Calculateur Rocktaeschel–Figge de la différence des ions forts apparente (SIDa) à six analytes

État

clinical-review-pending

Version de la méthode

Rocktaeschel et al. 2003 Stewart–Figge six-analyte apparent strong-ion difference arithmetic v1: SIDa (mEq/L) = sodium (mmol/L) + potassium (mmol/L) + 2 × ionized calcium (mmol/L) + 2 × total magnesium (mmol/L) − chloride (mmol/L) − L-lactate (mmol/L). Sodium, potassium, chloride, and L-lactate contribute 1 mEq per mmol; ionized calcium and total magnesium contribute 2 mEq per mmol. Inputs are fixed to mmol/L. Ionized calcium and L-lactate must be final quantitative results from arterial heparinized whole blood analyzed by the blood-gas method; sodium, potassium, chloride, and total magnesium must be final quantitative results from the simultaneously drawn arterial lithium-heparin plasma central-laboratory sample. Output is raw and unrounded in mEq/L. Inclusive software entry/unit-error guardrails are sodium 50–250, potassium 0.5–15, ionized calcium 0.1–10, total magnesium 0.1–10, chloride 20–250, and L-lactate 0–100 mmol/L; these are not clinical reference intervals or thresholds

Population

Adults in an intensive-care setting after a clinician independently establishes applicability of the Rocktaeschel et al. 2003 source protocol. The source comprised 40 critically ill patients with acute renal failure who subsequently required renal replacement therapy for at least 48 hours, 40 APACHE II-matched ICU controls without acute renal failure, and 60 consecutive ICU controls without acute renal failure; acute-renal-failure values were the latest samples before renal replacement therapy, whereas control values were routine morning samples on the day after admission. Use requires one simultaneous arterial assessment: directly measured ionized calcium and L-lactate from an immediately analyzed arterial heparinized whole-blood blood-gas sample, plus sodium, potassium, chloride, and total magnesium from simultaneously drawn arterial lithium-heparin plasma analyzed by the central laboratory. The historical source used a Ciba Corning 865 at 37 °C for blood-gas analytes and a Hitachi 747 for central-laboratory analytes; adult critical-care applicability and patient, collection time, specimen, analyte, mmol/L unit, final quantitative source result, and local assay/method compatibility must be independently verified rather than assumed.

Limites et exclusions

Pediatric or other non-adult use; use outside an independently established adult critical-care and source-protocol context; venous, capillary, serum, or other specimen substitution; measurements from different patients, collection times, or assessments; non-simultaneous blood-gas and central-laboratory samples; or measurements separated by an intervening physiologic change or treatment. · Total, corrected, adjusted, or calculated calcium in place of directly measured ionized calcium; ionized magnesium in place of source-protocol total magnesium; D-lactate, unspecified lactate, or another analyte in place of L-lactate; inferred or converted units; mEq/L, mg/dL, or another unit in place of explicit mmol/L input; or missing, derived, estimated, imputed, default-normal, or nonfinal results. · Unverified patient, timing, specimen, analyte, assay/method, reported-unit, or source-result identity; automatic assumption that a local method reproduces the historical Ciba Corning 865 and Hitachi 747 source methods; incompatible methods; component rounding or clamping before substitution; or modification of the selected equation. · Another published SIDa definition, analyte subset, bedside simplification, or added strong ion; omission of potassium, ionized calcium, total magnesium, or L-lactate; or use as SIDe, SIG, anion gap, a complete Stewart–Figge assessment, weak-acid accounting, or a measure or inference of unmeasured ions. · Any normal band, reference range, cutoff, threshold, high/low or disorder category, acid-base attribution, diagnosis, prognosis, risk estimate, fluid assessment or guidance, replacement or dosing advice, management, treatment, or other clinical decision. · Treating broad software input guardrails as laboratory reference intervals, critical values, validated clinical limits, or proof of source-population applicability; or claiming that this calculator validates specimen integrity, simultaneity, assay performance or bias, or local method compatibility.

• https://doi.org/10.1186/cc2333
• https://pmc.ncbi.nlm.nih.gov/articles/PMC270700/
• https://pubmed.ncbi.nlm.nih.gov/6423247/
• https://doi.org/10.1139/y83-207
• https://doi.org/10.1164/ajrccm.162.6.9904099
• https://doi.org/10.1097/00000542-200305000-00009

Outil importé de la bibliothèque PharmaTek de MDose. Aucune date de révision clinique indépendante n’est documentée dans cette version.

Bibliothèque source

PharmaTek · MDose

Version importée

4b66536936ed

État de publication

Révision clinique en cours