Hopefully someone here will have a bit more info that what I do, but you definitely should not be charging under a Rev Code 450 with ER EM levels.

Rev Code 762, observation, is more appropriate to what you are doing. Procedures such as a NST are coded and charged for separately, so they will still be listed. Doesn't your facility have a team that reviews chargemasters (price files) that can assist you with this? This needs to be a team effort between your reimbursement dept, coding and yourself.

I believe the other depts should be doing the research and helping you set this up, not leaving it to you do to, as quite frankly, when I had to fix what nurses did to the chargemaster...it was scary. You DEFINITELY should have assistance from those that are telling you to change this (one of my complete sore spots, I feel like the other depts are dropping their responsibilities here!).

I haven't looked at an OB triage chargemaster in a few years, so Im way rusty on it...sorry I can't help more!
Shannon