All of these devices are tied to Teag's through IV's. They have incredibly skilled nurses that watch EVERYTHING soooo closely. His nurses are all cardiology specialists, they are so amazing. We love them and are so grateful for their countless ours of sleepless nights and long days. They said their is no "recipe" for each patient, it is up to them to tweak these medications as they feel it is needed and as the monitors tell them. I know they are prompted to do what they do.