Test 2: Geriatrics (pt 2/3) Flashcards
Older adults have a decrease in GFR of roughly _____ to ____%, secondary to what?
25-50% decline secondary to atrophy of kidney parenchymal tissues, deterioration of renal vascular structures, decreased renal mass, and decreased renal blood flow.
Due to their decreased GFR, renal patients are at risk for what?
1) Fluid overload
2) Accumulation of metabolites and drugs that are excreted by the kidneys
3) Decreased drug elimination (prolonged effects of a wide range of anesthetic drugs and adjuncts)
4) Electrolyte imbalances (risk of arrhythmias)
5) Dehydration
Serum creatinine is _____ if there is no renal failure because of decreased creatinine production from the overall declining skeletal muscle mass associated with aging.
Unchanged.
What is the best indicator of drug clearance?
Creatinine clearance
Why are the elderly at high risk for CKD?
1) Coexisting diseases (HTN, CVD, DM, COPD)
2) Frailty
3) Complex Medical Regimens & Polypharmacy
The aging adult liver decreases in mass by approximately ____ to ____% and may be attributed to the ______ in its blood flow.
20% to 40%; decrease
What affects on drug metabolism and protein binding are seen with age related hepatic changes?
1) Decreased drug metabolism, prolonged 1/2 life, and inc/dec distribution of medications
2) Serum albumin decreases & Alpha-1 acid glycoprotein (AA) Increases
Albumin primarily binds what kind of drugs?
Acidic drugs - like Benzos and Opioids
Alpha-1 Acid Glycoprotein (AAG) binds what kind of drugs?
Basic drugs - like Local Anesthetics
Due to aging, there is a _____ in number and function of the pancreatic islet beta cells that results in _______ insulin secretion.
decline; decreased
Why are the elderly more likely to be glucose tolerant or diabetic?
Insulin resistance occurs peripherally, which contributes to increased hepatic production of glucose and impaired breakdown of fats and proteins.
Peripheral Insulin Resistance (DM) increases the risk for what?
-CVD & HTN
-Periop and postop complications (CVA, MI, Ketoacidosis, Infection)
-Compromise in one or more organ systems
Why is there a decrease in the basal metabolic rate (BMR) as a result of aging?
-Decreased physical activity
-Decreases in testosterone & Growth Hormone
Decreased BMR has an effect on muscle mass and thermoregulation.
Skeletal muscle mass and strength declines with aging with _____% of skeletal mass being lost by the age of 80 years.
50%
Why is there a significant loss in body protein associated with aging?
-decrease in skeletal muscle mass
-alterations in carrier proteins (e.g., albumin and AAG).
Increased body fat with the aging adult is distributed where?
-Viscera
-Subcutaneous abdomen
-Intramuscular
-Intrahepatic
What are skin changes associated with aging?
-Decreased dermal and epidermal thickness of the skin (loss of collagen & elastin)
-Decrease in subcut fat and thinning of skin make them prone to skin tears and nerve injuries
Blood volume decreases approximately ____ to ____% by age 75 years.
20-30%
Older adults are more vulnerable to what as a result of the decrease in TBW?
Hypotension; difficulty compensating for position changes
Decreased function of the hypothalamus causes what?
Impairment of thermoregulation
Why is hypothermia more pronounced and lasts longer in the elderly?
-Lower BMR
-High ratio of surface to body area mass
-Less effective peripheral vasoconstriction in response to cold
Why is hypothermia particularly detrimental in the elderly patient?
-Slows anesthetic elimination
-Prolongs recovery from anesthesia
-Impairs coagulation
-Impairs immune function
-Blunts the ventilatory response to CO2
-Increased shivering (which increases O2 consumption, leading to hypoxia, acidosis, and cardiac compromise)
Older adults produce less heat per kg of body weight, predisposing them to what?
Being unable to maintain their heat in cool environments, and making it more difficult to restore a normal body temperature once they are hypothermic.
What are the methods of maintaining normothermia?
-Prevention of heat loss
-Active warming methods
-Warm IVF/blood products
-Forced air warming devices
-HME (environmental humidity higher than 50%)
Age-related physiologic changes of the central nervous system (CNS) are characterized by what?
-a progressive loss of neurons and neuronal substance
-decreased neurotransmitter activity
-decreased number of myelinated nerve fibers
-decreased brain volume
Where are these CNS losses most prominent?
Cerebral cortex, particularly the frontal lobe
What do these CNS losses cause?
Changes in mood, memory, and motor function
Why are older patients more sensitive to CNS depressants and anesthetic agents (General anesthetics, hypnotics, opioids, and benzos)?
-Number of available receptors is decreased
-Blood-Brain Barrier is more permeable (also contributes to neurocognitive disorders such as Alzheimer’s Dz)
The dose of induction agents should be decreased by as much as ____% in older patients, arguing for very meticulous titration.
50%
Why should Benzodiazepines be avoided in older adults?
They contribute to adverse events (i.e., falls, confusion, POD).
BIS <___ has an increase in M/M in geriatric population
40
Why would BIS monitoring be beneficial in the elderly?
-To guide titration of anesthesia and speed recovery times
-To decrease the incidence of postop delirium and cognitive dysfunction
What are anatomic changes in the elderly that put them at risk for complications with Neuraxial anesthesia?
-Decreased # of myelinated nerve fibers (risk for nerve damage)
-Decreased intervertebral disc height, narrowing of the intervertebral foramina, decreased space between the posterior spinous processes, presence of calcifications, and changes in lordosis.
-Dura is more permeable to local anesthetics
-CSF spec grav increases, and its volume decreases
What are the dosing recommendations r/t neuraxial anesthesia in the older adult?
-Alterations in the nervous system may produce a more enhanced spread of local anesthetics for subarachnoid blocks
-Decreased dose of local anesthetics is recommended for subarachnoid and epidural blockade
Are subarachnoid and epidural blocks contraindicated in the elderly patient?
No, but weigh pros/cons.
What are the overall CNS changes in the older adult?
-Dec in gray & white matter
-Small overall loss of neurons
-Atrophy
-Increased ventricular size
-Decreased epidural space & CSF volume
-Increased dura permeability
-More sensitive to RA and Neuraxial
-Dec Dopamine, Ach, NE, and serotonin
-Intact electrical activity, cerebral metabolic rate, and cerebral blood flow
Why are older adults more sensitive to RA and neuraxial?
-Decreased epidural space
-Decreased CSF volume
-Increased Dura Permeability
What are the 4 legally relevant criterion for decision-making capacity?
1) Understanding his/her treatment options
2) Appreciating and acknowledging his/her medical condition and likely outcomes
3) Exhibiting reasoning and engaging in a rational discussion of his/her surgical treatment options
4) Clearly choosing a preferred treatment option
Frail older adults are more likely to have what?
-Increased risk for adverse outcomes
-Decreased resistance to stressors
-Complications postoperative
-Longer hospital LOS
-Discharged to a skilled or assisted living facility
A biologic state associated with increased vulnerability to adverse outcomes that result from decreased resistance to stressors as a result of deterioration in multiple physiologic systems.
Frailty
Frailty rates have been reported to be ___ to ___% in surgical patients.
4.1 - 50.3%
What is primary frailty?
Frailty that occurs as part of the intrinsic process of aging.
What is secondary frailty?
Related to the end-stage of chronic illnesses and is caused by inflammation and wasting, for example heart failure, COPD, inflammation, and wasting associated with cancer.
What are Fried’s physiologic parameters of frailty?
-grip strength
-weight loss
-walking speed
-energy level and physical activity
How do you measure a severe nutritional risk in the geriatric surgical patient?
1) BMI < 18.5 kg/m2
2) Serum Albumin <3g/dL (without evidence of renal or hepatic dysfunction)
3) Unintentional weight loss >10-15% within past 6 months
Malnutrition and protein deficiency are associated with what complications?
-Increased risk of postop complications (SSI, PNA)
-Increased hospital LOS
-Increased Mortality
How do you assess functional status?
-Ability to perform self-care tasks or ADLS
-Ability to perform instrumental activities of daily living (preparing meals, finances, driving, etc)
-Deficits in vision/hearing
The current level of function is a predictor for _____ outcomes.
Long-term
Impaired preop functional status predicts:
-Longer postop recovery time
-Poor postop outcome
-Inc risk for post-op dementia
-Inc hospital LOS
___ metabolic equivalents (METS) cardiac reserve is needed to tolerate most surgeries.
4
The most important surgical outcome in the perioperative care of older adults is?
Avoidance of functional decline and maintenance of independence (return to baseline) !!!
