Drive - ageing lung Flashcards
What is problematic about a delayed response to hypercapnia and hypoxia?
Increased vulnerability to ventilatory failure
Why may older people experience impaired gas exchange? (11!)
Due to changes in the shape of thorax
Costal cartilage becoming stiffer
Respiratory muscle decreases in mass
Reduction in fast-fatigue resistant fibres
Denervation of muscle fibres
Loss of elastic recoil in lungs
Degeneration (or ruptures) in elastin fibres in alveoli and respiratory bronchioles
Ventilation-perfusion mismatch increases
Reduction in alveolar surface area
Reduced lung capillary and blood flow
Oxygen saturation of haemoglobin declines (seen in times of demand)
Why may older people experience decreased immune system function? (3)
Number of glandular epithelia cell decrease (less protective mucus)
Decreased sputum clearance
Less effective mucocilary system
