Physiology - Respiratory Mechanics Flashcards
What are the muscles of respiration? and examples of them.
Major inspiratory muscles e.g. diaphragm and external intercostal muscles.
Accessory muscles of inspiration (forceful) e.g. Sternocleidomastoid, scalenus and pectoral.
Muscles of active expiration e.g. Abs and internal intercostal muscles. Slide 4
What is the tidal volume and the residual volume?
Tidal = volume recorded during a single breath. Residual = volume that remains in lungs when fully exhaled. Slide 5
What makes up the total lung capacity?
Vital capacity volume and the residual volume. Slide 6
What are the 4 lung volumes and 4 lung capacities that can be recorded?
LV = Tidal, Inspiratory reserve, expiratory reserve and residual. LC = Inspiratory, functional residual, vital and total lung capacity. Slide 7+8
Does residual volume increase or decrease when the elastic recoil in the lungs is lost?
Increase. Slide 9
What is emphysema?
When the lungs lose the elastic recoil. Slide 9
What is FVC and FEV1 and what does it allow to be calculated?
Forced vital capacity and forced expiratory volume in one second. Allows the FEV1/FVC ratio to be calculated. Slide 10
What is the normal FEV1/FVC ratio?
> 70% if it is less they most likely have a obstructive lung disease. Slide 11
What is dynamic airway compression and who does it effect?
It effects people with airway obstructions e.g. asthma or COPD, and means that there is a collapsed airway due to rising pleural pressure in active expiration. Slide 18
What is a peak flow meter and what does it assess?
Gives an estimate of peak flow rate and assesses airway function. Short sharp blow in to the meter and is taken in a best of 3 attempts. Slide 19
What is pulmonary compliance?
It is the effort that has to go into stretching the lungs. Slide 20
The less compliant the lungs are, the …work is required to produce a given degree of inflation.
More work. Slide 20
What are the factors that can cause DECREASED pulmonary compliance?
Pulmonary fibrosis, oedema, lung collapse, pneumonia and absence of surfactant. Slide 21
What does decreased pulmonary compliance mean and how do you know someone has it?
Needs a greater change in pressure to change the volume of lungs so lungs are stiffer. It can be identified by shortness of breath especially on exertion and cause a restrictive pattern of lung volumes on spirometry. Slide 21
What does increased pulmonary compliance do and what signs can be seen?
If the elastic recoil of lungs is lost so during expiration, patients have to work harder to get air out (hyperinflation of lungs). Compliance increases with age. Slide 23
