So the last time I had a severe burn patient with large and wide spread surface area involvement we used an actual combination. It is actually being implemented more and more in traumatic pain and burn pain patients. But its the combination of Ketamine and an opioid. We used morphine and ketamine and it not only refunded the patient ts pain, but practically did away with it all together. For adult patiwnts we found that works better than an opioid or than ketamjne alone. And for pediatrics the best combination for large burns was ketamine and fentanyl. I would search the use of these drugs in burn pain and trauma management. There are articles that I have seen backing us up. The national library of medicine has a few as well. Good luck.