Pulmonary Mechanics Flashcards
What is inspiratory reserve volume?
inspiration max minus max tidal volume
What is expiratory reserve volume?
minimum tidal volume minus maximum expiration
What is tidal volume?
The volume that happens in a each breath
What is inspiratory capacity?
difference between maximum inspiration and minimum tidal volume
What is functional residual capacity?
difference between minimum tidal volume and physical max emptiness
What is residual volume?
difference between maximum expiration and physical maximum emptiness
What is total lung capacity?
maximum physical differene between full lung and physically empty lung
What is transpulmonary pressure?
Palv-Ppl
What is the order of inspiration?
diaphragm and inspiratory intercostals contract thorax expands Ptp becomes more subatmospheric increase tranpulmonary pressure lungs expand Palv becomes subatmospheric air flows into alveoli
What determines airflow?
Flow=(Palv-Patm)/airway resistance
What are the simplle keys to spirometry interpretation?
look at FEV1/FBC ratio and the numbers
What does a low ratio indicate on spirometry
an obstructive procss
What si teh normal ratio for normal spirometry?
0.7 to 0.87 depending on demographic of patient
What is bronchodilator responsivity?
a significant response to bronchodilator when FBC or FEV1 increases at least 12%
What is the hallmark of a restrictive lung deficity?
reduced TLC
What are the role of type 1 pneumocytes?
alveolar, cover 95% of alveolar surface
What are the type II pneumocytes function?
produce surfacant
repair of alveolar epithelium
What are the types of obstructive lung disease?
ephysema
chronic bornchitis
asthma
bronchiectasis
What is forced vital capacity?
lungs are focibly emptied at maximal speed from full point of inspiration
What is FEV1?
forced expiratory volume in 1 second
What is FEV1:FVC ratio?
useful for detecting obstruction and differentiating form restrictvie lung disease
What is obstructive lung disease?
airway disorder-trachea to terminal bronchiole
increased resistance to air flow and limited expiratory rates on forced expiration
reduced FEV1:FVC
What is restrictive lung disease?
parenchymal disorder-respiratory bronchiole, alveoli and alveolar ducts
decreased expansion with reuced total lung capacity, O2 diffusing capacity, lung volumes and compliance
up FEV1:FVC ratio
What is emphysema?
permanent enlargment of all or part of hte respiratory unit accompanies by wall destruction without obvious fibrosis
What is the pathogensis behind emphysema?
increased number of macrophages, CD8 and neutrophils
neutrophils and macrophages are activated by tissue damage from cigarette smoke
elastase and free radicals derive from neutrophils and macrophages
up elastase down antielastase – portease-antiportease mechanism
up oxidants and down antioxidants
destruction of elastic tissue
increased comliance and decreased elasticity
What is centriacinar emphysema?
smokers emphsema, apical segment of upper lobe
What is panacinar emphysema?
alpha-antitrypsin deficiency
AD genetic
lower lobes
all parts of respiratory unit
What is alpha-antitrypsin devciency?
total lack of antiproteases throughout acinus
lower lung dustribution wherer perfusion and neutrophil numbers are graetest
smoking greatly accelerates this process
What are the clinical finidngs of emphysema?
severe and early onset of dyspnea pink puffers coexistaence with chronic bronchitis cor pulmonale diminished breath sounds due to hyperinflation
What is CXR emphysema finidings?
increased AP diameter
hyperlucent
vertical heart
depresed diaphragm
What is paraseptal emphysema?
subpleural involvement
spontaneous pneumothorax
no COPD
What is irregular emphysema?
localized scar associated
no COPD
What is chronic bornchitis?
productive cough for at least 3 months for two consecutive years
inhaled smoke is irritant leads to mucous hypersecretion airflow obstruction in terminal bronchioles, irreversible fibroiss of terminal bronchioles
infection maintenaince of disease and acute exacerbations
bronchospasm
What are the clinical findings of chrnoic bronchitis?
productive cough cyansosis blue bloaters dyspnea expiratory wheezing and ronchi cor pulmonale
What does a CXR show from chronic bronchitis?
enlarged heart, horizontally oriented
increased bronchial markings
