Physiology 2 Flashcards
3 types of respiratory muscles
Major inspiration muscles
Accessory muscles of inspiration
Muscles of active expiration
What are the ‘major inspiration muscles’?
Diaphragm and external intercostal muscles
What are the ‘accessory inspiration muscles’?
Sternocleidomastoid, scalenus and pectoral muscles
Only contract during forceful inspiration
What are the ‘muscles of active expiration’?
Abdominal muscles and internal intercostal muscles
Contract during active expiration
Residual volume in the lungs is not measurable (true/false)
True - residual volume (leftover after exhale) can not be measured by spirometry, only estimated
Tidal volume (TV)
Volume of air in single breath (0.5L)
Inspiratory reserve volume (IRV)/expiratory reserve volume (ERV)
Extra volume which can be inhaled/exhaled (3.0/1.0L)
List of Lung volumes
Tidal volume
Inspiratory reserve volume
Expiratory reserve volume
Residual volume
List of lung capacities
Inspiratory capacity
Functional residual capacity
Vital capacity
Total lung capacity
Inspiratory capacity (IC)
Max volume inspired after normal expiration (3.7L)
Functional residual capacity (FRC)
Volume in lungs after passive expiration (2.2L)
Vital capacity
Max volume exhaled after maximal inspiration (4.5L)
Total lung capacity
Total volume lungs can hold (5.7L)
Spirometry
Test used to assess how well your lungs work (how much you inhale/exhale/how quickly)
What is spirometry used to diagnose?
Asthma, chronic obstructive pulmonary disease (COPD) and other breathing conditions
Air moves from ________ to ________ pressure with a small pressure gradient
High to low
What primarily determines airway resistance?
Radius radius of conducting airway
In bronchioles
Parasympathetic stimulation causes _____________
Sympathetic stimulation causes _____________
Bronchoconstriction
Bronchodilatation
Dynamic airway compression
makes active compression more difficult in patients with airway obstruction
Pressure (to push air out) is undesirable => airway becomes compressed
Dynamic airway compression causes problems in normal people (true/false)
False
Dynamic airway compression is only problems for those with airway obstruction
Peak flow meter
Gives estimate of peak flow rate
>useful in patients with obstructive lung disease
Pulmonary compliance
Lungs stretched during inspiration
Compliance - measure of effort put into stretching of distending lungs
decreased pulmonary compliance in lungs causes…
stiffer/harder to inflate lungs > more work required to produce given degree of inflation
Factors decreasing pulmonary compliance
Pulmonary fibrosis Pulmonary oedema Collapsed lung Pneumonia Absence of surfactant