Respiration III Flashcards
What are the two types of lung disease
obstructive, restrictive
Describe obstructive lung disease
reduction in flow through airways
Describe restrictive lung disease
reduction in lung expansion, inability of lungs to expand
What is a common feature of restrictive and obstructive disease
reduce ventilation
What is FEV1
forced expiratory volume in one second
What can cause obstructive lung disease
narrowing airways
What causes the narrowing of airways in obstructive lung disease
excess secretion, bronchoconstriction, inflammation, increased air flow resistance
What is the effect on FEV1, FVC in obstructive lung disease
FVC is the same, FEV1 and FEV1% decrease
Name some obstructive lung diseases
asthma, COPD, emphysema, chronic bronchitis cough
What type of disease is asthma
inflammatory disease
What is over stimulated in asthma
muscarinic receptors in airways
What happens in asthma
inflammatory cells release inflammatory mediators into airways causing bronchoconstriction
Example of an inflammatory mediator
histamine
What is a atopic trigger for asthma
extrinsic - allergies
What is a non-atopic trigger for asthma
intrinsic - respiratory infections, cold, irritants
What is the short term treatment for asthma
salbutamol
What is salbutamol
short acting B2 adrenoreceptor agonist
What does salbutamol cause
dilation of airways
What is a long acting treatment for asthma
beclometasone, long acting B-adrenoreceptor agonists
What is beclometasone
inhaled steroid - glucocorticoids
What is the effect of beclometasone
reduces inflammatory response
What are the two main characteristics of restrictive lung disease
reduced chest expansion, loss of compliance - fibrosis
Describe the features of loss of compliance in restrictive lung disease
increased collagen, decreased vital capacity, normal ageing process
What is the effect on FEV1, FVC in restrictive lung disease
FVC is reduced, FEV1% is the same or increases
TRUE or FALSE - peak flow increases in restrictive lung disease
FALSE
Describe asbestosis
slow build up of fibrosis tissue - loss of compliance - fibres trapped in lungs
What disease is a mixture of obstructive and restrictive
emphysema
Where is the basic respiratory rhythm generated
centres in the medulla
What are the medullary centres
dorsal respiratory group, ventral respiratory group
What does the dorsal respiratory group control
inspiration
How do the dorsal respiratory group control inspiration
sends signals to inspiratory muscles
Describe the activity of the dorsal respiratory group
spontaneously active
What does the ventral respiratory group control
inspiration, expiration
Describe the activity of the ventral respiratory group
inactive during quiet respiration
What does the ventral respiratory group control during activation
forceful inspiration and expiration
What does the pneumotaxic centre control
increases rate by shortening inspirations
What does the pneumotaxic centre have an inhibitory effect on
inspiration centre
What is the function of the apneustic centre
increases depth, reduces rate, prolongs inspirations
What does the apneustic centre stimulate
inspiratory centre
What reflex uses stretch receptors in the lungs
Hering-Breuer reflex
Describe the Hering-Breuer reflex
stretch receptors send signals to medulla to limit inspiration
What does the Hering-Breuer reflex prevent
over-inflation of the lungs
What do central chemoreceptors monitor
conditions in cerebrospinal fluid, sense CO2 and pH
What is the response to rise in CO2
increased ventilation
Where are peripheral chemoreceptors located
carotid body, aortic arch
What do peripheral chemoreceptors respond to
increased CO2, decreased pH, oxygen
What does stimulation of peripheral chemoreceptors cause
increased ventilation
