What Is It, How Is It Assessed, Uses, and More
Author: Anna Hernández, MD
Illustrator: Aileen Lin
What is tactile fremitus?
Tactile fremitus, also known as tactile vocal fremitus, refers to the vibration of the chest wall that results from sound vibrations created by speech or other vocal sounds. When a person speaks, airflow from the lungs causes the vocal cords in the larynx to vibrate. These vibrations, which are also known as vocal fremitus, are transmitted down the tracheobronchial tree and through the lung tissue to the chest wall, where they can be felt by the hand as a palpable vibration.
Tactile fremitus is a clinical sign commonly assessed as part of a routine physical examination of the lungs. Respiratory physical examination generally consists of a visual assessment of the chest wall, palpation of chest expansion symmetry, tactile fremitus, percussion of the chest (which refers to the tapping of the thorax with the fingers), and lung auscultation (which uses a stethoscope to listen to an individual’s breathing sounds).In individuals with healthy lung tissue, tactile fremitus can be felt symmetrically along both sides of the chest. Normally, tactile fremitus is more pronounced near the clavicles and in between the shoulder blades, with a decreasing intensity towards the base of the lungs. Abrupt or asymmetrical changes in the intensity of tactile fremitus are considered to be an unusual finding, and may reflect the presence of an underlying lung condition.
How do you assess tactile fremitus?
Tactile fremitus is assessed by asking an individual to repeat a certain phrase while the examiner places the palms or the bony edge of their hands on the individual’s chest wall to feel for sound vibrations. Low-frequency vibrations, such as those created by two adjacent vowel sounds (e.g. “coin”, “sound”, or “boat”), are transmitted more effectively down the tracheobronchial tree, and thus evoke a more noticeable fremitus.
Examination of tactile fremitus is typically performed in all the major regions of the chest wall, covering the posterior, lateral and anterior chest. The examiner usually feels both sides of the chest wall at the same time to detect subtle changes between either side of the chest. Alternatively, one hand can be used to palpate one side of the chest and then moved back and forth to compare both sides.
What is tactile fremitus used for?
Changes in the intensity of tactile fremitus can be used to detect areas of unusual lung tissue density. The assessment of tactile fremitus is based on the principle that sound vibrations are conducted better through solid or fluid mediums, as opposed to air, which causes a decay in sound transmission. As a result, areas of increased lung tissue density are better conductors of sound, and generally present a more noticeable fremitus than normal air-filled lung tissue. Conversely, an excessive amount of air within the lungs may cause impaired sound transmission, leading to a decreased or absent tactile fremitus.
In combination with other clinical findings, tactile fremitus may be useful in suggesting an initial diagnosis that can then be confirmed by specific diagnostic tests. These tests may include blood tests, imaging techniques (chest x-ray, CT scan), or pulmonary function tests, depending on the potential clinical concern.
What causes decreased tactile fremitus?
Decreased intensity of tactile fremitus may occur as a result of excessive amounts of air in the lungs (also known as hyperinflation). Hyperinflation can be seen in individuals with pulmonary emphysema, chronic obstructive pulmonary disease (COPD), asthma, or severe airway obstruction.
Additionally, decreased or absent tactile fremitus may also occur when there is an increased distance between the lungs and the chest wall. For instance, excess fluid or air can collect in the pleural space; the thin fluid-filled cavity that forms between the two layers of serous membrane between the lungs and the chest wall. The buildup of excess fluid in the pleural space is known as a pleural effusion, whereas accumulation of air in the pleural space is known as a pneumothorax.Finally, tactile fremitus may also have decreased intensity in individuals with obesity or increased muscular mass, due to increased thickness of the chest wall.
What causes increased tactile fremitus?
Increased intensity of tactile fremitus generally occurs as a result of increased density within the lung tissue. This commonly occurs as a result of lung consolidation, which refers to the replacement of the air within healthy lung tissue with another substance; either inflammatory exudate, blood, pus, or cells. The most common cause of a consolidated lung is a lung infection, such as pneumonia. Other causes of increased tactile fremitus include partial or total collapse of a lung (known as atelectasis) or the presence of a solid mass in the lungs, such as a tumor.
What are the most important facts to know about tactile fremitus?
Tactile fremitus refers to the palpable vibration of the chest wall that results from the transmission of sound vibrations through the lung tissue to the chest wall. It is a clinical sign commonly assessed as part of routine physical examination of the lungs. Tactile fremitus can be assessed by asking an individual to repeat a certain phrase while the examiner palpates the individual’s chest wall to feel for vocal vibrations. Changes in the intensity of tactile fremitus can be used to detect areas of increased or decreased lung density. Tactile fremitus typically has a greater intensity in areas of increased lung density, such as a consolidated lung. Conversely, excess air within the lungs, or increased thickness of the chest wall, may lead to a decreased intensity of tactile fremitus.
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Resources for research and reference
McGee, S. R. (2018). Evidence-based Physical Diagnosis (4 edition). Philadelphia, PA: Elsevier
Riva, M. A., Domenici, G., Ceravolo, I., Cesana, G., & Castagna, F. (2017). At the origin of medical semeiotics: Charles J. B. Williams and tactile vocal fremitus. Internal and Emergency Medicine, 12(6): 901–902. DOI: 10.1007/s11739-017-1640-x
Seidel, H. M. (2011). Mosby's Guide to Physical Examination. St. Louis, Mo: Mosby/Elsevier