# Save vitals to a patient's chart

You can use this API action to save recorded values or measurements to an EHR system after a patient encounter. This is for specific values, not provider notes or interpretations. If you want to store a note with the result, [save a diagnostic report to a patient's chart instead.](/fhir-api-actions/results-and-vitals/save-vitals-to-a-patients-chart)

With this API action, you’re writing data _to_ your connection’s system, not receiving data. Think of this like reporting an update that your organization recorded about a patient. 

> **Prerequisite: Having a patient identifier**
>
> To use this API action, you must know the patient identifier. If you don’t have one, [search for a patient with demographics](/fhir-api-actions/patients/search-for-a-patient-by-demographics) to locate an appropriate identifier first.

## Use cases

This API action may be a good fit for your organization if you perform any of these use cases:

- Save patient vitals from devices to a patient’s chart (e.g., blood pressure measurements from a blood pressure cuff or pacemaker readings).
- Record a patient’s physical characteristics (e.g., weight, height).
- Save social history information (e.g., tobacco/alcohol/drug use).

## Supported systems

You can use this API action with the Redox FHIR API. 

> **Talk to a Redoxer**
>
> It’s also possible to use the Redox Data Model API for this API action. [Talk to a Redoxer](https://redoxengine.com/forms/contact-us/) to learn about your options.

Your connection's system can receive and process writeback messages with their own FHIR or proprietary API or an HL7v2 feed.

## Things you need to know

<details>
<summary>Related encounter</summary>

If you’re saving patient vitals recorded during a patient visit, you'll likely need to include the related encounter ID.

</details>

<details>
<summary>Clinical observations</summary>

Patient vitals are generally a measurement taken during a patient visit (e.g., blood pressure measurement). However, recorded vitals could also be an observation during a patient visit. For example, you may want to save an observation related to a patient’s social history during a patient visit.

</details>

<details>
<summary>Lab results vs. patient vitals </summary>

Lab results are a one-time outcome of an order. Whereas patient vitals are values from device readings, which are typically continuous measurements (e.g., ventilators, pumps, Sp02 monitors). Lab results may also come from devices (e.g., imaging), but the device doesn’t measure or capture results continuously.

> **Data models for lab results and vitals**
>
> If you're saving data via the Data Model API, use the `Device` data model for patient vitals and the `Results` data model for lab results.

</details>

<details>
<summary>What to include with writeback messages</summary>

When you write data back to an EHR system, you should always include whatever data points you have. You can think of this like including a patient’s demographics for a new patient record; the demographics give useful context for the patient’s chart. 

This “demographics” concept is the same for any new “thing” you’re saving to an EHR system. When sending a writeback message, you should include any relevant identifiers, codes, or context to tell the EHR system about the data you’re saving. Here are some examples: 

- patient first name
- patient last name
- patient date of birth
- any patient identifiers
- encounter identifier (if applicable)
- encounter department/location (if applicable)
- any unique record identifiers for the triggering event (e.g., order, result, medication admin ID)
- relevant provider IDs and names (for orders)
- procedure code (for orders)

</details>