Anion Gap Calculator

Inspectable records

Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Area

Biology, Medicine & Pharmacology (educational estimates only — every panel labeled not-medical-advice)

Tranche

tranche-4

Evidence ID

t4-297

Ledger rows

1

No ledger note is attached.

Review findings

The arithmetic formula is correct for the claimed potassium-excluded anion gap. Keep the supplied educational-only, not-medical-advice label prominent. Resolve the exact normal-range endpoint convention and the handling of lab-specific ranges before release.

Formula and scope findings

• AG=Na−(Cl+HCO3) is the standard potassium-excluded anion-gap formula when all inputs are in consistent units.
• The normal-range flag is underspecified: it does not state whether the 8 and 16 mmol/L endpoints are inclusive, and it does not provide a mechanism for lab-specific reference ranges.
• The specification does not state whether HCO3 means measured serum bicarbonate or BMP total CO2, which is usually used as its clinical proxy.

Unit assumptions

• Na, Cl, and HCO3 must all be supplied in mmol/L; do not mix mmol/L with other units.
• For these monovalent ions, mmol/L and mEq/L have the same numerical values.
• The stated reference interval is assumed to be 8-16 mmol/L and inclusive for the test vectors only.
• No potassium term is included; this is the conventional potassium-excluded anion gap.
• Albumin correction is not performed, so the result is an uncorrected anion gap.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

Extreme finite inputs overflow during Cl + HCO3, producing Infinity and then an anion gap of -Infinity. The calculator should detect overflow or reject the result instead of treating it as a meaningful value.

Errata and corrections

No applied erratum is attached to this unique-name record.

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "Na": 140,
    "Cl": 104,
    "HCO3": 24,
    "units": "mmol/L"
  },
  "expected_outputs": {
    "anion_gap": 12,
    "anion_gap_units": "mmol/L",
    "normal_range_flag": true
  },
  "working": "AG = Na − (Cl + HCO3) = 140 − (104 + 24) = 140 − 128 = 12 mmol/L. Since 8 ≤ 12 ≤ 16, the normal-range flag is true."
}

Related workflows

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json · VERIFIED_CLEAN
• evidence-tranche4/tranche4-results.json
• BOUNDARY_HAZARD_CATALOG.json