GERIATRICS Flashcards
What two important changes in the autonomic nervous system (ANS) take place with aging?
A decrease in response to Beta- receptor stimulation and an increase in sympathetic nervous system activity.
Why do geriatric patients have a decrease response to beta antagonists?
In the geriatric patient, the beta receptor has a reduced affinity for beta adrenergic receptors antagonists. Beta-adrenergic receptor agonists also show a reduced affinity for the beta-adrenergic receptor in the elderly.
An elderly patient is supine. This position changes to sitting or standing. Blood pressure decreases but heart rate remains unchanged. Why?
Gravity causes blood to pool in dependent extremities when going from the recumbent to the sitting or standing position. Heart rate does not change because autonomic responses that maintain cardiovascular and metabolic homeostasis are progressively impaired in the elderly. known as AUTONOMIC DYSFUNCTION
What is the most significant risk factor for developing cancer?
Old age
1 MET is equal to
3.5 mLO2/kg/min
2 questions to assess cardiac status
Can you walk up a flight of steps without stopping?
Are you able to walk 4 blocks without stopping?
When does physiologic function begins to wane?
As early as 30
Walking 2 blocks slowly is how many mets?
2
How do you calculate metabolic equivalent?
Metabolic rate of specific physical activity / metabolic rate at rest.
What happens to the response to hypercarbia and hypoxia in elderly
Decrease
because the central, carotid and aortic chemoreceptors are less sensitive to alternations in pH, PaCo2, PaO2 leading to increase risk for respiratory failure.
What happens to protective airway reflexes an upper airway tone in the elderly?
Decreased
Lung elasticity in the elderly is
Decreased
What happens with RV in the older patient?
Increased
Closing capacity surpasses FRC at ____in the supine and ______when standing
45 sit; 65 stand (At 45 you sit and listen at 65 you stand and raise hell)
Why does the TLC remains unchanged in the elderly?
IBecause of the increase in RV and reduction in VC
3 main respiratory changes in the elderly the increase? FRC
FRC
RV
Closing capacity
Main respiratory changes in the elderly the decrease?
Decrease Vital capacity
FEV & FEV 1 in the elderly
Decrease (loss of lung elastic recoil favors airway collapse during forced exhalation)
Most common coexisting disease in the elderly
Cardiac disease
4 most common condition in the elderly
HTN
CAD
CHF
MI
What is the best indicator of cardiac Reserve?
Exercise tolerance
Ability to perform physical ADLs
What is the most common cause of death in the postop period?
MI
What happens to collagen in the elderly ? What about elastin?
Collagen INCREASES
Elastin is lost
What happens to arterial compliance and venous compliane?
They are both decrease
Arterial compliance decreases , what does that cause?
increase SVR and afterload
Venous compliance decreases , what does that cause?
Changes in blood volume cause drastic changes in preload.
What happens to BP with aging?
Increase
Systolic FUCTION in the elderly***
NO CHANGE
How is Maximal HR is calculated
220 - age
SV in the elderly
Diminish ability to increase SV
Heart, SV and CO in the elderly
Decrease
What happens to the circulation time with the elderly? why?
Decrease; decreased CO
ANS : What process is associated with the NORMAL aging process
Autonomic dysfunction
NE concentration in the plasma, SNS tone?
Higher NE concentration in the plasma
Elderly response to catecholamines
Decrease
Autonomic function in the elderly is
Decrease
Few things that increase risk of hypothermia?
Shivering increases VO2
Increased blood loss
impaired drug metabolism
Vasoconstriction increase afterload.
MAC and aging: % and age
MAC decreases 6% for every decade after 40
IV induction dosage with the elderly
Doses should be reduced 30-40%
Alzheimer’s disease is a disease associated with
decrease Act
Parkinson’s disease is a disease associated with
Decrease dopamine in the BASAL GANGLIA
Brain mass and aging
Reduced but does not affect mental capacity
Most common CNS complication in the elderly during preoperative period?
Postoperative Delirium
Postoperative delirium vs Postoperative cognitive dysfunction onset
Delirium - Early onset
POCD- Wks to months after surgery.
Postoperative delirium vs Postoperative cognitive dysfunction Presentation
Delirium - Easy to identify (disordered behavior, perception, memory, psychomotor skills.
POCD: Subtle and difficult to pinpoint (impaired concentration , comprehension , psychomotor skills)
Risk FACTORS of POST Op Delirium:
DELIRIUM
Drugs (anesthetic agents) Electrolyte imbalance Lack of drugs (Withdrawal) Infection Reduced sensory input Intracranial dysfunction Urinary retention and fecal impaction Myocardial event, male gender
What is the most important risk factor for POCD?
Advanced Age
What is the top 3 risk factors for Post operative cognitive dysfunction?
Advanced age
pre-existing cognitive deficit
cardiac surgery
Long duration surgery
Treatment of delirium vs treatment of POCD?
Delirium Treatment: Treat underlying cause, antipsychotics , minimize polypharmacy
POCD: no specific treatment, mild cases resolve in about 3 months.
Elderly and sensitivity of nerve tissue to LA
Increased
Sensitivity of elderly to intrathecal anesthetics
Decrease CSF volume –> greater spread of LA so decrease the dose.
Sensitivity of elderly to epidural anesthetics
Decrease epidural space volume –> greater spread of LA so decrease the dose.
Serum creatinine level in the elderly ***
NO CHANGE
Na+ handling and the elderly
Na+ handling is impaired.
GFR and aging
GFR decreases with age
Creatinine does NOT CHANGE in elderly why?
GFR decreases, which should cause an increase in creatinine. But muscle mass decreases with age and that means less creatinine is produced. The 2 processes cancel each other out.
What is POOR indicator of renal function in the elderly?
Serum Cr.
What happens to Creatinine clearance in the elderlY?
Decreased
What is the most sensitive indictor of renal function and drug clearance in the elderly>
Creatinine Clearance
Renal mass in the elderly and its impact?
Loss of mass = loss of functioning glomeruli = loss of nephrons.
GFR decrease with aging, what is the rate
Decrease by 1 ml/min/year after age 40
Elimination of hydrophillic drugs and elderly
Decrease elimination of hydrophilic drugs
Elimination of hydrophillic drugs metabolites and elderly
decrease
At what age should you consider dosage adjustments
Age > 60
Aldosterone in the elderly; response to acid load in the elderly
Both Decrease
ADH in the elderly
Decrease, surgical stress increase ADH but the elderly have a reduced response to ADH.
Hepatocellular function in the elderly is
NORMAL no changes
Hepatic Mass in the elderly and its impact
Less hepatic mass = less total enzyme produced.
Hepatic blood flow in the elderly and its impact
Decrease meaning that less drug or toxin is delivered to the liver per unit of time.
Preoperative hepatic function of the elderly>
Reduced as a RESULT OF DECREASE BLOOD FLOW AnD LIVER MASS not because of impaired hepatocellular function .
Alpha 1 acid glycoprotein production in the elderly is
Increased
Albumin production in the elderly is
Decreased
Pseudocholinesterase production is _____What is the significance of that?
Decreased
Prolonged duration of succinylcholine and ester LA.
Phase I reactions in the elderly is ______and phase II reactions are
Decrease; no change in phase 2 reactions
First pass metabolism in the elderly and its significance?
Due to reduced hepatic mass and liver blood flow
Increase concentration of drugs with HIGH PASS metabolism
Decrease concentration of drugs that require LIVER FOR ACTIVATION.
Circulation time in the elderly is decreased; how does that affect IV induction and inhalation induction?
IV induction slowed
Inhaled induction fast
Surface area to body mass ratio in the elderly?
Reduced lean body mass
Total body fat in the elderly
Increased Vd of lipophilic drugs -> larger reservoir prolong their elimination
Free fraction of drugs that binds to albumin (acidic drugs) is
InCREASED
Free fraction of drugs that binds to basic drugs is s
DECREASED
Why is the rate of recovery for volatile anesthetic decrease in the elderly?
Increased total body fat
Decreased gas exchanged
Decrease hepatic metabolism
In the elderly, the decrease in Beta-receptor responsiveness is secondary to both
decreased receptor affinity and alterations in signal transduction
In the elderly patient, total body water ______while total body fat ______
decreases ; increases.
Thus, the volume of distribution for water-soluble drugs such as glycopyrrolate, succinylcholine, and gentamicin
decreases
While the volume of distribution for lipid-soluble drugs such as barbiturates, benzodiazepines, and volatile anesthetics
increases.
The duration of action of midazolam is increased in the elderly. The clearance of the drug is reduced by as much as
30 percent due to a decrease in hepatic mass and perfusion.
The duration of action of midazolam is _____ in the elderly.
increased
Liver and kidney function in the elderly
Decreased renal function and decreased hepatic function
Hepatic function in the elderly is
decreased
Write an equation that shows how the Pa02can be estimated for a given age. Predict the Pa02 of a 78-year-old patient
Pa02 =102-Age/3.
How does the arterial blood-alveolar partial pressure C02 difference (Pa- COrPAC02) change with age? Why?
Increase in V/Q mismatching with age.
Will muscle relaxants that are eliminated by renal or hepatic mechanisms have a shortened or prolonged elimination half· life in the geriatric patient?
Prolonged, because ofreduced renal and hepatic function
About the postoperative fluid status of an elderly patient with a history of congestive heart failure. On what postoperative day would you expect third space fluid to mobilize into the vascular system?
Day 2 . Third-space fluid begins to mobilize into the vascular space on postoperative day two. It is important to evaluate the elderly patient for signs of fluid volume excess such as rales, crackles, tachypnea, and orthopnea.
Elderly signs of fluid volume excess
Rales, crackles, tachypnea, and orthopnea.
The decrease in total body water that occurs with aging is primarily due to
A decrease in muscle mass
Which of the following alterations would you expect to see in a patient treated with acetylcholinesterase inhibitors for Alzheimer’s disease?
They will exhibit a resistance to nondepolarizing muscle relaxants due to the use of acetylcholinesterase inhibiting drugs as part of their medical management. They will also exhibit a longer duration of action with succinylcholine.
What primarily explains the prolonged duration of midazolam in an elderly patient?
decreased hepatic perfusion
By age 80, the number of functioning nephrons has decreased by. Bone density decreases significantly with age, increasing the risk for fractures. Although hepatic mass decreases significantly, baseline hepatic function remains well preserved with age.
50 percent
Lean muscle mass and aging
decreases with age
With age, renal cortical mass decreases by as much as
Renal cortex lowers by 20-25 percent with age.