WEDGE
Bicarbonate deficit
Estimate bicarbonate deficit from weight and measured plasma HCO3 using a 50 percent body-weight apparent space.
Markdown: /docs/bicarbonate-deficit.md · Canonical: https://magentlab.com/docs/bicarbonate-deficit
Not a medical device. Not a diagnosis, dose, or listing recommendation.
What it computes
Estimate bicarbonate deficit from weight and measured plasma HCO3 using a 50 percent body-weight apparent space.
When to use
When an agent needs Adrogué–Madias deficit arithmetic and must not invent a bicarbonate space or replacement amount.
When not to use
- Not a treatment order and not a bicarbonate dosing protocol. The paper uses 50 percent of body weight only as a starting space and a safety target near 8–10 mmol/L, not full correction to 24.
- Apparent space can reach 100 percent of body weight or more in extreme acidemia. This tool does not switch space with HCO3, ongoing acid production, or ventilation.
Formula
bicarbonate_space_L = 0.5 * weight_kg; deficit_mEq = bicarbonate_space_L * (desired_hco3 - measured_hco3)
Citation
- Title
- Management of life-threatening acid-base disorders. First of two parts
- Authors
- Adrogué HJ, Madias NE
- Source
- N Engl J Med. 1998;338(1):26-34
Worked example
70 kg, HCO3 4 to 8 mmol/L
Given:
bicarbonate_mmol_l=4desired_hco3_mmol_l=8weight_kg=70
- space = 0.5 × 70 = 35 L (paper starting space, 50 percent of body weight)
- deficit = 35 × (8 − 4) = 140 mEq
Try
Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.
/api/calc/bicarbonate_deficit?weight_kg=70&bicarbonate_mmol_l=4&desired_hco3_mmol_l=8
Full URL: https://api.magentlab.com/api/calc/bicarbonate_deficit?weight_kg=70&bicarbonate_mmol_l=4&desired_hco3_mmol_l=8
x402 V2 curl
Expect HTTP 402 and a PAYMENT-REQUIRED
header 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/bicarbonate_deficit?weight_kg=70&bicarbonate_mmol_l=4&desired_hco3_mmol_l=8"
Cursor mcp.json
Intended config for @magent/mcp. This is not npm @x402/fetch
(a payment fetch wrapper).
{
"mcpServers": {
"magent": {
"args": [
"-y",
"@magent/mcp"
],
"command": "npx",
"env": {
"X402_PRIVATE_KEY": "0xYOUR_SPENDING_KEY"
}
}
}
}
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
weight_kg |
number | optional | Weight in kilograms. Provide weight_kg or weight_lb. |
weight_lb |
number | optional | Weight in pounds. Converted as kg = lb * 0.45359237. |
bicarbonate_mmol_l |
number | required | Measured plasma bicarbonate in mmol/L (same as mEq/L). Range 2-45. |
desired_hco3_mmol_l |
number | optional | Target plasma bicarbonate in mmol/L (8-30), must exceed measured HCO3. Omitted uses 24. |
Bulk (POST)
POST the same path with a JSON items array. Price is n times the GET unit. Invalid items return HTTP 400 before settlement.
- 1 to 25 items. Each item uses the same keys as the GET query parameters.
- 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": [
{
"bicarbonate_mmol_l": "4",
"desired_hco3_mmol_l": "8",
"weight_kg": "70"
},
{
"bicarbonate_mmol_l": "4",
"desired_hco3_mmol_l": "8",
"weight_kg": "70"
}
]
}
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/bicarbonate_deficit",
"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": "Adrogué HJ, Madias NE",
"doi": "10.1056/NEJM199801013380106",
"id": "adrogue-madias-1998",
"source": "N Engl J Med. 1998;338(1):26-34",
"title": "Management of life-threatening acid-base disorders. First of two parts"
},
"formula": "adrogue_madias",
"formula_expression": "bicarbonate_space_L = 0.5 * weight_kg; deficit_mEq = bicarbonate_space_L * (desired_hco3 - measured_hco3)",
"weight_kg": 70.0,
"bicarbonate_mmol_l": 4.0,
"bicarbonate_space_l": 35.0,
"deficit_meq": 140.0,
"desired_hco3_mmol_l": 8.0
},
{
"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": "Adrogué HJ, Madias NE",
"doi": "10.1056/NEJM199801013380106",
"id": "adrogue-madias-1998",
"source": "N Engl J Med. 1998;338(1):26-34",
"title": "Management of life-threatening acid-base disorders. First of two parts"
},
"formula": "adrogue_madias",
"formula_expression": "bicarbonate_space_L = 0.5 * weight_kg; deficit_mEq = bicarbonate_space_L * (desired_hco3 - measured_hco3)",
"weight_kg": 70.0,
"bicarbonate_mmol_l": 4.0,
"bicarbonate_space_l": 35.0,
"deficit_meq": 140.0,
"desired_hco3_mmol_l": 8.0
}
]
}
Response
| Field | Type | Description |
|---|---|---|
formula |
string | adrogue_madias |
formula_expression |
string | Exact expression used |
weight_kg |
number | Normalized weight in kg |
bicarbonate_mmol_l |
number | Measured plasma bicarbonate used |
desired_hco3_mmol_l |
number | Target plasma bicarbonate (24 when omitted) |
bicarbonate_space_l |
number | Apparent bicarbonate space, 0.5 * weight_kg, 1 decimal |
deficit_meq |
number | Estimated bicarbonate deficit in mEq (mmol), 1 decimal |
citation |
object | Adrogué and Madias NEJM 1998 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": "Adrogué HJ, Madias NE",
"doi": "10.1056/NEJM199801013380106",
"id": "adrogue-madias-1998",
"source": "N Engl J Med. 1998;338(1):26-34",
"title": "Management of life-threatening acid-base disorders. First of two parts"
},
"formula": "adrogue_madias",
"formula_expression": "bicarbonate_space_L = 0.5 * weight_kg; deficit_mEq = bicarbonate_space_L * (desired_hco3 - measured_hco3)",
"weight_kg": 70.0,
"bicarbonate_mmol_l": 4.0,
"bicarbonate_space_l": 35.0,
"deficit_meq": 140.0,
"desired_hco3_mmol_l": 8.0
}
Errors
| HTTP | Code | When |
|---|---|---|
| 400 | invalid_weight |
weight_kg (1-500) or weight_lb (2-1100) is required Returned before settlement; you are not charged. |
| 400 | invalid_bicarbonate |
bicarbonate_mmol_l must be a number from 2 to 45. Returned before settlement; you are not charged. |
| 400 | invalid_desired_bicarbonate |
desired_hco3_mmol_l must be a number from 8 to 30 greater than bicarbonate_mmol_l. 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. |
| 402 | payment_required |
Missing or invalid PAYMENT-SIGNATURE; decode the PAYMENT-REQUIRED header |
| 409 | payment_in_progress |
The same authorization nonce is already being settled; retry shortly |
| 429 | rate_limited |
Too many requests from this client |
| 503 | settlement_uncertain |
Settlement is unconfirmed; retry with the same PAYMENT-SIGNATURE |
| 503 | facilitator_unavailable |
Payment facilitator unavailable |
| 503 | facilitator_misconfigured |
Payment facilitator is not configured |
| 503 | facilitator_unauthorized |
Payment facilitator rejected credentials |
| 503 | ledger_unavailable |
Payment ledger unavailable |
| 503 | payment_unavailable |
Payment processing unavailable |
Related tools
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Also searched as
- bicarbonate deficit
- HCO3 deficit
- Adrogue Madias bicarbonate
- bicarb replacement estimate
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. Retry the same URL with PAYMENT-SIGNATURE. Settlement completes before the
tool runs. Full handshake and shared payment errors: Payments.
Guarantees
- Invalid query parameters return HTTP 400 before settlement. You are not charged.
- Settlement finishes before the tool executes. Uncertain settlement fails closed (HTTP 503).
- Execution is timeout-bounded and concurrency-capped.
- Calculator inputs are not persisted. Request logs store path without query.