Humanity and love are the only saving grace in this materialistic world governed by hatred and chaos. Our lives should be centered on harbouring these feelings in ourselves and in those around us.
Keeping this in mind, if a doctor gets an opportunity to save a distressed and wounded person, he should definitely help him. People consider doctors next to God. Even their profession asks them to help all patients, regardless of caste, race, religion or nationality. Thus, keeping humanity superior to anything else in life, the war prisoner should definitely be saved.