Respiratory sounds

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Respiratory sounds
Other namesBreath sounds, lung sounds
Lungs diagram detailed.svg
Specialty Respirology

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. [1] 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. [2] These include normal breath sounds and adventitious or "added" sounds such as crackles, wheezes, pleural friction rubs, stertor, and stridor.

Contents

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 (≤200 Hz), medium or high (≥400 Hz)) and intensity (soft, medium, loud or very loud) of the sounds heard. [3]

Normal breath sounds

Normal breath sounds are classified as vesicular, bronchovesicular, bronchial or tracheal based on the anatomical location of auscultation. [4] [3] Normal breath sounds can also be identified by patterns of sound duration and the quality of the sound as described in the table below: [4]

NameLocation where heard normallyQuality of soundSound durationExample
trachealover the trachea very loudexpiratory sound duration is equivalent to inspiratory sound
bronchialover the manubrium loud, high pitchedexpiratory sound duration is longer than inspiratory sound
bronchovesicularanteriorly between the 1st and 2nd intercostal space;

posteriorly in-between the scapulae

intermediateexpiratory sound duration is about equivalent to inspiratory sound
vesicularover most of both lungssoft, low pitchedexpiratory sound duration is shorter than inspiratory sound

Abnormal breath sounds

Common types of abnormal breath sounds include the following: [5]

NameContinuous/discontinuousFrequency/pitchInspiratory/expiratoryQualityCommon CausesExample
Wheeze or rhonchi continuoushigh (wheeze) or lower (rhonchi)expiratory or inspiratorywhistling/sibilantCaused by narrowing of airways, such as in asthma, chronic obstructive pulmonary disease, foreign body.
Stridor continuoushighinspiratory, expiratory, or both [6] whistling/sibilant epiglottitis, foreign body, laryngeal edema, croup
Inspiratory gasp continuoushighinspiratorywhoop pertussis (whooping cough)see New England Journal of Medicine, Classic Whooping Cough sound file, Supplement to the N Engl J Med 2004; 350:2023-2026
Crackles (rales)continuoushigh (fine) or low (coarse)inspiratorycracking/clicking/rattling [7] pneumonia, pulmonary edema, tuberculosis, bronchitis, heart failure
Pleural friction rub discontinuouslowinspiratory and expiratorymany repeated rhythmic soundsinflammation of lung linings, lung tumorsnot available
Hamman's sign (or Mediastinal crunch)discontinuousneither (heartbeat)crunching, rasping pneumomediastinum, pneumopericardium not available
GruntingContinuouslowexpiratorysnoringsurfactant deficiency, pneumonia, cardiac abnormalities [8]

Continued

Other tests of auscultation

A clinician auscultating the posterior lung of a patient. Physical Exam - Stethoscope.jpg
A clinician auscultating the posterior lung of a patient.

Pectoriloquy, egophony and bronchophony are tests of auscultation that utilize the phenomenon of vocal resonance. [3] 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 a two syllable number as the clinician listens over the 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" (/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 (/eɪ/).

History

In 1957, Robertson and Coope proposed the two main categories of adventitious (added) lung sounds. Those categories were "Continuous" and "Interrupted" (or non-continuous). [12] In 1976, the International Lung Sound Association simplified the sub-categories as follows:

Continuous
Wheezes (>400 Hz)
Rhonchi (<200 Hz)
Discontinuous
Fine crackles
Coarse crackles [13] [14]

Several sources will also refer to "medium" crackles, as a crackling sound that seems to fall between the coarse and fine crackles. Crackles are defined as discrete sounds that last less than 250 ms, while the continuous sounds (rhonchi and wheezes) last approximately 250 ms. Rhonchi are usually caused by a stricture or blockage in the upper airway. These are different from stridor.

See also

Related Research Articles

<span class="mw-page-title-main">Stethoscope</span> Medical device for auscultation

The stethoscope is a medical device for auscultation, or listening to internal sounds of an animal or human body. It typically has a small disc-shaped resonator that is placed against the skin, with either one or two tubes connected to two earpieces. A stethoscope can be used to listen to the sounds made by the heart, lungs or intestines, as well as blood flow in arteries and veins. In combination with a manual sphygmomanometer, it is commonly used when measuring blood pressure.

Tracheomalacia is a condition or incident where the cartilage that keeps the airway (trachea) open is soft such that the trachea partly collapses especially during increased airflow. This condition is most commonly seen in infants and young children. The usual symptom is stridor when a person breathes out. This is usually known as a collapsed windpipe.

<span class="mw-page-title-main">Heart murmur</span> Medical condition

Heart murmurs are unique heart sounds produced when blood flows across a heart valve or blood vessel. This occurs when turbulent blood flow creates a sound loud enough to hear with a stethoscope. Turbulent blood flow is not smooth. The sound differs from normal heart sounds by their characteristics. For example, heart murmurs may have a distinct pitch, duration and timing. The major way health care providers examine the heart on physical exam is heart auscultation; another clinical technique is palpation, which can detect by touch when such turbulence causes the vibrations called cardiac thrill. A murmur is a sign found during the cardiac exam. Murmurs are of various types and are important in the detection of cardiac and valvular pathologies.

<span class="mw-page-title-main">Acute bronchitis</span> Medical condition

Acute bronchitis, also known as a chest cold, is short-term bronchitis – inflammation of the bronchi of the lungs. The most common symptom is a cough. Other symptoms include coughing up mucus, wheezing, shortness of breath, fever, and chest discomfort. The infection may last from a few to ten days. The cough may persist for several weeks afterward with the total duration of symptoms usually around three weeks. Some have symptoms for up to six weeks.

<span class="mw-page-title-main">Pulmonary heart disease</span> Medical condition

Pulmonary heart disease, also known as cor pulmonale, is the enlargement and failure of the right ventricle of the heart as a response to increased vascular resistance or high blood pressure in the lungs.

Crackles are the clicking, rattling, or crackling noises that may be made by one or both lungs of a human with a respiratory disease during inhalation, and occasionally during exhalation. They are usually heard only with a stethoscope. Pulmonary crackles are abnormal breath sounds that were formerly referred to as rales.

<span class="mw-page-title-main">Auscultation</span> Listening to the internal sounds of the body, usually using a stethoscope

Auscultation is listening to the internal sounds of the body, usually using a stethoscope. Auscultation is performed for the purposes of examining the circulatory and respiratory systems, as well as the alimentary canal.

<span class="mw-page-title-main">Pulmonology</span> Study of respiratory diseases

Pulmonology, pneumology or pneumonology is a medical specialty that deals with diseases involving the respiratory tract. It is also known as respirology, respiratory medicine, or chest medicine in some countries and areas.

<span class="mw-page-title-main">Superior vena cava syndrome</span> Group of symptoms caused by obstruction of the superior vena cava

Superior vena cava syndrome (SVCS), is a group of symptoms caused by obstruction of the superior vena cava ("SVC"), a short, wide vessel carrying circulating blood into the heart. The majority of cases are caused by malignant tumors within the mediastinum, most commonly lung cancer and non-Hodgkin's lymphoma, directly compressing or invading the SVC wall. Non-malignant causes are increasing in prevalence due to expanding use of intravascular devices, which can result in thrombosis. Other non-malignant causes include benign mediastinal tumors, aortic aneurysm, infections, and fibrosing mediastinitis.

Stridor is a high-pitched extra-thoracic breath sound resulting from turbulent air flow in the larynx or lower in the bronchial tree. It is different from a stertor which is a noise originating in the pharynx.

A wheeze is a clinical symptom of a continuous, coarse, whistling sound produced in the respiratory airways during breathing. For wheezes to occur, part of the respiratory tree must be narrowed or obstructed, or airflow velocity within the respiratory tree must be heightened. Wheezing is commonly experienced by persons with a lung disease; the most common cause of recurrent wheezing is asthma, though it can also be a symptom of lung cancer, congestive heart failure, and certain types of heart diseases.

<span class="mw-page-title-main">Respiratory examination</span> Inspection conducted as part of a physical

A respiratory examination, or lung examination, is performed as part of a physical examination, in response to respiratory symptoms such as shortness of breath, cough, or chest pain, and is often carried out with a cardiac examination.

<span class="mw-page-title-main">Respiratory disease</span> Disease of the respiratory system

Respiratory diseases, or lung diseases, are pathological conditions affecting the organs and tissues that make gas exchange difficult in air-breathing animals. They include conditions of the respiratory tract including the trachea, bronchi, bronchioles, alveoli, pleurae, pleural cavity, the nerves and muscles of respiration. Respiratory diseases range from mild and self-limiting, such as the common cold, influenza, and pharyngitis to life-threatening diseases such as bacterial pneumonia, pulmonary embolism, tuberculosis, acute asthma, lung cancer, and severe acute respiratory syndromes, such as COVID-19. Respiratory diseases can be classified in many different ways, including by the organ or tissue involved, by the type and pattern of associated signs and symptoms, or by the cause of the disease.

Acute severe asthma, also known as status asthmaticus, is an acute exacerbation of asthma that does not respond to standard treatments of bronchodilators (inhalers) and corticosteroids. Asthma is caused by multiple genes, some having protective effect, with each gene having its own tendency to be influenced by the environment although a genetic link leading to acute severe asthma is still unknown. Symptoms include chest tightness, rapidly progressive dyspnea, dry cough, use of accessory respiratory muscles, fast and/or labored breathing, and extreme wheezing. It is a life-threatening episode of airway obstruction and is considered a medical emergency. Complications include cardiac and/or respiratory arrest. The increasing prevalence of atopy and asthma remains unexplained but may be due to infection with respiratory viruses.

<span class="mw-page-title-main">Pulmonary consolidation</span> Medical condition

A pulmonary consolidation is a region of normally compressible lung tissue that has filled with liquid instead of air. The condition is marked by induration of a normally aerated lung. It is considered a radiologic sign. Consolidation occurs through accumulation of inflammatory cellular exudate in the alveoli and adjoining ducts. The liquid can be pulmonary edema, inflammatory exudate, pus, inhaled water, or blood. Consolidation must be present to diagnose pneumonia: the signs of lobar pneumonia are characteristic and clinically referred to as consolidation.

Egophony is an increased resonance of voice sounds heard when auscultating the lungs, often caused by lung consolidation and fibrosis. It is due to enhanced transmission of high-frequency sound across fluid, such as in abnormal lung tissue, with lower frequencies filtered out. It results in a high-pitched nasal or bleating quality in the affected person's voice.

Whispered pectoriloquy refers to an increased loudness of whispering noted during auscultation with a stethoscope on the lung fields on a patient's torso.

<span class="mw-page-title-main">Bronchophony</span> Medical condition

Bronchophony is the abnormal transmission of sounds from the lungs or bronchi. Bronchophony is a type of pectoriloquy.

Rheumatoid lung disease is a disease of the lung associated with RA, rheumatoid arthritis. Rheumatoid lung disease is characterized by pleural effusion, pulmonary fibrosis, lung nodules and pulmonary hypertension. Common symptoms associated with the disease include shortness of breath, cough, chest pain and fever. It is estimated that about one quarter of people with rheumatoid arthritis develop this disease, which are more likely to develop among elderly men with a history of smoking.

Mineral dust airway disease is a general term used to describe complications due to inhaled mineral dust causing fibrosis and narrowing of primarily the respiratory bronchioles. It is a part of a group of disorders known as pneumoconioses which is characterized by inhaled mineral dust and the effects on the lungs.

References

  1. "Breath sounds: MedlinePlus Medical Encyclopedia". medlineplus.gov. Retrieved 2021-11-11.
  2. Sengupta, Nandini; Sahidullah, Md; Saha, Goutam (August 2016). "Lung sound classification using cepstral-based statistical features". Computers in Biology and Medicine. 75 (1): 118–129. doi:10.1016/j.compbiomed.2016.05.013. PMID   27286184.
  3. 1 2 3 Zimmerman, Barret; Williams, Donna (2021), "Lung Sounds", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID   30725938 , retrieved 2021-11-11
  4. 1 2 Bickley, Lynn S (2013). Bates' Guide to Physical Examination and History-Taking. Wolters Kluwer Health/Lippincott Williams & Wilkins. pp. 311–312. ISBN   978-1609137625.
  5. Bohadana, Abraham (February 20, 2014). "Fundamentals of Lung Auscultation". New England Journal of Medicine. 370 (8): 744–751. doi:10.1056/NEJMra1302901. PMID   24552321. S2CID   17871815.
  6. Leung, Alexander K. C.; Cho, Helen (1999-11-15). "Diagnosis of Stridor in Children". American Family Physician. 60 (8): 2289–2296. ISSN   0002-838X. PMID   10593320.
  7. "Breath sounds: MedlinePlus Medical Encyclopedia". medlineplus.gov. Retrieved 2022-05-06.
  8. 1 2 McGann, Kathleen A.; Long, Sarah S. (2018-01-01), Long, Sarah S.; Prober, Charles G.; Fischer, Marc (eds.), "21 - Respiratory Tract Symptom Complexes", Principles and Practice of Pediatric Infectious Diseases (Fifth Edition), Elsevier, pp. 164–172.e2, ISBN   978-0-323-40181-4 , retrieved 2022-05-06
  9. "Breath sounds: MedlinePlus Medical Encyclopedia". medlineplus.gov. Retrieved 2022-05-30.
  10. "Stridor: MedlinePlus Medical Encyclopedia". medlineplus.gov. Retrieved 2022-05-30.
  11. "Breath sounds: Medline Plus". NIH. Retrieved 5 May 2015.
  12. Robertson, A (1957). "Rales, rhonchi, and Laennec". Lancet. 2 (6992): 417–23. doi:10.1016/S0140-6736(57)92359-0. PMID   13464086.
  13. American Thoracic Society Ad Hoc Committee on Pulmonary Nomenclature (1977). "Updated nomenclature for membership reaction". ATS News (3): 5–6.
  14. Loudon, R; Murphy, R (1984). "Lung Sounds". Am Rev Respir Dis. 130 (4): 663–73. doi:10.1164/arrd.1984.130.4.663 (inactive 31 January 2024). PMID   6385790.{{cite journal}}: CS1 maint: DOI inactive as of January 2024 (link)

Mansy, H. A.; Royston, T. J.; Balk, R. A.; Sandler, R. H. (2002). "Pneumothorax detection using computerised analysis of breath sounds". Medical & Biological Engineering & Computing. 40 (5): 526–532. doi:10.1007/BF02345450. PMID   12452412. S2CID   7413897.