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Page 1
The 4 major components of the lung exam (inspection, palpation,
percussion and auscultation) are also used to examine the heart
and abdomen. Learning the appropriate techniques at this
juncture will therefore enhance your ability to perform these
other examinations as well. Vital signs, an important source of
information, are discussed elsewhere.
Inspection/Observation: A great deal of information
can be gathered from simply watching a patient breathe. Pay
particular attention to:
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General comfort and breathing pattern of the patient. Do
they appear distressed, diaphoretic, labored? Are the
breaths regular and deep?
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Use of accessory muscles of breathing (e.g. scalenes,
sternocleidomastoids). Their use signifies some element of
respiratory difficulty.
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Color of the patient, in particular around the lips and
nail beds. Obviously, blue is bad!
Cyanosis of nail beds
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The position of the patient. Those with extreme
pulmonary dysfunction will often sit up-right. In cases of
real distress, they will lean forward, resting their hands
on their knees in what is known as the tri-pod position.
Patient with emphysema bending over in Tri-Pod
Position
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Breathing through pursed lips, often seen in cases of
emphysema.
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Ability to speak. At times, respiratory rates can be so
high and/or work of breathing so great that patients are
unable to speak in complete sentences. If this occurs, note
how many words they can speak (i.e. the fewer words per
breath, the worse the problem!).
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Any audible noises associated with breathing as
occasionally, wheezing or the gurgling caused by secretions
in large airways are audible to the "naked" ear.
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The direction of abdominal wall movement during
inspiration. Normally, the descent of the diaphragm pushes
intra-abdominal contents down and the wall outward. In cases
of severe diaphragmatic flattening (e.g. emphysema) or
paralysis, the abdominal wall may move inward during
inspiration, referred to as paradoxical breathing. If you
suspect this to be the case, place your hand on the
patient's abdomen as they breathe, which should accentuate
its movement.
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Any obvious chest or spine deformities. These may arise
as a result of chronic lung disease (e.g. emphysema), occur
congenitally, or be otherwise acquired. In any case, they
can impair a patient's ability to breathe normally. A few
common variants include:
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Pectus excavatum: Congenital posterior displacement
of lower aspect of sternum. This gives the chest a
somewhat "hollowed-out" appearance. The x-ray shows a
subtle concave appearance of the lower sternum.
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Barrel chest: Associated with emphysema and lung
hyperinflation. Accompanying x-ray also demonstrates
increased anterior-posterior diameter as well as
diaphragmatic flattening.
Palpation: Palpation plays a relatively minor role in
the examination of the normal chest as the structure of interest
(the lung) is covered by the ribs and therefore not palpable.
Specific situations where it may be helpful include:
Accentuating normal chest excursion: Place your hands on
the patient's back with thumbs pointed towards the spine.
Remember to first rub your hands together so that they are
not too cold prior to touching the patient. Your hands
should lift symmetrically outward when the patient takes a
deep breath. Processes that lead to asymmetric lung
expansion, as might occur when anything fills the pleural
space (e.g. air or fluid), may then be detected as the hand
on the affected side will move outward to a lesser degree.
There has to be a lot of pleural disease before this
asymmetry can be identified on exam.
Detecting Chest Excursion
Tactile Fremitus: Normal lung transmits a palpable
vibratory sensation to the chest wall. This is referred to
as fremitus and can be detected by placing the ulnar aspects
of both hands firmly against either side of the chest while
the patient says the words "Ninety-Nine." This maneuver is
repeated until the entire posterior thorax is covered. The
bony aspects of the hands are used as they are particularly
sensitive for detecting these vibrations.
Assessing Fremitus
Pathologic conditions will alter fremitus. In particular:
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Lung consolidation: Consolidation occurs when the
normally air filled lung parenchyma becomes engorged
with fluid or tissue, most commonly in the setting of
pneumonia. If a large enough segment of parenchyma is
involved, it can alter the transmission of air and
sound. In the presence of consolidation, fremitus
becomes more pronounced.
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Pleural fluid: Fluid, known as a pleural effusion,
can collect in the potential space that exists between
the lung and the chest wall, displacing the lung
upwards. Fremitus over an effusion will be decreased.
In general, fremitus is a pretty subtle finding and
should not be thought of as the primary means of identifying
either consolidation or pleural fluid. It can, however, lend
supporting evidence if other findings (see below) suggest
the presence of either of these processes.
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Effusions and infiltrates can
perhaps be more easily understood using a sponge
to represent the lung. In this model, an
infiltrate is depicted by the blue coloration
that has invaded the sponge itself (sponge on
left). An effusion is depicted by the blue fluid
upon which the lung is floating (sponge on
right). |
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Investigating painful areas: If the patient complains of
pain at a particular site it is obviously important to
carefully palpate around that area. In addition, special
situations (e.g. trauma) mandate careful palpation to look
for evidence of rib fracture, subcutaneous air (feels like
your pushing on Rice Krispies or bubble paper), etc.
Percussion: This technique makes use of the fact that
striking a surface which covers an air-filled structure (e.g.
normal lung) will produce a resonant note while repeating the
same maneuver over a fluid or tissue filled cavity generates a
relatively dull sound. If the normal, air-filled tissue has been
displaced by fluid (e.g. pleural effusion) or infiltrated with
white cells and bacteria (e.g. pneumonia), percussion will
generate a deadened tone. Alternatively, processes that lead to
chronic (e.g. emphysema) or acute (e.g. pneumothorax) air
trapping in the lung or pleural space, respectively, will
produce hyper-resonant (i.e. more drum-like) notes on
percussion. Initially, you will find that this skill is a bit
awkward to perform. Allow your hand to swing freely at the
wrist, hammering your finger onto the target at the bottom of
the down stroke. A stiff wrist forces you to push your finger
into the target which will not elicit the correct sound. In
addition, it takes a while to develop an ear for what is
resonant and what is not. A few things to remember:
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If you're percussing with your right hand, stand a bit
to the left side of the patient's back.
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Ask the patient to cross their hands in front of their
chest, grasping the opposite shoulder with each hand. This
will help to pull the scapulae laterally, away from the
percussion field.
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Work down the "alley" that exists between the scapula
and vertebral column, which should help you avoid percussing
over bone.
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Try to focus on striking the distal inter-phalangeal
joint (i.e. the last joint) of your left middle finger with
the tip of the right middle finger. The impact should be
crisp so you may want to cut your nails to keep
blood-letting to a minimum!
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The last 2 phalanges of your left middle finger should
rest firmly on the patient's back. Try to keep the remainder
of your fingers from touching the patient, or rest only the
tips on them if this is otherwise too awkward, in order to
minimize any dampening of the percussion notes.
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When percussing any one spot, 2 or 3 sharp taps should
suffice, though feel free to do more if you'd like. Then
move your hand down several inter-spaces and repeat the
maneuver. In general, percussion in 5 or so different
locations should cover one hemi-thorax. After you have
percussed the left chest, move yours hands across and repeat
the same procedure on the right side. If you detect any
abnormality on one side, it's a good idea to slide your
hands across to the other for comparison. In this way, one
thorax serves as a control for the other. In general,
percussion is limited to the posterior lung fields. However,
if auscultation (see below) reveals an abnormality in the
anterior or lateral fields, percussion over these areas can
help identify its cause.
Percussion Technique
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The goal is to recognize that at some point as you move
down towards the base of the lungs, the quality of the sound
changes. This normally occurs when you leave the thorax. It
is not particularly important to identify the exact location
of the diaphragm, though if you are able to note a
difference in level between maximum inspiration and
expiration, all the better. Ultimately, you will develop a
sense of where the normal lung should end by simply looking
at the chest. The exact vertebral level at which this occurs
is not really relevant.
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"Speed percussion" may help to accentuate the difference
between dull and resonant areas. During this technique, the
examiner moves their left (i.e. the non-percussing) hand at
a constant rate down the patient's back, tapping on it
continuously as it progresses towards the bottom of the
thorax. This tends to make the point of inflection (i.e.
change from resonant to dull) more pronounced.
Practice percussion! Try finding your own stomach bubble, which
should be around the left costal margin. Note that due to the
location of the heart, tapping over your left chest will produce
a different sound then when performed over your right. Percuss
your walls (if they're sheet rock) and try to locate the studs.
Tap on tupperware filled with various amounts of water. This not
only helps you develop a sense of the different tones that may
be produced but also allows you to practice the technique.
Page 2
Review of Lung Anatomy: Understanding the pulmonary
exam is greatly enhanced by recognizing the relationships
between surface structures, the skeleton, and the main lobes of
the lung. Realize that this can be difficult as some surface
landmarks (e.g.. nipples of the breast) do not always maintain
their precise relationship to underlying structures.
Nevertheless, surface markers will give you a rough guide to
what lies beneath the skin. The pictures below demonstrate these
relationships. The multi-colored areas of the lung model
identify precise anatomic segments of the various lobes, which
cannot be appreciated on examination. Main lobes are outlined in
black. The following abbreviations are used: RUL = Right Upper
Lobe; LUL = Left Upper Lobe; RML = Right Middle Lobe; RLL =
Right Lower Lobe; LLL = Left Lower Lobe.
Also
See: Pulmonary Anatomy
Anatomic Relationship of Heart and
Lungs
Right Lung Anatomy
Page 3
Auscultation: Prior to listening over any one area of
the chest, remind yourself which lobe of the lung is heard best
in that region: lower lobes occupy the bottom 3/4 of the
posterior fields; right middle lobe heard in right axilla;
lingula in left axilla; upper lobes in the anterior chest and at
the top 1/4 of the posterior fields. This can be quite helpful
in trying to pin down the location of pathologic processes that
may be restricted by anatomic boundaries (e.g. pneumonia). Many
disease processes (e.g. pulmonary edema, bronchoconstriction)
are diffuse, producing abnormal findings in multiple fields.
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Put on your stethoscope so that the ear pieces are
directed away from you. Adjust the head of the scope so that
the diaphragm is engaged. If you're not sure, scratch
lightly on the diaphragm, which should produce a noise. If
not, twist the head and try again. Gently rub the head of
the stethoscope on your shirt so that it is not too cold
prior to placing it on the patient's skin.
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The upper aspect of the posterior fields (i.e. towards
the top of the patient's back) are examined first. Listen
over one spot and then move the stethoscope to the same
position on the opposite side and repeat. This again makes
use of one lung as a source of comparison for the other. The
entire posterior chest can be covered by listening in
roughly 4 places on each side. Of course, if you hear
something abnormal, you'll need to listen in more places.
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The lingula and right middle lobes can be examined while
you are still standing behind the patient.
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Then, move around to the front and listen to the
anterior fields in the same fashion. This is generally done
while the patient is still sitting upright. Asking female
patients to lie down will allow their breasts to fall away
laterally, which may make this part of the examination
easier.
A few additional things worth noting.
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Don't get in the habit of performing auscultation
through clothing.
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Ask the patient to take slow, deep breaths through their
mouths while you are performing your exam. This forces the
patient to move greater volumes of air with each breath,
increasing the duration, intensity, and thus detectability
of any abnormal breath sounds that might be present.
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Sometimes it's helpful to have the patient cough a few
times prior to beginning auscultation. This clears airway
secretions and opens small atelectatic (i.e. collapsed)
areas at the lung bases.
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If the patient cannot sit up (e.g. in cases of
neurologic disease, post-operative states, etc.),
auscultation can be performed while the patient is lying on
their side. Get help if the patient is unable to move on
their own. In cases where even this cannot be accomplished,
a minimal examination can be performed by listening
laterally/posteriorly as the patient remains supine.
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Requesting that the patient exhale forcibly will
occasionally help to accentuate abnormal breath sounds (in
particular, wheezing) that might not be heard when they are
breathing at normal flow rates.
Go
to Our Lung Sounds Page
What can you expect to hear? A few basic sounds to listen
for:
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A healthy individual breathing through their mouth at
normal tidal volumes produces a soft inspiratory sound as
air rushes into the lungs, with little noise produced on
expiration. These are referred to as vesicular breath
sounds.
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Wheezes are whistling-type noises produced during
expiration (and sometimes inspiration) when air is forced
through airways narrowed by bronchoconstriction, secretions,
and/or associated mucosal edema. As this most commonly
occurs in association with diffuse processes that affect all
lobes of the lung (e.g. asthma and emphysema) it is
frequently audible in all fields. In cases of significant
bronchoconstriction, the expiratory phase of respiration
(relative to inspiration) becomes noticeably prolonged.
Clinicians refer to this as an increased I to E ratio.
Normal is approximately 1:2 (i.e. expiration twice as long
as inspiration) though actual timed measurements are neither
practical nor reliable. Focus instead on simple observation,
noting whether E seems >> I. The greater the difference, the
worse the obstruction. Occasionally, focal wheezing can
occur when airway narrowing if restricted to a single
anatomic area, as might occur with an obstructing tumor or
bronchoconstriction induced by pneumonia. Wheezing heard
only on inspiration is referred to as stridor and is
associated with mechanical obstruction at the level of the
trachea/upper airway. This may be best appreciated by
placing your stethoscope directly on top of the trachea.
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Rales (a.k.a. crackles) are scratchy sounds that occur
in association with processes that cause fluid to accumulate
within the alveolar and interstitial spaces. The sound is
similar to that produced by rubbing strands of hair together
close to your ear. Pulmonary edema is probably the most
common cause, at least in the older adult population, and
results in symmetric findings. This tends to occur first in
the most dependent portions of the lower lobes and extend
from the bases towards the apices as disease progresses.
Pneumonia, on the other hand, can result in discrete areas
of alveolar filling, and therefore produce crackles
restricted to a specific region of the lung. Very distinct,
diffuse, dry-sounding crackles, similar to the noise
produced when separating pieces of velcro, are caused by
pulmonary fibrosis, a relatively uncommon condition.
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Dense consolidation of the lung parenchyma, as can occur
with pneumonia, results in the transmission of large airway
noises (i.e. those normally heard on auscultation over the
trachea… known as tubular or bronchial breath sounds) to the
periphery. In this setting, the consolidated lung acts as a
terrific conducting medium, transferring central sounds
directly to the edges. It's very similar to the noise
produced when breathing through a snorkel. Furthermore, if
you direct the patient to say the letter 'eee' it is
detected during auscultation over the involved lobe as a
nasal-sounding 'aaa'. These 'eee' to 'aaa' changes are
referred to as egophony. The first time you detect it,
you'll think that the patient is actually saying 'aaa'… have
them repeat it several times to assure yourself that they
are really following your directions!
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Secretions that form/collect in larger airways, as might
occur with bronchitis or other mucous creating process, can
produce a gurgling-type noise, similar to the sound produced
when you suck the last bits of a milk shake through a straw.
These noises are referred to as ronchi.
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Auscultation over a pleural effusion will produce a very
muffled sound. If, however, you listen carefully to the
region on top of the effusion, you may hear sounds
suggestive of consolidation, originating from lung which is
compressed by the fluid pushing up from below. Asymmetric
effusions are probably easier to detect as they will produce
different findings on examination of either side of the
chest.
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Auscultation of patients with severe, stable emphysema
will produce very little sound. These patients suffer from
significant lung destruction and air trapping, resulting in
their breathing at small tidal volumes that generate almost
no noise. Wheezing occurs when there is a superimposed acute
inflammatory process (see above).
Most of the above techniques are complimentary. Dullness
detected on percussion, for example, may represent either lung
consolidation or a pleural effusion. Auscultation over the same
region should help to distinguish between these possibilities,
as consolidation generates bronchial breath sounds while an
effusion is associated with a relative absence of sound.
Similarly, fremitus will be increased over consolidation and
decreased over an effusion. As such, it may be necessary to
repeat certain aspects of the exam, using one finding to confirm
the significance of another. Few findings are pathognomonic.
They have their greatest meaning when used together to paint the
most informative picture.
The Dynamic Lung Exam:
Pulse Oximeter
Oftentimes, a patient will complain of a symptom that is
induced by activity or movement. Shortness of breath on
exertion, one such example, can be a marker of significant
cardiac or pulmonary dysfunction. The initial examination may be
relatively unrevealing. In such cases, consider observed
ambulation (with the use of a pulse oximeter, a device that
continuously measures heart rate and oxygen saturation, if
available) as a dynamic extension of the cardiac and pulmonary
examinations. Quantifying a patient's exercise tolerance in
terms of distance and/or time walked can provide information
critical to the assessment of activity induced symptoms. It may
also help unmask illness that would be unapparent unless the
patient was asked to perform a task that challenged their
impaired reserves. Pay particular attention to the rate at which
the patient walks, duration of activity, distance covered,
development of dyspnea, changes in heart rate and oxygen
saturation, ability to talk during exercise and anything else
that the patient identifies as limiting their activity. The
objective data derived from this low tech test can aid you in
determining disease and symptom severity, helping to create a
list of possible diagnoses and assisting you in the rational use
of additional tests to further delineate the nature of the
problem. This can be particularly helpful in providing objective
information when symptoms seem out of proportion to findings. Or
when patients report few complaints yet seem to have a
considerable amount of disease. It will also generate a
measurement that you can refer back to during subsequent
evaluations in order to determine if there has been any real
change in functional status.
UCSD
School of Medicine; Content and Photographs by Charlie Goldberg,
M.D., UCSD School of Medicine and VA Medical Center, San Diego,
California 92093-0611.
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