For the longest time we've gone by U/O and then eventually use CVP. As of recently however, we have been using PiCCO. Certain attendings love it. It's a pain in the butt to gather all the supplies as we don't stock them everywhere and it's a scavenger hunt to find the catheters, transducers, etc. but once it's set up, I do find that it's helpful in directions f our fluid goals.