Risk Factors for In-Hospital Mortality in Smoke Inhalation-Associated Acute Lung Injury: Data From 68 United States Hospitals.
BACKGROUND
Mortality after smoke inhalation-associated acute lung injury (SI-ALI) remains substantial. Age and burn surface area are risk factors of mortality, whereas the impact of patient- and center-level variables and treatments on survival are unknown.


METHODS
We performed a retrospective cohort study of burn and non-burn centers at 68 US academic medical centers between 2011 and 2014. Adult inpatients with SI-ALI were identified using an algorithm based on a billing code for respiratory conditions from smoke inhalation who were mechanically ventilated by hospital day 4, with either a length-of-stay ≥ 5 days or death within 4 days of hospitalization. Predictors of in-hospital mortality were identified using logistic regression. The primary outcome was the odds ratio for in-hospital mortality.


RESULTS
A total of 769 patients (52.9 ± 18.1 years) with SI-ALI were analyzed. In-hospital mortality was 26% in the SI-ALI cohort and 50% in patients with ≥ 20% surface burns. In addition to age > 60 years (OR 5.1, 95% CI 2.53-10.26) and ≥ 20% burns (OR 8.7, 95% CI 4.55-16.75), additional risk factors of in-hospital mortality included initial vasopressor use (OR 5.0, 95% CI 3.16-7.91), higher diagnostic-related group-based risk-of-mortality assignment and lower hospital bed capacity (OR 2.3, 95% CI 1.23-4.15). Initial empiric antibiotics (OR 0.93, 95% CI 0.58-1.49) did not impact survival. These new risk factors improved mortality prediction by 9.9% (P < .001).


CONCLUSIONS
In addition to older age and major surface burns, mortality in SI-ALI is predicted by initial vasopressor use, higher diagnostic-related group-based risk-of-mortality assignment, and care at centers with < 500 beds, but not by initial antibiotic therapy.
Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD; Department of Medicine, Massachusetts General Hospital, Boston, MA. Electronic address: sameer.kadri@nih.gov.
Sameer S
SS
Kadri
Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD; Department of Emergency Medicine, West Virginia University, Morgantown, WV.
Andrew C
AC
Miller
University HealthSystem Consortium, Chicago, IL; Department of Health Systems Management, Rush University, Chicago, IL.
Samuel
S
Hohmann
Department of Surgery, Washington University School of Medicine, St. Louis, MO.
Stephanie
S
Bonne
North Carolina Jaycee Burn Center, University of North Carolina Hospital, Chapel Hill, NC.
Carrie
C
Nielsen
Department of General Surgery, Wake Forest Medical Center, Wake Forest School of Medicine, Winston-Salem, NC.
Carmen
C
Wells
Department of General Surgery, Wake Forest Medical Center, Wake Forest School of Medicine, Winston-Salem, NC.
Courtney
C
Gruver
Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Anesthesia, Harvard Medical School, Boston, MA.
Sadeq A
SA
Quraishi
Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD.
Junfeng
J
Sun
Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD.
Rongman
R
Cai
Division of Pulmonary and Critical Care Medicine, Wake Forest Medical Center, Wake Forest School of Medicine, Winston-Salem, NC.
Peter E
PE
Morris
Department of Surgery, Washington University School of Medicine, St. Louis, MO.
Bradley D
BD
Freeman
Department of General Surgery, Wake Forest Medical Center, Wake Forest School of Medicine, Winston-Salem, NC.
James H
JH
Holmes
North Carolina Jaycee Burn Center, University of North Carolina Hospital, Chapel Hill, NC.
Bruce A
BA
Cairns
Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD.
Anthony F
AF
Suffredini
D000046:Academic Medical Centers; D055371:Acute Lung Injury / Q000401:mortality*; D000328:Adult; D000368:Aged; D000465:Algorithms; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D012121:Respiration, Artificial; D012189:Retrospective Studies; D012307:Risk Factors; D015208:Smoke Inhalation Injury / Q000401:mortality*; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology
adult respiratory distress syndrome; burns; epidemiology; risk factors; smoke inhalation