Source: https://guthlabs.ai/docs/instruments/cardiac-output-related-hemodynamics/implementation/

instrument implementation / implementation-contract

# Cardiac Output & Related Hemodynamics implementation

A source-bound implementation contract for Cardiac Output & Related Hemodynamics; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t4-194

**Effect**: Computation or source lookup only

## Input and validation requirements

BSA=0 makes CI undefined by division by zero, so the instrument must reject that input. The specification also leaves SV units implicit; interpreting SV as mL/beat requires an unstated conversion to produce CO in L/min.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "HR_bpm": 70,
    "SV_mL_per_beat": 70,
    "BSA_m2": 1.8,
    "SBP_mmHg": 120,
    "DBP_mmHg": 80
  },
  "expected_outputs": {
    "CO_L_per_min": 4.9,
    "CI_L_per_min_per_m2": 2.7222222222,
    "MAP_mmHg": 93.3333333333
  },
  "working": "CO=(70 beats/min×70 mL/beat)÷1000=4900 mL/min÷1000=4.9 L/min. CI=4.9÷1.8=2.7222222222 L/min/m². MAP=80+1/3×(120−80)=80+40/3=93.3333333333 mmHg."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/cardiac-output-related-hemodynamics/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/cardiac-output-related-hemodynamics/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/cardiac-output-related-hemodynamics/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche4/tranche4-results.json`