I am a senior BSN student, so take my comments/advice with a grain of salt! I am currently on a Neuro Trauma ICU at a level one trauma center - not quite the ED, but still a critical care environment with frequent changes in patients health status and a need for med modifications.
From my personal experience, as a student nurse, and working with my preceptor - nurses are expected and encouraged to actively participate in rounds and recommend to hold/give certain medications based on their thorough assessments. In the ICU, we are assigned 1-2 patients, depending on acuity, and are continually involved in making recommendations in our patients care. Attendings and residents make their rounds and ask how their patient is doing, any important updates, and if we have any recommendations to treatment. My preceptor and I (as well as all of the other nurses on the unit) are constantly asking, inquiring and recommending various medications and treatments. The physicians are very receptive to this and unless they blatantly disagree with our assessment and/or treatment inquiry, our "requests" are "approved". It's truly a team-oriented and multidisciplinary approach, which benefits our patients as the nurses are the eyes and ears at the bedside.
As a student, I've recommended holding a diuretic based on soft pressures, pulling a K+ after my patient has dumped excessive amounts of urine for more than a couple hours, asked for a sedative for an intubated patient who was dysynchronus with their vent. I've asked for versed pushes for a patient excessively coughing and fighting their vent, then later asked for propofol when the versed was not proving to be helpful. I've asked for blood cultures on a patient with a steadily increasing temperature, after non-pharmacologic interventions and tylenol had been implemented.
Long story short, I absolutely believe you should be inquiring/asking/recommending various medications and treatments - especially if there is changes in patient status, or if your knowledge and assessment of your patient leads you to believe so. Of course, the way you word your question and your tone is everything, and demanding orders is not the way to go about it. But if you are genuinely inquiring and have sound reasoning (poor hemodynamics -low pressures, tachycardia, high temperature, violent behavior, excessive coughing, etc), they should listen and appreciate your advice. I think the key here is having your facts together, numbers when possible, and having that strong reasoning behind your recommendation. ( Also isn't a bad idea to phrase it in a way that makes them feel like it's their idea ;-) ) If they're a competent physician who prioritizes patient care and feels the nurse is an integral part of the health care team, they will consider your advice and will also kindly accept or refuse and explain why. Hope this helps! - Brianna