Webhook Lab Results to FHIR R4 Observations (LOINC) + Slack Alerts

Send lab results to FHIR R4 Observations (LOINC) and get instant Slack alerts for critical values

This n8n workflow accepts lab results via a /lab-result webhook, validates and maps each test to a LOINC-coded FHIR R4 Observation, saves it to your FHIR server with duplicate protection, and can notify your team in Slack when a result falls into a configurable panic range—without including patient identifiers in alerts.

What this workflow does

• Receives lab results through a POST request on the /lab-result webhook with a JSON payload.
• Validates required fields and formats (including ISO timestamps) and normalizes the test identifier.
• Maps tests to supported LOINC codes and expected units, then enriches the Observation with configurable reference and panic ranges (demo examples are configurable).
• Prevents duplicates using an idempotency key, returning early if the result was already processed.
• Creates a FHIR R4 Observation linked to Patient/{patient_id} and sends the request with an If-None-Exist header to avoid re-creating the same Observation.
• Triggers Slack alerts for critical results when the value is within the configured panic range and Slack alerts are enabled—posting a critical alert without patient identifiers.

Use cases

• Route incoming lab results from a lab system or app to a FHIR R4 clinical repository.
• Ensure Observations are consistent by enforcing LOINC mapping and expected units.
• Operational monitoring for critical lab findings using Slack notifications with no patient identifying details.
• Build reliable, repeatable ingestion with webhook validation and duplicate protection.

Technical details

• Webhook: POST endpoint at /lab-result
• Nodes/logic: if, set, code, webhook, sticky note, http request
• FHIR integration: requires a reachable FHIR R4 base URL; posts an Observation linked to Patient/{patient_id} using HTTP If-None-Exist
• Optional auth: configure a Bearer token (or other HTTP auth) if needed
• Slack integration: sends critical alerts when panic-range conditions are met