Observation (Vital Signs)

Description

Creates an Observation resource to record vital sign measurements for a patient within the EHR. This API is used to insert vital readings into the patient chart under a specific encounter. The encounter must be an existing open encounter, and the request will be rejected if the encounter is closed or signed off.

Each request records one vital sign reading at a time. The system will only insert new values and will not update existing vital records. If a reading already exists for the same vital sign at the same timestamp, the request will be rejected. The Observation ID is always generated by the FHIR server, and any client-provided ID will be ignored.

Vital signs must be coded using LOINC codes, mapped from the EHR Vital Options configuration using the external ID. Supported vital types include measurements such as body temperature, heart rate, respiratory rate, blood pressure, oxygen saturation, body height, body weight, BMI, pain score, and other standard clinical vitals.

Each observation must reference the patient (subject) and the encounter where the vital was recorded. The effectiveDateTime represents the time when the measurement was taken. Optionally, the observation may include the performer who recorded the vital sign.

For composite vital signs such as blood pressure, the observation uses components to record multiple values (for example, systolic and diastolic pressure). Components may also be used to record measurement site information, such as the location of temperature measurement or the anatomical site used for heart rate or blood pressure readings.

All vital measurements must use standard UCUM units (for example kg, mmHg, %, /min, °C, or °F) to ensure consistency across integrations.

Interaction:

POST Request

HTTP Method: POST

curl -X POST "{{url}}/mps/fhir/R4/V1/Observation/" \
  -H "Authorization: Bearer {{token}}" \
  -H "Content-Type: application/fhir+json" \
  --data-raw '{
    "resourceType": "Observation",
    "meta": {
      "profile": [
        "http://hl7.org/fhir/us/core/StructureDefinition/us-core-vital-signs"
      ]
    },
    "status": "final",
    "category": [
      {
        "coding": [
          {
            "system": "http://terminology.hl7.org/CodeSystem/observation-category",
            "code": "vital-signs",
            "display": "Vital Signs"
          }
        ]
      }
    ],
    "code": {
      "coding": [
        {
          "system": "http://loinc.org",
          "code": "8310-5",
          "display": "Body temperature"
        }
      ],
      "text": "Body Temperature"
    },
    "subject": {
      "reference": "Patient/Patient-265"
    },
    "encounter": {
      "reference": "Encounter/Encounter-805"
    },
    "effectiveDateTime": "2025-06-12T09:00:00Z",
    "valueQuantity": {
      "value": 37.2,
      "unit": "Cel",
      "system": "http://unitsofmeasure.org",
      "code": "Cel"
    },
    "component": [
      {
        "code": {
          "coding": [
            {
              "system": "http://loinc.org",
              "code": "80313-7",
              "display": "Site of body temperature measurement"
            }
          ],
          "text": "Measurement Site"
        },
        "valueCodeableConcept": {
          "coding": [
            {
              "system": "http://snomed.info/sct",
              "code": "263688005",
              "display": "Oral cavity structure"
            }
          ],
          "text": "Oral"
        }
      }
    ]
  }'

Observation (Vital Signs) Resource Content

Response Codes

Product Information

IMS (14.0.SP1)