Healthcare Interoperability with FHIR

What is FHIR?

FHIR (Fast Healthcare Interoperability Resources) is a standard for exchanging healthcare information electronically. When building Kera Health, FHIR compliance was essential for interoperability with other healthcare systems.

Why FHIR Matters

Healthcare data is fragmented across systems that don't talk to each other. FHIR provides:

Standardized data formats

RESTful API patterns

Resource-based architecture

Modern web standards (JSON, OAuth)

Implementation at Kera Health

Resource Mapping

We mapped our internal models to FHIR resources:

| Internal Model | FHIR Resource |

|---------------|---------------|

| User | Patient |

| Doctor | Practitioner |

| Consultation | Encounter |

| Prescription | MedicationRequest |

API Endpoints

Standard FHIR endpoints follow predictable patterns:

GET /Patient/{id}

POST /Patient

PUT /Patient/{id}

DELETE /Patient/{id}

GET /Patient?name=John

Search Parameters

FHIR defines standard search parameters:

# Example: Search patients by name

@api.get("/Patient")

def search_patients(name: str = None, birthdate: str = None):

queryset = Patient.objects.all()

if name:

queryset = queryset.filter(

Q(given_name__icontains=name) |

Q(family_name__icontains=name)

)

return FHIRBundle(queryset)

Challenges

Data Transformation

Converting between internal representations and FHIR format requires careful mapping. We created transformer classes for each resource type.

Partial Compliance

Full FHIR compliance is complex. We prioritized the resources and operations most relevant to our use case.

Performance

FHIR's verbose format can impact performance. We implemented:

Response compression

Pagination

Selective field inclusion

Results

With FHIR implementation:

Integration with partner systems became straightforward

Data export for patients was standardized

Regulatory compliance improved

~25 endpoints serving healthcare data

Lessons Learned

Start with core resources only

Use existing FHIR libraries when possible

Test with FHIR validators

Document deviations from standard

FHIR isn't simple, but it solves real interoperability problems in healthcare.