Can a physician obtain records about a patient from another physician without the patients consent?

What you are undoubtedly referring to are HIPAA concerns.  Under HIPAA privacy rules, covered health care providers are allowed to share protected health information for treatment purposes without patient authorization, as long as they use reasonable safeguards when doing so. These treatment communications may occur orally or in writing, by phone, fax, e-mail, or otherwise. For example, a lab can fax a report to a referring physician. Your regular doctor can speak with a specialist to whom you were referred and vice versa.  If you do not think that this is what refers to you here then write back. Please be more fact specific when you do.  Thanks.