Respiratory sounds: Difference between revisions

| image = ThoracicLungs landmarksdiagram anterior view lung auscdetailed.svg

'''Respiratory sounds,''', also known as '''lung sounds''' or '''breath sounds,''', refer toare the specific sounds generated by the movement of air through the [[respiratory system ]].<ref>{{Cite web|title=Breath sounds: MedlinePlus Medical Encyclopedia|url=https://medlineplus.gov/ency/article/007535.htm|access-date=2021-11-11|website=medlineplus.gov|language=en}}</ref>. These may be easily audible or identified through [[auscultation]] of the [[respiratory system]] through the [[Respiratory examination|lung fields]] with a [[stethoscope]] as well as from the spectral characteristics of lung sounds.<ref>{{cite journal|last=Sengupta|first=Nandini|author2=Sahidullah, Md|author3=Saha, Goutam|title=Lung sound classification using cepstral-based statistical features|journal=Computers in Biology and Medicine|date=August 2016|volume=75|issue=1|pages=118–129|doi=10.1016/j.compbiomed.2016.05.013|pmid=27286184}}</ref> These include normal breath sounds and adventitious or "added" sounds such as [[crackles]], [[wheeze]]s, [[pleural friction rub]]s, [[stertor]], and [[stridor]].

Description 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 (≤200hz≤200&nbsp;Hz), medium or high (≥400hz≥400&nbsp;Hz)) and intensity (soft, medium, loud or very loud) of the sounds heard.<ref name=":102" />.

According to the ''Bates' Guide to Physical Examination and History-Taking 11th ed.,'' normalNormal breath sounds are classified as vesicular, bronchovesicular, bronchial or tracheal based on the anatomical location of auscultation.<ref name=":0">{{Cite book|last=Bickley|first=Lynn S|title=Bates' Guide to Physical Examination and History-Taking|publisher=Wolters Kluwer Health/Lippincott Williams & Wilkins|year=2013|isbn=978-1609137625|pages=311-312311–312|language=English}}</ref><ref name=":102">{{Citation|lastlast1=Zimmerman|firstfirst1=Barret|title=Lung Sounds|date=2021|url=http://www.ncbi.nlm.nih.gov/books/NBK537253/|work=StatPearls|place=Treasure Island (FL)|publisher=StatPearls Publishing|pmid=30725938|access-date=2021-11-11|last2=Williams|first2=Donna}}</ref>. Normal breath sounds can also be identified by patterns of sound duration and the quality of the sound as described in the table below:<ref name=":0" />

|expiratory sound duration is about equivalent to inspiratory sound

Common types of abnormal breath sounds include the following:<ref>{{Cite journal|title = Fundamentals of Lung Auscultation|last = Bohadana|first = Abraham|date = February 20, 2014|journal = New England Journal of Medicine|doi = 10.1056/NEJMra1302901|pmid = 24552321|volume=370|issue = 8|pages=744–751| s2cid=17871815 |url = https://uknowledge.uky.edu/cgi/viewcontent.cgi?article=1060&context=internalmedicine_facpub}}<!--https://uknowledge.uky.edu/cgi/viewcontent.cgi?article=1060&context=internalmedicine_facpub}}--></ref>

| whistling/sibilant, musical

| whistling/sibilant, musical

|[[epiglottitis]], foreign body, laryngeal [[oedema|edema]], [[croup]]

| [[Crackles]] (aka crepitations or rales)

| high (fine) or low (coarse), nonmusical

|nonmusical, many repeated rhythmic sounds

*Rales: Small clicking, bubbling, or rattling sounds in the lungs. They are heard when a person breathes in (inhales). They are believed to occur when air opens closed air spacesalveoli. Rales can bealso furtherbe described as moist, dry, fine, and coarse.<ref>{{Cite Thisweb term|title=Breath issounds: noMedlinePlus longerMedical muchEncyclopedia in|url=https://medlineplus.gov/ency/article/007535.htm use{{fact|access-date=November2022-05-30 2021|website=medlineplus.gov |language=en}}.</ref>

*Rhonchi are coarse rattling respiratory sounds, usually caused by secretions in bronchial airways. The sounds resemble snoring. "Rhonchi" is the plural form of the singular word "rhonchus". Since the mid-1990s, it has no longer been considered appropriate terminology in auscultation of the thorax, as much confusion has been reported in the published literature which confuses this with [[crackles|crepitations]] and [[wheezes]], so the exact nature of this term is unclear<ref>{{Cite journal|lastname=Wilkins|first=Robert L.|last2=Dexter|first2=James R.|last3=Murphy|first3=Raymond L. H.|last4=DelBono|first4=Elizabeth A.|date=1990-10-01|title=Lung Sound Nomenclature Survey|url=https:"Elsevier"//www.sciencedirect.com/science/article/pii/S0012369216344610|journal=Chest|language=en|volume=98|issue=4|pages=886–889|doi=10.1378/chest.98.4.886|issn=0012-3692}}</ref>.

*Stridor: Wheeze-like sound heard when a person breathes. Usually it is due to a blockage of airflow in the windpipe (trachea) or in the back of the throat.<ref>{{factCite web |title=Stridor: MedlinePlus Medical Encyclopedia |url=https://medlineplus.gov/ency/article/003074.htm |access-date=November2022-05-30 2021|website=medlineplus.gov |language=en}}.</ref>

[[File:Physical Exam - Stethoscope.jpg|thumb|A clinician auscultating the posterior lung of a patient.]][[Pectoriloquy]], [[egophony]] and [[bronchophony]] are tests of [[auscultation]] that utilize the phenomenon of [[vocal resonance]].<ref name=":02">{{Citation|last=Zimmerman|first=Barret|title=Lung Sounds|date=2021|url=http://www.ncbi.nlm.nih.gov/books/NBK537253/|work=StatPearls|place=Treasure Island (FL)|publisher=StatPearls Publishing|pmid=30725938|access-date=2021-11-11|last2=Williams|first2=Donna}}</ref>. Clinicians can utilize these tests during a physical exam to screen for pathological lung disease. For example, in [[whispered pectoriloquy]], the person being examined whispers - typically a two syllable number as the clinician listens over the [[Respiratory examination|lung fields]]. The whisper is not normally heard over the lungs, but if heard may be indicative of [[pulmonary consolidation]] in that area. This is because sound travels differently through denser (fluid or solid) media than the air that should normally be predominant in lung tissue. In egophony, the person being examined continually speaks the English long-sound "E" ([[Help:IPA/English|/i/]]). 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. This changes the sound produced, from a long "E" sound to a long "A" sound ([[Help:IPA/English|/eɪ/]]).

::Coarse crackles<ref>{{cite journal|last1=American Thoracic Society Ad Hoc Committee on Pulmonary Nomenclature|title=Updated nomenclature for membership reaction|journal=ATS News|date=1977|issue=3|pages=5–6}}</ref><ref>{{cite journal|last1=Loudon|first1=R|last2=Murphy|first2=R|title=Lung Sounds|journal=Am Rev Respir Dis|date=1984|volume=130|issue=4|pages=663–73|doi=10.1164/arrd.1984.130.4.663|doi-broken-date=31 October 20212024-09-12|pmid=6385790}}</ref>