What is pleural friction rub and where is it heard?
Pleural rubs occur when two inflamed pleural surfaces rub against each other during respiration. This is often heard in pleurisy, or inflammation of the tissues that lie in the lungs and chest cavity. The sound may be continuous or broken and creaking or grating. It can be described as the sound of walking on fresh snow or rubbing leather together and is most commonly heard in the base of the lungs.