Analysis of Factors Affecting In-Hospital Survival Rate and Morbidity in Elderly Burn in Thailand Patients: A Retrospective Review

Wongsathorn Meepiarn; Sasima Tongsai; Pornprom  Muangman; Kusuma Chinaroonchai

doi:10.33192/smj.v78i11.284767

Authors

Wongsathorn Meepiarn, M.D. Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Sasima Tongsai, Ph.D Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Pornprom Muangman, M.D. Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Kusuma Chinaroonchai, M.D. Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand

DOI:

https://doi.org/10.33192/smj.v78i11.284767

Keywords:

Elderly burn, 30-day overall survival, in-hospital mortality, inhalation injury, acute renal failure

Abstract

Objective: To identify factors associated with 30-day overall survival (OS), in-hospital mortality, acute renal failure (ARF), and volume overload (VO) in elderly burn patients.

Materials and Methods: A retrospective review of 106 elderly patients (aged ≥ 60 years) admitted to Siriraj Hospital (2002–2021) was conducted. Thirty-day OS was analyzed using Firth-penalized Cox proportional-hazards regression. Binary outcomes (ARF, VO, in-hospital mortality) were evaluated using Firth-penalized binary logistic regression.

Results: The mean age was 71.0 ± 8.4 years with a median burn size of 29.5% TBSA. Thirty-day and in-hospital mortalities were 14.2% and 32.1%, respectively. Shorter 30-day survival was associated with inhalation injury (adjusted HR [aHR] 7.00), shock on arrival (aHR 9.00), respiratory rate > 20/min (aHR 12.25), and burn size (aHR 1.033 per 1% TBSA). ARF was linked to shock, TBSA ≥ 25%, higher admission creatinine, and lower albumin. Sepsis was the sole risk factor for in-hospital mortality (aOR 6.01). Older age and larger burn size correlated with VO, and hemodialysis was significantly more frequent among 30-day nonsurvivors.

Conclusions: Non-infectious factors—inhalation injury, shock, tachypnea, and burn size—predict 30-day survival, whereas sepsis drives in-hospital mortality. Aggressive management of acute renal failure to avoid hemodialysis may improve short-term outcomes in elderly burn cohorts.

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