A Case of Nitrogen Dioxide-Induced Pulmonary Edema in Oxygen Torch

Abstract

Background: Welders tend to be exposed to a variety of hazards including metal fumes, toxic gases, electricity, heat, noise, and radiation such as ultraviolet and infrared light. Noxious gases generated during welding include carbon monoxide, ozone, and nitrogen oxide. Although the effects of metal fumes have been well studied, few reports have investigated the influence of noxious gas exposure in welders. Case report: We encountered a patient who developed non-cardiogenic pulmonary edema within a day after fairing up a steel plate with an oxygen/LPG torch. The patient was a 43-year-old female who complained of dyspnea which became exacerbated the following morning. Her chest X-ray and chest CT scan showed an extensive ground glass opacity which was more prominent in the both upper lungs. Both her symptoms and chest X-ray findings improved. We attributed the patient’s symptoms to non-cardiogenic pulmonary edema caused by nitrogen dioxide exposure, by reasoning that: 1) the patient's clinical course and radiologic findings suggested pulmonary edema 2) the event happened following fairing work with oxygen/LPG torch that usually induces a high concentration of nitrogen dioxide, and 3) the other possible causes of pulmonary edema could be excluded. Conclusion: Nitrogen dioxide-induced pulmonary edema should be considered in oxygen torch contrary to arc welding.