Examination of the Lungs Examination of the lungs is best performed
with the patient sitting down and the upper body undressed.
Inspection can already yield signs for pulmonary conditions, such as a barrel chest caused
by emphysema. Additional diagnostic clues include an altered respiratory rate, an imbalance
between inspiration and expiration, or signs of dyspnea, such as intercostal retractions
or a notable use of the accessory muscles of respiration.
Now begins the percussion of the lungs. The examiner places one middle finger firmly
on the patient’s chest and strikes it with the middle finger of the other hand. Physiologically,
the air-filled pulmonary tissue should produce a resonant sound. Below the level of the lungs,
auscultation produces a dull sound. Percussion of the lungs is always performed
on both sides and should follow a predetermined pattern. The examination usually starts cranially,
about a hand’s width lateral to the spine and then moves caudally, alternating between
both sides.In the lower thoracic area, percussion is also conducted from medial to lateral.
Dullness to percussion can indicate effusion or, for example, a tumor. In contrast, hyperresonance
results from emphysema or pneumothorax. The mobility of the lungs is best assessed
by first determining the transition from resonance to dullness on complete exhalation, which
corresponds to the inferior border of the deflated lungs. Percussion is then repeated
on maximum inspiration to find the border while the lungs are inflated. The distance
between both borders determines pulmonary respiratory mobility.
Unilateral dullness to percussion should always be compared to the other side to confirm the
finding. Pleural effusion typically presents as dullness that rises from medial to lateral.
Respiratory expansion of the thorax can be checked by palpation. During expiration, the
examiner places both hands on the lateral thorax and applies mild pressure to create
skin folds. On inspiration, these folds should vanish bilaterally. In case of impaired ventilation,
for example in atelectasis or pneumothorax, respiratory expansion can be asymmetric.
Palpation is also used to assess tactile fremitus. If the patient is asked to say the words “Ninety-Nine”
in a deep voice, mild vibrations should be felt in the lower lung segments, around the
level of the 8th to 10th rib. Increased tactile fremitus, which indicates increased sound
conduction, can be found in, for example, pneumonia, whereas decreased fremitus - and
therefore decreased conduction - can result from pleural effusion.
Closely related to tactile fremitus, is bronchophony. The patient is asked to whisper “sixty-six”
while the examiner auscultates the lungs. In states of increased sound conduction, the
whisper is louder. If sound conduction is decreased, it is quieter, or may disappear
completely. The most important test when examining the
lungs is auscultation while the patient is breathing regularly and through the mouth.
It follows the same pattern as percussion. Auscultation allows evaluation of the breath
sounds, which can be diminished or increased, for instance. Furthermore, the ratio of inspiration
to expiration time should be noted. Auscultation may also reveal other abnormal findings, such
as dry or wet crackles, or pleural friction rub.
Breath sounds heard over normal pulmonary tissue are vesicular. Auscultation across
the upper airways results in bronchial breath sounds, which have a higher pitch in comparison.
Bronchial breath sounds heard over pulmonary tissue are considered pathological and hint
at the presence of pneumonia. Evaluating the right middle lobe is best achieved
through anterior auscultation. Therefore, if pneumonia is suspected, the lungs should
always be examined from the anterior as well. Auscultation is not limited to the lungs,
but should also include the trachea. Tracheal stenosis produces inspiratory stridor, which
can best be heard posteriorly in the paravertebral area, or anteriorly above the sternum.