Geriatric Flashcards
What year will 20% of the population be greater than 65 years old.
2030
What percentage of people older than 60yo will experience memory decline? How can we prevent it?
40%
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What structural changes occur in the brain as a part of aging?
Cerebral atrophy, decreased gray matter (neuronal shrinkage not loss), and decreased white matter (increased in ventricular size and progressive loss of memory, balance, and mobility).
Animal studies have shown a decrease in which neurotransmitters as age progresses?
Which NT stays the same?
Dopamine, ACh, norepi, serotonin
No change in glutamate.
What 4 reasons do elderly patients require less neuraxial anesthesia?
- Decreased epidural space
- increased permeability of dura
- decreased volume of CSF
- decreased diameter/number of myelinated fibers in dorsal and ventral nerve roots
How does the peripheral nervous system change as we age?
- Inter-schwann cell distance (node of ranvier) distance decreases.
- conduction velocity decreases
What cardiac (heart only) changes occur as we age?
- Myocyte # decreases
- left ventricle wall thickens.
- SA node cells decrease
- conduction velocity decreases
- aortic valve thickens and calcifies.
- decreased contractility
- increased ventricular stiffness
- higher filling pressures
- less beta adrenergic sensitivity
What usually causes age related left ventricular wall thickness to increase?
Hypertension over time
What happens when we lose SA node cells?
We are more susceptible to tachy and brady arrhythmias
What does less beta-adrenergic sensitivity cause?
Decreased maximal heart rate and EF during stress
Basically the SNS can’t kick Off the fight or flight response to maintain CO through tachycardia when things like aesthetics drop their blood pressure.
Why do blood vessels get stiff as they age?
Breakdown of collagen & elastin
Less endogenous NO release
Early wave deflection (increased afterload, diastolic dysfunction)
What structural changes occur in the lungs as we age?
- Loss of elastic recoil and loss of surfactant
- increased lung compliance
- Enlarged bronchioles and alveolar ducts
- loss of vertebral height and calcification of vertebra
What changes in lung capacities/volume/breathing when we have enlarged bronchioles and alveolar ducts?
Early collapse of small airways during exhalation.
We have increased anatomic dead space, increased closing capacity, and impaired gas exchange
What is closing capacity?
The amount of air left in the lungs when the small airways start to close off.
What physiologic changes occur with loss of vertebral height and calcification of vertebra?
- Barrel chest
- Diaphragmatic flattening
- Chest wall stiffness leading to increased work of breathing.
What lung volumes/capacities change as we age? Which stay the same?
Change:
- decreased vital capacity
- increased closing capacity
- increased residual volume
Same: total lung capacity
How much does your FEV1 change as you age?
Decreases by 6-8% per decade
What effects does weaker pharyngeal muscles have?
- Decreased clearance of secretions
- less efficient coughing
- decreased esophageal motility
- less protective upper airway reflexes
How does V/Q mismatch change with age?
FRC increases slightly while closing capacity increases a lot. This causes increased shunting leading to decline in arterial oxygenation.
This is the most important MOA for alveolar-arterial oxygen gradient.
How much does GFR decrease as we age?
1 ml/min/m2 per year after the age of 30
What renal changes occur as we age?
Decreased GFR, blunted response to aldosterone, vasopressin, and renin leading to trouble adjusting fluid and electrolytes
Also retention and UTI’s are more common.
What types of hepatic metabolism decline as we age?
Phase 1 metabolism: oxidation, reduction, hydrolysis via CYP450 enzymes.
What types of hepatic metabolism do not change as we age?
Phase 2: acetylation and conjugation
What PONV medications should we avoid in elderly patients?
Prochlorperazine, promethazine, metoclopramide
