US Core Implementation Guide (Release 1)

This page is part of the US Core (v1.0.0: STU1) based on FHIR R3. The current version which supercedes this version is 5.0.1. For a full list of available versions, see the Directory of published versions

D.4.1 StructureDefinition-us-core-vitalsigns

This Implementation Guide uses the Vital Signs Profile formal definitions from the FHIR Observation resource. However, this Implementation Guide provides the following additional guidance which sets the minimum expectations for recording, searching and fetching vital signs associated with a patient. Together they identify which elements, extensions, vocabularies and value sets SHALL be present in the resource when using this profile.

Example Usage Scenarios:

The following are example usage scenarios for the Vital Signs Profile:

  • Query for vital signs of a particular patient
  • Record vital signs of a particular patient
Mandatory Data Elements and Terminology

The following data-elements are mandatory (i.e data MUST be present). These are presented below in a simple human-readable explanation. Profile specific guidance and examples are provided as well. The Formal Profile Definition are provided as links in the table below to view the formal summary, definitions, and terminology requirements.

Each Observation must have:

  1. a status
  2. a category code of ‘vital-signs’
  3. a LOINC code which tells you what is being measured and is taken from the “LOINC Code” column in the table below.
    • note: If a more specific code is recorded, the generic code and the translated coded must be sent - e.g. method specific LOINC Codes, SNOMED CT concepts, system specific codes
  4. a patient
  5. a time indicating when the measurement was taken
  6. a numeric result value and standard UCUM unit which is taken from the “UCUM Unit Code” column in the table below.
    • note: if there is no numeric result then you have to supply a reason

Profile specific implementation guidance:

  • This table represents a minimum set of vital sign concepts, the required LOINC codes, and UCUM units of measure codes used for representing vitals signs observations (See the General Guidance Section for further guidance on using UCUM). These are extensible bindings and require that when a system support of any of these vital signs concepts, they must represent them using these codes. In addition, if you have a blood pressure observation, you must have both a systolic and a diastolic component, though one or both may have dataAbsentReason instead of a value.

  • This profile may be referenced by different capability statements, such as the Conformance requirements for the US Core Server.

  • Alternate codes may be provided in addition to the standard LOINC and UCUM codes defined here.The examples illustrate using other codes as translations.

  • Other profiles may make rules about which vital sign must be present or must be present as part of a panel.

Examples

D.4.1.1 Formal Views of Profile Content

Vital Signs Profile : Link to the requirements summary and definitions and terminology requirements for the vital signs listed in this table.

The first column of this table links to the formal views of the individual profile for each vital sign.
Vital Sign Name LOINC Code LOINC Name and Comments UCUM Unit Code
Vital Signs Panel 85353-1 Vital signs, weight, height, head circumference, oxygen saturation and BMI panel - It represent a panel of vital signs listed in this table. All members of the panel are optional and note that querying for the panel may miss individual results that are not part of the actual panel. When used, Observation.valueQuantity is not present ; instead, related links (with type=has-member) reference the vital signs observations (e.g. respiratory rate, heart rate, BP, etc). Note that querying for the panel may miss individual results that are not part of an actual panel. This code replaces the deprecated code 8716-3 - Vital signs which is used in the Argonaut Data Query Implementation Guide. -
Respiratory Rate 9279-1 Respiratory Rate /min
Heart rate 8867-4 Heart rate - To supplement this vital sign observation, 8887-2 - Heart rate device type MAY be used as an additional observation. /min
Oxygen saturation 59408-5 Oxygen saturation in Arterial blood by Pulse oximetry - This code replaces the deprecated code 2710-2 - Deprecated Oxygen saturation in Capillary blood by Oximetry which had been listed in C-CDA. %
Body temperature 8310-5 Body temperature - o supplement this vital sign observation, 8327-9 - Body temperature measurement site (oral, forehead, rectal, etc.) and 8326-1 -Type of body temperature device MAY be used as additional observations Cel, [degF]
Body height 8302-2 Body height cm, [in_i]
Body length 8306-3 Body height --lying - Like height, but lying down, typically this is used for infants cm, [in_i]
Head circumference 8287-5 Head Occipital-frontal circumference by Tape measure cm, [in_i]
Body weight 29463-7 Body weight - To supplement this vital sign observation, 8352-7 - Clothing worn during measure and 8361-8 - Body position with respect to gravity MAY be used as additional observations. g, kg,[lb_av]
Body mass index 39156-5 Body mass index (BMI) [Ratio] kg/m2
Blood pressure systolic and diastolic 55284-4 Blood pressure systolic and diastolic - This is component observation. It has no value in Observation.valueQuantity and contains at least one component (systolic and/or diastolic). To supplement this vital sign observation, 8478-0 - Mean blood pressure, 8357-6 - Blood pressure method, 41904-4 - Blood pressure measurement site, 8358-4 - Blood pressure device cuff size, 41901-0 - Type of blood pressure device MAY be used as additional observations. -
Systolic blood pressure 8480-6 Systolic blood pressure - Observation.component code for a blood pressure Observation mm[Hg]
Diastolic blood pressure 8462-4 Diastolic blood pressure - Observation.component code for a blood pressure Observation mm[Hg]

D.4.1.2 Quick Start

Below is an overview of the required search and read operations for this profile. See the Conformance requirements for the US Core Server for a complete list of supported RESTful operations and search parameters for this IG.

GET [base]/Observation?patient=[id]&category=vital-signs

Example: GET [base]/Observation?patient=1186747&category=vital-signs

Support: Mandatory to support search by category code.

Implementation Notes: Search based on vital sign category code. This search fetches a bundle of all Observation resources with category ‘vital-signs’ for the specified patient (how to search by reference) and (how to search by token). The table above is the minimum set, additional vital signs are allowed.


GET [base]/Observation?patient=[id]&code=[vital sign LOINC{,LOINC2,LOINC3,...}]

Example:

  • Search for all heart rate observations for a patient:
    • GET [base]/Observation?patient=1186747&code=8867-4
  • Search for all heart rate, respiratory rate and blood pressure observations for a patient
    • GET [base]/Observation?patient=1186747&code=8867-4,9279-1,55284-4

Support: Mandatory to support search by vital sign LOINC(s) listed above.

Implementation Notes: 1)Search based on vital sign LOINC code(s). This fetches a bundle of all Observation resources for specific vital sign(s) listed in the table above for the specified patient (how to search by reference) and [how to search by token)]. 2) The Observation “code” parameter searches both in both Observation.code and Observation.component.code. For example when fetching blood pressures the same resources will be returned whether the search is based on 55284-4(Systolic and Diastolic BP), or the component codes 8480-6(Systolic BP) or 8462-4 (Diastolic BP).


GET [base]/Observation?patient=[id]&category=vital-signs&date=[date]{&date=[date]}

Example:

  • Find all the blood pressures after 2013-03-14
    • GET [base]Observation?patient=555580&code=55284-4&date=ge2015-01-14

Support: Mandatory to support search by category code and date

Implementation Notes: Search based on vital sign category code and date. This fetches a bundle of all Observation resources with category ‘vital-signs’ for the specified patient for a specified time period (how to search by reference) and (how to search by token).