Searches Using Patient ID

[Steve Clark]

I will use the following example to ask my questions. Let's say you want to get the oral temperatures for a patient. To do this, you will use an Observation query (see http://fhir.cerner.com/millennium/dstu2/diagnostic/observation/#parameters). For example: https://fhir-open.sandboxcerner.com/dstu2/0b8a0111-e8e6-4c26-a91c-5069cbc6b1ca/Observation?patient=3998008&code=http://loinc.org|8331-1

Following are my questions:

1. In the example above, the Patient ID is 3998008. What exactly is this ID? Is it simply an autonumber field (like an Oracle Sequence)?
2. Is there any way to query using MRN or FIN? If so, how?

[Jenni Syed (Cerner)]

For FHIR purposes, the id is just a unique id for the Patient resource, and must be considered opaque. No assumptions other than that should be made about the id string. See: http://hl7.org/fhir/dstu2/resource.html#id For example, we could start using GUIDs in future FHIR versions and it should have no impact on apps.

MRN and FINs are identifiers: http://hl7.org/fhir/dstu2/resource.html#identifiers

MRN is a patient identifier, which we do support searching by: http://fhir.cerner.com/millennium/dstu2/individuals/patient/#search (note: you would need to know the organization's OID to query)

FIN is an encounter identifier, which we currently do not support searching by: http://fhir.cerner.com/millennium/dstu2/encounters/encounter/#search

Depending on what type of application you're building, if it can be launched from a patient chart, there would be no need to search for a patient or encounter - those would be provided as part of the SMART workflow: http://docs.smarthealthit.org/authorization/scopes-and-launch-context/#launch-context-arrives-with-your-access_token 

~ Jenni

[Steve Clark]

So, if my app is being launched as an MPage, I will have access to MRN, FIN, and Encounter ID?

I am using the example in the Cerner documentation (see http://fhir.cerner.com/millennium/dstu2/individuals/patient/#example) for the following.

Will this (retrieval by MRN): https://fhir-open.sandboxcerner.com/dstu2/0b8a0111-e8e6-4c26-a91c-5069cbc6b1ca/Patient?identifier=urn:oid:1.1.1.1.1.1|10002701

get the exact same result as this (retrieval by Patient ID): https://fhir-open.sandboxcerner.com/dstu2/0b8a0111-e8e6-4c26-a91c-5069cbc6b1ca/Patient?_id=4342009 ?

[Jenni Syed (Cerner)]

If your app is launched as a SMART application within PowerChart, it will be given the FHIR patient id and FHIR encounter id specifically as part of the OAuth token response - the app wouldn't look it up by MRN and FIN.

As to your examples: yes, right now, those two URLs return the same results. You should be able to test this out using curl or a Rest app like Postman [1].

[1] https://www.getpostman.com/

[Steve Clark]

Is the FHIR encounter ID the same as the ENCNTR_ID stored in the ENCOUNTER table in Cerner's Oracle DB?

[Jenni Syed (Cerner)]

It is right now, but that should not be assumed as we can change it in future versions.