In 1976, the International Lung Sound Association simplified the sub-categories as follows: Those categories were 'Continuous' and 'Interrupted' (or non-continuous).

In 1957, Robertson and Coope proposed the two main categories of adventitious (added) lung sounds. This changes the sound produced, from a long 'E' sound to a long 'A' sound ( /eɪ/). The lungs are usually air filled, but if there is an abnormal solid component due to infection, fluid, or tumor, the higher frequencies of the 'E' sound will be diminished. In egophony, the person being examined continually speaks the English long-sound 'E' ( /i/). This is because sound travels differently through denser (fluid or solid) media than the air that should normally be predominant in lung tissue. The whisper is not normally heard over the lungs, but if heard may be indicative of pulmonary consolidation in that area. For example, in whispered pectoriloquy, the person being examined whispers a two syllable number as the clinician listens over the lung fields. Clinicians can utilize these tests during a physical exam to screen for pathological lung disease. Pectoriloquy, egophony and bronchophony are tests of auscultation that utilize the phenomenon of vocal resonance. Ī clinician auscultating the posterior lung of a patient. Wheezing and other abnormal sounds can sometimes be heard without a stethoscope. They are most often heard when a person breathes out (exhales). Wheezing: High-pitched sounds produced by narrowed airways.Usually it is due to a blockage of airflow in the windpipe (trachea) or in the back of the throat. Stridor: Wheeze-like sound heard when a person breathes.'Rhonchi' is the plural form of the singular word 'rhonchus'. Rhonchi are coarse rattling respiratory sounds, usually caused by secretions in bronchial airways.Rales can also be described as moist, dry, fine, and coarse. They are believed to occur when air opens alveoli. They are heard when a person breathes inhales. Rales: Small clicking, bubbling, or rattling sounds in the lungs.Surfactant deficiency, pneumonia, cardiac abnormalities Inflammation of lung linings, lung tumors Problems playing this file? See media help. Normal breath sounds can also be identified by patterns of sound duration and the quality of the sound as described in the table below: NameĮxpiratory sound duration is equivalent to inspiratory soundĮxpiratory sound duration is longer than inspiratory soundĪnteriorly between the 1st and 2nd intercostal space Įxpiratory sound duration is about equivalent to inspiratory soundĮxpiratory sound duration is shorter than inspiratory soundĬommon types of abnormal breath sounds include the following: NameĬaused by narrowing of airways, such as in asthma, chronic obstructive pulmonary disease, foreign body. Normal breath sounds are classified as vesicular, bronchovesicular, bronchial or tracheal based on the anatomical location of auscultation. These include normal breath sounds and adventitious or 'added' sounds such as crackles, wheezes, pleural friction rubs, stertor, and stridor.ĭescription and classification of the sounds usually involve auscultation of the inspiratory and expiratory phases of the breath cycle, noting both the pitch (typically described as low (≤200 Hz), medium or high (≥400 Hz)) and intensity (soft, medium, loud or very loud) of the sounds heard. These may be easily audible or identified through auscultation of the respiratory system through the lung fields with a stethoscope as well as from the spectral characteristics of lung sounds. Respiratory sounds, also known as lung sounds or breath sounds, refer to the specific sounds generated by the movement of air through the respiratory system.

Adventitious breath sounds rales