For heart sounds listen to the synthetic sound while reviewing this lesson.
Late inspiratory crackles (rales) begin in late inspiration and increase in intensity. They are normally higher pitched and can vary in loudness. These adventitious breath sounds resemble the noise made when hook and loop fasteners are being separated. These sounds are heard over posterior bases of the lungs. They may clear with changes in posture or several deep breaths. They do not clear with coughing.