Scenario:  Clinical Solution A Requests Patient Summary-CA On Demand from Clinical Data Repository

Assumption:  Clinical data used to generate the Patient Summary is retrieved from sources that are internal and/or external to the Clinical Data Repository

Implementation Option:  This sequence diagram provides the option of using the CA:FeX Interoperability Specifications that provide support for requesting a Patient Summary-CA on demand from a Clinical Data Repository (Local to PS-Producer or Central). This profile includes a Data Consumer and a Data Responder actor. Additionally, this sequence diagram uses the 'Fetch DocumentReference' CA:FeX-2B transaction which is based on $docRef.

This implementation option is suitable for systems where the discrete FHIR resources needed to generate the Patient Summary are either external to the Clinical Data Repository generating the summary, or distributed across various internal and external data sources.

The on-demand Patient Summary generation occurs in two steps and involves asynchronous processing when data retrieval has longer response times, which is typically the case for external data sources. In the first step, a DocumentReference resource is created, that contains the location where the Patient Summary document is or will be available. The retrieval of the discrete FHIR resources needed to assemble the Patient Summary document is an asynchronous operation. In the second step, the on-demand Patient Summary document is retrieved once the assembly of the discrete FHIR resources is complete.

Note: Additionally, this sequence diagram includes the CA:FMT Interoperability Specifications that handle transformations to and from various formats (e.g. FHIR to PDF, CDA, etc.). Additional details will be included in the PS-CA Interoperability Specifications.

Sequence Diagram Overview: 

Below provides guidance on how to read the sequence diagram:  

• This sequence diagram illustrates how the different standardized actors of systems should interact with each other to carry out specific standardized transactions, and the order in which the transactions and interactions occur when Use Case 4 of the Patient Summary-CA is executed.
• The legend on the bottom right corner describes the different system components, actors and transactions that are necessary to carry out this particular use case. 
• The green swim lane is a simplified view of the actors and transactions required by the Foundational Profiles, defined here, in addition to the other ones that are not explicitly illustrated on the diagram (e.g. ATNA, CT) but included as a white note. These are pre-requisite conditions for this particular use case and it is assumed that these will be satisfied. 
• The blue swim lanes groups sequence of processes (along with their required actors and transactions) that are needed to occur to satisfy this particular use case. These are to be read from left to right and top to bottom. 
• The red note boxes describe important call outs, information and notes that provide more context for the sequence diagram. 
• This sequence diagram includes the CA:FeX Interoperability Specifications and CA:FMT Interoperability Specifications. Additional details will be included in the PS-CA Interoperability Specifications.
• For more information on core IHE Profiles and specific Canadian implementation guidance, refer to the Reference Architecture.