Geriatrics Exam 3 Flashcards
What marks the beginning of the aging process, and what are its eventual outcomes?
- Begins with birth
- Includes gradual organ impairments
- Ends with death
How much has the geriatric population increased in the last 50 years?
Increased 300%.
At what age does an individual qualify as elderly?
65 years or older.
At what age do our physiological functions peak before they start to decline?
Peak at 30, then decline.
Does aging itself pose a surgical risk?
- No
- Anatomic and physiologic changes associated with aging determine patient outcomes.
How does aging affect tolerance to changes or restoration of homeostasis?
- Makes individuals less tolerant to changes or restoration of homeostasis
- When exposed to disease, trauma, or surgical stress.
What factors increase the risk of perioperative complications in the elderly?
- Progressive decline of baseline functions
- Age-related comorbidities
- Increased ASA physical status.
How are patients 65 years of age or older classified?
As geriatric or elderly.
What tool is needed for measuring functional reserve in geriatric patients?
A bedside tool that measures metabolic equivalents (METs).
What is the oxygen consumption rate equivalent to one MET?
3.5 mL O2/kg/min.
What MET level is associated with increased perioperative risk?
Inability to achieve 4 METs.
Can you give examples of activities that meet the 4 METs level?
- Climbing a flight of stairs without stopping
- Raking leaves.
Why might METs be considered a poor predictor of postoperative morbidity and mortality?
- Due to their subjective nature
- Duke Activity Status Index (DASI) may be better for functional evaluation
How is frailty characterized in geriatric patients?
- By decreased reserve and reduced resistance to stress
- Leading to poorer outcomes when exposed to perioperative stressors
What is the most common coexisting disease in the elderly, and what are the four most common conditions?
Cardiac diseases
- Hypertension
- Coronary artery disease (CAD)
- Congestive heart failure (CHF)
- Myocardial ischemia
What are the best indicators of cardiac reserve in the elderly?
- Exercise tolerance
- Ability to perform daily living activities.
What happens to arterial compliance in the elderly?
Decreased
What happens to venous compliance in the elderly?
Decreased
How does myocardial compliance change in the elderly?
Decreased
What happens to conduction in the cardiovascular system of the elderly?
Decreased
What change occurs in myocardial mass in the elderly?
Increased
What happens to lung elastic recoil and residual volume with aging?
- Reduced recoil
- Increases residual volume (RV)
What is Residual Volume (RV)
The volume that remains in the lungs after a full exhalation
Why do the elderly’s small airways collapse during expiration?
Reduced elastic recoil.
When does closing capacity surpass FRC, and its effects?
- At ~45 years (supine)
- ~65 years (standing)
- Leading to V/Q mismatch and reduced PaO2.
Small airway collapse during tidal breathing sets the stage for:
- V/Q mismatch
- Increased anatomic dead space
- Reduction in PaO2
What factors reduce vital capacity in the elderly?
- Reduced recoil
- Increased chest stiffness
- Weaker muscles
How does aging affect total lung capacity?
- Remains unchanged
- Due to increased RV balancing, reduced VC.
What are the Key Pulmonary changes that Increase in the elderly?
- Minute ventilation
- Lung compliance
- FRC
- Closing Capacity
- Residual volume
What is the only pulmonary function that has no change in the elderly?
Total lung capacity
What is lung compliance?
Increase volume for a given increased pressure
What are the consequences of small airway collapse in the elderly?
- Increased Dead space
- Increased V/Q mismatch
- A-a gradient
- Decreased Alveolar surface area
- Decrease PaO2
An aged lung tissue has high compliance, but it has:
It’s easy to inflate
Low Elasticity
Its harder for it to return to its original shape
How is the FRC determined?
- The balance between lung elestic recoil
- Chest wall complaince
Why is the kidney’s function important?
- Regulates intravascular volume
- Electrolytes
- Acid/base balance
- Plasma drug concentrations
What effect does a reduction in renal reserve have?
Well tolerated in healthy patients but risky with surgery or disease due to impaired homeostasis maintenance.
What is the risk associated with perioperative renal failure?
Very high mortality.
Why is perioperative fluid management critical?
- Prevents fluid overload and dehydration
- Due to impaired sodium handling
- Urine concentration/dilution capacity
How does reduced venous compliance affect the elderly?
Impairs venous circulation’s reservoir function.
The Kidneys have difficulty in correcting the following in the elderly:
- Correcting electrolyte imbalances
- Titrating excess non-volatile acids
The kidneys have the ability to regulate:
- Intravascular volume
- Electrolytes
- Acid/base balance
- Plasma drug concentration
What endocrine changes lead to diabetes in the elderly?
- Decreased pancreatic beta cell number/function
- Decreased insulin secretion
- Insulin resistance
- Increased hepatic glucose release
- Impaired fat/protein breakdown
How does diabetes affect perioperative and postoperative risks?
Increases risks due to complications like:
- Microvascular disease
- Hypertension
- Cardiovascular disease
- Especially in patients with a history of diabetes for 10+ years
What cognitive issues are associated with diabetes?
- Development of cognition issues
- Alzheimer’s dementia
What factors should be assessed in diabetic patients preoperatively?
- HGB A1C
- Length of disease
- Medications
- Complications from diabetes
How does MAC change with age?
Decreases by 6% per decade after age 40.
What happens to neurotransmitter activity in the brain with aging?
Decreased.
How does aging affect brain mass?
Decreased.
What changes occur in peripheral nerves with aging?
Quantity and function decrease.
What is the most common perioperative CNS complication in the elderly?
Postoperative delirium.
When does postoperative delirium and cognitive dysfunction typically occur?
- Delirium: early postoperative period
- Cognitive dysfunction: weeks to months after surgery
How is postoperative delirium treated?
- Reversing underlying cause
- Antipsychotics
- Minimizing polypharmacy
Is there a specific treatment for postoperative cognitive dysfunction (POCD)?
- No specific treatment
- Most cases are mild and tend to resolve after about 3 months.
What causes a decreased basal metabolic rate in the elderly?
- Decreased physical activity
- Decreases in testosterone levels
- Decrease growth hormone levels
By age 80, what percentage of skeletal mass is lost?
- 50%
- Causing significant loss of body protein
- Alterations in carrier proteins
What increases the elderly’s susceptibility to skin tears and nerve injuries?
Loss of collagen and elastin.
Where does body fat increase in the elderly?
- In the viscera
- Subcutaneous abdominal area
- Intramuscular area
- Hepatic areas
What happens to total body water and blood volume by age 75?
- Decrease in total body water
- Blood volume decreases 20%-30%
- Increasing the risk of hypotension
- poor compensation for postural changes
What body composition changes affect thermoregulation in the elderly?
- Loss of lean body mass
- Increased total body fat
- Decreased metabolic rate
- Decreased total body water
How do age-related changes make the elderly vulnerable?
- They become more vulnerable to hypotension and postural changes
- With a reduction in blood volume of 20%-30%.
What contributes to impaired thermoregulation in the elderly?
- Decreased function of the hypothalamus
- Leading to more pronounced and longer-lasting hypothermia
- Lower basal metabolic rate
- High ratio of surface area to body mass
- Less effective peripheral vasoconstriction in response to cold
How does hypothermia affect anesthetic elimination?
Slows anesthetic elimination.
What is the impact of hypothermia on recovery from anesthesia?
Prolongs recovery.
How does hypothermia affect coagulation?
Impairs coagulation.
What does hypothermia increase the chance of in patients?
Increases the chance the patient will shiver.
How does shivering affect the body, and what are its consequences?
- Increases oxygen consumption by 400%
- Leading to hypoxia
- Acidosis
- Cardiac compromise
What are the Key Cardiovascular Changes in the Elderly?
- Decreased Arterial Compliance
- Decreased Venous compliance
- Decreased Myocardial compliance
- Decreased Conduction
- Increased Myocardial mass
A stiffer chest wall reduces the tendency of the chest to:
Expand
Why is Vital Capacity Decreased with the Elderly?
- Increase chest wall stiffness
- Decrease elastic recoil
- Decrease muscle strenght
Factors that predispose a patient to fluid overload/Dehydration:
- Impairment of Na+
- Ability to concentrate urine
- Capacity to dilute urine
Venous capacity is reduced in the elderly and affects the ability of:
Venous circulation to function as a Reservoir
How much does Renal Blood Flow decreases per decade?
10%
How is the serum creatine affected in the elderly?
Does NOT change!
GFR decreases with age!
Is Serum creatine an indicator of renal function in the elderly?
NO, its a poor indicator
What is the most sensitive indicator of renal function in the elderly?
Creatinine Clearance
What is the GFR rate in the adult male?
~ 125 mL/min
How much does GFR decreases after age of 40?
Decreases 1 mL/min/year
What are the consequences of a decrease GFR?
- Increased risk for fluid overload
- Decrease elimination of hydrophilic drugs
- Decrease elimination of hydrophilic metabolites of lipophillic drugs
Consider dose adjustment if > 60 Yr.
