Bastion classification of lower-limb IED injury

Bastion

Return the caller-assigned Bastion class 1-5 (most proximal extent of the lower-limb blast injury), Jacobs 2014 associated-injury flags, the published class description, and tourniquet_effective (true for class 1-3, false for class 4-5).

LIVE $0.005 USDC GET /api/calc/bastion

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

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

What it computes

When to use

When an agent already has the most proximal extent of a lower-limb blast injury as class 1-5 and the associated-injury flags, and needs the published Jacobs 2014 class description and whether a tourniquet is effective from that class. magent does not examine the casualty. Not MESS and not ISS.

When not to use

Not a medical device. magent does not examine the casualty. The caller assigns Bastion class 1-5 as the most proximal extent of the lower-limb blast injury.
Not MESS (Johansen 1990). Not ISS body-region AIS (Baker 1974). Not a treatment, amputation, or vascular-control protocol.
Jacobs 2014 was not designed for mortality or transfusion outcomes; magent does not invent those rates. Associated injuries are returned as the published flags, not as a composed letter suffix.

Formula

Caller-assigned Bastion class 1-5 is the most proximal extent of the lower-limb blast injury; associated flags are segmental, intraperitoneal_abdomen, genital_perineal, pelvic_ring, and upper_limb; tourniquet_effective is true for class 1-3 and false for class 4-5 (Jacobs 2014)

Citation

Title: Lower limb injuries caused by improvised explosive devices: proposed 'Bastion classification' and prospective validation
Authors: Jacobs N, Rourke K, Rutherford J, Hicks A, Smith SR, Templeton P, Adams SA, Jansen JO
Source: Injury. 2014;45(9):1422-1428
DOI: 10.1016/j.injury.2012.05.001

Worked example

Class 1 foot, no associated injuries

Given: bastion_class=1genital_perineal=falseintraperitoneal_abdomen=falsepelvic_ring=falsesegmental=falseupper_limb=false

bastion_class 1, all associated-injury flags false
description: injury confined to the foot; tourniquet_effective true (class 1-3)

Class 4 proximal thigh, no associated injuries

Given: bastion_class=4genital_perineal=falseintraperitoneal_abdomen=falsepelvic_ring=falsesegmental=falseupper_limb=false

bastion_class 4, all associated-injury flags false
description: proximal thigh injury, preventing effective tourniquet application; tourniquet_effective false (class 4-5)

Also searched as

Bastion classification
Bastion class
IED lower limb injury
Jacobs 2014 Bastion
lower-limb blast injury class
tourniquet Bastion class
Camp Bastion classification
IED blast limb class

Try

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

/api/calc/bastion?bastion_class=1&segmental=false&intraperitoneal_abdomen=false&genital_perineal=false&pelvic_ring=false&upper_limb=false

Full URL: https://api.magentlab.com/api/calc/bastion?bastion_class=1&segmental=false&intraperitoneal_abdomen=false&genital_perineal=false&pelvic_ring=false&upper_limb=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/bastion?bastion_class=1&segmental=false&intraperitoneal_abdomen=false&genital_perineal=false&pelvic_ring=false&upper_limb=false"

Parameters

Name	Type	Required	Description
`bastion_class`	integer	required	Bastion class 1-5 as assigned by the caller: most proximal extent of the lower-limb blast injury (1 injury confined to the foot; 2 lower leg, effective below-knee tourniquet; 3 proximal lower leg or thigh, effective above-knee tourniquet; 4 proximal thigh, tourniquet not effective; 5 any injury with buttock involvement). Jacobs 2014. magent does not examine the casualty.
`segmental`	boolean	required	true when there is potentially viable tissue distal to the most proximal injury (Jacobs 2014: segmental injuries recognised as a distinct entity). Required. magent does not examine the casualty.
`intraperitoneal_abdomen`	boolean	required	true when associated intraperitoneal abdominal injury is present as assigned by the caller (Jacobs 2014). Required. magent does not examine the casualty.
`genital_perineal`	boolean	required	true when associated genital or perineal injury is present as assigned by the caller (Jacobs 2014). Required. magent does not examine the casualty.
`pelvic_ring`	boolean	required	true when associated pelvic ring injury is present as assigned by the caller (Jacobs 2014). Required. magent does not examine the casualty.
`upper_limb`	boolean	required	true when associated upper-limb injury is present as assigned by the caller (Jacobs 2014). Required. magent does not examine the casualty.

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/bastion 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": [
    {
      "bastion_class": "1",
      "genital_perineal": "false",
      "intraperitoneal_abdomen": "false",
      "pelvic_ring": "false",
      "segmental": "false",
      "upper_limb": "false"
    },
    {
      "bastion_class": "1",
      "genital_perineal": "false",
      "intraperitoneal_abdomen": "false",
      "pelvic_ring": "false",
      "segmental": "false",
      "upper_limb": "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/bastion",
  "items": [
    {
      "description": "Injury confined to the foot",
      "components": [
        {
          "value": 1,
          "factor": "bastion_class",
          "met": true
        },
        {
          "factor": "segmental",
          "met": false
        },
        {
          "factor": "intraperitoneal_abdomen",
          "met": false
        },
        {
          "factor": "genital_perineal",
          "met": false
        },
        {
          "factor": "pelvic_ring",
          "met": false
        },
        {
          "factor": "upper_limb",
          "met": false
        },
        {
          "factor": "tourniquet_effective",
          "met": true
        }
      ],
      "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": "Jacobs N, Rourke K, Rutherford J, Hicks A, Smith SR, Templeton P, Adams SA, Jansen JO",
        "doi": "10.1016/j.injury.2012.05.001",
        "id": "jacobs-2014",
        "pmid": "22613453",
        "source": "Injury. 2014;45(9):1422-1428",
        "title": "Lower limb injuries caused by improvised explosive devices: proposed 'Bastion classification' and prospective validation"
      },
      "formula": "bastion",
      "formula_expression": "Caller-assigned Bastion class 1-5 is the most proximal extent of the lower-limb blast injury; associated flags are segmental, intraperitoneal_abdomen, genital_perineal, pelvic_ring, and upper_limb; tourniquet_effective is true for class 1-3 and false for class 4-5 (Jacobs 2014)",
      "bastion_class": 1,
      "genital_perineal": false,
      "intraperitoneal_abdomen": false,
      "pelvic_ring": false,
      "segmental": false,
      "tourniquet_effective": true,
      "upper_limb": false
    },
    {
      "description": "Injury confined to the foot",
      "components": [
        {
          "value": 1,
          "factor": "bastion_class",
          "met": true
        },
        {
          "factor": "segmental",
          "met": false
        },
        {
          "factor": "intraperitoneal_abdomen",
          "met": false
        },
        {
          "factor": "genital_perineal",
          "met": false
        },
        {
          "factor": "pelvic_ring",
          "met": false
        },
        {
          "factor": "upper_limb",
          "met": false
        },
        {
          "factor": "tourniquet_effective",
          "met": true
        }
      ],
      "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": "Jacobs N, Rourke K, Rutherford J, Hicks A, Smith SR, Templeton P, Adams SA, Jansen JO",
        "doi": "10.1016/j.injury.2012.05.001",
        "id": "jacobs-2014",
        "pmid": "22613453",
        "source": "Injury. 2014;45(9):1422-1428",
        "title": "Lower limb injuries caused by improvised explosive devices: proposed 'Bastion classification' and prospective validation"
      },
      "formula": "bastion",
      "formula_expression": "Caller-assigned Bastion class 1-5 is the most proximal extent of the lower-limb blast injury; associated flags are segmental, intraperitoneal_abdomen, genital_perineal, pelvic_ring, and upper_limb; tourniquet_effective is true for class 1-3 and false for class 4-5 (Jacobs 2014)",
      "bastion_class": 1,
      "genital_perineal": false,
      "intraperitoneal_abdomen": false,
      "pelvic_ring": false,
      "segmental": false,
      "tourniquet_effective": true,
      "upper_limb": false
    }
  ]
}

Response

Field	Type	Description
`formula`	string	bastion
`formula_expression`	string	Published Jacobs 2014 Bastion class-plus-flags rule
`bastion_class`	integer	Caller-assigned class 1-5 (most proximal extent)
`description`	string	Jacobs 2014 definition for that class
`segmental`	boolean	Potentially viable tissue distal to the most proximal injury
`intraperitoneal_abdomen`	boolean	Associated intraperitoneal abdominal injury
`genital_perineal`	boolean	Associated genital or perineal injury
`pelvic_ring`	boolean	Associated pelvic ring injury
`upper_limb`	boolean	Associated upper-limb injury
`tourniquet_effective`	boolean	true for class 1-3, false for class 4-5 (from the class definitions)
`components`	array	bastion_class, associated-injury flags, and tourniquet_effective rows
`citation`	object	Jacobs 2014 Bastion classification
`disclaimer`	string	Not a medical device

Example JSON

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

{
  "description": "Injury confined to the foot",
  "components": [
    {
      "value": 1,
      "factor": "bastion_class",
      "met": true
    },
    {
      "factor": "segmental",
      "met": false
    },
    {
      "factor": "intraperitoneal_abdomen",
      "met": false
    },
    {
      "factor": "genital_perineal",
      "met": false
    },
    {
      "factor": "pelvic_ring",
      "met": false
    },
    {
      "factor": "upper_limb",
      "met": false
    },
    {
      "factor": "tourniquet_effective",
      "met": true
    }
  ],
  "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": "Jacobs N, Rourke K, Rutherford J, Hicks A, Smith SR, Templeton P, Adams SA, Jansen JO",
    "doi": "10.1016/j.injury.2012.05.001",
    "id": "jacobs-2014",
    "pmid": "22613453",
    "source": "Injury. 2014;45(9):1422-1428",
    "title": "Lower limb injuries caused by improvised explosive devices: proposed 'Bastion classification' and prospective validation"
  },
  "formula": "bastion",
  "formula_expression": "Caller-assigned Bastion class 1-5 is the most proximal extent of the lower-limb blast injury; associated flags are segmental, intraperitoneal_abdomen, genital_perineal, pelvic_ring, and upper_limb; tourniquet_effective is true for class 1-3 and false for class 4-5 (Jacobs 2014)",
  "bastion_class": 1,
  "genital_perineal": false,
  "intraperitoneal_abdomen": false,
  "pelvic_ring": false,
  "segmental": false,
  "tourniquet_effective": true,
  "upper_limb": false
}

Client errors (HTTP 400)

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

HTTP	Code	When
400	`invalid_bastion_class`	bastion_class must be an integer from 1 to 5 (Jacobs 2014 most proximal extent). Returned before settlement; you are not charged.
400	`invalid_flag`	boolean clinical flags must be true or false Returned before settlement; you are not charged.
400	`invalid_items`	POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
400	`invalid_item_count`	items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
400	`invalid_item`	each items entry must be a JSON object Returned before settlement; you are not charged.

Related tools

MESS — Compute the Johansen 1990 Mangled Extremity Severity Score from caller-assigned skeletal/soft-tissue, limb ischemia, shock, and age integers, doubling ischemia when time exceeds 6 hours, and return the published 0-6 / ≥7 band.
ISS — Compute the Baker 1974 Injury Severity Score as the sum of squares of the three highest caller-assigned AIS body-region grades, or 75 if any region is AIS 6.

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.