。
She lost consciousness when she saw the accident scene.
Literal
She [topic-は] accident [possessive-の] scene [object-を] seeing, consciousness [object-を] lost.
現場 (げんば) is a versatile noun meaning 'the scene, the spot, the actual place where something happened' — used for accident scenes (事故現場), crime scenes (犯罪現場), construction sites (建設現場), and even in business for 'the front line' or 'on the ground.' 意識を失う ('lose consciousness') is the standard medical/clinical phrase, parallel to English. 失う is versatile across losing objects, people, and abstract states like consciousness.