Vital Signs Element Documentation

Overview

Vital Signs elements represent measured physiological parameters like blood pressure, heart rate, temperature, and other clinical measurements taken during patient care.

Function

builder.add_vital_finding(
    code: CodeInput,
    value: Optional[Union[str, float]] = None,
    unit: Optional[str] = None,
    date: Optional[DateTimeInput] = None,
    interpretation: Optional[Union[Interpretation, str]] = None,
    notes: Optional[str] = None,
    id: Optional[str] = None,
) -> Observation

Parameters

Required Parameters

• code: The vital sign type or measurement name

Optional Parameters

• value: The measured value (numeric or string)
• unit: Unit of measurement (e.g., “mmHg”, “bpm”, “°C”)
• date: When the measurement was taken
• interpretation: Clinical interpretation of the result
• notes: Additional notes about the measurement
• id: Custom resource ID

Basic Usage

Simple Vital Sign (Preferred with CodeableConcept)

from fhir_sdk import FHIRDocumentBuilder
from fhir_sdk.types import create_codeable_concept

builder = FHIRDocumentBuilder()
builder.add_patient(name="John Doe", age=30)
builder.add_encounter()

# Add blood pressure measurement
vital = builder.add_vital_finding(
    code=create_codeable_concept(
        text="Blood Pressure",
        code="85354007",
        system="http://snomed.info/sct",
        display="Blood pressure"
    ),
    value="120/80",
    unit="mmHg"
)

Using String (Alternative)

vital = builder.add_vital_finding(
    code="Blood Pressure",
    value="120/80",
    unit="mmHg"
)

Numeric Value with Interpretation

from fhir_sdk import Interpretation

vital = builder.add_vital_finding(
    code=create_codeable_concept(
        text="Heart Rate",
        code="364075005",
        system="http://snomed.info/sct"
    ),
    value=72,
    unit="bpm",
    interpretation=Interpretation.NORMAL
)

Interpretation Options

from fhir_sdk import Interpretation

# Using enum (preferred)
vital = builder.add_vital_finding(
    code="Temperature",
    value=38.5,
    unit="°C",
    interpretation=Interpretation.HIGH
)

# Using string (alternative)
vital = builder.add_vital_finding(
    code="Temperature",
    value=36.7,
    unit="°C",
    interpretation="normal"
)

Available interpretations:

• Interpretation.NORMAL or "normal"
• Interpretation.HIGH or "high"
• Interpretation.LOW or "low"
• Interpretation.ABNORMAL or "abnormal"

Common Vital Signs with LOINC Codes

Blood Pressure

vital = builder.add_vital_finding(
    code=create_codeable_concept(
        text="Blood Pressure",
        code="85354007",
        system="http://snomed.info/sct",
        display="Blood pressure"
    ),
    value="120/80",
    unit="mmHg",
    interpretation=Interpretation.NORMAL
)

Heart Rate

vital = builder.add_vital_finding(
    code=create_codeable_concept(
        text="Heart Rate",
        code="8867-4",
        system="http://loinc.org",
        display="Heart rate"
    ),
    value=75,
    unit="bpm"
)

Body Temperature

vital = builder.add_vital_finding(
    code=create_codeable_concept(
        text="Body Temperature",
        code="8310-5",
        system="http://loinc.org",
        display="Body temperature"
    ),
    value=98.6,
    unit="°F"
)

Respiratory Rate

vital = builder.add_vital_finding(
    code=create_codeable_concept(
        text="Respiratory Rate",
        code="9279-1",
        system="http://loinc.org"
    ),
    value=16,
    unit="breaths/min"
)

Body Weight

vital = builder.add_vital_finding(
    code=create_codeable_concept(
        text="Body Weight",
        code="29463-7",
        system="http://loinc.org"
    ),
    value=70,
    unit="kg"
)

Height

vital = builder.add_vital_finding(
    code=create_codeable_concept(
        text="Body Height",
        code="8302-2",
        system="http://loinc.org"
    ),
    value=175,
    unit="cm"
)

Value Types and Units

Numeric Values

# Integer values
vital = builder.add_vital_finding(code="Heart Rate", value=72, unit="bpm")

# Decimal values
vital = builder.add_vital_finding(code="Temperature", value=98.6, unit="°F")

String Values

# Compound measurements
vital = builder.add_vital_finding(code="Blood Pressure", value="120/80", unit="mmHg")

# Qualitative results
vital = builder.add_vital_finding(code="Pain Scale", value="5/10")

Time-stamped Measurements

from datetime import datetime

vital = builder.add_vital_finding(
    code="Blood Pressure",
    value="130/85",
    unit="mmHg",
    date=datetime.now(),
    notes="Taken after 5 minutes rest"
)

Measurements Without Values

# For measurements that couldn't be taken
vital = builder.add_vital_finding(
    code="Weight",
    notes="Unable to obtain - patient unable to stand"
)

Common Units

• Blood Pressure: “mmHg”
• Heart Rate: “bpm” (beats per minute)
• Temperature: “°C”, “°F”
• Weight: “kg”, “lb”
• Height: “cm”, “in”
• Respiratory Rate: “breaths/min”
• Oxygen Saturation: ”%“

Best Practices

1. Use create_codeable_concept with LOINC codes for vital signs when available
2. Include appropriate units for all numeric measurements
3. Add interpretation for values outside normal ranges
4. Record measurement time for trend analysis
5. Include notes for unusual circumstances or measurement conditions
6. Use consistent units within your application
7. Record “unable to obtain” measurements with explanatory notes

Notes

• Vital signs are categorized as “vital-signs” observations
• Values can be numeric (with units) or string (for complex measurements)
• Interpretation helps identify abnormal values quickly
• Multiple measurements can track trends over time
• Date/time stamps are important for monitoring changes