Geriatrics (Exam II) Flashcards
Memory decline is related to inability to complete _____.
ADL’s
Changes in the nervous system associated with aging include what three things?
- Cerebral Atrophy
- ↓ Gray matter
- ↓ White matter
Brain ventricle size will ______ with age.
increase
Which of the following neurotransmitters show a decrease associated with aging?
Dopamine
ACh
NE
Serotonin
Glutamate
Dopamine
ACh
NE
Serotonin
Glutamate is unchanged.
Coupling of CMRO₂, CBF, and EEG is increased or decreased due to aging?
Trick question. CMRO₂, CBF, and EEG remain unchanged secondary to aging.
Is epidural space increased or decreased due to aging?
Decreased
What occurs with dura permeability secondary to aging?
Dura permeability increases.
What occurs with CSF volume secondary to aging?
Volume of CSF decreases.
What two changes are seen in myelinated fibers of dorsal and ventral nerve roots secondary to aging?
↓ diameter of roots
↓ number of roots
Elderly patients are more/less sensitive to neuraxial and peripheral nerve blocks?
more sensitive
Decreases in what two characteristics of the peripheral nervous system are noted secondary to aging?
- Inter-Schwann cell distance
- Conduction velocity
What cardiac changes are noted due to aging?
- ↓ myocyte number
- ↓ SA node cells
- ↓ conduction velocity
- ↓ contractility
- ↓ β-adrenergic sensitivity
- Thickened LV & aortic valve
What happens to vasculature as we age? Why?
Vessels become more stiff
- ↓ collagen & elastin
- ↓ Nitric Oxide vasodilation
What two factors are decreased in the lungs as we age?
- ↓ Elastic recoil
- ↓ Surfactant
What anatomic structures of the lungs become enlarged as we age? What is the result?
Bronchioles and alveolar ducts become enlarged leading to early collapse of small airways.
↑ VD
↑ closing capacity
impaired gas exchange
Loss of vertebral height and calcification of vertebrae lead to what three respiratory system consequences?
- Barrel chest
- Diaphragmatic flattening
- Chest wall stiffening
Will the following see an increase or a decrease due to aging-related lung changes?
- Vital Capacity
- Closing Capacity
- Residual Volume
- ↓ VC
- ↑ CC
- ↑ RV
FEV₁ will decrease by ___% per decade.
6-8%
What are the results of weaker pharyngeal muscles from aging-related changes?
- ↓ secretion clearance
- ↓ esophageal motility
- ↓ protective upper airway reflexes
- Inefficient coughing
Whats the most important mechanism of action for aging-related A-a gradient changes?
FRC & CC mismatch increasing
Increasing shunt w/ decreasing arterial oxygenation.
What renal consequences are there to aging?
- ↓ GFR
- ↑ Urinary retention
- ↑ UTI’s
- Blunted response to aldosterone, vasopressin & renin
Which phase of liver metabolism is more affected by aging?
Phase I more impaired
What are the components of Phase I liver metabolism?
- Oxidation-Reduction
- CYP450 Hydrolysis
What is the mechanism for increased PONV in the elderly?
Trick question. Less PONV in the elderly.
Avoid Prochlorperazine, promethazine, & metoclopramide.
With aging, muscle mass will ______ while subcutaneous fat will _______.
decrease; also decrease
What are some significant predictors of 6month & 1 year mortality for the elderly?
- Impaired cognition
- Recent fall
- ↓ Albumin
- Anemia
- Functional dependence
- Comorbidities
What four factors are thought to be involved in the pathogenesis of dementia?
- Amyloid plaques
- Tau
- Ca⁺⁺
- Neuroinflammation
Where do amyloid plaques accumulate intracellularly?
Trick question. Amyloid accumulates extracellulary.
What are amyloid plaques thought to do in the CNS?
Disrupt cell membranes
Function actually unknown, synaptic origin.
What results were seen (regarding amyloid β) with mice who were administered volatile anesthetic?
- Young mice had improved memory/learning
- Old mice had accelerated dementia
More study necessary.
What medication class can cause a significant increase in amyloid plaques?
Volatiles Anesthetics
What is a neurofibrillary tangle?
Phosphorylated and aggregated τ (tau) proteins
What is destabilized by neurofibrillary tangles?
Microtubules
Decreases in temperature by ___ °C will increase the amount of τ protein.
2-3 °C
Repeated exposure to what drug class will cause an increase in phosphorylated τ protein?
VAA’s (specifically halothane, isoflurane, & sevo)
Flip card to see graph of Amyloid and Tau relations to symptoms.
Release of what ion is exaggerated due to anesthesia? What receptors are involved?
Release of Ca⁺⁺ from ryanodine and IP₃ receptors of endoplasmic reticulum.
Exaggerated Ca⁺⁺ release in the brain is thought to be linked to ______________.
neurotoxicity
Does dantrolene cross the blood brain barrier?
No
Neuroinflammation contributes to cognitive decline through the release of which three inflammatory factors?
- Cytokines
- IL-6
- TNFα
What anesthetic drugs (mentioned in lecture) could be used to counteract inflammation?
Sus, because I checked and only one of these crosses the BBB.
Dexamethasone
Ketorolac
Lidocaine (actually can cross BBB)
General anesthesia (especially in older populations) is thought to contribute to ______.
POCD (Post-op cognitive dysfunction)
What studies support the theory of anesthesia related to post-operative cognitive dysfunction?
Anesthesia is ______ for POCD, whilst surgery is likely ________.
Causative; additive
What occurs to drugs due to decreased cardiac output secondary to aging?
- Slower distribution to site of action
- Slower redistribution
- Slower distribution to metabolic organs
What neuromuscular junction changes contribute to drug challenges in an aging patient?
- ↑ distance between axon and motor end plate
- ↓ concentration of ACh receptors
- ↓ ACh in presynaptic vesicle
- ↓ ACh release
What drug changes are seen in an aging patient regarding kidney/liver dependent metabolism?
- Prolonged drug effect
- Decreased drug need during maintenance
- Delayed recovery phase for non-depolarizing NMB’s
What is the algorithm for preoperative assessment of Thoracic surgery patients?
How is predicted post-operative FEV₁ (ppo FEV₁) calculated?
(Preop FEV₁ %) x (1 - % of lung tissue removed/100)
How many lung segments are there?
42 total
How many lung segments are in the LUL?
10
How many lung segments are in the RLL?
12
How many lung segments are in the RUL?
6
How many lung segments are in the RML?
4
The right middle lobe and right lower lobe are resected in a critically ill patient. How much lung tissue was removed in this surgery?
16/42 = 38%
Predict the post-operative FEV₁ for a patient who had their right lower lobe removed. The patients preoperative FEV₁ is 70%.
(Preop FEV₁ %) x (1 - % of lung tissue removed/100)
PPO FEV₁ =70 x ( 1 - 28/100) = 50
What is the “triad” of preoperative thoracotomy assessment?
How would the CRNA manage extubation on a post-thoracotomy patient if the PPO FEV₁ is >40% ?
If > 40%, extubate in OR if awake, warm, & comfortable (AWaC)
How would the CRNA manage extubation on a post-thoracotomy patient if the PPO FEV₁ is 30 - 40% ?
Consider extubation based on:
- Exercise tolerance
- DLCO
- V/Q
- Comorbidities
How would the CRNA manage extubation on a post-thoracotomy patient if the PPO FEV₁ is <30% ?
- Staged weaning from ventilator
- Consider extubation if >20% plus thoracic epidural anesthesia in place.
