Why bound the inputs?

Below 1.0, ln becomes negative and inflates score artificially. Above creatinine 4.0, the score saturates — values aren't additive predictive past renal failure.

When is MELD-Na = MELD?

When MELD ≤ 11 OR Na = 137. UNOS only applies the Na correction if MELD > 11.

MELD vs. MELD-Na vs. MELD 3.0?

Original MELD: 2001. MELD-Na: 2016 UNOS. MELD 3.0 (Kim WR, Gastroenterology 2021;161:1887): adds sex + albumin + adjusts terms. UNOS adopted MELD 3.0 in July 2023.

Is this medical advice?

No. UNOS allocation involves exception points (HCC, refractory ascites, etc.), MELD 3.0 (current), and individualized assessment.

MELD-Na Score Calculator (Liver Allocation)

MELD-Na = MELD + 1.32 × (137 − Na) − [0.033 × MELD × (137 − Na)]. UNOS 2016 update; Kim 2008 NEJM.

Result

MELD-Na

Raw MELD 13; Na 135. ~6% 3-month mortality.

Creatinine used1.00 mg/dL
Bilirubin used1.50 mg/dL
INR used1.50
Sodium used135 mEq/L
On HD ×2 in 7d?No
Raw MELD13
MELD-Na15
3-month mortality~6% 3-month mortality

MELD-Na 15— ~6% 3-month mortality

6 MELD-Na15 MELD-Na40 MELD-Na

3-month mortality bands from the original MELD validation (Wiesner 2003 Gastroenterology 124:91). UNOS caps the score at 40.

Source: Kim WR et al., "Hyponatremia and mortality among patients on the liver-transplant waiting list." NEJM 2008;359(10):1018–26. UNOS allocation policy.

Not medical advice — UNOS adopted MELD 3.0 (Kim 2021, Gastroenterology 161:1887) for allocation in July 2023; this calculator implements the 2016 MELD-Na rule. Allocation involves exception points (HCC, refractory ascites) beyond the score. Not a transplant decision tool.

Step-by-step

MELD = round(10 × (0.957·ln(creat) + 0.378·ln(bili) + 1.120·ln(INR) + 0.643)).
= round(10 × (0.0000 + 0.1533 + 0.4541 + 0.643)) = 13.
MELD-Na = MELD + 1.32 × (137 − Na) − 0.033 × MELD × (137 − Na) = 13 + 2.64 − 0.86 = 15.

How to use this calculator

Enter creatinine, bilirubin, INR, sodium.
Indicate if patient has been on HD ≥2× in past week.
Read MELD-Na — UNOS uses this for transplant priority (higher = sicker, higher priority).

About this calculator

MELD-Na (Model for End-Stage Liver Disease with Sodium) is the score used by UNOS for liver-transplant allocation in the US since 2016. Original MELD (Kamath PS et al., Hepatology 2001) used creatinine/bilirubin/INR; sodium added (Kim WR et al., NEJM 2008;359:1018) because hyponatremia independently predicts mortality. Per OPTN/UNOS: bound creatinine, bilirubin, INR ≥ 1.0; cap creatinine at 4.0 (or set to 4.0 if HD ≥ 2× in 7 days); bound Na to [125, 137]; cap final MELD-Na at 40. **Not medical advice — transplant decisions involve much more than this score.**

Frequently asked

Kim WR et al., "Hyponatremia and mortality among patients on the liver-transplant waiting list." NEJM 2008;359(10):1018-26. Adopted by UNOS for allocation in January 2016.