Emergency · LIVE

FAST windows (Scalea)

Apply Scalea 1999 FAST four Ps and return positive when any caller-assigned perihepatic, perisplenic, pelvic, or pericardial window has free fluid.

LIVE $0.005 USDC GET /api/calc/fast

Markdown: /docs/fast.md · Canonical: https://magentlab.com/docs/fast

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

What it computes

Apply Scalea 1999 FAST four Ps and return positive when any caller-assigned perihepatic, perisplenic, pelvic, or pericardial window has free fluid.

When to use

When an agent already has caller-assigned perihepatic (Morison), perisplenic, pelvic, and pericardial window flags and needs the published FAST positive or negative result. magent does not scan.

When not to use

• Not a medical device. magent does not perform or interpret ultrasound.
• Not a laparotomy, thoracotomy, or pericardial-window operative order.
• Windows are caller-assigned. magent does not decide whether a view shows free fluid or pericardial fluid.
• Scalea 1999 four Ps only (pericardial, perihepatic, perisplenic, pelvic). Not eFAST pleural views; the consensus left pleural extension as not well characterized.
• Not Huang or McKenney hemoperitoneum scoring. Not organ-specific injury grading.

Formula

positive iff perihepatic or perisplenic or pelvic or pericardial (Scalea 1999 four Ps: pericardial, perihepatic, perisplenic, pelvic). Each flag is caller-assigned free intraperitoneal fluid (perihepatic/Morison, perisplenic, pelvic) or pericardial fluid. Absence of all four is negative. Sequence is not required. Not pleural/eFAST views. Not Huang or McKenney scoring. Not a laparotomy order

Citation

Title

Focused Assessment with Sonography for Trauma (FAST): results from an international consensus conference

Authors

Scalea TM, Rodriguez A, Chiu WC, Brenneman FD, Fallon WF Jr, Kato K, McKenney MG, Nerlich ML, Ochsner MG, Yoshii H

Source

J Trauma. 1999;46(3):466-472

DOI

10.1097/00005373-199903000-00022

Worked example

Also searched as

• FAST
• Focused Assessment with Sonography for Trauma
• Scalea FAST consensus
• FAST four Ps
• perihepatic Morison FAST
• perisplenic FAST
• FAST pericardial window
• trauma ultrasound windows

Try

Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.

/api/calc/fast?perihepatic=false&perisplenic=false&pelvic=false&pericardial=false

Full URL: https://api.magentlab.com/api/calc/fast?perihepatic=false&perisplenic=false&pelvic=false&pericardial=false

Call

Expect HTTP 402 until you retry with PAYMENT-SIGNATURE. Incomplete query params return HTTP 400 before any quote or charge.

curl -i -H "Accept: application/json" "https://api.magentlab.com/api/calc/fast?perihepatic=false&perisplenic=false&pelvic=false&pericardial=false"

Parameters

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.

POST /api/calc/fast Max 25 unit_amount + extra_item_amount * (n - 1) extra $0.002 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 (fixture)

{
  "items": [
    {
      "pelvic": "false",
      "pericardial": "false",
      "perihepatic": "false",
      "perisplenic": "false"
    },
    {
      "pelvic": "false",
      "pericardial": "false",
      "perihepatic": "false",
      "perisplenic": "false"
    }
  ]
}

Open bulk paywall →

Opens a two-item fixture on the API host. Unpaid browsers get the same MetaMask paywall as GET; Pay retries POST with those items.

Example 200 (fixture)

{
  "count": 2,
  "path": "/api/calc/fast",
  "items": [
    {
      "positive": false,
      "components": [
        {
          "factor": "perihepatic",
          "met": false
        },
        {
          "factor": "perisplenic",
          "met": false
        },
        {
          "factor": "pelvic",
          "met": false
        },
        {
          "factor": "pericardial",
          "met": false
        },
        {
          "factor": "positive",
          "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": "Scalea TM, Rodriguez A, Chiu WC, Brenneman FD, Fallon WF Jr, Kato K, McKenney MG, Nerlich ML, Ochsner MG, Yoshii H",
        "doi": "10.1097/00005373-199903000-00022",
        "id": "scalea-1999",
        "pmid": "10088853",
        "source": "J Trauma. 1999;46(3):466-472",
        "title": "Focused Assessment with Sonography for Trauma (FAST): results from an international consensus conference"
      },
      "formula": "fast",
      "formula_expression": "positive iff perihepatic or perisplenic or pelvic or pericardial (Scalea 1999 four Ps: pericardial, perihepatic, perisplenic, pelvic). Each flag is caller-assigned free intraperitoneal fluid (perihepatic/Morison, perisplenic, pelvic) or pericardial fluid. Absence of all four is negative. Sequence is not required. Not pleural/eFAST views. Not Huang or McKenney scoring. Not a laparotomy order",
      "pelvic": false,
      "pericardial": false,
      "perihepatic": false,
      "perisplenic": false
    },
    {
      "positive": false,
      "components": [
        {
          "factor": "perihepatic",
          "met": false
        },
        {
          "factor": "perisplenic",
          "met": false
        },
        {
          "factor": "pelvic",
          "met": false
        },
        {
          "factor": "pericardial",
          "met": false
        },
        {
          "factor": "positive",
          "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": "Scalea TM, Rodriguez A, Chiu WC, Brenneman FD, Fallon WF Jr, Kato K, McKenney MG, Nerlich ML, Ochsner MG, Yoshii H",
        "doi": "10.1097/00005373-199903000-00022",
        "id": "scalea-1999",
        "pmid": "10088853",
        "source": "J Trauma. 1999;46(3):466-472",
        "title": "Focused Assessment with Sonography for Trauma (FAST): results from an international consensus conference"
      },
      "formula": "fast",
      "formula_expression": "positive iff perihepatic or perisplenic or pelvic or pericardial (Scalea 1999 four Ps: pericardial, perihepatic, perisplenic, pelvic). Each flag is caller-assigned free intraperitoneal fluid (perihepatic/Morison, perisplenic, pelvic) or pericardial fluid. Absence of all four is negative. Sequence is not required. Not pleural/eFAST views. Not Huang or McKenney scoring. Not a laparotomy order",
      "pelvic": false,
      "pericardial": false,
      "perihepatic": false,
      "perisplenic": false
    }
  ]
}

Response

Example JSON

Machine form of the same example. Frozen fixture. Not a live lookup.

{
  "positive": false,
  "components": [
    {
      "factor": "perihepatic",
      "met": false
    },
    {
      "factor": "perisplenic",
      "met": false
    },
    {
      "factor": "pelvic",
      "met": false
    },
    {
      "factor": "pericardial",
      "met": false
    },
    {
      "factor": "positive",
      "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": "Scalea TM, Rodriguez A, Chiu WC, Brenneman FD, Fallon WF Jr, Kato K, McKenney MG, Nerlich ML, Ochsner MG, Yoshii H",
    "doi": "10.1097/00005373-199903000-00022",
    "id": "scalea-1999",
    "pmid": "10088853",
    "source": "J Trauma. 1999;46(3):466-472",
    "title": "Focused Assessment with Sonography for Trauma (FAST): results from an international consensus conference"
  },
  "formula": "fast",
  "formula_expression": "positive iff perihepatic or perisplenic or pelvic or pericardial (Scalea 1999 four Ps: pericardial, perihepatic, perisplenic, pelvic). Each flag is caller-assigned free intraperitoneal fluid (perihepatic/Morison, perisplenic, pelvic) or pericardial fluid. Absence of all four is negative. Sequence is not required. Not pleural/eFAST views. Not Huang or McKenney scoring. Not a laparotomy order",
  "pelvic": false,
  "pericardial": false,
  "perihepatic": false,
  "perisplenic": false
}

Client errors (HTTP 400)

Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.

Related tools

• ABC score — Sum the four Nunez 2009 ABC (assessment of blood consumption) arrival factors and return score_ge_2 at the published ≥2 cutoff.

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. Unpaid valid requests return HTTP 402 with a base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote: retry the same PAYMENT-SIGNATURE. Full handshake and shared payment errors: Payments. Stdio MCP: /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.