A wheeze is a continuous, coarse, whistling sound produced in the respiratory
airway
The respiratory tract is the subdivision of the respiratory system involved with the process of respiration in mammals. The respiratory tract is lined with respiratory epithelium as respiratory mucosa.
Air is breathed in through the nose to th ...
s during breathing. For wheezes to occur, some part of the respiratory tree must be narrowed or obstructed (for example narrowing of the lower respiratory tract in an asthmatic attack), or airflow velocity within the respiratory tree must be heightened. Wheezing is commonly experienced by persons with a
lung disease
The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of t ...
; the most common cause of recurrent wheezing is
asthma
Asthma is a long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wheezing, cou ...
, though it can also be a symptom of
lung cancer
Lung cancer, also known as lung carcinoma (since about 98–99% of all lung cancers are carcinomas), is a malignant lung tumor characterized by uncontrolled cell growth in tissue (biology), tissues of the lung. Lung carcinomas derive from tran ...
,
congestive heart failure
Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, a ...
, and certain types of
heart disease
Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels. CVD includes coronary artery diseases (CAD) such as angina and myocardial infarction (commonly known as a heart attack). Other CVDs include stroke, hea ...
s.
The
differential diagnosis
In healthcare, a differential diagnosis (abbreviated DDx) is a method of analysis of a patient's history and physical examination to arrive at the correct diagnosis. It involves distinguishing a particular disease or condition from others that p ...
of wheezing is wide, and the reason for wheezing in a given patient is determined by considering the characteristics of the wheezes and the historical and clinical findings made by the examining physician.
Characteristics
Wheeze
Wheezes occupy different portions of the
respiratory
The respiratory system (also respiratory apparatus, ventilatory system) is a biological system consisting of specific organs and structures used for gas exchange in animals and plants. The anatomy and physiology that make this happen varies grea ...
cycle depending on the site of airway obstruction and its nature. The fraction of the respiratory cycle during which a wheeze is produced roughly corresponds to the degree of airway obstruction.
Bronchiolar disease usually causes wheezing that occurs in the expiratory phase of respiration. As a rule, extrathoracic airway obstruction produce inspiratory sounds. Intrathoracic major airway obstruction produces inspiratory as well as expiratory sounds. Distal airway obstruction predominantly produces expiratory sounds.
The presence of expiratory phase wheezing signifies that the patient's
peak expiratory flow rate
The peak expiratory flow (PEF), also called peak expiratory flow rate (PEFR), is a person's maximum speed of expiration, as measured with a peak flow meter, a small, hand-held device used to monitor a person's ability to breathe out air. It measure ...
is less than 50% of normal. Wheezing heard in the inspiratory phase, on the other hand, is often a sign of a stiff stenosis, usually caused by
tumor
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...
s, foreign bodies or scarring. This is especially true if the wheeze is
monotonal, occurs throughout the inspiratory phase (i.e. is "holoinspiratory"), and is heard more proximally, in the
trachea
The trachea, also known as the windpipe, is a Cartilage, cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all air-breathing animals with lungs. The trachea extends ...
. Inspiratory wheezing also occurs in hypersensitivity pneumonitis. Wheezes heard at the end of both expiratory and inspiratory phases usually signify the periodic opening of deflated
alveoli Alveolus (; pl. alveoli, adj. alveolar) is a general anatomical term for a concave cavity or pit.
Uses in anatomy and zoology
* Pulmonary alveolus, an air sac in the lungs
** Alveolar cell or pneumocyte
** Alveolar duct
** Alveolar macrophage
* ...
, as occurs in some diseases that lead to collapse of parts of the
lung
The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of t ...
s.
The location of the wheeze can also be an important clue to the diagnosis. Diffuse processes that affect most parts of the lungs are more likely to produce wheezing that may be heard throughout the
chest
The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the crea ...
via a stethoscope. Localized processes, such as the occlusion of a portion of the respiratory tree, are more likely to produce wheezing at that location, hence the sound will be loudest and radiate outwardly. The pitch of a wheeze does not reliably predict the degree of narrowing in the affected airway.
Stridor
A special type of wheeze is
stridor
Stridor (Latin for "creaking or grating noise") 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 pha ...
. Stridor — the word is from the Latin, ''strīdor'' — is a harsh, high-pitched, vibrating sound that is heard in respiratory tract obstruction. Stridor heard solely in the inspiratory phase of respiration usually indicates an upper respiratory tract obstruction, "as with aspiration of a foreign body (such as the fabled pediatric peanut)."
Stridor in the inspiratory phase is usually heard with obstruction in the upper airways, such as the trachea, epiglottis, or larynx; because a block here means that no air may reach either lung, this condition is a medical emergency. Biphasic stridor (occurring during both the inspiratory and expiratory phases) indicates narrowing at the level of the
glottis
The glottis is the opening between the vocal folds (the rima glottidis). The glottis is crucial in producing vowels and voiced consonants.
Etymology
From Ancient Greek ''γλωττίς'' (glōttís), derived from ''γλῶττα'' (glôtta), va ...
or
subglottis
The subglottis or subglottic region is the lower portion of the larynx, extending from just beneath the vocal cords down to the top of the trachea. , the point between the upper and lower airways.
See also
*
Crackles
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. They are usually heard only with a stethoscope ("on auscultation"). Pulmonary crackles a ...
(also called "crepitations" or "rales")
*
Rhonchi
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. These may be easily audible or identified through auscultation of the respiratory system ...
*
Squawk (sound) Squawks, or short wheeze
A wheeze is a continuous, coarse, whistling sound produced in the respiratory airways during breathing. For wheezes to occur, some part of the respiratory tree must be narrowed or obstructed (for example narrowing of the ...
References
Further reading
*
External links
Audio Breath Sounds- Multiple case studies with audio files of lung sounds.
- sound files of breath sounds
{{Circulatory and respiratory system symptoms and signs
Symptoms and signs: Respiratory system