Week 8 (EXAM 2) Flashcards
Describe the structure of the lung
Cone shaped with an apex, base and 3 borders (anterior, inferior and posterior)
Apex highest point in the root of the neck, 1 inch above each clavicle
Base is concave resting on the convex surface of the diaphragm
Anterior border of left lung has cardiac notch
R lung is heavier and wider than the L lung;
shorter than the L lung due to the liver
L lung is longer and thinner than the R lung
due to the heart and pericardium
What are the lobes of R & L lungs
3 on the right upper, middle and lower
2 on the left upper and lower
What are the fissures of R & L lungs
Right has horizontal fissure which separates the RUL and RML, and oblique fissure that separates the RUL/RML and RLL
Left has oblique fissure which separates the LUL and LLL
What are the segments of R & L lungs
Segments:
Each lobe is further subdivided into segments
Both upper lobes have apical, anterior and posterior segments (harder to separate on the left)
RML has medial and lateral segments
Left lung has lingual segment instead (wraps around heart)
Both lower lobes have anterior basal, posterior basal, superior basal and lateral basal segments
What are the muscles of inspiration?
Diaphragm
Main muscle of inspiration External
Intercostal muscles
Slope forward and downward
Pull ribs up and outward
What are the ventilation mechanics
Resting:
1) 760 mm Hg inrapulmonic and intrapleural pressure (atmospheric pressure)
Inspiration:
1) muscles contract so the chest wall moves out
2) diaphragm descends
3) intrapulmonic pressure more negative to 758 mm Hg
4) intrapleural pressure more negative to 754 mm Hg
5) air (at atmospheric pressure 760) flows in
Expiration:
1) muscles relax so chest wall moves inward
2) diaphragm ascends
3) intrapleural pressure remains negative
4) intrapulmonary pressure becomes positive (763 mm Hg)
5) air flows out
What are the components of the lower respiratory tract?
conducting zone: (trachea and terminal bronchioles)
Considered anatomic dead space
air transport
humidification
warming
particle filtration
vocalization
immunoglobulin secretion
Respiratory zone: (bronchioles, alveolar ducts, alveoli)
gas exchange
surfactant production
molecule activation and inactivation
blood clotting regulation
endocrine function
What is Chronic Obstructive Pulmonary Disease (COPD)?
3rd most deadly disease
Common: global prevalence of about 174 million cases; contributes to major disability and economic/social
burdens
Risk factors: primarily tobacco smoke inhalation
Physical inactivity, increased age, early life events and inflammation
Group of chronic, obstructive lung diseases
(VIP) Affect the airways and lung parenchyma that produce obstruction to expiratory airflow
Trouble getting air OUT
Most individuals with COPD have a combination of chronic bronchitis, emphysema and airway hyperactivity
Also includes cystic fibrosis, bronchiectasis and bronchopulmonary dysplasia
What are the types of COPD?
(people can have multiple or just one)
1) Emphysema
Parenchymal alveolar disease. Destruction of alveolar walls, enlargement of airspaces distal to
the terminal bronchioles. Balance between destruction and repair of the respiratory bronchioles, alveolar ducts and alveoli.
2) Chronic bronchitis
Small airway disease. Presence of a chronic productive cough for 3 months in each of 2 successive years. Hypersecretion of mucus in the large airways smaller airways.
3) Asthma
Chronic inflammatory disorder of the airways. Recurrent episodes with variable airflow obstruction
that is often reversible. Hyperresponsiveness to stimuli.
What is COPD etiology?
2 primary causes (Inhalation factors and genetics)
1) Inhalation of cigarette smoke is the primary cause
Active or passive
Risk for developing COPD is 30x greater in smokers than nonsmokers
2) Genetics
Alpha1-antitrypsin deficiency (emphysema: damage to walls of alveoli)
Primarily affects the surfactant production and integrity of the alveolar sac
What is the pathophysiology of COPD?
Characterized by inflammation of the airway and decreased airflow to the lung caused by an irreversible
narrowing
Ultimately disappearance of small conducting airways and bronchioles
Cycle of tissue damage causing an inflammatory cascade and immune response tissue damage
Exacerbated by increased age and altered immune response
How does COPD present?
1) Obstruction can be related to any or all the following:
Retained secretions
Inflammation of the mucosal lining of airways
Bronchial constriction
Weakening of support structure of airway walls
Air sac destruction and over-inflation
2) Episodic wheezing with a variable degree of chronic bronchitis and emphysema
3) Chest x-ray
Hyperinflated lungs, flattened diaphragm and enlarged R ventricle
4) Incomplete emptying of the lung
Reduced lung function as noted on PFT
What are common traits of COPD?
Decreased activity tolerance
Increased anxiety
Wheezing
Tripoding “hand on knee”
Pursed lip breathing
Clubbing “low O2 to finger tips”
Cyanosis
Secretion production
Cough
Dyspnea or SOB
Explain what’s wrong
R image:
Hyperinflated lungs (appear darker on x-rays due to increased amount of air vs normal tissue)
How is COPD diagnosed?
1) Spirometry
Gold standard for diagnosis and monitoring
Measure of airflow limitation
2) Arterial Blood Gases
3) Chest x-ray
4) Percussion “tapping body parts with fingers”
5) Auscultation “listening to sounds of body during physical examination”
How is lung volume affected when it is obstructed?
Reduced: IC, ERV, VC
Increased: RV, FRC, TLC
