Medications · LIVE

RhIG vials

Compute ACOG Practice Bulletin 181 RhD immune globulin vial count from caller-assigned fetal-cell percent and maternal blood volume using AABB Technical Manual rounding of FMH/30.

LIVE $0.005 USDC GET /api/calc/rhig

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

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

What it computes

Compute ACOG Practice Bulletin 181 RhD immune globulin vial count from caller-assigned fetal-cell percent and maternal blood volume using AABB Technical Manual rounding of FMH/30.

When to use

When an agent needs ACOG PB 181 vial arithmetic from a caller-assigned Kleihauer–Betke percent and maternal blood volume and must not invent a brand order, read a slide, or skip the AABB extra vial.

When not to use

• Not a prescription or brand order. magent does not name a product, route, or timing.
• magent does not interpret Kleihauer–Betke slides. fetal_cells_percent is the percent assigned by the caller.
• maternal_blood_volume_ml is caller-assigned. magent does not compute Nadler estimated blood volume.
• Society-policy AABB rounding of whole-blood FMH / 30 only. magent does not convert a red-cell volume path or a flow-cytometry method.

Formula

fmh_ml = fetal_cells_percent / 100 * maternal_blood_volume_ml; raw = fmh_ml / 30; vials = (frac(raw) >= 0.5 ? ceil(raw) : floor(raw)) + 1

Citation

Title

Prevention of Rh D Alloimmunization

Authors

Committee on Practice Bulletins-Obstetrics

Source

Obstet Gynecol. 2017;130(2):e57-e70

DOI

10.1097/AOG.0000000000002232

Worked example

Also searched as

• RhIG vials
• RhD immune globulin
• fetomaternal hemorrhage vials
• Kleihauer-Betke vial count
• ACOG RhIG
• 300 microgram RhIG
• FMH RhIG dose

Try

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

/api/calc/rhig?fetal_cells_percent=0.4&maternal_blood_volume_ml=5000

Full URL: https://api.magentlab.com/api/calc/rhig?fetal_cells_percent=0.4&maternal_blood_volume_ml=5000

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/rhig?fetal_cells_percent=0.4&maternal_blood_volume_ml=5000"

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/rhig 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": [
    {
      "fetal_cells_percent": "0.4",
      "maternal_blood_volume_ml": "5000"
    },
    {
      "fetal_cells_percent": "0.4",
      "maternal_blood_volume_ml": "5000"
    }
  ]
}

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/rhig",
  "items": [
    {
      "raw": 0.667,
      "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": "Committee on Practice Bulletins-Obstetrics",
        "doi": "10.1097/AOG.0000000000002232",
        "id": "acog-2017-181",
        "pmid": "28742673",
        "source": "Obstet Gynecol. 2017;130(2):e57-e70",
        "title": "Prevention of Rh D Alloimmunization"
      },
      "formula": "acog_pb_181",
      "formula_expression": "fmh_ml = fetal_cells_percent / 100 * maternal_blood_volume_ml; raw = fmh_ml / 30; vials = (frac(raw) >= 0.5 ? ceil(raw) : floor(raw)) + 1",
      "fetal_cells_percent": 0.4,
      "fmh_ml": 20.0,
      "maternal_blood_volume_ml": 5.0e3,
      "vial_micrograms": 300,
      "vials": 2
    },
    {
      "raw": 0.667,
      "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": "Committee on Practice Bulletins-Obstetrics",
        "doi": "10.1097/AOG.0000000000002232",
        "id": "acog-2017-181",
        "pmid": "28742673",
        "source": "Obstet Gynecol. 2017;130(2):e57-e70",
        "title": "Prevention of Rh D Alloimmunization"
      },
      "formula": "acog_pb_181",
      "formula_expression": "fmh_ml = fetal_cells_percent / 100 * maternal_blood_volume_ml; raw = fmh_ml / 30; vials = (frac(raw) >= 0.5 ? ceil(raw) : floor(raw)) + 1",
      "fetal_cells_percent": 0.4,
      "fmh_ml": 20.0,
      "maternal_blood_volume_ml": 5.0e3,
      "vial_micrograms": 300,
      "vials": 2
    }
  ]
}

Response

Example JSON

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

{
  "raw": 0.667,
  "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": "Committee on Practice Bulletins-Obstetrics",
    "doi": "10.1097/AOG.0000000000002232",
    "id": "acog-2017-181",
    "pmid": "28742673",
    "source": "Obstet Gynecol. 2017;130(2):e57-e70",
    "title": "Prevention of Rh D Alloimmunization"
  },
  "formula": "acog_pb_181",
  "formula_expression": "fmh_ml = fetal_cells_percent / 100 * maternal_blood_volume_ml; raw = fmh_ml / 30; vials = (frac(raw) >= 0.5 ? ceil(raw) : floor(raw)) + 1",
  "fetal_cells_percent": 0.4,
  "fmh_ml": 20.0,
  "maternal_blood_volume_ml": 5.0e3,
  "vial_micrograms": 300,
  "vials": 2
}

Client errors (HTTP 400)

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

Related tools

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• Allowable blood loss — Compute Gross 1983 dilution-corrected allowable blood loss from a caller-supplied estimated blood volume and initial versus target hematocrit.

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.