It will be more reasonable:

Conversation Analysis (CA): This is a foundational theory for analyzing talk in interaction. It focuses on the structure and organization of conversation, including turn-taking, repair mechanisms, adjacency pairs, and overall patterns of interaction.

plz see Vygotsky theory and narrative inquiry

Philosophical basis is important for correct approaching to patient-physician relationship.

Review some hermeneutical approach to medicine, physician , and patient.

Such relation should be analyzed under ontological, epistemic, and semiotic perspective because patient-physician relation not only is a horizontal but also is a vertical discourse.

You can review Conversation Analysis or Discursive Psychology. Depending on what you intend to address, you may consider reviewing Membership categorization analysis, positioning theory, politeness theory, or communication accommodation theory.