Christina Laun at RN Central has made a helpful list: 25 Tips to Help Protect Yourself from Medical Errors.
Reading the entire list is a good idea. But many of the items on the list can be boiled down to two principles: 1) be an active participant, and 2) don’t be afraid to seem entitled or pushy in demanding knowledge of what is going on. Don’t be afraid you’re annoying your doctor by asking questions, for instance. Speak to every member of your surgery team and make sure they know what they’re doing–do not simply trust, and remember that there is no reason to feel ashamed or embarrassed about asking questions.
Furthermore, bring family or friends to support you, if you can. If you’re ill, you may not be able to do the things on the list yourself. Having someone to ask the questions you don’t think of and notice the things that you don’t notice is an invaluable asset.