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Compare kidney-function formulas, dialysis adequacy metrics, and renal medication math in an educational workflow that avoids patient-specific dosing or diagnosis.
New to this workflow? Follow the steps in order, starting with the first tool below. Already know what you need? Jump straight to the matching step — every tool in this workflow is listed in the comparison table.
First tool: Creatinine Clearance Calculator (Cockcroft-Gault)
Hubs
| Tool | What it does | Category |
|---|---|---|
| Creatinine Clearance Calculator (Cockcroft-Gault) | Estimate creatinine clearance (CrCl) with the Cockcroft-Gault equation: CrCl (mL/min) = [(140 − Age) × Weight(kg)] / [72 × SCr(mg/dL)] × 0.85 if female. Choose the weight basis: Actual Body Weight (ABW), Ideal Body Weight (IBW, Devine 1974), or Adjusted Body Weight (AdjBW = IBW + 0.4 × (ABW − IBW), for obese patients). Optional SCr floor at 1.0 mg/dL for elderly / low-muscle-mass patients. Returns an UN-indexed CrCl in mL/min — the value drug-dosing tables use (for BSA-indexed eGFR use MDRD or CKD-EPI). Derived from Cockcroft & Gault, Nephron 1976. Valid for stable renal function in adults. Not medical advice. | Health |
| eGFR Calculator (CKD-EPI 2021 Race-Free) | Estimate glomerular filtration rate (eGFR) with the CKD-EPI 2021 race-free creatinine equation: eGFR = 142 × min(SCr/κ, 1)^α × max(SCr/κ, 1)^(−1.200) × 0.9938^Age × 1.012 if female, where κ = 0.7 (female) / 0.9 (male) and α = −0.241 (female) / −0.302 (male). This 2021 update (Inker et al., NEJM 2021) removed the race multiplier from the 2009 equation and changed the leading coefficient from 141 to 142. Returns a BSA-INDEXED eGFR for CKD staging (G1–G5); for drug dosing use un-indexed CrCl (Cockcroft-Gault). Valid for stable adults, not AKI/pregnancy/amputees/extremes. Not medical advice. |
Hubs
| Health |
| eGFR Calculator (MDRD Simplified) | Estimate glomerular filtration rate (eGFR) with the simplified 4-variable MDRD equation (2006 re-expressed, IDMS-traceable): eGFR (mL/min/1.73 m²) = 175 × SCr^−1.154 × Age^−0.203 × (0.742 if female) × (1.212 if Black). The 175 constant replaced the original 186 after IDMS-standardized creatinine calibration. The legacy race coefficient 1.212 is OFF by default (the 2021 CKD-EPI race-free equation removed it) and is provided only for historical comparison. Returns a BSA-INDEXED eGFR for CKD staging (G1–G5); for drug dosing use un-indexed CrCl (Cockcroft-Gault). Derived from Levey AS et al., Ann Intern Med 2006. Valid for stable adults, not AKI/pregnancy/extremes. Not medical advice. | Health |
| Pediatric eGFR Calculator (Schwartz) | Estimate glomerular filtration rate (eGFR) in children (1–18 y) with the Schwartz formula. 2009 Bedside version (recommended, IDMS-traceable creatinine): eGFR = 0.413 × Height(cm) / SCr(mg/dL). 1984 Original version (legacy, pre-IDMS assays): eGFR = 0.55 × Height(cm) / SCr(mg/dL). The coefficient dropped from 0.55 to 0.413 because IDMS-standardized assays return lower creatinine values. Returns a BSA-INDEXED eGFR in mL/min/1.73 m². Derived from Schwartz GJ et al., Am J Kidney Dis 2009 (0.413) and Pediatrics 1976 (0.55). Valid for pediatric stable renal function; use CKD-EPI/MDRD for adults, not for neonates/AKI. Not medical advice. | Health |
| Fractional Excretion of Sodium (FENa) | Calculate the Fractional Excretion of Sodium (FENa) to differentiate prerenal from intrinsic acute kidney injury: FENa (%) = [U_Na × S_Cr] / [S_Na × U_Cr] × 100. In oliguric AKI, FENa <1% suggests prerenal azotemia (sodium-avid state: volume depletion, heart failure, hepatorenal syndrome), while FENa ≥1% suggests intrinsic injury (typically ATN). FENa >4% is sometimes cited as supportive of post-obstructive pathology. Caveats: unreliable on diuretics (use FEUrea <35%), contrast/sepsis ATN can present with low FENa, chronic CKD and glucosuria elevate FENa independently. Derived from Espinel CH, JAMA 1976. Most useful in oliguric AKI; interpret with full clinical context. Not medical advice. | Health |
| Urea Reduction Ratio (URR) — Dialysis Adequacy | Calculate the Urea Reduction Ratio (URR) for a single hemodialysis session: URR (%) = (Pre-BUN − Post-BUN) / Pre-BUN × 100. KDOQI recommends a minimum URR ≥65% and a target dose ≥70%. URR is a simple adequacy marker but is being phased out in favor of Kt/V, which also accounts for urea generation and volume contraction. Derived from the KDOQI Clinical Practice Guideline for Hemodialysis Adequacy. Valid for single hemodialysis sessions with BUN drawn pre- and immediately post-treatment; not for peritoneal dialysis. Not medical advice. | Health |
| Dialysis Dose Kt/V Calculator (Daugirdas 2nd Gen.) | Estimate single-pool Kt/V (spKt/V) for a hemodialysis session with the Daugirdas second-generation formula: Kt/V = −ln(R − 0.008·t) + (4 − 3.5·R) × UF / W, where R = Post-BUN/Pre-BUN, t = treatment time (h), UF = ultrafiltration volume (kg), W = post-dialysis weight (kg). The first term captures urea removal and generation; the second corrects for volume contraction. KDOQI target: spKt/V ≥1.2 per session (minimum delivered dose) for conventional thrice-weekly hemodialysis, target ~1.4. Requires post-dialysis BUN drawn by slow-flow/stop-pump technique. Derived from Daugirdas JT, J Am Soc Nephrol 1993. Valid for intermittent hemodialysis; not for peritoneal dialysis or CRRT/SLED. Not medical advice. | Health |
| Renal Drug Dose Adjustment Helper | Categorize renal function from creatinine clearance (CrCl) and provide FDA/KDIGO-aligned dosing guidance: Normal (CrCl ≥60) → standard dosing; Mild (30–59) → consider dose reduction or interval extension; Moderate (15–29) → reduction and/or extension typically required; Severe (<15) → significant reduction, many drugs contraindicated or post-dialysis only. Outlines two adjustment strategies: (A) interval extension for concentration-dependent drugs (aminoglycosides, vancomycin), (B) dose reduction for time-dependent drugs (β-lactams). Dialysis toggle flags the need for post-dialysis supplementation per the specific drug label. Derived from FDA Pharmacokinetics Guidance, the KDIGO Drug Dosing Consensus, and NIDDK guidance. This tool does NOT replace the FDA-approved package insert for any specific drug. Not medical advice. | Health |
| Drug Clearance Calculator (CL) | Calculate drug clearance CL in two modes. (A) Definition: CL = elimination rate / concentration, valid for any pharmacokinetic model. (B) Linear first-order: CL = k · Vd (or derive k from t½ via k = ln2 / t½). Also reports the relationship t½ = 0.693 · Vd / CL. CL is a definitional parameter independent of Vd. Linear mode applies only to first-order elimination — NOT to Michaelis-Menten drugs (phenytoin, high-dose ethanol). Reference: theophylline CL ≈ 2.8 L/h in a 70 kg non-smoking adult. Not medical advice. | Health |
| Vancomycin Empiric Dosing Calculator (2020 ASHP/IDSA) | Empiric starting dosing for vancomycin per the 2020 ASHP/IDSA/PIDS/SIDP consensus guideline. Loading dose: 20–25 mg/kg actual body weight (obesity cap 3000 mg). Maintenance dose: 15–20 mg/kg actual body weight every 8–12 h. Optional creatinine clearance (CrCl) input suggests an empiric dosing interval (≥90 → q8h, 50–89 → q12h, 30–49 → q18–24h, 10–29 → q24h, <10 → q24–48h). Optional measured trough is classified against the SECONDARY trough target of 15–20 mg/L. The 2020 guideline shifted the primary monitoring target to AUC₀₋₂₄/MIC = 400–600 mg·h/L (within first 24–48 h); trough-only monitoring is no longer recommended as primary. Derived from Rybak MJ et al., Am J Health-Syst Pharm 2020. Empiric start doses ONLY — individualize by AUC-guided Bayesian monitoring. Not medical advice. | Health |
Renal formulas can look precise, but this workflow is designed for teaching, simulation, and QA review only. Start by confirming that the inputs are fictional or de-identified test fixtures and that no output will be used to diagnose disease, prescribe dialysis, or select a medication dose for a real person.
Use creatinine-clearance-cockcroft, egfr-ckd-epi, and egfr-mdrd to compare adult renal-function estimates, and use schwartz-pediatric-gfr only when the example is explicitly pediatric. Then move to fractional-excretion-sodium for sodium-handling context and to urea-reduction-ratio plus kt-v-dialysis-dose for dialysis adequacy math. These outputs should be documented with units, timing, and population assumptions before any comparison is made.
renal-dose-adjustment, drug-clearance-calculator, and vancomycin-dosing belong in this workflow only as educational model checks. Their role is to expose assumptions, compare intermediate values, and help reviewers find inconsistent units or missing monitoring context. The final note should say what was checked, which assumptions were uncertain, and why the result is not patient-specific advice.
Workflow playbook
Compare adult creatinine clearance and eGFR equations, or use the pediatric Schwartz equation for child teaching cases, while keeping the population and unit assumptions explicit.
Use FENa for sodium-handling scenario discussion and URR plus Kt/V for dialysis-session adequacy math, without converting these values into diagnosis or treatment orders.
Check renal-dose adjustment, drug-clearance, and vancomycin teaching examples as formula demonstrations only, then flag any missing label, monitoring, or patient-context assumption.
Compare whether filtration estimates, dialysis adequacy values, and medication-model calculations tell a consistent educational story, and record why the result is not a clinical instruction.
Continue only when the calculations support teaching, scenario design, or software QA. Stop if the result could determine diagnosis, treatment, dialysis prescription, or a real medication dose.
Use Cockcroft-Gault for creatinine-clearance teaching examples, CKD-EPI or MDRD for adult eGFR comparison, Schwartz for pediatric examples, FENa for sodium-handling context, and URR or Kt/V for dialysis adequacy math.