Is it permissible for a muslim male doctor to touch and examine a female patient (muslim/non) as part of his profession? In todays time it is difficult to practice in a segregated setting as a doctor especially when he practices in a hospital where both male & female patients would be coming to him

The default is that women are treated by women. A male doctor may examine a woman, Muslim or not, only when no female doctor is available to do it, looking at and touching only what the treatment needs, and never alone with her, as Imam Ibn Baz and Shaykh Ibn Uthaymin said. Shaykh Ibn Uthaymin added that It is wājib (obligatory) upon the hospital administration to pay attention to this. So, if the administration does not carry out this obligation upon it, and does not care, then there is no harm in you examining women. But on condition that there is no khalwah (being alone together in private) or desire, and also that there is a need for the examination.