Cardiopulm Changes w/ Aging Flashcards
What happens in the cycle of impaired aerobic capacity in older adults?
Reduced physical activity → Deconditioning → Decreased aerobic capacity → Increased fatigue → Further inactivity
What happens to the left ventricle with aging?
Concentric hypertrophy, reduced compliance, smaller chamber size, increased workload on LA, and reduced LV contractility
What changes occur in the left atria with aging?
Increased chamber diameter & atrial hypertrophy
What age-related changes occur in the heart’s conduction system?
Collagen deposition, fatty tissue, fibrosis inhibit signal transmission → Increased risk of arrhythmias
By what age does the SA node have <10% of its pacemaker cells remaining?
Age 75
What is the main reason for reduced cardiac output in older adults?
Reduced stroke volume due to ventricular stiffness & decreased HR
What is diastolic dysfunction in aging?
Reduced ventricular compliance leading to impaired filling
How does blood oxygen saturation change with aging?
Oxygen loading in the lungs is altered after age 85 → Reduced oxygen saturation
Why is oxygen diffusion slower in older adults?
Less time for oxygen loading at the alveolar-capillary interface
What is the hallmark of aging in terms of aerobic capacity?
Decline in VO2peak (maximal aerobic capacity)
How does VO2max decline with age?
3-6% per decade in 30s-40s → >20% per decade after age 70
What physiologic changes contribute to hypertension in aging?
Declining baroreceptor function, catecholamine/neural declines, and vascular stiffening
What are key anatomic changes in the aging cardiovascular system?
Loss of SA node cells, reduced vascular compliance, thickened capillary basement membrane
What are the clinical consequences of these changes?
Slower HR, higher BP, reduced cardiac output, reduced exercise capacity
What structural lung changes occur with aging?
Decreased alveolar integrity → Larger airspaces → Obstructive-like dysfunction
What happens to mucous clearance with aging?
Decreased cough strength & reduced mucociliary clearance
How does the chest wall change with aging?
Reduced thoracic vertebral height, rib cage calcification, kyphosis → Reduced compliance
What happens to respiratory muscles with aging?
Reduced diaphragmatic strength, muscle atrophy, loss of fast-twitch fibers
How does FEV1 decline with age?
25-30mL/year after age 35-40 → 60mL/year after age 70
Why does lung function decline with age?
Increased residual volume, decreased tidal volume, reduced elasticity & recoil
What are the main pulmonary changes with aging?
Decreased lung elasticity, tidal volume, and cilia function; increased airway resistance
How do musculoskeletal changes affect breathing in older adults?
Increased AP chest diameter, rib cage rigidity, thoracic curvature, weaker respiratory muscles
