Guidance on FHIR Medication resources and DM+D

0. References

1. Overview

The Care Connect Medication profiles and relationships with other profiles are shown below:

Entity Relationship Diagram showing the applied profiles.



MedicationStatement is a record of Medication that is being consumed by a patient. It is related to MedicationAdministration (record of the event where a Patient consumes or otherwise a medication) but is less detailed. MedicationOrder is a record of prescription issues, which provides detailed information and could be used with the MedicationStatement which provides summary information.

The diagram below shows the technical architecture of the Bristol scenario overlaid with Enterprise Integration Patterns EIP. The Trust Integration Engine (TIE) is collecting the patients prescriptions from a number of sources.

  • The GP source is provided by GP Connect which selects a reply from the Patients GP Practice system supplier, the response conforms to a FHIR CareConnect-GPC profile.
  • The EPR system supports CareConnect API and the response conforms to the CareConnect profiles.
  • The e-Prescribing system has an API but the response isn’t in the correct format so the TIE transforms response to CareConnect FHIR format.
  • The datawarehouse doesn’t have an API but is accessed by SQL ODBC queries, the TIE transforms the data into CareCorrect FHIR format.

Once all the data has been collated the TIE will send one response back to the Client system by aggregating all the responses. We have simplified the process of aggregation by converting all the responses to the same format.

Diagram showing an overview of the solution's architecture.



2. Working with FHIR CareConnect Medication

Most of the data servers involved within the Bristol Medication scenario will be storing data on a SQL database server. This process would be done by many of the systems discussed in the previous section (GP/EPR systems and the TIE with the datawarehouse). This is shown below, the integration middleware will retrieve data from the SQL server and transform it into a FHIR resource.

Diagram showing the breakdown of the TA.



To illustrate working with FHIR Medication resources we have listed extracts from four tables which simulate how these servers would store the data: -MedicationPatient stores the master Patient Medication record and corresponds to the CareConnect Medication Statement resource. -MedicationIssues stores the issues and is related to CareConnect MedicationOrder -Patient stores Patient demographics -Practitioner stores Practitioner information.

MedicationPatient

MedicationId Drug Name Drug Code (SNOMED CT) PatientId FirstIssue LastIssue
6b980ed2-2dc6-48e4-886d-745862fc9529 Cefaclor 375mg modified-release tablets 323803009 6a7d31db-0bb8-4afa-bf4c-c32d5d4b8487 1997-06-09 1997-06-09
6b9c746e-4cce-4f5c-a2a7-0fd156dd57ac Temazepam 20mg tablets 321153009 6a7d31db-0bb8-4afa-bf4c-c32d5d4b8487 1995-09-02 2001-08-20

MedicationIssues

IssueId Drug Name Drug Code (SNOMED CT) PatientId PractitionerId IssueDate Dosage Quantity Quantity Units Method Issue Type Duration Of Issue Private Cancelled
6bf79485-cee5-4a20-8e4a-4bf13aba33e6 Temazepam Tablets 20 mg 321153009 6a7d31db-0bb8-4afa-bf4c-c32d5d4b8487 651dfe43-26d6-49b3-b493-8955415912c7 1999-05-18T00:00:00 1on 60 tablets P R 0 false false
6bf71646-75e4-4b1c-8066-266a0af44adb Temazepam Tablets 20 mg 321153009 6a7d31db-0bb8-4afa-bf4c-c32d5d4b8487 651dfe43-26d6-49b3-b493-8955415912c7 1999-02-27T00:00:00 1on 60 tablets P R 0 false false
6bd48152-2249-430b-90d9-7b88031a1476 Cefaclor 375mg modified-release tablets 323803009 6a7d31db-0bb8-4afa-bf4c-c32d5d4b8487 651dfe43-26d6-49b3-b493-8955415912c7 1997-06-09T00:00:00 ONE TO BE TAKEN TWICE A DAY 14 tablets P A 0 false false

Patient

PatientId NHSNumber Forename Surname GP PractitionerId Gender
6a7d31db-0bb8-4afa-bf4c-c32d5d4b8487 9439676165 Karen Samson G8650149 651dfe43-26d6-49b3-b493-8955415912c7 1

Practitioner

PractitionerId GMP Code Forename Surname
651dfe43-26d6-49b3-b493-8955415912c7 G8650149 Kevin Swamp

A client system wanting to access data in the MedicationPatient table will first need to obtain the logical Id of the patient. This is achieved by querying the Patient table, we will use the Patient NHS number to do this.

GET [baseUrl]\Patient?identifier=https://fhir.nhs.uk/Id/nhs-number|9439676165

Patient in a FHIR Bundle



This would return a FHIR Bundle with one Patient resource, from the Patient resource we will extract the logicalId of 6a7d31db-0bb8-4afa-bf4c-c32d5d4b8487. We can now query the MedicationPatient table using this logical Id.

GET [baseUrl]\MedicationStatement?patient=6a7d31db-0bb8-4afa-bf4c-c32d5d4b8487

MedicationStatement's in a FHIR Bundle



This returns a FHIR Bundle containing two MedicationStatement. This may be enough for a summary screen but if we need to look in detail at a particular drug we can then query the issues using the drug code (medication), for Temazepam Tablets 20 mg the code (SNOMED Concept Id) is 321153009 (see line 30-34 in the XML sample). The Patient search parameter uses the same logical patient Id as before, note this is present in the MedicationStatement at lines 15-18. If the Patient or Practioner details are required please see details in Patient Search

Using this Patient Id and including the Concept code the query is:

GET [baseUrl]\MedicationOrder?patient=6a7d31db-0bb8-4afa-bf4c-c32d5d4b8487&code=http://snomed.info/sct|321153009

MedicationOrder's in a FHIR Bundle



This results in a FHIR Bundle which contains two MedicationOrder. Note: consider including a date parameter to limit the amount of results returned.

3. Creating FHIR CareConnect Medication’s in code

The code below shows how the same three queries can be done in java.

[TODO Validate code]

Java examples for creating FHIR MedicationOrder and MedicationStatement resources based on the MedicationIssues and MedicationPatient tables can be found on GitHub.