Nephrology and acid-base tools
Renal function, fluid, electrolyte, and acid-base math with the primary citation under every result.
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eGFR under the 2021 race-free CKD-EPI equation, Cockcroft-Gault, FeNa and FeUrea, KDIGO AKI staging, anion gap (with delta-delta and corrected variants), osmolal gap, SAAG, Winters formula, ABG interpretation, maintenance fluids, sodium correction with the free-water deficit, corrected calcium and sodium.
24 tools in this topic, all free, all in your browser.
Tools in this topic
- Estimated GFR (CKD-EPI 2021) Estimate glomerular filtration rate using the 2021 CKD-EPI creatinine-only equation, which the National…
- eGFR Suite (CKD-EPI 2021 / MDRD / CG) Estimate glomerular filtration rate using three published equations side by side.
- CKD-EPI 2021 Cystatin-C eGFR (race-free) The 2021 race-free CKD-EPI eGFR.
- Cockcroft-Gault Creatinine Clearance Estimate creatinine clearance using the original Cockcroft-Gault formula (Nephron 1976).
- FENa / FEUrea Compute the fractional excretion of sodium (FENa, Espinel 1976) and the fractional excretion of urea…
- KDIGO AKI Staging Stage acute kidney injury per the KDIGO 2012 clinical practice guideline using the serum-creatinine criteria.
- KDIGO CKD Staging (G×A risk) KDIGO CKD staging: G-stage by eGFR and A-stage by UACR (or a direct albuminuria category) mapped to the…
- Urine Albumin/Protein-to-Creatinine Ratio Spot urine albumin- and protein-to-creatinine ratios with the KDIGO A-stage and an estimated 24-hour…
- Dialysis Adequacy (URR + Kt/V) Hemodialysis adequacy: urea reduction ratio (URR) and the Daugirdas second-generation single-pool Kt/V…
- Mehran Contrast-Induced Nephropathy Risk Mehran contrast-induced nephropathy risk score after PCI (weighted points, bands <=5 / 6-10 / 11-15 / >=16)…
- Anion Gap Compute the anion gap (Na - (Cl + HCO3)) and the albumin-corrected anion gap (+2.5 mEq/L per 1 g/dL drop below 4.0).
- Albumin-Corrected Anion Gap (Figge) Apply the Figge correction to the anion gap to account for hypoalbuminemia.
- Anion Gap & Delta-Delta Compute the serum anion gap (Na - (Cl + HCO3)), albumin-correct it when albumin is below 4 g/dL, and run the…
- Osmolal Gap Compute the calculated serum osmolality from sodium, glucose, BUN, and (optionally) ethanol, then subtract…
- SAAG (Serum-Ascites Albumin Gradient) Calculate the serum-ascites albumin gradient (SAAG) by subtracting the ascitic-fluid albumin from a serum…
- Winters Formula (expected PaCO2) Compute the Winters formula for expected respiratory compensation in metabolic acidosis.
- ABG Interpretation Walkthrough Walk a blood-gas tuple (pH, PaCO2, HCO3, and optionally PaO2 / FiO2) through the standard acid-base…
- Sodium Correction Rate Planner (Adrogue-Madias) Build an Adrogue-Madias correction plan for hypo- or hypernatremia.
- Free Water Deficit Calculator Estimate the free-water deficit in hypernatremia using the classic total-body-water formula…
- Corrected Sodium for Hyperglycemia Compute glucose-corrected serum sodium using both of the published correction factors so the clinician can see them side by side.
- Corrected Calcium for Albumin Estimate albumin-corrected serum calcium with Payne's formula: corrected Ca = measured Ca + 0.8 x (4.0 - albumin g/dL).
- Corrected Calcium / Sodium Suite Two bedside corrections in one tool.
- Maintenance Fluids (4-2-1) Compute pediatric maintenance IV fluid rate using the Holliday-Segar 4-2-1 rule.
- Iron Deficit Calculator (Ganzoni) Apply the Ganzoni equation (Ganzoni 1970) to estimate total body iron deficit in milligrams from body weight…