You will always get better pain control and a smoother general anesthesia if you give long-acting narcotics early (in long cases). It will prevent/diminish the sympathetic/inflammatory response. There is a reason why we say that it's much easier to prevent pain than to treat pain, after all those mediators are already circulating. Of course, the other side of the coin, the side effect, is that the patient might get oversedated; there is a fine line you'll have to learn to walk.
Giving narcotics at the beginning of/during the case (vs the end) allows you to also better gauge the patient's response and tolerance. You can fine tune the dose during the entire procedure. There is a reason this is called balanced anesthesia; we want to maximize the advantages and minimize the disadvantages of every drug. I give (long-acting) narcotics so that I can use less hypnotic agent; they usually give a faster and better wake-up than when you control pain just with hypnotic agents, and less nausea then short-acting narcotics. Similarly, I don't use muscle relaxants only to help the surgeon, or to look good because the patient does not move; I use them mainly so that I don't have to keep the patient deeper than needed.
You can balance anesthesia any way you want, not necessarily with narcotics (I use toradol whenever I can), as long as the pain control lasts after emergence. Learn to use every agent for its advantages; in case of long-acting narcotics, there is that inherent advantage of long-term pain and sympathetic reaction control. Why not use that advantage by starting the medication early enough that it lasts through the surgery, and stopping it late enough so that it lasts even after the surgery? Why expose the patients to nurse-controlled analgesia? Yes, they might be slightly more awake, but at what cost? Would you like waking up in pain after surgery?
By the time s/he hits the PACU, a patient should be both awake and pain-free. If you learn how to do that, you will enjoy every day at work. Learn from your patients, from every wake-up, from every mistake.
During my residency, I was considered "heavy handed" with narcotics just because I titrated meds to the patient's needs, regardless of what was politically correct. I once had a chronic pain ortho patient having regular surgeries. He was on the acute pain service in between, and they had a tough time controlling his post-op pain. Even the patient told me that I had no chance. He was taking about 300 mg morphine equivalent daily, at baseline. I still remember that, besides running him on low-dose ketamine, I titrated in about 20-30 mg of Dilaudid equivalent during the 2-3 hour-surgery. I would push 2 mg at a time and it would be like water. He woke up slightly groggy, pain-free for the first time in many surgeries (his words). I would do it again in a heartbeat. Of course one can argue about hyperalgesia, NMDA antagonists, gabapentin etc., but the idea here is to do what's the best for the patient, and do it early. I hate our narcomania, but that doesn't stop me from treating and preventing pain with narcotics when needed.
