Usefulness of technetium-99m hexamethylpropylene amine oxime lung scan to detect inhalation lung injury of patients with pulmonary symptoms/signs but negative chest radiograph and pulmonary function test findings after a fire accident--a preliminary report.

OBJECTIVE In this study, we employed technetium-99m hexamethylpropylene amine oxime (99mTc HMPAO) lung scan to detect inhalation lung injury of patients after a fire accident. METHODS Ten healthy men for controls and 10 male patients with pulmonary symptoms/signs from a fire accident were enrolled in this study for comparison. 99mTc HMPAO lung scan was performed in each control and patient, as well as the degree of pulmonary vascular endothelium damage was represented as lung/liver uptake ratios (L/L ratio). All of the controls and patients had no smoking histories. None of the controls and patients had positive findings of plain chest radiograph (CXR) and pulmonary function test (PFT). RESULTS The results showed that significantly higher L/L ratio in the 10 patients (0.53 +/- 0.07) than in the 10 controls (0.30 +/- 0.07) (the p value < 0.05). Using a cut-off value of 0.40, all of the 10 patients had abnormally increased L/L ratios. CONCLUSIONS We conclude that 99mTc HMPAO lung scan has the potential to be a sensitive, objective and noninvasive method to detect inhalation lung injury of patients with pulmonary symptoms/signs but negative CXR and PFT findings after a fire accident.