# Cardiac Anesthesia Risk Evaluation (CARE)

CARE

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/care`
HTML: https://magentlab.com/docs/care
Markdown: https://magentlab.com/docs/care.md

Not a medical device. Not a diagnosis, dose, or listing recommendation.

## What it computes

Return the caller-assigned Cardiac Anesthesia Risk Evaluation (CARE) class 1-5 with optional emergency suffix E for classes 3-5 and Dupuis 2001 Table 4 mortality and morbidity percents.

## When to use

When an agent already has a Dupuis 2001 CARE class 1-5 and whether the case is an emergency requiring immediate surgery, and needs the canonical label (e.g. 1 or 3E). magent does not examine the patient or assign the class. Not an anesthetic plan and not Gupta MICA.

## When not to use

- Not a medical device. Not an anesthetic plan or surgical booking.
- The caller assigns CARE class 1-5 and the emergency flag. magent does not examine the patient. Footnote definitions of controlled or uncontrolled medical problems and complex surgery in Dupuis 2001 Table 1 are not extra scored items.
- Emergency E applies only to classes 3-5 (Dupuis 2001). Class 1 or 2 with emergency true is rejected. Unstable conditions needing surgery within 24 h but not immediately are uncontrolled medical problems, not E.
- Mortality and morbidity percents are Dupuis 2001 Table 4 logistic-regression probabilities from the Ottawa Heart Institute reference population (n=2000), not individual prognosis. Not Parsonnet, EuroSCORE, or Gupta MICA.

## Formula

```
Caller-assigned CARE class 1-5; append E when emergency is true for classes 3-5 only (Dupuis 2001). Emergency never applies to CARE 1 or 2.
```

## Citation

[The cardiac anesthesia risk evaluation score: a clinically useful predictor of mortality and morbidity after cardiac surgery](https://doi.org/10.1097/00000542-200102000-00006)
Dupuis JY, Wang F, Nathan H, Lam M, Grimes S, Bourke M
Anesthesiology. 2001;94(2):194-204
DOI: [10.1097/00000542-200102000-00006](https://doi.org/10.1097/00000542-200102000-00006)

## Worked example

### CARE 1 not emergency

Given: `care_class=1, emergency=false`

1. care_class 1, emergency false → care_label 1; stable cardiac disease, no other medical problem, noncomplex surgery


### CARE 3E emergency

Given: `care_class=3, emergency=true`

1. care_class 3, emergency true → care_label 3E; uncontrolled medical problem or complex surgery with E suffix


## Also searched as

- CARE score
- cardiac anesthesia risk evaluation
- Dupuis CARE
- CARE class
- CARE 3E 4E 5E
- cardiac surgery risk class
- CARE classification
- Ottawa CARE score

## Parameters

- `care_class` (integer, required): Dupuis 2001 CARE class 1-5 as assigned by the caller (1 stable cardiac disease, no other medical problem, noncomplex surgery; 2 stable cardiac disease, one or more controlled medical problems, noncomplex surgery; 3 any uncontrolled medical problem or complex surgery; 4 uncontrolled medical problem and complex surgery; 5 chronic or advanced cardiac disease, surgery as last hope). magent does not examine the patient.
- `emergency` (boolean, required): true appends E for emergency surgery as soon as the diagnosis is made and an operating room is available (Dupuis 2001). Required. E applies only to classes 3-5 (labels 3E, 4E, 5E). Class 1 or 2 with emergency true is rejected. Unstable conditions needing surgery within 24 h but not immediately are uncontrolled medical problems, not E. magent does not examine the patient.

## Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

Method: `POST /api/calc/care`
Max items: 25
Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic)
Status: PREVIEW

- 1 to 25 items. Each item uses the same keys as the GET query parameters.
- POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
- The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
- HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
- Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
- x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request:

```json
{
  "items": [
    {
      "care_class": "1",
      "emergency": "false"
    },
    {
      "care_class": "1",
      "emergency": "false"
    }
  ]
}
```

Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/care

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/care",
  "items": [
    {
      "description": "Patient with stable cardiac disease and no other medical problem. A noncomplex surgery is undertaken.",
      "emergency": false,
      "components": [
        {
          "value": 1,
          "factor": "care_class",
          "met": true
        },
        {
          "factor": "emergency",
          "met": false
        }
      ],
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Dupuis JY, Wang F, Nathan H, Lam M, Grimes S, Bourke M",
        "doi": "10.1097/00000542-200102000-00006",
        "id": "dupuis-2001",
        "pmid": "11176081",
        "source": "Anesthesiology. 2001;94(2):194-204",
        "title": "The cardiac anesthesia risk evaluation score: a clinically useful predictor of mortality and morbidity after cardiac surgery"
      },
      "formula": "care",
      "formula_expression": "Caller-assigned CARE class 1-5; append E when emergency is true for classes 3-5 only (Dupuis 2001). Emergency never applies to CARE 1 or 2.",
      "care_class": 1,
      "care_label": "1",
      "morbidity_percent": 5.4,
      "mortality_percent": 0.5
    },
    {
      "description": "Patient with stable cardiac disease and no other medical problem. A noncomplex surgery is undertaken.",
      "emergency": false,
      "components": [
        {
          "value": 1,
          "factor": "care_class",
          "met": true
        },
        {
          "factor": "emergency",
          "met": false
        }
      ],
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Dupuis JY, Wang F, Nathan H, Lam M, Grimes S, Bourke M",
        "doi": "10.1097/00000542-200102000-00006",
        "id": "dupuis-2001",
        "pmid": "11176081",
        "source": "Anesthesiology. 2001;94(2):194-204",
        "title": "The cardiac anesthesia risk evaluation score: a clinically useful predictor of mortality and morbidity after cardiac surgery"
      },
      "formula": "care",
      "formula_expression": "Caller-assigned CARE class 1-5; append E when emergency is true for classes 3-5 only (Dupuis 2001). Emergency never applies to CARE 1 or 2.",
      "care_class": 1,
      "care_label": "1",
      "morbidity_percent": 5.4,
      "mortality_percent": 0.5
    }
  ]
}
```

## Response fields

- `formula` (string): care
- `formula_expression` (string): Published Dupuis 2001 class-plus-E rule
- `care_class` (integer): Caller-assigned class 1-5
- `emergency` (boolean): true when the caller assigns the emergency suffix E (classes 3-5 only)
- `care_label` (string): Class as a string; E is appended when emergency is true (e.g. 1 or 3E)
- `description` (string): Dupuis 2001 Table 1 wording for that class
- `mortality_percent` (number): Dupuis 2001 Table 4 in-hospital mortality percent (Ottawa reference population logistic regression)
- `morbidity_percent` (number): Dupuis 2001 Table 4 morbidity percent (Ottawa reference population logistic regression)
- `components` (array): care_class and emergency criterion rows
- `citation` (object): Dupuis 2001
- `disclaimer` (string): Not a medical device

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "description": "Patient with stable cardiac disease and no other medical problem. A noncomplex surgery is undertaken.",
  "emergency": false,
  "components": [
    {
      "value": 1,
      "factor": "care_class",
      "met": true
    },
    {
      "factor": "emergency",
      "met": false
    }
  ],
  "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "citation": {
    "authors": "Dupuis JY, Wang F, Nathan H, Lam M, Grimes S, Bourke M",
    "doi": "10.1097/00000542-200102000-00006",
    "id": "dupuis-2001",
    "pmid": "11176081",
    "source": "Anesthesiology. 2001;94(2):194-204",
    "title": "The cardiac anesthesia risk evaluation score: a clinically useful predictor of mortality and morbidity after cardiac surgery"
  },
  "formula": "care",
  "formula_expression": "Caller-assigned CARE class 1-5; append E when emergency is true for classes 3-5 only (Dupuis 2001). Emergency never applies to CARE 1 or 2.",
  "care_class": 1,
  "care_label": "1",
  "morbidity_percent": 5.4,
  "mortality_percent": 0.5
}
```

## Errors

- HTTP 400 `invalid_care`: CARE class must be a caller-assigned integer 1-5; emergency E applies only to classes 3-5 (Dupuis 2001). Returned before settlement; you are not charged.
- HTTP 400 `invalid_flag`: boolean clinical flags must be true or false Returned before settlement; you are not charged.
- HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
- HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
- HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged.

Shared HTTP 402 and 503: https://magentlab.com/docs/payments

## Related tools

- [ASA-PS](https://magentlab.com/docs/asa-physical-status) — Return the caller-assigned ASA Physical Status class 1-6 with optional emergency suffix E and the published class definition (ASA 2014, last amended 2020).
- [Gupta MICA](https://magentlab.com/docs/gupta-mica) — Compute the Gupta 2011 Table 2 logistic probability of 30-day myocardial infarction or cardiac arrest after surgery from age, ASA class, functional status, creatinine category, and surgery type.

## Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s.

- GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall).
- HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote.
- Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering.
- Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional.
- Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402.

- offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront.
- offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization.

- not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search.

Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers).

Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments

Stdio MCP (one process per host): https://magentlab.com/docs/mcp

## Guarantees

- HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
- exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
- HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
- Execution is timeout-bounded and concurrency-capped.
- Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.