Revised Baux Score: Predictive mortality score for adult burn patients.
Risk Prediction
Enter patient age and burn area to calculate the mortality probability using the Revised Baux Score.
Guidelines & Evidence
Verified
Last Review: 2026-07-17
When to Use
When to Use
The Revised Baux Score is used for rapid bedside estimation of mortality probability in adult burn patients. It is simple enough for mental calculation and designed for use in triage settings, burn center referral decisions, and goals-of-care discussions. It supersedes the original Baux score (1961) by incorporating the independent mortality contribution of inhalation injury.
Primary Indications
Adult patients (age ≥ 18 years) with acute thermal burn injuries
Rapid mortality risk stratification at initial assessment
Burn center transfer decisions — mortality estimate informs level-of-care urgency
Goals-of-care and family counseling in massive thermal injuries
Cross-checking ABSI estimate at the bedside
When NOT to Use
Pediatric patients (< 18 years) — Baux score was derived and validated in adult cohorts
Chemical or electrical burns (distinct pathophysiology)
As a definitive palliation criterion — always supplement with ABSI and multidisciplinary review
When %TBSA cannot be accurately estimated (Lund-Browder preferred over Rule of Nines for accuracy)
How it Works
Formula
Revised Baux Score = Age (years) + % TBSA burned + 17 × [Inhalation Injury: 1 = yes, 0 = no]
Variable Derivation
Using logistic regression on 39,888 burned patients from the National Burn Repository (ABA), Osler et al. (2010) demonstrated that age and %TBSA contribute near-equally to burn mortality. Inhalation injury added the equivalent of 17 additional years of age (or 17% additional TBSA) to predicted mortality — the source of the "+17" constant. This constant was derived from the regression coefficient of inhalation injury in the single-term logistic model anchored to the Baux score framework.
Approximate Mortality Estimates
| Score ≤ 60 | Low mortality risk (< 10%) |
| Score 61–80 | Moderate risk (~10–30%) |
| Score 81–100 | High risk (~30–60%) |
| Score 101–120 | Very high risk (~60–90%) |
| Score > 120 | Expected mortality > 90% |
Inhalation Injury Assessment
Clinical indicators: hoarseness, stridor, carbonaceous sputum, singed nasal hairs, facial burns, confined-space fire exposure
Confirm with bronchoscopy when available — gold standard (erythema, edema, carbonaceous deposits in airway)
Inhalation injury is binary (present/absent) in the Revised Baux formula — no grading is incorporated
Clinical Pearls
Key Strengths
Validated in the largest burn dataset used for any burn mortality score (n=39,888 from ABA National Burn Repository).
Simple enough for rapid bedside mental arithmetic — no calculator required.
More accurate than the original Baux score (which chronically over-predicted mortality in the modern era of early excision/grafting and advanced critical care).
Correlates well with logistic regression models using the same three predictors — precision improves marginally with inverse logit transformation but directional accuracy is equivalent.
Limitations
Performance is slightly inferior to the full logistic regression model — for precise probability estimates, inverse logit transformation of the Revised Baux Score is recommended.
Pediatric mortality curves differ substantially from adults; do not apply to patients < 18 years.
TBSA estimation is notoriously variable — Rule of Nines may overestimate in obese patients; use Lund-Browder chart where accuracy matters.
The +17 inhalation injury constant was derived from a US cohort and may not precisely generalize internationally due to differences in early intubation thresholds and ventilator practices.
Does not incorporate wound depth, comorbidities, or pre-burn functional status — all independently affect outcomes.
Comparator: ABSI
ABSI incorporates sex, full-thickness burn, and a non-linear TBSA weighting, making it more granular than Revised Baux. Use both in parallel: Revised Baux for rapid bedside communication; ABSI for formal triage documentation. For family discussions, translating the Revised Baux Score to an approximate mortality percentage is accessible and actionable.
Next Steps
Score ≤ 60 (Low Risk, < 10% predicted mortality)
01
Standard burn unit management — fluid resuscitation per Parkland formula (4 mL/kg/%TBSA over 24h, half in first 8h).
02
Early wound assessment — determine depth (superficial partial, deep partial, full thickness).
03
Early excision and grafting for full-thickness areas.
04
Physical and occupational therapy from day 1.
Score 61–100 (Moderate to High Risk)
01
ICU admission — invasive hemodynamic monitoring, mechanical ventilation if inhalation injury.
02
Burn center involvement mandatory if not already present.
03
Nutritional support — early enteral feeding (within 6 hours); target 25–30 kcal/kg/day with protein loading.
04
Goals-of-care discussion initiated with family — document patient's pre-injury preferences.
Score > 100 (Very High to Critical Risk, > 60% mortality)
01
Multidisciplinary team meeting: burn surgery, intensivist, palliative care, ethics.
02
Shared decision-making: aggressive resuscitation vs. comfort-focused care — document in writing.
03
If proceeding with aggressive management: early major excision/grafting is the only intervention with established mortality benefit in this range.
04
Consider withdrawal of life-sustaining treatment in consultation with family if consistent with patient values and futility criteria are met.
The Evidence
Derivation Study (Revised Baux Score)
Simplified estimates of the probability of death after burn injuries: extending and updating the Baux score.
Osler T et al. • J Trauma.. 2010;68(3):690-7. n=39,888 patients from ABA National Burn Repository. Logistic regression; inhalation injury shown to add equivalent of 17 years of age or 17% TBSA to mortality risk. Revised Baux Score formula established.
View SourceOriginal Baux Score Reference
Contribution à l'étude du traitement local des brûlures thermiques étendues.
Baux S. • Thesis. Paris.. 1961;Original derivation of Age + %TBSA as a simple burn mortality rule of thumb. No PMID — pre-PubMed era publication.
External Links
Origins & History
The original Baux score was introduced by French surgeon Serge Baux in his 1961 Paris thesis as a simple rule: Age + %TBSA ≈ the probability of death (expressed as a percentage). While clinically intuitive, advances in burn care (early excision and grafting, intensive fluid resuscitation, antibiotic prophylaxis, specialized burn ICUs) rendered its mortality predictions increasingly pessimistic. The Revised Baux Score was published in 2010 by Dr. Turner Osler, Dr. Laurent Glance, and Dr. David Hosmer at the University of Vermont, recalibrating predictions using modern data from 39,888 patients across the American Burn Association National Burn Repository. The "+17" inhalation injury penalty emerged directly from logistic regression and provides the score with clinically validated additional precision over its predecessor.
Last Comprehensive Review: 2026-07-17