more in depth last night we know that the mis-functioning valve is the problem that is causing his blood pressure to drop to such dangerous levels. His poor little body is just not able to support all of the vital organs enough to stabilize him for the necessary surgery but going on full life support means that his body won't be as quick and sharp and able to adjust as it is now, hence the danger being weaning him off in a couple days.
Pray for Pat and for Kate. They are strong and have family support and priestly consolation but this is a very hard road to walk down.