Lung exam

 

Inspection

Start with the patient’s general appearance – do they look sick or well? Is their breathing comfortable or labored? If labored, are they using accessory muscles to help their breathing?  Are they breathing through pursed lips? Patients may also find that a tripod position (leaning forward with elbows on thighs) helps with breathing, thought to be due to improved use of accessory muscles (particularly the rib cage muscles) in that position. Over time they may develop rough patches or calluses above their knees, termed Dahl’s sign. How are their teeth?  Poor dentition and gingivitis can support the growth of oral anaerobic bacteria. Do they have Horner’s syndrome? The triad of ptosis, meiosis and anhidrosis can be seen with superior sulcus tumors of the lung (ie, pancoast tumors) from compression of the sympathetic ganglion. Do they have redness and swelling of their face, with engorged veins on their chest? This can be seen in SVC syndrome from lung tumors or infections, or these days from intravenous catheters that have become obstructed (catheters for dialysis or chemo or antibiotics). What is the movement of their abdomen when they are breathing? Normally when we inhale, our chest and abdomen both move outwards, as the diaphragm pushes downwards and the ribs are moved upwards. In severe neuromuscular disease, patients may develop what is termed paradoxical breathing, or abdominal paradox, where the abdomen moves inwards on inspiration, due to a weak or paralyzed diaphragm. This is a sign of impending respiratory failure in an unstable patient.

Can you hear any audible breath sounds from across the room? How is the patient’s color, including their lips and digits? Do they have a bluish hue of cyanosis, or a yellow-brown discoloration from chronic tobacco use? Do they have clubbing of their digits? Do you see any signs of chronic corticosteroid use, such as thinning or bruising of the skin, or redistribution of fat to their trunks and face? These are Cushingoid features, signs of Cushing’s syndrome, from excess corticosteroids, frequently given for chronic obstructive pulmonary disease.

 

Palpation

Palpation of the chest may reveal areas of pain, rattling, or wheezing from secretion or airway obstruction, or the characteristic popping from subcutaneous emphysema (air tracking under the skin from rupture of an air filled structure).

• Asymmetry of chest wall expansion can be assessed by placing the hands on the thorax on either side of the midline and observing how they move with inhalation. Normally the chest wall will expand evenly with inspiration. You may note asymmetric expansion if the patient has pneumonia, pleural effusion, collapsed lung, or other abnormality.

 

Tactile Fremitus

• This is the palpable vibrations felt on the chest when patients speak. Find what part of your hand is most sensitive to vibrations – often it is the portion of your hand that is most ticklish when you lightly stroke one palm with the other hand’s fingertips – and place this on the patient’s thorax. Have the patient say “toy boat” or “ninety-nine” over and over as you feel for asymmetry. You may find one hand works better than the other, and you will need to switch from side to side at the same level. You are assessing for asymmetry. If you feel asymmetry, it may be abnormally decreased on one side or increased on the other.
  • Decreased fremitus may be due to fluid (effusions) or air (pneumothorax) between the lung and chest wall (the extra interface causes some sounds to be reflected rather than transmitted), or increased air (lower density) in the lungs (COPD).
  • Increased fremitus is felt in pneumonia, as the sound waves travel better through consolidated lung than air filled lung. However, if the bronchial tubes are blocked, you may not feel increased fremitus (or hear bronchial breath sounds or vocal resonance).
  • What about masses? Not much is known about how sound travels through a lung mass, but most are smaller than a pneumonia or pleural effusion, and patients with masses rarely present with shortness of breath, which is where this examination is most useful.

 

 

Percussion

Percussion is the practice of tapping a finger that is placed firmly upon the patient’s thorax in order to hear and feel asymmetry. Usually the middle finger of the non-dominant hand is placed firmly upon the thorax, and the middle finger of the dominant hand is used to tap firmly and rapidly upon the middle phalanx or distal phalangeal joint of the non-dominant hand. As with palpation and auscultation, one should compare each side of the thorax, moving from side to side, scanning for differences. It may take some practice to be able to generate an audible tone, not a dampened one – to practice, try tapping out studs on a wall, or try tapping a wine glass so it rings. A number of tones can be detected with percussion (both heard and felt by the finger which is being tapped, known as the pleximeter finger). The five below are the most commonly used

• Flat
  • The tone/sensation felt when you percuss the thigh
• Dull
  • Found when percussing over the liver
• Resonant
  • Found over normal lung
• Hyperresonant
  • Found over emphysematous lungs
• Tympanic
  • Found over a pneumothorax (similar to the tone over the gastric air bubble)

The key point is normal lung should sound resonant, although you may detect dullness over the scapulae and over the heart. If you hear or feel something other than resonance when percussing the thorax, and if it is asymmetric, you should suspect some pathology is present.

 

Auscultation

Often you may hear crackles in patients that have no evidence of pulmonary disease on chest x-rays or CT scans, especially in cases of chronic congestive heart failure. There are a number of different sounds that can be heard when listening to the lungs, and they can be divided into basic and adventitious (or extra) lung sounds. The two basic lung sounds are made as air moves in and out of the airways and are called vesicular (normal) breath sounds and bronchial (tubular) breath sounds. All patients will have one or both of these basic lung sounds when they breathe.

 

 

Breath Sounds

Vesicular breath sounds

• Vesicular breath sounds are what one hears when listening over normal, healthy lungs. The inspiratory phase is louder and longer (about a 3:1 ratio) than the expiratory phase, and there is no gap between the two phases.

 

 

Bronchial (tubular) breath sounds

• Bronchial (ie, tubular) breath sounds are loud in both inhalation and exhalation, and have a tubular quality – imagine the sound of Darth Vader breathing. There may be a gap between inhalation and exhalation. Listening over the trachea mimics bronchial breath sounds.
• Bronchial breath sounds are heard over areas of consolidated lung
• Bronchial breath sounds may also be heard over parasternal and parascapular areas in healthy patients.

 

 

Adventitious breath sounds

• Adventitious breath sounds are extra lung sounds that may be heard in some patients superimposed upon the basic lung sounds. The main adventitious sounds can be divided into discontinuous and continuous sounds.
• • Discontinuous sounds include crackles/rales.
  • Continuous sounds include wheezes, rhonchi, stridor, and the rarely heard late inspiratory squeak or squawk.
  • A pleural rub defies easy classification as it may sound continuous or discontinuous.

 

 

Crackles (Rales)

• Crackles are discontinuous popping sounds that are heard primarily during inspiration. Contrary to popular opinion, they are not from the popping open of alveoli. In the larger airways they are thought to be caused by secretions bubbling in the airways, while in smaller airways they are thought to be caused by the popping open of the airways during inspiration. The sounds are varied, and are said to resemble the sound you hear when rubbing hair close to your ears, the crunching of leaves, or like the tearing of Velcro. Crackles may be differentiated by their quality (fine versus coarse) or by where they fall in inspiration.
• • 1. Early inspiratory crackles are heard in obstructive pulmonary disease (emphysema, asthma).
    2. Mid inspiratory crackles are heard in diseases of mid-sized airways such as bronchiectasis in cystic fibrosis.
    3. Late inspiratory crackles are the most common crackles, heard in diseases involving smaller airways, such as congestive heart failure, pneumonia, or pulmonary fibrosis. The crackles of pulmonary fibrosis often sound like the tearing of Velcro.

 

 

 Wheezes and rhonchi

 

These are continuous, musical sounds that are primarily heard in expiration – wheezes are high pitched and rhonchi are low pitched. They are both thought to be caused by vibrations in narrowed airways and are heard in asthma, reactive airways disease, and occasionally in heart failure (called cardiac asthma).

 

 

 Stridor

• This is a continuous, inspiratory wheeze that is heard loudest over the neck. It is a sign of upper airway obstruction, which could mean impending respiratory arrest, so requires immediate attention.

 

 

 Inspiratory squawk or squeak

This is a rare sound in late inspiration, that is short and musical. Heard in some types of interstitial lung disease.

 

 

Pleural friction rub

Heard when there is pleural inflammation, as in pneumonia or pulmonary infarction. It sounds like someone rubbing their hand on a wet balloon, or sometimes it sounds like a boot crunching on fresh snow.

 

 

Vocal resonance

• Vocal resonance is the practice of listening over the chest with the stethoscope while the patient speaks. Normally, the air-filled lung filters out speech so that it is muffled and unintelligible when listening to the chest. Vocal resonance is increased over areas of pneumonia.

1. 1. • Bronchophony is the finding of increased volume (loudness) of speech in a focal area of pneumonia.
      • Pectoriloquy is the finding that words are more clearly heard over an area of pneumonia.
      • Egophony is the finding that when the patient says E it sounds like A or “ah”, like the bleating of a goat. The mechanism is thought to be that the consolidated lung better transmits low frequency sounds and filters out some of the high frequency sounds, leading to this change in the sound.
      • Egophony may also be heard over a thin band of compressed lung over a pleural effusion.

 

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Clubbing

 

Clubbing of the digits is a cardinal sign of pulmonary disease. It is the finding of increased vascular connective tissue in the distal segments of the digits, which results in the characteristic enlargement of the tips of the digits and exaggerated curvature. Clubbing may occur in isolation, or it may be part of a syndrome called hypertrophic osteoarthropathy, in which periostosis (deposition of new bone) of long bones and joint pains also occur. Clubbing has been described as far back as the 5^th century BC by Hippocrates and is seen in a variety of disorders, including a number a pulmonary diseases caused by infections, inflammation, or malignancies. There have been a number of diagnostic criteria proposed for clubbing, but the three that are most widely accepted are:

• Increased interphalangeal depth ratio, meaning the end segment of the finger is thicker when viewed in profile than the middle segment.
• Increased hyponychial (Lovibond) angle, the angle from the finger to the nail (normally is about 160 degrees when seen in profile).
• Positive Schamroth sign – this is the obliteration of space between fingers when the nails are placed are placed face to face – the normal finding is a diamond of light coming through because  the preserved angle is less than 180 degrees.
• When palpating the clubbed digit, the increased connective tissue is spongy, and the nail can be easily rocked back and forth by putting alternating pressure on the proximal and distal edges of the nail as if the nail were a see-saw.
• Clubbing is thought to be caused by shunting of blood across the pulmonary vasculature resulting in the release of platelet derived growth factors in the distal extremities. These growth factors, such as PDGF and VEGF, are found in megakaryocytes which are normally trapped in the pulmonary circulation, but if the patient has a shunt, as in cyanotic heart disease, or pulmonary AV shunting, the megakaryocytes travel to the digits and release their growth factors there, causing the excess growth of tissue.
• Clubbing can develop and regress fairly rapidly, over a period of just a couple of weeks, when caused by infections such as lung abscesses or endocarditis. Clubbing can be seen in non-pulmonary diseases including cyanotic heart disease, liver disease, inflammatory bowel disease and vascular infections.

 

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Abnormal Breathing Patterns:

 

Kussmaul’s respirations

Kussmaul’s respirations are regular, rapid and deep respirations seen in patients with metabolic acidosis (both hyperpnea and tachypnea).

 

Cheyne-Stokes respirations

• Cheyne- Stokes respirations are characterized by periods of increasing hyperpnea that peak, then slow to an apneic period, followed by resumption of breathing and hyperpnea.
• Seen in patients with severe heart failure and stroke.

 

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Specific Lung Conditions

 

• Classic findings of pneumonia (with an open bronchus)

• • Inspection, may have reduced thoracic expansion on involved side
  • Palpation, increased tactile fremitus and reduced expansion by palpation
  • Percussion, dullness
  • Auscultation, bronchial breath sounds, crackles, and all of the vocal resonance signs are increased
  • (If the bronchus is closed, the findings are similar to a pleural effusion listed below)

 

 

• Classic findings in pleural effusion

  • Inspection, may have reduced thoracic expansion on involved side
  • Palpation, decreased tactile fremitus and expansion
  • Percussion, dullness
  • Auscultation, distant breath sounds (but may be bronchial over compressed lung at top of effusion and may have increased vocal fremitus at top as well)

 

 

• Classic findings in CHF

  • Inspection, no asymmetry of thoracic expansion
  • Palpation, no change (or symmetric decrease) in fremitus
  • Percussion, no changes (normal resonant)
  • Auscultation, breath sounds are bronchial or vesicular with crackles (usually late), no vocal resonance.

 

 

• Classic Findings in Pulmonary Fibrosis

  • Inspection, no asymmetry of thoracic expansion
  • Palpation, no change (or symmetric decrease) in fremitus
  • Percussion, no changes
  • Auscultation, breath sounds are vesicular with crackles.

 

 

• Classic Findings in COPD

  • Inspection, may have the appearance of increased AP diameter; may see use of accessory muscles, purse lip breathing, tripod stance
  • Palpation, decreased fremitus
  • Percussion, resonant to hyperresonant
  • Auscultation, decreased breath sounds, may have some early crackles, wheezes.