Emergency · LIVE

New Orleans Head CT Rule

Apply the Haydel 2000 New Orleans Head CT Rule and return whether CT is indicated from age and six caller-assigned findings after minor head injury.

LIVE $0.005 USDC GET /api/calc/new_orleans_head

Markdown: /docs/new-orleans-head.md · Canonical: https://magentlab.com/docs/new-orleans-head

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

What it computes

Apply the Haydel 2000 New Orleans Head CT Rule and return whether CT is indicated from age and six caller-assigned findings after minor head injury.

When to use

When an agent has caller-assigned findings after minor head injury in an adult with GCS 15 as published and needs the New Orleans (Charity) Head CT Rule, not the Canadian CT Head Rule and not PECARN.

When not to use

• Not a diagnosis of brain injury. magent does not examine the patient.
• The published rule is GCS 15 minor head injury in adults. magent does not take GCS; the caller assigns the clinical flags.
• This tool is the Haydel 2000 New Orleans / Charity Head CT Rule only. It is not the Canadian CT Head Rule, not PECARN, and not a pediatric head-CT rule.

Formula

ct indicated if any of headache, vomiting, age > 60, drug_or_alcohol_intoxication, short_term_memory_deficit, trauma_above_clavicles, or seizure

Citation

Title

Indications for computed tomography in patients with minor head injury

Authors

Haydel MJ, Preston CA, Mills TJ, Luber S, Blaudeau E, DeBlieux PM

Source

N Engl J Med. 2000;343(2):100-105

DOI

10.1056/NEJM200007133430204

Worked example

Also searched as

• New Orleans Head CT Rule
• New Orleans Criteria
• Charity Head CT Rule
• Haydel head CT
• Haydel 2000
• NOC head CT
• New Orleans Criteria for CT
• Charity Hospital head CT rule

Try

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

/api/calc/new_orleans_head?age=40&headache=false&vomiting=false&drug_or_alcohol_intoxication=false&short_term_memory_deficit=false&trauma_above_clavicles=false&seizure=false

Full URL: https://api.magentlab.com/api/calc/new_orleans_head?age=40&headache=false&vomiting=false&drug_or_alcohol_intoxication=false&short_term_memory_deficit=false&trauma_above_clavicles=false&seizure=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/new_orleans_head?age=40&headache=false&vomiting=false&drug_or_alcohol_intoxication=false&short_term_memory_deficit=false&trauma_above_clavicles=false&seizure=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/new_orleans_head 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": [
    {
      "age": "40",
      "drug_or_alcohol_intoxication": "false",
      "headache": "false",
      "seizure": "false",
      "short_term_memory_deficit": "false",
      "trauma_above_clavicles": "false",
      "vomiting": "false"
    },
    {
      "age": "40",
      "drug_or_alcohol_intoxication": "false",
      "headache": "false",
      "seizure": "false",
      "short_term_memory_deficit": "false",
      "trauma_above_clavicles": "false",
      "vomiting": "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/new_orleans_head",
  "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": "Haydel MJ, Preston CA, Mills TJ, Luber S, Blaudeau E, DeBlieux PM",
        "doi": "10.1056/NEJM200007133430204",
        "id": "haydel-2000",
        "source": "N Engl J Med. 2000;343(2):100-105",
        "title": "Indications for computed tomography in patients with minor head injury"
      },
      "formula": "new_orleans_head",
      "formula_expression": "ct indicated if any of headache, vomiting, age > 60, drug_or_alcohol_intoxication, short_term_memory_deficit, trauma_above_clavicles, or seizure",
      "age_years": 40,
      "criteria": [
        {
          "factor": "headache",
          "met": false
        },
        {
          "factor": "vomiting",
          "met": false
        },
        {
          "value": 40,
          "factor": "age_gt_60",
          "met": false
        },
        {
          "factor": "drug_or_alcohol_intoxication",
          "met": false
        },
        {
          "factor": "short_term_memory_deficit",
          "met": false
        },
        {
          "factor": "trauma_above_clavicles",
          "met": false
        },
        {
          "factor": "seizure",
          "met": false
        }
      ],
      "ct_indicated": 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": "Haydel MJ, Preston CA, Mills TJ, Luber S, Blaudeau E, DeBlieux PM",
        "doi": "10.1056/NEJM200007133430204",
        "id": "haydel-2000",
        "source": "N Engl J Med. 2000;343(2):100-105",
        "title": "Indications for computed tomography in patients with minor head injury"
      },
      "formula": "new_orleans_head",
      "formula_expression": "ct indicated if any of headache, vomiting, age > 60, drug_or_alcohol_intoxication, short_term_memory_deficit, trauma_above_clavicles, or seizure",
      "age_years": 40,
      "criteria": [
        {
          "factor": "headache",
          "met": false
        },
        {
          "factor": "vomiting",
          "met": false
        },
        {
          "value": 40,
          "factor": "age_gt_60",
          "met": false
        },
        {
          "factor": "drug_or_alcohol_intoxication",
          "met": false
        },
        {
          "factor": "short_term_memory_deficit",
          "met": false
        },
        {
          "factor": "trauma_above_clavicles",
          "met": false
        },
        {
          "factor": "seizure",
          "met": false
        }
      ],
      "ct_indicated": false
    }
  ]
}

Response

Example JSON

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

{
  "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": "Haydel MJ, Preston CA, Mills TJ, Luber S, Blaudeau E, DeBlieux PM",
    "doi": "10.1056/NEJM200007133430204",
    "id": "haydel-2000",
    "source": "N Engl J Med. 2000;343(2):100-105",
    "title": "Indications for computed tomography in patients with minor head injury"
  },
  "formula": "new_orleans_head",
  "formula_expression": "ct indicated if any of headache, vomiting, age > 60, drug_or_alcohol_intoxication, short_term_memory_deficit, trauma_above_clavicles, or seizure",
  "age_years": 40,
  "criteria": [
    {
      "factor": "headache",
      "met": false
    },
    {
      "factor": "vomiting",
      "met": false
    },
    {
      "value": 40,
      "factor": "age_gt_60",
      "met": false
    },
    {
      "factor": "drug_or_alcohol_intoxication",
      "met": false
    },
    {
      "factor": "short_term_memory_deficit",
      "met": false
    },
    {
      "factor": "trauma_above_clavicles",
      "met": false
    },
    {
      "factor": "seizure",
      "met": false
    }
  ],
  "ct_indicated": false
}

Client errors (HTTP 400)

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

Related tools

• Canadian CT Head Rule — Apply the Stiell 2001 Canadian CT Head Rule and return whether CT is indicated from caller-assigned high-risk and medium-risk findings after minor blunt head injury.
• NEXUS C-spine — Apply the Hoffman 2000 NEXUS C-spine rule and return whether the five low-risk criteria all hold (imaging not indicated by this rule).

Payment

Required query parameters must be present and valid. 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

• Invalid query parameters return HTTP 400 before settlement. You are not charged.
• Settlement finishes before the tool executes (paymentFlow upfront). 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.