Inhalation injury severity scoring system: a quantitative method.

Abstract

Inhalation injury, a major contributor to burn-related mortality, has been difficult to quantify. A scoring system paralleling current adult respiratory distress syndrome systems has the potential to distinguish survivors from nonsurvivors. The utility of the PaO2/FiO2 (P/F) ratio in predicting injury severity was first examined. In a review of 120 patients with inhalation injury, those with P/F ratios greater than or equal to 300 after resuscitation were more likely to survive than those with ratios less than 300. The P/F ratio had no value when obtained before resuscitation. Next, a scoring system was developed to assist in comparing the severity of injury in ventilator-dependent patients with burns. Measurements were recorded prospectively in four categories: chest x-ray evaluation, P/F ratio, peak inspiratory pressure, and bronchoscopy. When comparing survivors (20) versus nonsurvivors (6), significant differences were found early (day 0, day 1, and week 1) for P/F ratio and overall severity score. Differences were seen later (week 1 and week 2) for chest x-ray evaluation and peak inspiratory pressure values. Because of low numbers the value of bronchoscopy could not be evaluated. The role of an inhalation injury severity scoring system for predicting survival should be examined in larger prospective trials.