Term
How does the CNS recovery time in the elderly compare to the young? What might increase the impact?
So why do we care? |
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Definition
Elderly patients often take more time, especially if they were confused or disoriented pre-op.
This could be a problem, cuz we usually send them home! |
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Term
| What are the 3 categories of post-op cognitive disorders? |
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Definition
Delirium
Mild Cognitive Disorder (commonly called POCD)
Dementia |
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Term
How common is delirium in the elderly after surgery?
What is included in dementia? |
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Definition
10-15% of elderly after GA
Extremely rare, includes cognitive defects in multiple domains and severe impairment in occupational and social function. |
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Term
Post-op delirium occurs in 5-50% of the elderly, presenting on POD 1-3.
MANY factors are thought to play in this. I'm not sure entirely how to phrase this as a question, so list as many of the factors you can think of, and there's probably at least 5 more. |
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Definition
Cellular proteins altered by potent inhaled agents
Central cholinergic insufficiency
Microemboli
Preexisting subclinical dementia
Hypoxia
Fever
Infection (UTI, sinusitis, pneumonia)
Electrolyte abnormalities, Anemia
Pain
Sleep deprivation
Unfamiliar environment |
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Term
| "Deterioration of intellectual function presenting as impaired memory or concentration" is the definition of what? |
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Definition
| Postoperative cognitive dysfunction |
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Term
| How severe is POCD usually? How long does it usually take to manifest? |
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Definition
Usually mild
May not be detected until days to weeks after surgery, and duration may be several weeks or permanent |
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Term
| Why is POCD difficult to diagnose? |
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Definition
| The diagnosis must be corroborated with neuropsychological testing and can only be made if there is evidence of greater memory loss than one would expect due to normal aging. This means the pt has to be tested prior to surgery and at least several weeks after surgery to determine if cognitive decline has occurred. |
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Term
| What are some contributing factors to POCD? (there are 6) |
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Definition
Drug effects
Pain
Hypothermia
Underlying dementia
Metabolic disturbances
Severity of surgery
Low levels of neurotransmitters (acetylcholine) may contribute |
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Term
| If low levels of acetylcholine may make POCD worse, what drugs specifically can impact this? Of this class of drugs, which one probably wouldn't impact? |
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Definition
| Central acting anticholinergics (scopalamine, atropine). Glycopyrolate does not cross the BBB, so it should not. |
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Term
True of false:
The incidence of POCD is less if using regional with sedation than GA |
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Definition
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Term
| Which is more likely to impact POCD: the surgery, or the anesthesia? |
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Definition
| Animal studies suggest that anesthesia alone, without surgery, can impair learning for weeks in older animals. |
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Term
| Risk factors for POCD can be grouped into 3 different categories. What are they? |
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Definition
High-risk patients (Pts already moving toward dementia... the stress of surgery can push them over their "functional cliff")
High-risk surgical procedures (cardiac or ortho)
High-risk anesthetic techniques |
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Term
| What are 3 big implications of post-op neurocognitive disorders? |
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Definition
Loss of independence
Withdrawal from society
Death |
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Term
| True or false: At hospital discharge, cognitive decline is a predictor of worse long-term cognitive outcome? |
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Definition
| True dat--those with pump head just don't do as well. |
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Term
How might the BIS affect mortality rates?
How does TIVA compare to GA? |
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Definition
Risk-adjusted mortality rates decreased when the BIS was consistently used. One study indicated a 19% increase for mortality for each hour the BIS was below 45!
GA increased the risk of death by 3X |
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Term
Regarding musculoskeletal changes in the elderly, answer true or false to the following:
1. Increased muscle mass
2. Neuromuscular junction thickens
3. Nicotinic receptors remain constant in number
4. Skin atrophies
5. Veins are frail
6. Positioning presents no more of a challenge with the elderly than anyone else
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Definition
1. False--it's reduced (which is why creatine levels remain constant)
2. True
3. False. There is an extra-junctional spread of nicotinic receptors
4. True
5. True
6. Of course this is false--the arthritic joints and buffalo humps make everything more difficult
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Term
| What happens to the muscle mass and body fat percentages in old folks, and how does this impact the distribution of water and fat soluble drugs? (yes, that's lots of questions in one sentence. Deal with it, bitches.) |
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Definition
Decreased muscle mass
Increased body fat
Decreased volume of distribution for water soluble drugs
Increased volume of distribution for fat soluble drugs |
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Term
What happens to the drug plasma concentration for water and fat soluble drugs?
What happens to the elimination half-life? |
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Definition
Increased plasma concentration for water soluble drugs, decreased for fat soluble.
Increased elimination of water soluble drugs, decreased elim. of fat soluble. |
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Term
| What happens to albumin levels, and how does this impact drug levels? Does albumin bind more to acids or bases? What binds to the other? |
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Definition
| Decreased albumin levels, leading to increased plasma concentrations. Albumin binds more to acids, whereas alpha 1 acid glycoprotein levels INCREASE, which binds basic drugs. |
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Term
Lets talk about the onset of volatiles.
1. What will happen to the onset if cardiac output is decreased?
2. What will happen if there is a V:Q abnormality?
3. What happens to the myocardial depressant effect of volatiles in old people?
4. Why is recovery delayed? |
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Definition
1. Onset will be increased
2. Onset will be delayed
3. The myocardial depressant effect is exaggerated
4. Due to increased volume of distribution in fat, decreased hepatic function, decreased pulmonary gas exchange |
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Term
Do dose requirements change for old people for induction drugs (propofol, etomidate, barbs, opioids, and benzos)?
What about succs and NDMR? |
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Definition
Usually require lower doses of induction agents--usually 50% less benzos.
Succs and NDMRs are unaltered with aging, but with a decreased cardiac output and slow muscle blood flow, they may as much as double the longevity. |
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