This article discusses a case report of a patient with Legionella pneumophila pneumonia who underwent endoscopic surgery. The patient had respiratory distress and was at risk for postoperative pulmonary complications. To avoid these complications, the patient was treated with noninvasive respiratory support using high-flow nasal cannula (HFNC) oxygen therapy. The HFNC therapy allowed for adequate oxygenation and ventilation during the procedure, and the patient had a successful outcome. The use of HFNC in endoscopic procedures may be a beneficial alternative to invasive ventilation methods. [Extracted from the article]