Geriatrics Flashcards
1
Q
4 physiologic changes:
A
- Basal organ function unchanged
- Decreased functional reserve
- Decreased ability to compensate
- Hearing loss
2
Q
Mechanism of aging for all organ systems:
A
Aging is associated with a loss of physiologic reserve that increases the vulnerability to disease
-decreases ability to compensate for stress
3
Q
Risk of death double every what?
A
8.5 years
4
Q
When one examines periop mortality, the risk of death also double with that?
A
Rough every additional decade of age
5
Q
CV and autonomic aging makes BP inherently more unstable during anesthesia, primarily due to (3)
A
- Exaggerated responses to changes in ventricular filling
- Exaggerated responses to changes in sympathetic nervous system activity
- Impaired baroreflex control of BP owing to a decrease response to beta-receptor stimulation
6
Q
Concomitant vascular disease may lead to what?
A
Organ hypoperfusion at BP that would be easily tolerate by a young, healthy adult
7
Q
Baroreflex begins with high and low pressure baroreceptors that send info to where?
A
Medulla via vagus and glossopharyngeal nerves
8
Q
The most prominent defect of the baroreflex in elderly subjects is the failure to mount as vigorous of what?
A
Cardiac response
9
Q
Why is there a failure in cardiac response?
A
Decrease in beta-receptor responsiveness
10
Q
The change in sympathetic nervous system activity that accompanies a change in BP is actually enhanced or declined with age?
A
Enhanced
11
Q
Alpha receptor, vasoactive component of the baroreflex is effective or not effective?
A
Just as effective as in young adults, if not more so
12
Q
Most prominent and consequential changes for CV are: (3)
A
- Decrease in response to beta-receptor stimulation
- Stiffening of the connective tissue in arteries, veins, and heart
- Increase in activity of the sympathetic nervous system
13
Q
Less important changes of CV include: (2)
A
- Gradual myocyte death without replacement
2. Diminished response to atropine
14
Q
Systolic HTN include: (3)
A
- Loss of elasticity in the arterial tree
- Ventricles that contract with good strength by more slowly than young hearts
- Poor tolerance of hypovolemia
15
Q
What are the 3 diminished chronotropic and inotropic response to anything that involves beta-receptor stimulation?
A
- Exercise
- Exogenous catecholamine administration
- Baroreflex
16
Q
L ventricular hypertrophy is due to?
A
Increased impedance to ejection of SV
17
Q
Coronary artery disease with people > than what age have a what % chance of developing significant CAD?
A
70 years
50%
18
Q
Decreased max HR attainable due to what 2 things?
A
- “Beta-blockade” that occurs with aging
2. Fibrosis/atrophy of the conducting system that occurs
19
Q
Cardiac reserve is maintained by what?
A
Frank starling mechanism
20
Q
CO increased by an enhance SV resulting from an increase of what?
A
End diastolic volume
21
Q
Induction times of IV agents and inhaled agents?
A
IV agents: delayed
Inhaled agents: shorter onset
22
Q
Frank starling mechanism is a dependence on a catecholamine mediated increase in what 2 things?
A
HR and inotrophy
23
Q
Sarcomere stretch enhances the sensitivity of the contractile proteins to calcium, thereby increasing the strength of contraction
A
Frank starling mechanism
24
Q
Ventricle response less effectively to what?
A
Beta receptor stimulation
25
Since ventricles response less effectively to beta receptor stimulation, then the ventricle must depend almost solely on what?
Frank starling mechanism
26
90% of 80 year old patients have what heart issue?
Regurgitation
27
Pacemaker cell reduced by 90% at what age?
70
28
What specific dysrhythmias increases with age?
Afib
29
Ability for old heart to withstand stress is significantly increased or decreased?
Decreased
30
Max body oxygen consumption is the product fo what 3 things?
1. CO
2. Oxygen carrying capacity of the blood
3. Ability of the body to extract oxygen from the blood
31
With age, max oxygen consumption decreases at approximately how much per decade? And decline steepens after what age?
10%; 60
32
Decrease in max CO is the primary contributor to the decline owing to the decrease in what?
Max HR
33
Rule of thumb for max HR?
220 - age
34
There is a moderate decrease in resting what with age?
SV
35
Do hemoglobin levels decrease with age?
No
36
Ventricles must overcome what in order to eject blood?
Aortic pressure
37
The strength of a given contraction is largely determine when during a contraction?
Beginning
38
If most of the effort of the contraction is used up just to overcome aortic pressure, what does the SV look like?
Very little
39
The ventricle must increase its contractile effort and will do so by what 2 things?
1. Increasing contractility
2. Increasing end-diastolic volume to increase the sarcomere stretch (Frank-Starling curve or length-tension relationship)
OR BOTH
40
The inability to increase contractility as easily as in a young heart makes the elderly heart more dependent on what?
Ventricular filling
41
One can expect the elderly heart to be less tolerant to what?
Hypovolemia
42
Elderly patients have decline in what 2 things at peak exercise?
SV and HR
43
Inability of these individuals to augment stroke volume is caused by: (4)
1. Decrease in the ability of the heart to increase diastolic filling
2. Decrease in systolic pump function caused by an increased afterload
3. Intrinsic myocardial contractile defects
4. Greater diminution of the cardiovascular response to beta-adrenergic stimuli
44
During exercise, mixed venous oxygen levels increase or decrease and why?
decrease dramatically, mostly because exercising muscle is capable of extracting as much as 90% of the delivered oxygen
45
Training improves maximal body oxygen consumption to the same or less degree in young and old and what does it improve?
Same; increase in LVED volume
46
Elderly women improve their oxygen consumption primarily by what?
increasing oxygen extraction
47
Two mechanisms cause this increase in systolic blood pressure (systolic HTN):
1. Stiffening of the arteries typically leading to systolic hypertension
2. The speed of transmission of the pressure wave
48
Approximately half of the stroke volume still remains where?
thoracic aorta at the end of ejection
49
a stiffened thoracic aorta will develop a higher or lower pressure with the increase in volume in comparison to a softer, more balloon-like aorta?
Higher
50
In the elderly, the pressure wave travels faster or slower through a stiff artery than a pliable artery
Faster
51
The wave pressure wave returns to the heart when?
Latter part of the ejection rather than diastole
52
The increased pressure in late ejection places a strain where?
LV
53
strength of the contraction does what during ejection progresses?
Decreases
54
In the elderly, the returning wave increases pressure when and what does that cause the heart to do?
Late in ejection so the heart must work harder to eject
55
Heart strain stimulates what?
Muscle growth
56
The systolic hypertension, particularly the late systolic hypertension, causes what?
Ventricular hypertrophy
57
The veins contain at least what % of the body's blood?
75%
58
responsible for maintaining a relatively constant central blood volume (lungs and heart) despite changes in posture or changes in blood volume
Veins
59
If there is inadequate blood volume in the veins, venous pressure does what?
drops significantly in stiff veins and there is inadequate venous pressure to support atrial filling
60
elderly heart become more dependent on what?
Atrial filling
61
Is the CV system Abel to maintain atrial filling?
Less able to
62
plasma epi/norepi levels?
2-4 times higher
63
Increased plasma epi/norepi levels reflects a what?
Decrease in autonomic end-organ responsiveness
- loss of receptor sites and/or a reduced receptor sensitivity.
- “Endogenous beta-blockade of aging“**
64
chrono/inotropic response
Reduced
65
Baroreceptor responsiveness?
reduced
| -less tachycardia in response to hypotension or acute hemodilution.
66
Anesthetics increase or decrease sympathetic tone
Decrease
67
Response to Atropine?
Decrease
68
Does age compromise the response to acetylcholine at the muscarinic receptors?
No
69
Why is there a decrease in response to atropine?
Appears that vagal outflow decreases with age, providing less vagal stimulation to be removed by the atropine
-supported by the decrease in heart rate variability with respiration in the elderly
70
Changes in vagal activity are solely responsible for the effects of?
Respiration on HR
71
Lung volumes reduce (3)
VC
TLC
Max breathing capacity
72
Lung volumes increase (2)
FRC
| RV
73
Parenchymal changes of the lung mimic?
Emphysema
74
Loss of functional alveoli with age reduces?
Elastic recoil
75
Closing volume increases (2)
1. small airway collapse at greater lung volumes
| 2. air trapping and V/Q mismatch.
76
PaO2 incline or decline with age?
Decline
77
PaO2 equation?
102 - (.5 x age)
78
Decreased ventilatory response to (2)?
Hypoxia and hypercarbia
79
Brain mass incline or decline with age?
Decline
80
Gray or white matter is greater?
Gray
81
Brain mass decline causes what compensatory response? (2)
1. increase in CSF volume, (a form of low-pressure hydrocephalus)
2. reduction in cerebral blood flow
82
Brain atrophy causes how many loss of neurons per day?
50,000
83
What remains intact with central nervous system? (2)
CBF and CMRO2
84
Autoregulation of CBF (the response of cerebral vasculature to changes in BP) and the cerebral vasoconstrictive response to hyperventilation change?
No, stay intact
85
Body composition:
| Skeletal muscle, body fat, intracellular hydration, plasma volume, protein binding?
```
Loss of skeletal muscle (lean body mass)
Increase in % of body fat
Intracellular dehydration
Reduced plasma volume
Reduced protein binding
```
86
Increase in % of body fat specifics (3)
1. greater reservoir for lipid-soluble drugs
2. slower elimination time
3. prolonged anesthetic effects
87
Since there is a decrease in albumin, more or less available to cross BBB and produce effect due to reduced binding effectiveness of available proteins?
MORE
88
Aging has little effect on circulating what? (3)
RCM, WBC count, number/function of platelets
89
Renal tissue atrophy due to?
Loss of glomeruli (50% by age 80) and replaced with fibrosis and fatty tissue
90
GFR and RBF?
GFR: decrease 1ml/min/yr or 1-1.5%/year
RBF: decrease 1%/year after age 30 (cortex>medulla)
91
Creatinine clearance and serum Cr levels?
Creatinine clearance: decline
| Serum Cr: remain normal
92
Absorption for glucose?
Decreases
93
Urine output during and after major surgery?
Decrease
94
What does alpha agonists do to BF to kidneys and urine output?
Decrease
95
What does vasopressin do to BF to kidneys and urine output?
Increase
96
What is responsible for a very high percentage of periop mortality in elderly surgical pts?
ARF
97
It’s important to maintain UO of what?
>.5
98
Hepatic size and BF?
Size decreases and proportionally decreases with BF (40-50% by age 80)
99
Enzyme concentration and function of liver?
Maintained
100
Hepatic clearance of drugs and duration of effect?
Decreased clearance and longer duration
101
DMR decreases at what rate?
1% per ear after 30
102
What is more common intraop?
Hypothermia
103
Post op shiver?
Increase; O2 consumption up to 400-500% and may precipitate hypoxemia or myocardial ischemia
104
What can hypothermia do with anesthetic elimination and awakening?
Reduce elimination and prolong awakening
105
Airway reflexes are less effective and can cause what more likely?
Aspiration
106
Glucose and insulin effects?
Glucose: intolerance
Insulin: resistance
107
Is there a difference with NDMR dosing?
No
108
What can you see with NDMR dosing?
Longer duration and slower onset
109
Arthritic changes with airway (4)
1. Decrease cervical spine and neck mobility
2. Smaller mouth opening
3. Smaller glottic opening (smaller ETT)
4. Fragile teeth
110
Are they prone to airway collapse?
Yes
111
Blood oxygen levels?
Lower
112
After leaving PACU, hypoxia more likely and what is the equation?
PaO2=102 - (0.5 x age)
113
Less or greater need for supplemental oxygen?
Greater
114
Poor tethering of airways permits what?
Atelectasis; increasing risk of hypoxia and pneumonia
115
Chest wall does what with age?
Stiffens; more effort to expand chest, increase work of breathing
116
Increased V/Q mismatch of aging is usually overcome by what?
Supplemental oxygen
117
Risk of what is higher?
Hypoxia
118
MAC decreases what with age?
4% for each decade over age 40
119
Lipid soluble anesthetic drugs (barbiturates, benzos, opioids, etomidate) has what 4 effects?
1. Increase plasmas concentration
2. Induction dose less
3. Longer duration of effect
4. Delayed onset of action
120
Diazepam’s beta elimination half life in hours is equal to what?
Pts age in years
121
Midazolam’s half life is what?
Prolonged
122
What causes increase sensitivity to LA?
Decreased neuronal population, neural conduction velocity, interschwann cell distance
123
CO effect with SAB/epidural?
Decrease, but only by 10%
124
What is the decrease in SV way less than the decrease in EDV with SAB/epidural?
Because EF increased
125
The decrease in BP from SAB/epidural is most likely because?
Hypovolemia
126
With respect to BP lability, what may confer some degree of stability by eliminating the surgical stimulation as a source of variation in sympathetic tone?
Spinal or epidural over GA
127
Healthy elderly demonstrated how much decrease in vascular resistance during approximate T6 spinal anesthesia?
23%
128
4 facts about midazolam
1. Increased potency
2. Reduced clearance
3. Half life twice as long (1.8-6.4; about 3 hrs)
4. Decrease dose up to 75%
129
6 facts about propofol? (Clearance, Vd, blood concentration, sensitivity, hemodynamic, dosage)
1. Clearance decreased
2. Volume of distribution unchanged
3. Blood concentration increase and decrease more rapidly
4. Increased sensitivity
5. More dramatic effect on hemodynamic
6. Only fraction of usual dose
130
>55 yrs dosage of propofol:
Reduce by 20-30%
Sedation: .3-.6mg/kg
Continuous: .9-2.7mg/kg
131
Blood concentration of propofol is associated with what SBP?
50% drop
132
3 facts about ketamine?
1. Decrease in clearance
2. Duration of action extended
3. Variable psychotic side effects
133
Epidural ketamine or epidural morphine?
Less sedation and smaller risk of PONV, but need more analgesia
134
Increased mortality percentage with ASA 2, 3, 4?
2: <10%
3: 10-15%
4: >20%
135
What before surgery may help prevent preop dehydration in outpatients?
Clear liquids 2 hrs prior
136
Why is it more difficult to keep up with fluid overload?
Kidneys eliminate both excess salt and water less rapidly
137
What is used more frequently and are almost risk free if used short term?
A lines
138
What provide less accurate information about volume status than either systolic pressure variation or trans esophageal echocardiography?
CVP
139
Unless volume deficits is truly profound, the most likely cause of hypotension is probably why?
Decrease in SVR brought by decreased sympathetic outflow
140
If problem is low SVR, then what should be given?
Alpha agonists (phenylephrine)
141
Repetitive bonuses of what may become tiresome and ineffective to treat hypotension?
Ephedrine
142
State of vulnerability to internal and external stressors that increases the risk for negative outcomes…due to decline and deterioration of cellular, tissue, and organ properties
Frailty
143
Frailty is an indicator of what 2 things?
1. Biological aging
| 2. Predictor of poor outcomes in aging
144
What age do pts get the FRAIL questionnaire and the scores are associated with what?
>65 years
| 2 years
145
What does FRAIL stand for?
F: fatigue
R: resistance; unable to walk 1 flight of stairs
A: ambulation; unable to walk 1 block
I: illnesses; more than 5 illnesses
L: loss of wt; lost more then 5% in 6mths
146
What is the underlying mechanism to postop cognitive decline?
Inflammation
147
How to decrease inflammation? (2)
Steroids
| NSAID (ofirmev)
148
Ofirmev: dose every 4 hrs, 6hrs, max single, max daily
4 hrs: 650mg
6hrs: 1000mg
Single: 1000mg
Daily: 4000mg
149
Ofirmev should be administered only as a how long infusion?
15min
