question

I've heard of modelers using a repeating global process activity with the Custom Activity Option called Initiate Patient Rounds executed in the activity's Activity Finished Trigger. The Repeat Interval of the activity can be used to control the frequency of the call light interrupts. The requirement that the room must be occupied is an option of the Patient Rounds function and you can specify another requirement such as bernoulli(25, 1, 0) to model a 25% probability that any given patient would need to be attended to.

As for the staff requirement, you can simply use an Alternate Group to specify your possible staff assignment because in the case of an RN being used, you want to use the RN who was used previously in a particular activity of the patient being attended to. This will require you writing your own script for assigning a staff member to global activity. In your script, you can reference the current location being evaluated by the Patient Rounds function with the variable name curloc and you can reference the patient who is in the current location as first(curloc).