If it is an OBS, you code it as a single visit. One initial only, no matter how many days they are in. You need a full hour to code hydration after an injection, not 31 mintues, that is only for an initial code of hydration. I have never heard of a push lasting 30 minutes. Usually, in ER we only push a med for 5 minutes, otherwise we put a bag up and go for 30 minutes. To me, the correct coding of the scenario is 96374 and 96375. Now, if the patient has two lines established, then you can code two initials, if the physician orders mulpitle meds.