# CAM-ICU

CAM-ICU

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

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

## What it computes

Apply the Ely 2001 CAM-ICU algorithm and return whether delirium is present from four caller-assigned features.

## When to use

When an agent already has the four CAM-ICU features assigned as in Ely 2001 (mechanically ventilated adults in the validation paper) and needs the published delirium present/absent result. magent does not administer RASS or the attention screening exam.

## When not to use

- Not a medical device.
- Not a diagnosis. magent does not diagnose delirium.
- The caller assigns the four CAM-ICU features as already determined. magent does not observe the patient.
- magent does not administer RASS and does not run the attention screening exam.

## Formula

```
delirium present iff Feature 1 AND Feature 2 AND (Feature 3 OR Feature 4)
```

## Citation

[Delirium in mechanically ventilated patients: validity and reliability of the confusion assessment method for the intensive care unit (CAM-ICU)](https://doi.org/10.1001/jama.286.21.2703)
Ely EW, Inouye SK, Bernard GR, et al.
JAMA. 2001;286(21):2703-2710
DOI: [10.1001/jama.286.21.2703](https://doi.org/10.1001/jama.286.21.2703)

## Worked example

### All four features absent

Given: `acute_onset_or_fluctuation=false, altered_level_of_consciousness=false, disorganized_thinking=false, inattention=false`

1. All four caller-assigned CAM-ICU features are false
2. Feature 1 and Feature 2 are absent; delirium is not present


### Features 1, 2, and 4 present

Given: `acute_onset_or_fluctuation=true, altered_level_of_consciousness=true, disorganized_thinking=false, inattention=true`

1. Feature 1 and Feature 2 hold; Feature 4 holds; Feature 3 is absent
2. Delirium is present because Feature 3 or Feature 4 holds


## Also searched as

- CAM-ICU
- Confusion Assessment Method ICU
- Ely CAM-ICU
- ICU delirium CAM
- CAM for the intensive care unit
- Confusion Assessment Method for the ICU
- Ely 2001 CAM-ICU

## Parameters

- `acute_onset_or_fluctuation` (boolean, required): Feature 1: acute onset of mental status change or fluctuating course. true or false as assigned by the caller. magent does not observe the patient or judge fluctuation.
- `inattention` (boolean, required): Feature 2: inattention. true or false as assigned by the caller. magent does not run the attention screening exam.
- `disorganized_thinking` (boolean, required): Feature 3: disorganized thinking. true or false as assigned by the caller. magent does not administer the thinking questions.
- `altered_level_of_consciousness` (boolean, required): Feature 4: altered level of consciousness. true or false as assigned by the caller. magent does not administer RASS.

## 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/cam_icu`
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": [
    {
      "acute_onset_or_fluctuation": "false",
      "altered_level_of_consciousness": "false",
      "disorganized_thinking": "false",
      "inattention": "false"
    },
    {
      "acute_onset_or_fluctuation": "false",
      "altered_level_of_consciousness": "false",
      "disorganized_thinking": "false",
      "inattention": "false"
    }
  ]
}
```

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

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/cam_icu",
  "items": [
    {
      "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": "Ely EW, Inouye SK, Bernard GR, et al.",
        "doi": "10.1001/jama.286.21.2703",
        "id": "ely-2001",
        "pmid": "11730446",
        "source": "JAMA. 2001;286(21):2703-2710",
        "title": "Delirium in mechanically ventilated patients: validity and reliability of the confusion assessment method for the intensive care unit (CAM-ICU)"
      },
      "formula": "cam_icu",
      "formula_expression": "delirium present iff Feature 1 AND Feature 2 AND (Feature 3 OR Feature 4)",
      "criteria": [
        {
          "factor": "acute_onset_or_fluctuation",
          "met": false
        },
        {
          "factor": "inattention",
          "met": false
        },
        {
          "factor": "disorganized_thinking",
          "met": false
        },
        {
          "factor": "altered_level_of_consciousness",
          "met": false
        }
      ],
      "delirium_present": 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": "Ely EW, Inouye SK, Bernard GR, et al.",
        "doi": "10.1001/jama.286.21.2703",
        "id": "ely-2001",
        "pmid": "11730446",
        "source": "JAMA. 2001;286(21):2703-2710",
        "title": "Delirium in mechanically ventilated patients: validity and reliability of the confusion assessment method for the intensive care unit (CAM-ICU)"
      },
      "formula": "cam_icu",
      "formula_expression": "delirium present iff Feature 1 AND Feature 2 AND (Feature 3 OR Feature 4)",
      "criteria": [
        {
          "factor": "acute_onset_or_fluctuation",
          "met": false
        },
        {
          "factor": "inattention",
          "met": false
        },
        {
          "factor": "disorganized_thinking",
          "met": false
        },
        {
          "factor": "altered_level_of_consciousness",
          "met": false
        }
      ],
      "delirium_present": false
    }
  ]
}
```

## Response fields

- `formula` (string): cam_icu
- `formula_expression` (string): Ely 2001: Feature 1 AND Feature 2 AND (Feature 3 OR Feature 4)
- `delirium_present` (boolean): true only when Feature 1 and Feature 2 hold and Feature 3 or Feature 4 also holds. Not a diagnosis.
- `criteria` (array): Per-feature rows with factor and met; met is true when that CAM-ICU feature is present
- `citation` (object): Ely 2001 JAMA citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "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": "Ely EW, Inouye SK, Bernard GR, et al.",
    "doi": "10.1001/jama.286.21.2703",
    "id": "ely-2001",
    "pmid": "11730446",
    "source": "JAMA. 2001;286(21):2703-2710",
    "title": "Delirium in mechanically ventilated patients: validity and reliability of the confusion assessment method for the intensive care unit (CAM-ICU)"
  },
  "formula": "cam_icu",
  "formula_expression": "delirium present iff Feature 1 AND Feature 2 AND (Feature 3 OR Feature 4)",
  "criteria": [
    {
      "factor": "acute_onset_or_fluctuation",
      "met": false
    },
    {
      "factor": "inattention",
      "met": false
    },
    {
      "factor": "disorganized_thinking",
      "met": false
    },
    {
      "factor": "altered_level_of_consciousness",
      "met": false
    }
  ],
  "delirium_present": false
}
```

## Errors

- 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

- [Glasgow Coma Scale](https://magentlab.com/docs/gcs) — Compute the Glasgow Coma Scale as the sum of caller-assigned eye, verbal, and motor integers. The 1974 or 1976 edition is required.
- [FOUR score](https://magentlab.com/docs/four-score) — Compute the FOUR score as the sum of caller-assigned eye, motor, brainstem, and respiration integers 0-4.

## 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.
- 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.