These sounds have a longer duration than crackles and also have a musical quality. They are often detected more easily with forced expiration and are heard in patients with asthma or other obstructive diseases. In normal individuals the visceral and parietal pleura rub together silently during breathing. When the pleura are inflamed, coarse rubbing sounds can be heard during breathing. One can imitate these sounds by pushing the palm of the hand close to the ear and rubbing lightly and slowly over the dorsum of the hand.
Pleural rubs are close to the surface like they start at the end of the stethoscope.
They occur during both inspiration and expiration, generally at the end of inspiration and the beginning of expiration. All .wav lung sounds appear courtesy of the R.A.L.E Repository . The author would like to thank Dr. David Cugell, Northwestern University and the American College of Chest Physicians for providing these .au sounds. All rights reserved.