Vesicular - Normal
Vesicular - Diminished
Rhonchi - Low Pitched Wheezes
Crackles - Fine (Rales)
Crackles - Coarse (Rales)
Crackles - Early Inspiratory (Rales)
Crackles - Late Inspiratory (Rales)
Wheeze - Expiratory
Wheeze - Monophonic
Wheeze - Polyphonic
Vesicular breath sounds are soft and low pitched with a rustling quality during inspiration and are even softer during expiration. These are the most commonly auscultated breath sounds, normally heard over the most of the lung surface. They have an inspiration/expiratory ratio of 3 to 1 or I:E of 3:1.
Diminished vesicular sounds are of lower intensity and are less full or robust than vesicular sounds. These sounds can occur in patients who move a lowered volume of air, such as in frail, elderly patients or shallow breathing patients. They are also heard with obese or highly muscular patients, where tissue mass impedes sound. They exhibit a normal inspiration to expiration ratio of 3 to 1, or 4 to 1.
Bronchial breath sounds are hollow, tubular sounds that are lower pitched. They can be auscultated over the trachea where they are considered normal.
There is a distinct pause in the sound between inspiration and expiration. I:E ratio is 1:3 .
Inspiration to expiration periods are equal. These are normal sounds in the mid-chest area or in the posterior chest between the scapula. They reflect a mixture of the pitch of the bronchial breath sounds heard near the trachea and the alveoli with the vesicular sound. They have an I:E ratio of 1:1.
Low pitched wheezes (rhonchi) are continuous, both inspiratory and expiratory, low pitched adventitious lung sounds that are similar to wheezes. They often have a snoring, gurgling or rattle-like quality.
Rhonchi occur in the bronchi. Sounds defined as rhonchi are heard in the chest wall where bronchi occur, not over any alveoli. Rhonchi usually clear after coughing.
Fine crackles are brief, discontinuous, popping lung sounds that are high-pitched. Fine crackles are also similar to the sound of wood burning in a fireplace, or hook and loop fasteners being pulled apart or cellophane being crumpled.
Crackles, previously termed rales, can be heard in both phases of respiration. Early inspiratory and expiratory crackles are the hallmark of chronic bronchitis. Late inspiratory crackles may mean pneumonia, CHF, or atelectasis.
Coarse crackles are discontinuous, brief, popping lung sounds. Compared to fine crackles they are louder, lower in pitch and last longer. They have also been described as a bubbling sound. You can simulate this sound by rolling strands of hair between your fingers near your ear.
Early inspiratory crackles (rales), as suggested by the title, begin and end during the early part of inspiration. The pitch is lower than late inspiratory crackles. A patient's cough may decrease or clear these lung sounds. Early inspiratory crackles suggest decreased FEV1 capacity and are characteristic of COPD.
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.
Wheezes are adventitious lung sounds that are continuous with a musical quality. Wheezes can be high or low pitched. High pitched wheezes may have an auscultation sound similar to squeaking. Lower pitched wheezes have a snoring or moaning quality.
The proportion of the respiratory cycle occupied by the wheeze roughly corresponds to the degree of airway obstruction.
Wheezes are caused by narrowing of the airways.
Monophonic wheezes are loud, continuous sounds occurring in inspiration, expiration or throughout the respiratory cycle. The constant pitch of these sounds creates a musical tone. The tone is lower in pitch compared to other adventitious breath sounds. The single tone suggests the narrowing of a larger airway.
These lung sounds are heard over anterior, posterior and lateral chest walls. These sounds can be more intense over lung areas affected by partial obstructions.
Polyphonic wheezes are loud, musical and continuous. These breath sounds occur in expiration and inspiration and are heard over anterior, posterior and lateral chest walls. These sounds are associated with COPD and more severe asthma.
Stridor is caused by upper airway narrowing or obstruction. It is often heard without a stethoscope. It occurs in 10-20% of extubated patients.
Stridor is a loud, high-pitched crowing breath sound heard during inspiration but may also occur throughout the respiratory cycle most notably as a patient worsens.
In children, stridor may become louder in the supine position.
Causes of stridor are pertussis, croup, epiglottis, aspirations.
Vesicular breath sounds can be heard over most areas of lungs. Sound intensity can be higher when the stethoscope is positioned nearer to the bases and the periphery of the lung.
Diminished vesicular sounds can be heard over the anterior and posterior chest walls in obese or elderly patients.
This term would be used comparatively, auscultating from side to side.
Bronchial breath sounds are considered abnormal if heard over the peripheral lung fields.
Bronchial breath sounds other than close to the trachea may indicate pneumonia, atelectasis, pleural effusions.
These are abnormal in the lung periphery and may indicate an early infiltrate or partial atelectasis.
Intensity usually is higher over the large airways where bronchi exist.
Use the slider to reveal the area of the lungs where these sounds originate.
In this example, a patient has fine crackles. Such sounds are sometimes associated with congestive heart failure. During early to mid stages of CHF, fine crackles may be heard over the patient's posterior lung bases.
Use the slider to reveal the area of the lungs where these crackles originate.
In this example, a patient has chronic bronchitis. Course crackles are heard over most of the anterior and posterior chest walls.
Use the slider to reveal a depiction of the lungs where these course crackles originate.
This patient has chronic bronchitis. Early inspiratory crackles are heard over all chest walls.
Patients will have loud noisy mouth breathing as well.
Use the slider to reveal the locations where these crackles are heard.
In this example, a patient has late inspiratory fine crackles. Such sounds are sometimes associated with with interstitial fibrosis, pneumonia, CHF or atelectasis. These fine crackles may be heard over the posterior lung bases.
Use the slider to reveal the area of the lungs where these fine crackles originate.
In this case, expiratory wheezes are heard over most of the chest wall. This may indicate airflow obstruction, for example in patients with mild to moderate obstruction in asthma.
Note normal inspiratory breath sounds.
A fixed monophonic wheeze: same pitch, same place, may be an indication of foreign body aspiration or tumor.
Use the slider to reveal the lungs. In this patient, the wheezes are heard over most lung areas with greatest intensity in the highlighted region.
The higher the pitch, the longer the wheeze, the greater the obstruction.
Note the absence of any normal vesicular sounds.
Less than severe stridor can be auscultated over the larynx. Severe stridor can be heard without a stethoscope. Auscultation of lung sounds on the chest wall will be normal.