MAGENT

Hematology · LIVE

Allowable blood loss

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

LIVE $0.005 USDC GET /api/calc/allowable_blood_loss

Markdown: /docs/allowable-blood-loss.md · Canonical: https://magentlab.com/docs/allowable-blood-loss

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

What it computes

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

When to use

When an agent needs published Gross ABL and must not invent milliliters, compute Nadler EBV inside this tool, or use the uncorrected EBV*(Hi-Hf)/Hi form.

When not to use

  • Not a transfusion trigger or order. magent does not choose a product, rate, or threshold.
  • Estimated blood volume is caller-supplied. This tool does not compute Nadler EBV from height, weight, or sex.
  • Dilution-corrected Gross 1983 only. Not the uncorrected EBV * (Hi - Hf) / Hi form.

Formula

abl_ml = estimated_blood_volume_ml * (hct_initial_percent - hct_target_percent) / ((hct_initial_percent + hct_target_percent) / 2)

Citation

Title
Estimating allowable blood loss: corrected for dilution
Authors
Gross JB
Source
Anesthesiology. 1983;58(3):277-280
DOI
10.1097/00000542-198303000-00016

Worked example

EBV 5000 mL, Hct 40 to 30

Given: estimated_blood_volume_ml=5000hct_initial_percent=40hct_target_percent=30

  1. Hct_avg = (40 + 30) / 2 = 35
  2. abl_ml = 5000 * (40 - 30) / 35 = 1428.6 mL

Also searched as

  • allowable blood loss
  • maximum allowable blood loss
  • Gross ABL
  • ABL formula
  • dilution-corrected ABL
  • allowable blood loss hematocrit
  • MABL

Try

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

/api/calc/allowable_blood_loss?estimated_blood_volume_ml=5000&hct_initial_percent=40&hct_target_percent=30

Full URL: https://api.magentlab.com/api/calc/allowable_blood_loss?estimated_blood_volume_ml=5000&hct_initial_percent=40&hct_target_percent=30

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/allowable_blood_loss?estimated_blood_volume_ml=5000&hct_initial_percent=40&hct_target_percent=30"

Parameters

Name Type Required Description
estimated_blood_volume_ml number required Caller-supplied estimated blood volume in mL (50-15000). Required. magent does not compute Nadler EBV.
hct_initial_percent number required Initial hematocrit as a percent (10-70).
hct_target_percent number required Target hematocrit as a percent (10-70). Must be strictly less than hct_initial_percent.

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/allowable_blood_loss 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": [
    {
      "estimated_blood_volume_ml": "5000",
      "hct_initial_percent": "40",
      "hct_target_percent": "30"
    },
    {
      "estimated_blood_volume_ml": "5000",
      "hct_initial_percent": "40",
      "hct_target_percent": "30"
    }
  ]
}

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/allowable_blood_loss",
  "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": "Gross JB",
        "doi": "10.1097/00000542-198303000-00016",
        "id": "gross-1983",
        "source": "Anesthesiology. 1983;58(3):277-280",
        "title": "Estimating allowable blood loss: corrected for dilution"
      },
      "formula": "gross_1983",
      "formula_expression": "abl_ml = estimated_blood_volume_ml * (hct_initial_percent - hct_target_percent) / ((hct_initial_percent + hct_target_percent) / 2)",
      "abl_ml": 1428.6,
      "estimated_blood_volume_ml": 5.0e3,
      "hct_initial_percent": 40.0,
      "hct_target_percent": 30.0
    },
    {
      "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": "Gross JB",
        "doi": "10.1097/00000542-198303000-00016",
        "id": "gross-1983",
        "source": "Anesthesiology. 1983;58(3):277-280",
        "title": "Estimating allowable blood loss: corrected for dilution"
      },
      "formula": "gross_1983",
      "formula_expression": "abl_ml = estimated_blood_volume_ml * (hct_initial_percent - hct_target_percent) / ((hct_initial_percent + hct_target_percent) / 2)",
      "abl_ml": 1428.6,
      "estimated_blood_volume_ml": 5.0e3,
      "hct_initial_percent": 40.0,
      "hct_target_percent": 30.0
    }
  ]
}

Response

Field Type Description
formula string gross_1983
formula_expression string Exact Gross 1983 expression
estimated_blood_volume_ml number Caller-supplied estimated blood volume in mL
hct_initial_percent number Initial hematocrit percent used
hct_target_percent number Target hematocrit percent used
abl_ml number Dilution-corrected allowable blood loss in mL, 1 decimal
citation object Gross Anesthesiology 1983 citation
disclaimer string Not-a-device notice

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": "Gross JB",
    "doi": "10.1097/00000542-198303000-00016",
    "id": "gross-1983",
    "source": "Anesthesiology. 1983;58(3):277-280",
    "title": "Estimating allowable blood loss: corrected for dilution"
  },
  "formula": "gross_1983",
  "formula_expression": "abl_ml = estimated_blood_volume_ml * (hct_initial_percent - hct_target_percent) / ((hct_initial_percent + hct_target_percent) / 2)",
  "abl_ml": 1428.6,
  "estimated_blood_volume_ml": 5.0e3,
  "hct_initial_percent": 40.0,
  "hct_target_percent": 30.0
}

Client errors (HTTP 400)

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

HTTP Code When
400 invalid_estimated_blood_volume estimated_blood_volume_ml must be a number from 50 to 15000. Returned before settlement; you are not charged.
400 invalid_hematocrit hematocrit_percent must be a number from 10 to 70. Returned before settlement; you are not charged.
400 invalid_target_hematocrit hct_target_percent must be 10-70 and strictly less than hct_initial_percent. 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

  • Nadler blood volume — Compute Nadler 1962 predicted blood volume in liters and milliliters from height, weight, and sex.
  • ANC — Compute absolute neutrophil count from WBC and neutrophil plus band percents, plus a Bodey 1966 granulocyte band.

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.
  • 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.