Thorax and Lungs

midsternal line and the midclavicular line

Identify anatomical lines used to facilitate assessment of the *anterior chest* of the thoracic cavity.

anterior axillary, posterior axillary line, and midaxillary line

Identify anatomical lines used to facilitate assessment of the *lateral chest*

vertebral (or midspinal) line and the scapular line

Identify anatomical lines used to facilitate assessment of the *posterior chest* of the thoracic cavity.

lateral - lung

lung tissue extends from the apex of the axilla down to the 7th or 8th rib. the R upper lobe extends from the apex of the axilla down to the horizontal fissure at the 5th rib. the right middle lobe extends from the horizontal fissure down and forward to the 6th rib at the midclavicular line. the right lower lobe continues from the 5th rib to the 8th in the midaxillary line. the left lung contains only 2 lobes, upper and lower. these are seen laterally as two triangular areas separated by the oblique fissure. the L upper lobe continues down to the 8th rib in the midaxillary line

anterior - lungs

oblique (major or diagonal) fissure crosses the 5th rib in the midaxillary line and terminates at the 6th rib in the midclavicular line. the R lung also contains the horizontal (minor) fissure dividing the right upper and middle lobes. this fissure extends from the 5th rib in the R midaxillary line to the 3rd intercostal space or 4th rib at the R sternal border.

anterior chest palpation

palpate symmetric chest expansion by placing your hands on the anterolateral wall with the thumbs along the costal margins and pointing toward the xiphoid process. ask person to take a deep breath and watch your thumbs move apart symmetrically. assess tactile (vocal) fremitus by palpating over the lung apices in the supraclavicular areas, comparing vibrations fro one side to another as the person says "99". avoid palpating over female breast tissue. palpate anterior chest wall to note tenderness, lumps or masses, and skin mobility and turgor, and temperature and moisture.

lung borders

in the anterior chest the apex, or highest point of lung tissue is 3-4 cm above the inner 3rd of the clavicles. the base, lower border, rests on the diaphragm at about the 6th rib in the midclavicular line. laterally lung tissue extends from the apex of the axilla down to the 5th or 8th rib. posteriorly the location of C7 marks the apex of lung tissue and T10 usually corresponds to the base. deep inspiration expands the lungs, and their lower border drops to the level of T12.

left lung

is the narrower lung due to heart bulging to the left. contains 2 lobes

right lung

is the shorter lung, due to underlying liver. contains 3 lobes.

posterior - lungs

lower love mostly. upper lobes occupy tissue from T1 to T3 or T4. from here, the lower lobes begin and the inferior border reaches down to T10 on expiration, and T12 on inspiration. there's no right middle lobe on the posterior side. if the person puts their hands on their head, the division between the upper and lower lobes corresponds to the medial border of the scapulae.

breath sounds

posterior chest auscultation. instruct person to breathe deeply and evaluate the presence and quality of normal breath sounds. sitting, leaning forward slightly, with arms resting across lap. listen to at least one full respiration in each location, in a side-to-side comparison. while standing behind the person, listen to the following lung areas: posterior from the apices at C7 to the bases around T10 and laterally from the axilla down to the 7th and 8th rib. expect to hear three types of normal breath sounds: bronchial, bronchovesicular, and vesicular.

voice sounds

posterior chest auscultation. normal voice transmission is soft, muffled and indistinct; you cannot understand the words. pathology enhances transmission of voice sounds. not elicited routinely, usually only performed if you suspect lung pathology. tests for possible presence of bronchophony, egophony, and whispered pectoriloquy

adventitious sounds

posterior chest auscultation. note any of these sounds, as they're normally not heard in the lungs (ex. crackles, wheezes)

inspecting anterior chest

shape and configuration; ribs sloping downward with symmetric interspace; costal angle within 90 degrees; development of abdominal muscles; person's facial expression while breathing; level of consciousness; skin color and condition; quality of respirations, with chest expanding symmetrically, no retract or bulging of interspaces on inspiration; if there's use of accessory neck muscles (scalene, sternomastoid, trapezius); respiratory rate and pattern of breathing

anterior chest percussion

the apices in the supraclavicular areas, then the interspaces and comparing one side with the other, move down the anterior chest. shift breast tissue over slightly using the edge of your stationary hand. note borders of cardiac dullness, not confusing it with lung pathology, in the right hemithorax, the upper border of liver dullness is located in the 5th intercostal space in the right midclavicular line. on the left, tympany is evident over the gastric space.

pleural cavitirs

the left and right cavities on either side of the mediastinum, contain the lungs

mediastinum

the middle section of the thoracic cavity containing the esophagus, trachea, heart, and great vessels

posterior chest inspection

the thoracic cage; shape and configuration of the chest wall; symmetry of spinous processes, thorax and scapulae; downward sloping of ribs; ratio of anteroposterior (AP) to transverse is 0.70 to 0.75 in adults, increases with age; neck and trapezius muscles well developed; posture when person takes a breath; skin color and condition.

posterior chest palpation

consists of symmetric expansion and tactile fremitus

suprasternal notch

*Anterior Thoracic Landmark* Feel the follow U-shaped depression just above the sternum, between the clavicles

sternum

*Anterior Thoracic Landmark* The "breastbone" has 3 parts: the manubrium, the body, and the xiphoid process. Walk your fingers down the manubrium a few centimeters until you feel a distinct bony ridge, the sternal angle.

sternal angle/angle of louis (AOL)

*Anterior Thoracic Landmark* The articulation of the manubrium and the body of the sternum, and it is continuous with the second rib. The AOL is a useful place to start counting ribs, which helps localize a respiratory finding horizontally. Identify this angel, palpate to the 2nd rib, and slide down to the second intercostal space. Each intercostal space is numbered by the rib above it. Continue counting down the ribs in the middle of the hemithorax, not close to the sternum where the costal cartilages lie too close together to count. You can palpate easily down to the 10th rib. The AOL also marks the site of tracheal bifurcation into the R and L main bronchi; it corresponds with the upper border of the atria of the heart, and it lies about the 4th thoracic vertebra on the back.

costal angle

*Anterior Thoracic Landmark* the right and left costal margins form an angle where they meet at the xiphoid process. usually 90 degrees or less, this angle increases when the rib cage is chronologically overinflated, as in emphysema.

spinous processes

*Posterior Thoracic Landmark* Count down these knobs on the vertebrae, which stack together to form the spinal column. Note that the spinous processes align with their same numbered ribs only down to T4. After T4, the spinous processes angle downward from the vertebral body and overlie the vertebral body and rib below.

twelfth rib

*Posterior Thoracic Landmark* palpate midqay between the spine and the person's side to identify its free tip.

vertebra prominens

*Posterior Thoracic Landmark* start here. flex your hand and feel for C7.

inferior border of the scapula

*Posterior Thoracic Landmark* the scapulae are located symmetrically in each hemithorax. the lower tip is usually the seventh or eighth rib.

reference lines

use the reference lines to pinpoint a finding vertically on the chest. the midclavicular line bisects the center of each clavicle at a point halfway between the palpated sternoclvicular and acromioclavicular joints. the posterior chest walls have two lines (references in #1) that extend from the inferior angle of the scapular when the arms are at the sides of the body. life the person's arm 90 degrees and divide the lateral chest by 3 lines (references in #1). The anterior line extends down from the anterior axillary fold where the pectoralis major muscle inserts; the posterior line continues down from the posterior fold where the latissimus dorsi muscle inserts; the midaxillary line runs down from the apex of the axilla and lies between and parallel to the other two.

symmetric expansion

used during posterior chest palpation. Place your warm hands sideways on the posterolateral chest wall with thumbs pointing at the level of T9 or T10. Ask person to take a deep breath. Your thumbs should move apart symmetrically.

tactile fremitus

used during posterior chest palpation. use either the palmar base (the ball) of the fingers or the ulnar edge of one hand and touch the person's chest while he or she repeats "99". start over the lung apices and palpate from one side to another. vibrations should feel the same in the corresponding area on each side. avoid palpating over scapulae, the bone damps the sound transmission. fremitus is more prominent between scapulae and around sternum, and decreases as you progress down. it feels greater over a thin chest wall versus an obese or heavily muscular one. a loud, low-pitched voice generates more fremitus than a soft, high-pitched one. using the fingers, gently palpate the entire chest wall, checking for tenderness, skin temperature and moisture, lumps or masses, and lesions noted on inspection.

diaphragmatic excursion

used during posterior chest percussion. map out the lower lung border in expiration and inspiration, asking the person to exhale and hold it while you percuss down the scapular line until sound becomes dull. this estimates the level of the diaphragm separating the lungs from the abdominal viscera. it may be higher on the right side because of the liver. perform same thing while person takes a deep breath and holds it. measure the vertical difference. normal is 3-5 cm in adults, or 7-8 in well conditioned people.

lung fields

used during posterior chest percussion. start at the apices, percuss across shoulders. then, percuss in the interspaces, making a side to side comparison all the way down to the lung region, in 5 cm intervals. note resonance (low pitched, clear hollow sound), which may be duller in the athlete or obese person. percussion sets into motion the outer 5-7 cm of tissue. abnormal finding must be 2-3 cm wide to yield abnormal percussion