Thorax and Lungs (Exam 2) Flashcards
Thoracic Cage Structure
• sternum
• 12 pairs of ribs
• 12 thoracic vertebrae
• diaphragm
Diaphragm
floor of the thoracic cage; separates the thoracic cavity from the abdomen
Anterior Thoracic Landmarks (4)
• suprasternal notch (jugular notch)
• sternum
• eternal angle (angle of Louis)
• costal angle
Components of the sternum (3)
• manubrium
• body
• xiphoid process
Components of the sternal angle
• location to begin counting ribs
• site of tracheal bifurcation into right and left main bronchi
Costal angle
90° angle or less, increases with chronic inflammation
Why is it more difficult to count ribs posteriorly?
presence of muscle mass and soft tissue
Posterior Thoracic Landmarks (3)
• vertebra prominens
• spinous processes
• inferior border of the scapula
Vertebra prominens
• beginning point
• flex the head and feel for most prominent bony spur
Spinous processes
number correlates with rib number, angle downward from their vertebral body (T1, T2, etc.)
Anterior Chest Reference Lines (2)
midsternal line and midclavicular line
Lateral Chest Reference Lines (3)
anterior axillary, posterior axillary, and midaxillary
Posterior Chest Reference Lines (2)
vertebral (midspinal) line and scapular line
Mediastinum
middle section of thoracic cavity containing the esophagus, trachea, heart and great vessels
Pleural cavities
right and left, contains the lungs
Apex of the lung
3-4 cm above clavicle
Base of the lung
lower border, rests on the diaphragm
Right Lung v. Left Lung: Right
• shorter than the left
• has three lobes
• lobes are separated by fissures (oblique lines)
Right Lung v. Left Lung: Left
• longer than the right
• narrower than the right (heart bulges to the left)
• two lobes separated by oblique lines
What are pleurae and what are the 2 types?
serous membranes that form an envelope between the lungs and the chest wall; visceral and parietal
Visceral pleura
lines the outside of the lungs
Parietal pleura
lines the inside of the chest wall and diaphragm
Pleural cavity- Inside the envelope
space filled with few mL of lubricating fluid, which enables lung movement during breathing; vacuum or negative pressures to hold lungs tightly against the chest wall
Costodiaphragmatic recess
pleural space beneath the lungs; potential space for abnormal fill with fluid or air which compromises lung expansion
Bronchia components for protection (2)
• goblet cells
• cilia
Goblet cells
secrete mucous to entrap particles
Cilia
sweep particles upward to be expelled/swallowed
Acinus (functional respiratory unit) Components (4)
• bronchioles
• alveolar ducts
• alveolar sacs
• alveoli
GAS EXCHANGE OCCURS HERE
4 major functions of the respiratory system
I- supplying oxygen to the body for energy production
II- removing CO2 as a waste product of energy reactions
III- maintaining homeostasis (acid/base balance)
IV- maintaining heat exchange
Control of Respirations MAJOR FEEDBACK LOOP includes…(3)
• increase of CO2 in the blood (hypercapnia) is normal stimulus to breathe
• cellular demands may alter breathing patterns subconsciously
• respiratory control center in the brainstem results in involuntary breathing
Inspiration
air rushes into lungs
• diaphragm contracts, descends, and flattens
• FORCED inspiration due to exercise or chronic disease uses accessory neck muscle
Expiration
chest recoil, air is expelled and diaphragm relaxes
• FORCED expiration uses abdominal muscles to assist diaphragm
Vertical diameter of thoracic during respirations
downward/upward movement of diaphragm
Anteroposterior (AP) diameter of thoracic during respirations
elevation or depression of the ribs; increases or decreases
Developmental Considerations: Pregnant Women
• increased O2 demand from fetus
• enlarged uterus displaces diaphragm
• increased estrogen levels relax chest cage ligaments, allowing costal angle widening
Developmental Considerations: The Aging Adult
• costal cartilage becomes calcified and thorax is less mobile
• lung is more rigid and harder to inflate
• decreased number of alveoli, meaning less available surface area for gas exchange
• MORE AT RISK FOR POST OP COMPLICATIONS (decreased ability to cough, loss of protective reflexes, increased secretions)
Subjective Data: Respiratory System (13)
• cough (OLDCARTS)
• sputum (color, odor?)
• hemoptysis (coughing up blood)
• dyspnea (orthopnea, paroxysmal nocturnal dyspnea)
• chest pain (with/without breathing?)
• history of respiratory infections
• fatigue
• past health history
• family history
• psychosocial (child w/asthma? elderly w/memory concerns?)
• environmental conditions (working with pollutants?)
• smoking (pack years- # of packs/day x years)
• weight changes, fever, night sweats (TB?)