# Daugirdas 1993 Kt/V Calculator

> Daugirdas 1993 Kt/V Calculator is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Calculates single-pool variable-volume Kt/V for hemodialysis adequacy using the Daugirdas 1993 second-generation formula

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/kt_v
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/daugirdas-1993-kt-v-calculator-a67a8b3a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dzgT1QDBZtIdoAm_tuhDw

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability daugirdas-1993-kt-v-calculator-a67a8b3a
```

Example prompt: Calculate the Daugirdas 1993 single-pool Kt/V for my patient whose pre-dialysis BUN was 72 mg/dL, post-dialysis BUN was 25 mg/dL, session ran 3.5 hours, ultrafiltration was 2.1 litres, and post-dialysis weight was 74 kg.

## When to prefer this

Use this endpoint when you need a numerically precise, formula-faithful implementation of the Daugirdas 1993 second-generation single-pool variable-volume Kt/V and have all five required inputs (pre-BUN, post-BUN, session time, UF volume, post-dialysis weight). Prefer it over manual calculation to avoid arithmetic errors. Do not use if you need equilibrated eKt/V, standardized Kt/V, urea reduction ratio, or automated KDOQI target assessment — this endpoint computes only the spKt/V scalar.

## Known failure modes

- Missing required parameters (pre_bun_mg_dl, post_bun_mg_dl, session_hours, uf_l) returns a validation error
- BUN values outside 1–200 mg/dL range rejected
- Session hours outside 1.0–8.0 range rejected
- UF volume outside 0–15 litres rejected
- Weight outside 1–500 kg (or 2–1100 lb) rejected
- Providing both weight_kg and weight_lb simultaneously is rejected
- Post-BUN equal to or exceeding pre-BUN produces a mathematically invalid or clinically implausible result
- Payment failure (HTTP 402) if x402 payment header is not supplied

## How this service works

Daugirdas 1993 second-generation single-pool variable-volume Kt/V. Kt/V = -ln(R - 0.008 * t) + (4 - 3.5 * R) * UF / W, with R = post_bun_mg_dl / pre_bun_mg_dl. Numeric Kt/V to 2 decimals. Not a dialysis prescription, not equilibrated eKt/V, not stdKt/V, and not a urea-reduction-ratio tool. magent does not assign KDOQI or other adequacy targets.

## Output

A numeric Kt/V value rounded to 2 decimal places, computed using the Daugirdas 1993 formula: Kt/V = -ln(R - 0.008 * t) + (4 - 3.5 * R) * UF / W, where R is the ratio of post-BUN to pre-BUN. The result represents single-pool variable-volume dialysis dose; it is not an equilibrated eKt/V, not a standardized Kt/V, and KDOQI adequacy target assignment is not included.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "required": [
      "pre_bun_mg_dl",
      "post_bun_mg_dl",
      "session_hours",
      "uf_l"
     ],
     "properties": {
      "uf_l": {
       "type": "number",
       "description": "Ultrafiltration volume in litres (0-15). Daugirdas 1993 UF."
      },
      "weight_kg": {
       "type": "number",
       "description": "Post-dialysis body weight in kilograms (1-500). Provide weight_kg or weight_lb, not both."
      },
      "weight_lb": {
       "type": "number",
       "description": "Post-dialysis body weight in pounds (2-1100). Converted as kg = lb × 0.45359237. Provide weight_kg or weight_lb, not both."
      },
      "pre_bun_mg_dl": {
       "type": "number",
       "description": "Predialysis blood urea nitrogen in mg/dL (1-200). Required with post_bun_mg_dl."
      },
      "session_hours": {
       "type": "number",
       "description": "Hemodialysis session length in hours (1.0-8.0). Daugirdas 1993 t."
      },
      "post_bun_mg_dl": {
       "type": "number",
       "description": "Postdialysis blood urea nitrogen in mg/dL (1-200). Required with pre_bun_mg_dl."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "path": "/api/calc/kt_v",
  "count": 2,
  "items": [
   {
    "kt_v": 1.4,
    "uf_l": 2,
    "formula": "daugirdas_1993",
    "citation": {
     "id": "daugirdas-1993",
     "doi": "10.1681/ASN.V451205",
     "pmid": "8305648",
     "title": "Second generation logarithmic estimates of single-pool variable volume Kt/V: an analysis of error",
     "source": "J Am Soc Nephrol. 1993;4(5):1205-1213",
     "authors": "Daugirdas JT"
    },
    "weight_kg": 70,
    "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.",
    "pre_bun_mg_dl": 80,
    "session_hours": 4,
    "post_bun_mg_dl": 24,
    "formula_expression": "Kt/V = -ln(R - 0.008 * t) + (4 - 3.5 * R) * UF / W"
   },
   {
    "kt_v": 1.4,
    "uf_l": 2,
    "formula": "daugirdas_1993",
    "citation": {
     "id": "daugirdas-1993",
     "doi": "10.1681/ASN.V451205",
     "pmid": "8305648",
     "title": "Second generation logarithmic estimates of single-pool variable volume Kt/V: an analysis of error",
     "source": "J Am Soc Nephrol. 1993;4(5):1205-1213",
     "authors": "Daugirdas JT"
    },
    "weight_kg": 70,
    "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.",
    "pre_bun_mg_dl": 80,
    "session_hours": 4,
    "post_bun_mg_dl": 24,
    "formula_expression": "Kt/V = -ln(R - 0.008 * t) + (4 - 3.5 * R) * UF / W"
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/daugirdas-1993-kt-v-calculator-a67a8b3a/health.json
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