respiration 3 Flashcards
what are the 2 types of ling disease?
obstructive
restrictive
what is obstructive lung disease?
where there is reduction in flow through airways
(e.g.asthma)
(increased resistance)
what is restrictive lung disease?
reduction in lung expansion
e.g. fibrosis, asbestosis
what do obstructive and restrictive lung disease both do?
reduce ventilation
in obstructive lung disease what can cause airway narrowing?
excess secretions inflammatory response (histamine) bronchoconstriction (e.g. asthma)
what happens to FEV1 and FVC in OLD?
FVC is usually unaltered
FEV1 decreases
(initial flow and peak flow similar)
how does flow-volume loop change in OLD?
initial and peak flow rate are similar but there is a sharp fall in flow rate after peak CONCAVE SHAPE to curve
give some examples of OLD
asthma, chronic bronchitis(persistant cough+++musous secretion), emphysema, chronic obstructive pulmonary disease
what factors can trigger asthma?
ATOPIC(extrinsic) - allergies
NON-ATOPIC(instrinsic) - stress, cold air, infection, excercise
what is asthma response?
movement of inflammatory cells to airways , release of inflammatory mediators (histamine), this causes bronchoconstriction
what can treat asthma?
salbutamol (short acting B2 agonist)(acts like adrenaline)
- cause dilation
inhaled steroids (glucoticoids) (long acting B2 agonsit)
- can reduce inflammatory response
what can reduction in chest expansion be caused by?
in RLD
chest wall abnormalities, muscle contraction deficiency
what can cause loss in compliance?
aging, increase in collagen, exposure to environmental factors
what happens to FVC and FEV1 in restrictive lung disease?
FVC decreases but FEV1% can remain unaltered/increase,
what happens to flow volume loop in RLD?
shape is normal but reductions in peak and volumes of air moved
what happens in asbestosis?
cells recognised as foreign - inflammatory response.
build up of fibrous tissue - loss of compliance
RESTRICTIVE
what is breathing pattern generated by?
centers in medulla
how can breathing be altered consciously?
holding breath, hyperventilation
what are 2 respiratory groups and what do they do?
dorsal respiratory group (DRG)
-controls inspiration + send signals to inspir muscles
-spontaneously active
ventral respiratory group (VRG)
- controls inspiration and expiration
-inactive during quiet respiration - activation helps control forceful activiation.
how does PONS control respiration?
controls rate and depth of breathing
pneumotoxic(-) and apneustic(+) centres
what do PONS pneumotoxic (-) and apneustic (+) centres do?
pneumotoxic(-)
-increases rate by shortening inspirations
-inhibitary effect on inspititary centre
apneustic (+)
-reducing breathing rate by increases depth+prolonging inspiration
-stimulates respiratory centre
what is hering-bear reflex?
stretch receptors in lung send signals back to medulla to limit inspiration and prevent overinflation of lungs
