Page him every 15 minutes until you get an answer, if it takes more than 4 pages go up the chain of command. Document all pages.
If his decisions are inappropriate express your concerns to him. If he doesn't respond appropriately, go up the chain of command. Document your conversations.
If he says he's coming right over and doesn't show up page him again just to make sure he wasn't in a car wreck (
) If he still doesn't show up, go up the chain of command.
There has to be a medical head of the department, or hospital, and that's part of their job- to make sure the docs on staff don't kill anyone. If you need to contact the department head leave a message for your manager as an FYI. Likely someone will complain to her about what mouthy employees she has, and she'll appreciate the heads up.
Keep a copy of documentation about the issues you called about and the responses in case nothing changes and you choose to report him to the medical board. It gives you more credibility if you can show them how you addressed the problem internally before going to them.