# NICE NG29 pediatric IV maintenance

NICE pediatric IV

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/nice_pediatric_iv`
HTML: https://magentlab.com/docs/nice-pediatric-iv
Markdown: https://magentlab.com/docs/nice-pediatric-iv.md

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

## What it computes

Compute NICE NG29 routine IV maintenance for children and young people from Holliday–Segar daily volume, the 1.4.1 sex cap, and the 1.4.9 ADH-risk restriction.

## When to use

When an agent needs NICE NG29 1.4.1/1.4.9 pediatric maintenance milliliters for children and young people and must not invent a volume, apply unreduced Holliday–Segar, use neonate day-of-life table 1.4.2, or apply adult CG174.

## When not to use

- Not a medical device. Deterministic published-formula output only.
- Not a treatment order or IV prescription. Does not choose fluid type, electrolyte additives, or infusion-rate safety limits.
- Children and young people only (NICE NG29 1.4.1 and 1.4.9). Does not implement the term-neonate day-of-life table in 1.4.2.
- Applies the 1.4.1 24-hour caps (males rarely need more than 2500 mL; females rarely need more than 2000 mL) and optional 1.4.9 restriction at 50%, 80%, or 100% of the capped volume. This is not unreduced Holliday–Segar (maintenance-fluids) and not adult NICE CG174.
- Hourly milliliters are restricted_ml / 24 to 1 decimal. The later bedside 4-2-1 mL/kg/h rule is not applied.

## Formula

```
holliday_ml = 100*min(kg,10) + 50*max(0, min(kg,20)-10) + 20*max(0, kg-20); capped_ml = min(holliday_ml, male 2500 else 2000); restricted_ml = capped_ml * restriction_percent / 100; hourly_ml = restricted_ml / 24
```

## Citation

[Intravenous fluid therapy in children and young people in hospital](https://www.nice.org.uk/guidance/ng29)
National Institute for Health and Care Excellence
NICE Guideline NG29. 2015 (updated 2020)
DOI: none

## Worked example

### 30 kg female, no restriction

Given: `restriction_percent=100, sex=female, weight_kg=30`

1. first 10 kg: 100 × 10 = 1000 mL
2. next 10 kg: 50 × 10 = 500 mL
3. remaining 10 kg: 20 × 10 = 200 mL
4. holliday_ml = 1700 mL
5. female cap 2000 mL → capped_ml = min(1700, 2000) = 1700 mL
6. restriction_percent 100 → restricted_ml = 1700 mL
7. hourly_ml = 1700 / 24 = 70.833… → 70.8


### 30 kg male, 50% ADH-risk restriction

Given: `restriction_percent=50, sex=male, weight_kg=30`

1. holliday_ml = 1700 mL
2. male cap 2500 mL → capped_ml = min(1700, 2500) = 1700 mL
3. restriction_percent 50 → restricted_ml = 850 mL
4. hourly_ml = 850 / 24 = 35.416… → 35.4


### 80 kg female, no restriction (1.4.1 cap)

Given: `restriction_percent=100, sex=female, weight_kg=80`

1. holliday_ml = 100×10 + 50×10 + 20×60 = 2700 mL
2. female cap 2000 mL → capped_ml = min(2700, 2000) = 2000 mL
3. restriction_percent 100 → restricted_ml = 2000 mL
4. hourly_ml = 2000 / 24 = 83.333… → 83.3


## Also searched as

- NICE NG29
- pediatric IV fluids
- Holliday Segar NICE
- pediatric maintenance restriction
- NG29 intravenous fluid therapy
- NICE children IV maintenance
- ADH restriction fluids
- pediatric IV maintenance volume

## Parameters

- `weight_kg` (number, optional): Weight in kilograms (1-500). Provide weight_kg or weight_lb.
- `weight_lb` (number, optional): Weight in pounds (2-1100). Converted as kg = lb * 0.45359237.
- `sex` (string, required): Sex for the NICE NG29 1.4.1 24-hour cap (female 2000 mL; male 2500 mL).
- `restriction_percent` (integer, required): NICE NG29 1.4.9 ADH-risk restriction as a percent of the capped daily volume. 50, 80, or 100 (100 = no restriction).

## 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.

Method: `POST /api/calc/nice_pediatric_iv`
Max items: 25
Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic)
Status: 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:

```json
{
  "items": [
    {
      "restriction_percent": "100",
      "sex": "female",
      "weight_kg": "30"
    },
    {
      "restriction_percent": "100",
      "sex": "female",
      "weight_kg": "30"
    }
  ]
}
```

Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/nice-pediatric-iv

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/nice_pediatric_iv",
  "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": "National Institute for Health and Care Excellence",
        "id": "nice-ng29",
        "source": "NICE Guideline NG29. 2015 (updated 2020)",
        "title": "Intravenous fluid therapy in children and young people in hospital"
      },
      "formula": "nice_ng29",
      "formula_expression": "holliday_ml = 100*min(kg,10) + 50*max(0, min(kg,20)-10) + 20*max(0, kg-20); capped_ml = min(holliday_ml, male 2500 else 2000); restricted_ml = capped_ml * restriction_percent / 100; hourly_ml = restricted_ml / 24",
      "sex": "female",
      "weight_kg": 30.0,
      "hourly_ml": 70.8,
      "capped_ml": 1700,
      "holliday_ml": 1700,
      "restricted_ml": 1700,
      "restriction_percent": 100
    },
    {
      "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": "National Institute for Health and Care Excellence",
        "id": "nice-ng29",
        "source": "NICE Guideline NG29. 2015 (updated 2020)",
        "title": "Intravenous fluid therapy in children and young people in hospital"
      },
      "formula": "nice_ng29",
      "formula_expression": "holliday_ml = 100*min(kg,10) + 50*max(0, min(kg,20)-10) + 20*max(0, kg-20); capped_ml = min(holliday_ml, male 2500 else 2000); restricted_ml = capped_ml * restriction_percent / 100; hourly_ml = restricted_ml / 24",
      "sex": "female",
      "weight_kg": 30.0,
      "hourly_ml": 70.8,
      "capped_ml": 1700,
      "holliday_ml": 1700,
      "restricted_ml": 1700,
      "restriction_percent": 100
    }
  ]
}
```

## Response fields

- `formula` (string): nice_ng29
- `formula_expression` (string): Exact expression used
- `weight_kg` (number): Normalized weight in kg
- `sex` (string): female or male
- `restriction_percent` (integer): 50, 80, or 100 (100 = no restriction)
- `holliday_ml` (number): Holliday–Segar daily maintenance water in mL before the 1.4.1 cap
- `capped_ml` (number): min(holliday_ml, 2500 if male else 2000) from NICE NG29 1.4.1
- `restricted_ml` (number): capped_ml * restriction_percent / 100 from NICE NG29 1.4.9
- `hourly_ml` (number): restricted_ml / 24, 1 decimal. Not the later 4-2-1 bedside rule.
- `citation` (object): NICE NG29 2015 (updated 2020) citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "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": "National Institute for Health and Care Excellence",
    "id": "nice-ng29",
    "source": "NICE Guideline NG29. 2015 (updated 2020)",
    "title": "Intravenous fluid therapy in children and young people in hospital"
  },
  "formula": "nice_ng29",
  "formula_expression": "holliday_ml = 100*min(kg,10) + 50*max(0, min(kg,20)-10) + 20*max(0, kg-20); capped_ml = min(holliday_ml, male 2500 else 2000); restricted_ml = capped_ml * restriction_percent / 100; hourly_ml = restricted_ml / 24",
  "sex": "female",
  "weight_kg": 30.0,
  "hourly_ml": 70.8,
  "capped_ml": 1700,
  "holliday_ml": 1700,
  "restricted_ml": 1700,
  "restriction_percent": 100
}
```

## Errors

- HTTP 400 `invalid_nice_pediatric_iv`: NICE NG29 pediatric maintenance inputs must match Holliday-Segar weight, sex for the 2000/2500 mL cap, and restriction_percent 50, 80, or 100 from that guideline. Returned before settlement; you are not charged.
- HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
- HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
- HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged.

Shared HTTP 402 and 503: https://magentlab.com/docs/payments

## Related tools

- [Maintenance fluids](https://magentlab.com/docs/maintenance-fluids) — Compute Holliday–Segar 1957 daily maintenance water from weight, plus the corresponding hourly milliliters.
- [NICE adult IV maintenance](https://magentlab.com/docs/nice-iv-maintenance) — Compute NICE CG174 adult hospital routine maintenance water (20, 25, or 30 mL/kg/day), approximately 1 mmol/kg/day sodium, potassium, and chloride each, and the fixed 50–100 g/day glucose range.
- [Parkland formula](https://magentlab.com/docs/parkland) — Compute adult Parkland 24-hour crystalloid volume from weight and percent TBSA, with half allotted to the first 8 hours from the time of burn.

## 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.

- GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall).
- HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote.
- Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering.
- Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional.
- Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402.

- offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront.
- offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization.

- not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search.

Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers).

Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments

Stdio MCP (one process per host): https://magentlab.com/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.