We’ve recently updated our pain management guideline to include Ketamine in addition to IV opioids for severe pain.
Here’s a marvellous post from the Skeptics’ Guide to Emergency Medicine that should give you a better understanding of where the evidence is, and why this is an outstandingly good idea;
Be sure to scroll all the way to the end where you’ll find a couple of ‘paper in a picture’ graphics that summarise the literature !