Exam 3 YSKs Flashcards
1
Q
Above what age is considered an ASA-2?
A
- 65
2
Q
What are the elevated age-related risks with anesthesia related to?
A
- Agre related disease have a more important role than the age alone
3
Q
What are the two types of depression?
A
- Long-term endogenous
- Short-term reactive
4
Q
What are the symptoms of short-term reactive depression?
A
- Poor appetite
- Weight-loss
- Agitation
- Recurrent thoughts of suicide
5
Q
Distinguish dementia from delirium.
A
- Permanent
- Progressive
6
Q
What are the cardiovascular physiological changes associated with aging?
A
- Reduced arterial compliance (Increased afterload and LVH)
- Diastolic BP unchanged or decreased
- CO typically declines
- Decreased HR (Increase in vagal tone, decreased adrenergic sensitivity)
- Increased dysrhythmias
- Decreased cardiac reserve (exaggerated after decreased in BP after anesthesia)
Prolonged circulatory time (prolonged drug effect time) - Diminished response to hypovolemia, hypotension, hypoxia (less increase in HR)
7
Q
What effect does aging have on VAA and why?
A
- Faster induction
- Less CO- Less uptake- Less “whisking away”- faster alveolar build-up
8
Q
During what stage of anesthesia care is ventilatory impairment most common with the elderly?
A
- PACU
- Ensure good oxygenation
9
Q
What physiological age-related changes are seen in the renal system?
A
- Renal blood flow decrease
- Kidney mass decrease (number of glomerulus is 1.2 million)
- Tubular length decrease
10
Q
What changes are seen with creatinine and BUN in the aging kidney?
A
- Creatinine does not change
- BUN gradually increases
- There is a decrease in muscle mass
11
Q
What physiological hepatic and GI changes are seen in the elderly?
A
- A decrease in esophageal and intestinal motility
- Decreased gastroesophageal sphincter tone (increased risk for pulmonary aspiration)
12
Q
What age-related changes are seen in the CNS?
A
- Cerebral blood flow decrease
- Decrease in brain mass
13
Q
Do geriatric patients require higher or lower dose of local and general anesthetic?
A
- Reduced doses of each
14
Q
What age-related changes that affect regional anesthesia in geriatrics?
A
- Reduced dose requirements
- But may need to dose more frequently
15
Q
What can changes can be expected from spinal anesthesia in geriatrics?
A
- A longer duration of action can be expected
- Varying states of an acute state of confusion postoperatively
16
Q
What are the general pharmacologic considerations in geriatrics?
A
- Decreased volume of distribution (increased total body fat, decreased total body water) for water-soluble drugs
- Elimination half-life increased (decreased hepatic and renal blood flow)
- Altered plasma protein binding
17
Q
What happens with mean alveolar concentration in geriatrics?
A
- Decreased MAC
- Approximate 4% decrease every decade after 40 years old
18
Q
What is a major cardiovascular effect of VAA in the elderly?
A
- Exaggerated myocardial depressant effects
19
Q
What are the dose requirements of nonvolatile anesthetic agents in geriatrics?
A
- Lower dose requirements
- Benzos accumulate in fat stores, VOD is larger, elimination is slowed
20
Q
What are the age-related pharmacologic changes with muscle relaxants?
A
- Decreased CO, prolonged onset
- Decreased renal clearance, delayed recovery
- ** Decreased hepatic clearance, elimination half-life and duration of action prolonged
- Decreased plasma cholinesterase, prolonged Succinylcholine effect
21
Q
What is an important GI consideration in the management of the geriatric patient?
A
- Beneficial to attempt to increase gastric pH and decrease gastric volume
22
Q
What can be expected with spinal anesthesia in the elderly?
A
- More sensitive to spinal anesthesia
- Prolonged duration of action
- Exaggerated drop in BP (ensure fluid volume)
23
Q
What is the purpose of the endocrine system?
A
- Works with the nervous system to regulate homeostasis
- Regulates:
- Behavior
- Growth
- Metabolism
- Fluid status
- Development
- Reproduction
24
Q
How are endocrine glands distinguished from exocrine?
A
- Secrete their hormone products into surrounding extracellular fluid
- Surrounding by extensive vascular network
25
What are some important endocrine glands?
- Pituitary gland
- Thyroid gland
- Parathyroid gland
- Adrenal gland
- Pancreas
- Ovaries and testes
- Placenta
26
What is endocrine function mediated by?
- Hormones
- "signaling molecules"
- Transmission of a hormonal signal through the bloodstream to a distant target cell, often over long distances
27
Describe paracrine function
- Hormone signal acting on a neighboring cell of a different type
- Cover short distances
- Alpha and Beta cells in the pancreas
28
Describe autocrine function
- Secreted hormones act on the producer cell itself or on neighboring identical cells of an identical type
29
What are the three major categories of hormones?
- Proteins or peptides (most in body)
- Amines or amino-acid derivatives
- Steroids
30
What are some major peptide or protein hormones?
- Insulin
- GH
- Vasopressin
- Angiotensin
- Prolactin
- EPO
- Calcitonin
- Somatostatin
- ACTH
- Oxytocin
- Glucagon
- PTH
- Synthesized in endocrine cells, processed by the cell and stored in secretory granules within the endocrine gland
31
What are some major sites of hormone degradation and elimination?
- Liver
- Kidneys
- A small amount of degradation occurs at the target cell itself
32
Describe hormone receptor activation:
- Hormone receptors either on the surface of cells or inside cells
- Every hormone has a specific onset and duration of action
- Hormonal effects may be generated in seconds minutes or several hours to days
33
What is the relationship between the amount of hormone receptor to circulating hormone?
- Hormone receptor number is usually inversely related to to the concentration of the circulating hormone
34
What are the three control mechanisms of hormones?
- Neural (evoke hormone secretion according to stimulation
- Biorhythms (Circadian)
- Feedback mechanisms
35
Describe positive feedback mechanisms:
- Hormone A causes more of hormone A
36
Describe negative feedback mechanisms:
- Limits or terminates hormone secretion once a response has occurred
37
Describe the pituitary gland:
- Hypophysis, known as the master gland
- Secretes hormones with far-reaching effects on homeostatic, developmental, metabolic, and reproductive functions of the body
- A small endocrine gland located on the base of the brain
38
What is anatomically significant about the pituitary gland?
- Connected to the overlying hypothalamus by the hypophyseal stalk
39
What are the six primary hormones of the anterior pituitary lobe?
- GH (promotes skeletal body growth and protein/carb metabolism)
- ACTH (Regulate growth of adrenal cortex; regulates cortisol androgenic hormones and skin pigment)
- TSH (growth and metabolism of thyroid gland, controls most systems of body)
- FSH (spermatogenesis in males, follicle development in females)
- LH (Induces ovulation, corpus luteum stimulation, stimulates testosterone production in testes)
- Prolactin (Produces mammary gland development and milk production)
40
What is a major perioperative consideration during surgery of the anterior pituitary gland?
- May require thyroid hormone replacement and corticosteroid coverage in the perioperative period
- May have DI (administer vasopressin)
41
What conditions lead to the secretion of GH?
- Stress
- Hypoglycemia
- Exercise
- Deep sleep
42
What symptoms are related to hypersecretion of GH?
- Overgrowth of internal organs
- Lung volumes increase (V/Q mismatch)
- Limited exercise tolerance
- Cardiomyopathy
- HTN
- Accelerated atherosclerosis can lead to symptomatic cardiac disease (CHF, dysrhythmias, aortic aneurysms)
43
What ECG findings may present with hypersecretion of GH?
- Often show LVH
- Conduction defects
- ST-wave depression
44
What is the aim of acromegaly treatment?
- Restoring normal GH levels
| - Micro resection of anterior pituitary tumor
45
What are the two important peptide hormones of the posterior pituitary?
- ADH
| - Oxytocin
46
Where are the hormones of the posterior pituitary synthesized?
- ADH largely synthesized in the supraoptic nucleus
- Oxytocin in the paraventricular nucleus
- Neither is synthesized in the posterior pituitary itself
47
What is the primary purpose of ADH?
- Increase urine osmolarity
- Decrease serum osmolarity
- Increase blood volume
- Urine concentration/vascular dilution
- Collecting ducts impermeable to water reabsorption without ADH
- ADH promotes hemostasis
48
What triggers the secretion of ADH?
- Increase in plasma osmolarity or plasma sodium ion concentration
- Decreased blood volume
- Decreased BP
- The osmotic threshold for ADH release is 285mOsm/L
- Decreased blood volume or blood pressure provokes ADH release
49
What occurs with deficient ADH?
- DI
- Polyuria
- Serum concentration ( >290mOsm/L)
- hypernatremia ( >145mEq/L)
50
What occurs with the hypersecretion of ADH?
- SIADH
- Plasma hypotonicity ( <270 mOsm/L)
- Dilutional hyponatremia ( <130 mEq/L)
- Water intoxication
- Brain edema
51
What percentage of calcium is bound to plasma proteins and what percentage is ionized and in blood?
- 40% protein-bound
| - 60% ionized and circulating in blood, portion that exerts effect
52
What portion of Ca++ exerts physiologic effects?
- Ionized Ca++
53
What is normal serum Ca++ concentration?
- 8.5-10.5 mg/dL
54
What is normal ionized Ca++
1.1-1.23
55
What effect does alkalosis have on Ca++ concentration
- Decreases ionized Ca++
56
What effect does acidosis have on Ca++ concentration?
- Increases ionized Ca++
| - But decrease in plasma Ca++?
57
What is the most important Ca++ regulator and what are its' triggers?
- PTH
- Decreases in plasma Ca++ stimulate PTH secretion
- Increases in plasma Ca++ inhibit PTH secretion
58
What is the endocrine role of Vitamin D?
- Augments intestinal absorption of Ca++
- Facilitates action of PTH on bone
- Augments renal absorption of calcium in distal tubules
- Lack of Vitamin D (by low UV light) effects Ca++
- 99% of Ca++ stored in bone
59
What is the relationship between PTH and Mg+ and Phosphatemia?
- Hyperphosphatemia and acute hypomagnesemia stimulate PTH secretion
- Ca++ and Phosphate have inverse relationship
60
What are the ECG findings related to hypercalcemia?
- Cardiac conduction disturbances
- Shortened Q-T interval
- Prolonged P-R
61
Describe the treatment for hypercalcemia:
- Rehydration followed by brisk diuresis
- Biphosphonate or calcitonin administration
- Administer 40-80mg of lasix, calciuresis
- Treat underlying cause
62
What are the anesthetic considerations involved with hypercalcemia?
- Serialized monitoring of Ca++, Mg+, and K+
- Avoid hypovolemia and acidosis
- Invasive monitoring may be necessary
- Unpredictable responses to anesthetic agents
63
What are the ECG findings found with hypocalcemia?
- Prolonged Q-T interval
- Delayed ventricular repolarization
- Predisposed to ventricular dysrhythmias
64
How much insulin does the pancreas normally produce daily?
- 50-60 Units
- Half gets eliminated with the first-pass effect
- 25-30 Units gets delivered peripherally
65
Describe the control of insulin secretion:
- Ingestion increases insulin secretion
Plasma insulin levels increase 30-60 minutes after meal (5-10 fold)
- Plasma glucose most important stimulator of insulin release, directly activate B-cells for insulin synthesis and secretion
- Low plasma glucose inhibits this response
- Amino acids also potent stimulators of insulin release
66
What is the most important role of glucagon?
- Enhance hepatic glucose output and increase plasma glucose
67
What are the major stimulators of glucagon release?
- Epinephrine
- Cortisol
- GH
* * Infection
* * Hypoglycemia
* * Toxemia
* * Severe injury
* * Surgery
68
What is the diagnostic fasting glucose level for diabetes?
- 126
69
What are the major distinguishing factors behind Type I DM?
- Less than 10%
- Absolute deficiency of insulin
- Dependent on exogenous insulin
70
What are the major distinguishing factors behind Type II DM?
- 90% of DM
- Impaired insulin secretion
- Peripheral insulin resistance
- Both
71
Describe the anesthetic management of the patient with DM:
- Most common endocrine disorder in surgical patients
- High morbidity and mortality in the perioperative period
- Schedule case earlier in the day
- Target BG is 120-140 pre-operatively
- Oral hypoglycemics increase the risk for intraoperative hypoglycemia
72
What is a major advantage of RA in the operative care of the diabetic patient?
- Produces less deleterious changes in glucose homeostasis
73
The universal goal for perioperative blood glucose is:
- BG= 120-140
74
What is the treatment for hypoglycemia in the surgical patient?
- 25mL of 50% glucose
| - Blood glucose of 40-60 produces mild symptoms of hypoglycemia
75
Which thyroid hormone is more abundant in the body?
- T4
| - T3 is more potent and less protein bound
76
What are the physiologic effects of thyroid hormone?
- Increase in metabolism
- A rise in O2 consumption...
- CO2 production
- HR and contractility increase
- Increase in minute ventilation
77
Describe the clinical manifestations of hyperthyroidism:
- Weight loss
- Heat intolerance
- Muscle weakness
- Diarrhea
- Hyperactive reflexes
- Nervousness
- Fine tremor
- Exophthalmos
- Goiter
- Cardiac signs, particularly w/ Grave's Disease (CHF= work-up thyroid disease) (Sinus Tach, A.fib.)
78
Describe the intraoperative anesthetic considerations with hyperthyroidism:
- Avoid drugs that stimulate the SNS (Pancuronium, Ketamine)
- Patients typically on inderal/propranolol
- Induction agent of choice is thiopental
- **Patients may be hypovolemic and vasodilated
- No change in MAC levels in patients with hyperthyroid
79
What is the most serious postoperative threat in patients with hyperthyroidism and how does it manifest?
- Thyroid storm
- Hyperpyrexia
- Tachycardia
- Altered consciousness
- Hypotension
- Tx. consists of: hydration, cooling, esmolol or propranolol,
80
How do you distinguish thyroid storm from MH?
- No muscular rigidity
| - Marked acidosis
81
What are the postoperative risks associated with hyperthyroidism?
Subtotal thyroidectomy is associated with a number of postoperative risks:
- Recurrent laryngeal nerve palsy (One nerve results in hoarseness, two nerves can result in stridor)
- Hematoma formation
- Hypoparathyroidism
- Pneumothorax
82
What are the clinical manifestations of hypothyroidism?
- Weight gain
- Cold intolerance
- Muscle fatigue
- Lethargy
- Constipation
- Hypoactive reflexes
- Dull facial expression
- Depression
- CV manifestation
- Pleural, abdominal, pericardial effusions, decreased myocardial contractility,
- Cool and mottled extremities
- Decreased CO and SV
83
Describe myxedema coma:
- Extreme hypothyroidism
- Impaired mentation
- Hypoventilation
- Hypothyroidism
- Hyponatremia
- CHF
- More common in elderly after surgery or trauma
84
Describe the anesthetic considerations with hypothyroidism:
- Pts. more susceptible to hypotensive effects of anesthetic agents, diminished CO
- Potential complications:
- Hypoglycemia
- Anemia
- Hyponatremia
- Large tongues= difficult intubation
- Hypothermia
- Blunted baroreceptor, decreased CO
* ** Delayed recovery from GETA, may be ventilated post-op for longer
85
What is produced in the adrenal cortex?
- Mineralcorticoids (Aldosterone), Glucocorticoids (Cortisol), androgens,
86
What is produced in the adrenal medulla and in what proportion?
- Dopa
- Epi (80%)
- Norepi. (20%)
87
What is the major function of aldosterone?
- Causes sodium to be reabsorbed in the distal renal tubule in exchange for K+ and H+ ions
- Net effect= reabsorption of water
88
What's an important consideration of adrenalectomy and glucocorticoid deficiency?
- Stress dose of corticosteroid
| - 100mg hydrocortisone q 8 hrs.
89
What are the clinical manifestations of catecholamine excess?
- Headaches
- HTN
- Sweating
- Palpitations
90
What are the anesthetic considerations in the care of the patient with catecholamine excess?
- Assessment should focus on the adequacy of adrenergic block and volume replacement
- Treat intraoperative HTN w/ Cardene or Phentolamine, NOT a B-Blocker
- Post-resection may need Neo or Levo drip, watch for volume overload
