Characteristics of Breath Sounds Pitch of Intensity of Expiratory Locations Where Duration of Sounds Expiratory Sound Sound Heard Normally

Vesicular* Inspiratory sounds Soft Relatively low Over most of both last longer than lungs expiratory ones.

Broncho-vesicular Inspiratory and Intermediate Intermediate Often in the 1st and expiratory sounds 2nd interspaces are about equal. anteriorly and between the scapulae

Bronchial Expiratory sounds Loud Relatively high Over the manubrium, last longer than if heard at all inspiratory ones.

Tracheal Inspiratory and Very Loud Relatively high Over the trachea in expiratory sounds the neck are about equal. Adventitious Lung Sounds

DISCONTINUOUS SOUNDS ( OR RALES) are intermittent, nonmusical, and brief – like dots in time

Fine crackles (. . . . . ) are soft, high pitched, and very brief (5 – 10 msec).

Coarse crackles (• • • • • ) are somewhat louder, lower in pitch, and not quite so brief (20-30 msec).

CONTINUOUS SOUNDS are > 250 msec, notably longer than crackles – like dashes in time – but do not necessarily persist throughout the respiratory cycle. Unlike crackles, they are musical.

Wheezes ( ) are relatively high pitched (around 400 Hz or higher) and have a hissing or shrill quality.

Rhounchi ( ) are relatively low pitched (around 200 Hz or lower and have a quality. Physical Findings in Selected Chest Disorders

The black boxes in this table suggest a framework for clinical sessment. Start with the three boxes under Note: resonant, dull and hyperresonant. Then move from each of these to other boxes that emphasize some of the key differences among various conditions. The changes described vary with the extent and severity of the disorders. Abnormalities deep in the chest usually produce fewer signs at all. Use the table for the direction of atypical changes, not for absolute distinctions. Tactile Percussion Adventitious and Transmitted Condition Note Trachea Breath Sounds Sounds Voice Sounds

Normal Resonant Midline Vesicular, except perhaps None, except Normal The tracheobronchial tree and bronchovesicular and perhaps a few alveoli are clear; pleurae are bronchial sounds over the transient inspiratory thin and close together; large bronchi and trachea crackles at the mobility of the chest wall in respectively bases of the lungs unimpaired.

Resonant Midline Vesicular (normal) None; or scattered Normal Chronic coarse crackles in The bronchi are chronically early inspiration inflamed and a productive and perhaps is present. Airway expiration or obstruction may develop. or rhouchi

Left-Sided Heart Failure Resonant Midline Vesicular Late inspiratory Normal (Early) crackles in the Increased pressure in the dependent portions pulmonary veins causes of the lungs; congestion and interstitial possibly iwheezes edema (around the alveolu); bronchial mucosa may become edematous.

Consolidation Dull over the Bronchical over Late inspiratory Increased over the Alveoli fill with fluid or blood airless area Midline the involved area crackles over the involved area, with cells, as in penumonia, involved area bronchopony, or pulmonary egophony, and hemorrhage whispered Physical Findings in Selected Chest Disorders (cont’d)

Tactile Fremitus Condition Percussion Adventitious and Transmitted Note Trachea Breath Sounds Sounds Voice Sounds

Atelectasis (Lobar Obstruction) When a plug in a Dull over the May be shifted Usually absent when None Usually absent mainstem bronchus (as airless area toward bronchial plug persists. when the bronchial from mucus or a foreign involved side Exceptions include right plug persists. In object) obstructs air upper lobe atelectasis, exceptions, e.g., flow, affected lung where adjacent tracheal right upper lobe tissue collapses into an sounds may be atelectasis, may be airless state. transmitted. increased

Pleural Effusion Fluid accumulates in the Decreased to absent, but None, except a Decreased to pleural space, separates Dull to flat over Shifted toward bronchial breath sounds possible pleural rub absent, but may be airfilled lung from the the fluid opposite side in may be heard near top of increased towards chest wall, blocking the a large effusion large effusion the top of a large transmission of sound. effusion.

Pneumothorax Decreased to absent over None, except a Decreased to When air leaks into the Hyperresonanat Shifted toward the pleural air possible pleural rub absent over the pleural space, usually Or tympanitic opposite side if pleural air unilaterally, the lung over the pleural much air recoils from the chest air wall. Pleural blocks transmission of sound. Physical Findings in Selected Chest Disorders (cont’d)

Tactile Fremitus Percussion Adventitious and Transmitted Condition Note Trachea Breath Sounds Sounds Voice Sounds

Chronic Obstructive Diffusely Midline Decreased to absent None, or the Decreased Pulmonary Disease Hyperresonant crackles, wheezes, (COPD) and ronchi of Slowly progressive associated chronic disorder in which the bronchitis distal air spaces enlarge and lungs become hyperinflated. Chronic bronchitis is often associated.

Asthma Widespread narrowing Resonant to Midline Often obscured by Wheezes, possibly Decreased of the tracheobronchial diffusely wheezes crackles tree diminishes airflow hyperresonant to a fluctuating degree. During attacks, airflow decreases further and lungs hyperinflate. Normal and Altered Breath and Voice Sound

The origins of breath sounds are still unclear. According to leading theories, turbulent air flow in the central airways produces the tracheal and bronchial breath sounds. As these sounds pass through the lungs to the periphery, lung tissue filters out their higher-pitched components and only the soft and lower-pitched components reach the chest wall, where they are heard as vesicular breath sounds. Noramlly, tracheal and bronchial sounds may be heard over the trachea and mainstem bronchi; vesicular breath sounds predominate throughout most of the lungs. When lung tissue loses its air, it transmits high-pitched sounds much better. If the tracheobronchial tree is open, bronchial breath sounds may replace the normal vesicular sounds over airless areas of the lung. This change is seen in lober when the alveoli fill with fluid, red cells, and white cells – a process calles consolidation. Other causes include pulmonary edema or hemorrhage. Bronchial breath sounds usually correlate with an increase in tactile fremitus and transmitted voice sounds. These findings are summarized below.

Normal Air-Filled Lung Airless Lung, as in Lobar Pneumonia

Breath Sounds Predominantly vesicular Bronchial or bronchovesicular over the involved area

Transmitted Voice Sounds Spoken words muffled and indistinct Spoken words louder, clearer () Spoken “ee” heards as “ee” Spoken “ee” heard as “ay” (egophony) Whispered words faint and indistinct, if heard at Whispered words louder, clearer () Tactile Fremitus all Increased Normal Abnormalities in Rate and Rhythm of When observing respiratory patterns, think in terms of rate, depth, and regularity of the patient’s breathing. Describe what you see in these terms. Traditional terms, such as , are given below so that you will understand them, but simple descriptions are recommended for use.

Rapid Deep Breathing Rapid (, Hypeventilation) Slow Breathing () Normal (Tachypnea) The respiratory rate is about Rapid shallow breathing has a Rapid deep breathing has several Slow breathing may be secondary 14-20 per min in normal adults number of causes, including causes, including exercise, anxiety, to such causes as diabetic coma, and up to 44 per min in restrictive lung disease, pleuritic and metabolic acidoses. In the drug induced respiratory infants. , and an elevated comatose patient, consider infarction, depression, and increased diaphragm. hypoxia, or phypoglycemia affecting intracranial pressure. the midbrain or pons. is deep breathing due to metabolic acidosis. It may be fast, normal in rate, or slow.

Ataxic Breathing Cheyne-Strokes Breathing (Biot’s Breathing) Sighing Respiration Obstructive Breathing Ataxic breathing is Breathing punctuated by frequent In obstructive lung disease, Periods of deep breathing characterized by unpredicted sighs should alert you to the expiration is prolonged because alternate with periods of irregularity. Breaths may be possibility of narrowed airways increase the (no breathing). Children and shallow or deep, and stop for syndrome – a common cause of resistance to airflow. Causes aging people normally may short periods. Causes include dyspnea and dizziness. Occasional include , chronic show this pattern in sleep. respiratory depression and brain sighs are normal. bronchitis, and COPD. Other causes include heart damage, typically at the failure, uremia, drug-induced medullary level. respiratory depression, and brain damage (typically on both sides of the cerebral hemispheres or diencephalon.