Inhalation injury and clinical course in major burned patients

Introduction

Inhalation injury is the primary determinant of mortality in major burned patients, particularly when associated with pneumonia. This study sought to describe the association between severity of inhalation injury on bronchoscopic examination and clinical course among fire victims of Santa Maria, RS, Brazil. Two hundred and forty-two people were killed in the disaster.

Methods

Eighteen patients with inhalation injury secondary to smoke and fire exposure in an enclosed space admitted to Hospital de Clínicas de Porto Alegre were divided into groups according to the severity of injury as determined by bronchoscopic criteria: grade 1 (moderate edema and hyperemia), grade 2 (marked edema and hyperemia, with or without carbonaceous debris), or grade 3 (mucosal ulceration or necrosis). Duration of mechanical ventilation (MV), length of ICU stay, overall length of hospital stay, and PaO₂/FiO₂ ratio on days 1 and 3 were compared among these groups by means of ANOVA with Tukey's post-hoc correction.

Results

Three patients had grade 1 injury, four had grade 2 injury, and 11 had grade 3 injury. Seven patients developed ventilator-associated pneumonia. Mean duration of MV increased progressively in relation to injury severity (grade 1: 2.7 ± 0.6 days vs. grade 2: 5.7 ± 2.1 days vs. grade 3: 13.0 ± 5.4 days; P = 0.004), as did length of ICU stay (grade 1: 4 days vs. grade 2: 7.2 ± 2.2 days vs. grade 3: 19.9 ± 7.7 days; P = 0.001. and overall length of hospital stay (grade 1: 5 days vs. grade 2: 14.5 ± 5.0 days vs. grade 3: 63.4 ± 43.6 days; P = 0.025). There were no significant differences in PaO₂/FiO₂ ratio between groups at day 1. However, as expected, differences in PaO₂/FiO₂ ratio were found on day 3 (grade 1: 501 vs. grade 2: 424 ± 115 vs. grade 3: 318 ± 120; P = 0.049).

Conclusion

In this cohort of patients with major burns, the severity of inhalation injury was associated with prolonged MV, length of ICU stay, and overall length of hospital stay, as well as with deterioration in oxygenation on day 3.