It is common practice for hospital patients to sign a consent form giving the doctor their approval to perform surgery. Through the form, the patient usually consents to the specific surgery, as well as to any other procedures that might become necessary. Prior to signing the document, your doctor should give you a complete description of the surgery and the risks involved, as well as the consequences of not getting the treatment. If you can prove your doctor incorrectly described the facts or failed to adequately tell you about the risks and benefits before surgery, your consent may not be valid.