Geriatrics Flashcards
One MET is equivalent to what O2 consumption?
3.5 mL O2/kg/min
For every MET a pt can achieve, mortality decreases by what percent?
11%
Is minute ventilation increased or decreased an why?
- Increased
- increased dead space necessitates an increased minute volume to maintain normal PaCO2
Due to a decrease in lung elasticity, what else does this affect?
- inc. dead space
- dec. alveolar surface area
- inc. V/Q mismatch
- inc. A-a gradient
- dec. PaO2
- dec. in lung elasticity also support gas trapping, which explains the increase in RV
Is chest wall compliance increased or decreased and why?
- Decreased
- b/c there is inc. calcification of joints, inc. diaphragmatic flattening, inc. A:P diameter, dec. vetebral disc height, dec. resp muscle strength, dec. lung elastic recoil
Is there an increased or decreased response to hypercarbia and hypoxia and why?
- Decreased
- chemoreceptors are less sensitive to changes in pH, PaCO2, and PaO2
- leads to inc. risk of hypoventilation, apnea, and resp failure
- consider CPAP or BiPAP for at risk pts
Are protective reflexes increased or decreased and why?
- Decreased
- reduced efficiency of cough and swallowing
Is upper airway tone increased or decreased?
- Decreased
- Decreased respiratory muscle strength
- inc. risk for resp failure and upper airway obstruction
Is lung compliance increased or decreased?
- increased
At what age dose closing capacity surpass FRC?
- 45 yrs supine
- 65 yrs standing
What is the most common coexisting disease in the elderly?
- cardiac disease
- 4 most common = HTN, CAD, CHF, myocardial ischemia
In the postop period, what is the most common cause of death in the elderly?
MI
What CV function is unchanged in elderly?
Systolic function
What is the most sensitive indicator of renal function and drug clearance in the elderly?
Creatinine Clearance
Which renal factor is unchanged in the geriatric population?
Serum Creatinine
