Endocrine (exam 4) Flashcards
(131 cards)
1
Q
What is required for a normal glucose level?
A
A balance between glucose usage, endogenous production, and dietary intake.
2
Q
What is the primary source of glucose production in the body?
A
The liver via glycogenolysis and gluconeogenesis.
3
Q
What percentage of glucose released by the liver is metabolized by tissues?
A
75%.
4
Q
What occurs 2-4 hours after eating in terms of glucose levels?
A
Endogenous production occurs to maintain normal plasma glucose level.
5
Q
Which hormones help regulate blood glucose levels?
A
- Glucagon
- Epinephrine
- Growth hormone
- Cortisol
6
Q
What is diabetes mellitus?
A
The most common endocrine disease affecting 1 in 10 adults, resulting from inadequate insulin supply and/or insulin resistance.
7
Q
What are the main types of diabetes mellitus?
A
- Type 1a DM
- Type 1b DM
- Type 2 DM
8
Q
What causes Type 1a diabetes mellitus?
A
Autoimmune destruction of pancreatic β cells leading to minimal or absent insulin production.
9
Q
What is a characteristic of Type 2 diabetes mellitus?
A
Defects in insulin receptors and signaling pathways.
10
Q
What percentage of all diabetes cases does Type 1 diabetes account for?
A
5-10%.
11
Q
What are the common symptoms of hyperglycemia (7)?
A
- Fatigue
- Weight loss
- Polyuria
- Polydipsia
- Blurry vision
- Hypovolemia
- Ketoacidosis
12
Q
What are the three main abnormalities seen in Type 2 diabetes?
A
- Impaired insulin secretion
- Increased hepatic glucose release (c/b reduction in insulins inhibitory effect on liver)
- Insufficient glucose uptake in peripheral tissues
13
Q
What is the preferred initial treatment for Type 2 diabetes?
A
Metformin.
14
Q
What are the side effects of sulfonylureas?
A
- Hypoglycemia
- Weight gain
- Cardiac effects
15
Q
What is the most dangerous complication of long-acting insulin (Glargine)?
A
Hypoglycemia.
16
Q
What is diabetic ketoacidosis (DKA)?
A
A complication of decompensated diabetes, more common in DM1, often triggered by infection/illness.
17
Q
What is the treatment for diabetic ketoacidosis?
A
- IV volume replacement
- Regular insulin: loading dose 0.1u/kg + infusion 0.1u/kg/hr
- Correct acidosis
- Electrolyte supplementation
18
Q
What characterizes Hyperglycemic Hyperosmolar Syndrome (HHS)?
A
Severe hyperglycemia, hyperosmolarity, and dehydration.
19
Q
What are common microvascular complications of diabetes?
A
*Nonocclusive microcirculatory disease w/impaired blood flow
* Nephropathy
* Retinopathy
* Peripheral neuropathy
*Autonomic neuropathy: dysrhythmias, ortho-HoTN, gastroparesis
20
Q
What is the most common cause of end-stage renal disease (ESRD) in diabetes?
A
Nephropathy.
21
Q
What triggers myxedema coma?
A
Infection, trauma, cold, and CNS depressants.
22
Q
What is the cardinal feature of myxedema coma?
A
Hypothermia.
23
Q
What are the symptoms of hyperthyroidism (6)?
A
- Sweating
- Heat intolerance
- Fatigue
- Insomnia
- Osteoporosis
- Weight loss
24
Q
What is the leading cause of hyperthyroidism?
A
Graves disease.
25
What is the 1st line treatment for Graves disease?
* Antithyroid drugs (methimazole or PTU). PTU = propylthiouracil
* Iodine therapy
* Surgery (subtotal thyroidectomy)
26
What is the Whipple triad used for in diagnosing insulinoma?
* Hypoglycemia with fasting
* Blood glucose <50 with symptoms
* Symptoms relief with glucose
27
What is the normal range for TSH levels?
0.4-5.0 milliunits/L.
28
What is the ratio of T4 to T3 in the thyroid hormones produced?
10:1.
29
What are the causes of goiter?
* Lack of iodine
* Ingestion of goitrogens
* Hormonal defects
30
What is the effect of thyroid hormones on metabolic processes?
They stimulate virtually all metabolic processes.
31
What is a common symptom of diabetic neuropathy?
Loss of pain and temperature perception.
32
What is the role of glucagon in glucose metabolism?
* Stimulating glycogenolysis
* Stimulating gluconeogenesis
* Inhibiting glycolysis
33
What lifestyle factors contribute to insulin resistance (2)?
* Obesity
* Sedentary lifestyle
34
What should be assessed preoperatively in diabetic patients (4)?
* Cardiovascular system
* Renal system
* Neurologic system
* Musculoskeletal system
35
What is the treatment for myxedema coma (severe hypothyroidism)?
* IV L-thyroxine (DOC) or L-triiodothyronine
* IV hydration with glucose solutions
* Temp regulation
* Electrolyte correction
36
What is the effect of thyroid-stimulating antibodies in Graves disease?
They stimulate growth, vascularity, and hypersecretion of the thyroid.
37
What is the mortality rate for a medical emergency involving cold and CNS depressants?
> 50%
38
What is the treatment for a medical emergency involving cold and CNS depressants?
IV L-thyroxine or L-triiodothyronine, IV hydration with glucose solutions, temperature regulation, electrolyte correction, and supportive care
39
What is commonly required for patients experiencing a medical emergency with cold and CNS depressants?
Mechanical ventilation
40
What causes a goiter?
Lack of iodine, ingestion of goitrogen, or a hormonal defect
41
What is the typical state associated with most cases of goiter?
Compensated euthyroid state
42
What is the first-line treatment for goiter?
L-thyroxine
43
When is surgery indicated for goiter?
If medical treatment is ineffective, and goiter compromises airway or is cosmetically unacceptable
44
What imaging study is essential to assess the extent of a thyroid tumor?
CT scan
45
True or False: Dyspnea in upright or supine position is predictive of airway obstruction during general anesthesia.
True
46
What do flow-volume loops indicate in assessing airway obstruction?
Location and degree of obstruction
47
What indicates extra-thoracic obstruction in flow-volume loops?
Limitations in the inspiratory limb
48
What indicates intra-thoracic obstruction in flow-volume loops?
Delayed flow in the expiratory limb
49
What can an echocardiogram assess in relation to thyroid surgery?
Degree of cardiac compression
50
What kind of injury may occur during thyroid surgery?
Recurrent laryngeal nerve (RLN) injury
51
What are the potential outcomes of unilateral RLN injury?
Vocal hoarseness without obstruction, usually resolves in 3-6 months
52
What is a possible complication of bilateral RLN injury?
Airway obstruction requiring tracheostomy
53
What condition may result from inadvertent parathyroid damage during thyroid surgery?
Hypoparathyroidism
54
When do symptoms of hypocalcemia typically occur postoperatively?
Within 48 hours
55
What may a hematoma during thyroid surgery lead to?
Tracheal compression
56
What should be kept at the bedside during the immediate postoperative period after thyroid surgery?
A tracheostomy set
57
What are the two main components of each adrenal gland?
Cortex and medulla
58
What hormones does the adrenal cortex synthesize (3)?
Glucocorticoids, mineralocorticoids (aldosterone), and androgens
59
What does ACTH stimulate in the adrenal cortex? Where is ACTH produced?
Production of cortisol
Anterior pituitary
60
What condition is characterized by a tumor causing excess catecholamine secretion from chromaffin cells?
Pheochromocytoma
**Norepi, epi, and rarely dopamine
61
What can excess catecholamines lead to?
Malignant hypertension, CVA, and myocardial infarction
62
Where do 80% of pheochromocytomas occur?
In the adrenal medulla
63
What is the typical NE:EPI secretion ratio in most pheochromocytomas?
85:15
64
What symptoms may occur during a pheochromocytoma attack?
Headache, pallor, sweating, palpitations, hypertension, orthostatic hypotension
65
What diagnostic test is used for pheochromocytoma?
24-hour urine collection for metanephrines and catecholamines
66
What is the preoperative treatment for pheochromocytoma?
Alpha blocker to lower blood pressure and decrease intravascular volume
67
What is the most frequently used preoperative alpha-blocker? It is used to treat pheochromocytoma
Phenoxybenzamine
**It is a noncompetitive alpha 1 antagonist with some alpha 2 properties
68
What should never be given before an alpha-blocker in pheochromocytoma patients?
Nonselective beta-blockers
**Blocking vasodilatory B2 receptors results in unopposed alpha antagonism, leading to vasoconstriction and hypertensive crisis
69
What is the hallmark symptom of primary hyperaldosteronism?
Spontaneous hypertension with hypokalemia
70
What is the treatment for primary hyperaldosteronism (6)?
Aldosterone antagonist (Spironolactone), potassium replacement, antihypertensives, diuretics, tumor removal, possible adrenalectomy
71
What is the hallmark of hypoaldosteronism?
Hyperkalemia in the absence of renal insufficiency
72
What is the treatment for adrenal insufficiency?
Steroids
73
What are the two types of adrenal insufficiency?
Primary and secondary
74
What characterizes primary adrenal insufficiency (Addison's disease)?
Autoimmune adrenal gland suppression
**>90% of the glands must be involved before signs appear
75
What is a common cause of secondary adrenal insufficiency?
Iatrogenic factors such as synthetic glucocorticoids, pituitary surgery, or radiation
76
What is the diagnostic criteria for adrenal insufficiency?
Baseline cortisol < 20 μg/dL and remains < 20 μg/dL after ACTH stimulation
77
What is the role of parathyroid hormone (PTH)?
Maintains normal plasma calcium levels by promoting calcium movement across GI tract, renal tubules, and bone
78
What is the most common cause of primary hyperparathyroidism?
Benign parathyroid adenoma (90%)
79
What are the symptoms of hyperparathyroidism?
Lethargy, weakness, nausea/vomiting, polyuria, renal stones, peptic ulcer disease, cardiac disturbances
80
What is the treatment for hyperparathyroidism?
Surgical removal of abnormal portions of the gland
81
What is the difference between primary and secondary hyperparathyroidism?
**Primary** is due to increased secretion of PTH, while **secondary** is a compensatory response to hypocalcemia caused by something else, i.e chronic renal failure
82
What is the hallmark of hypoparathyroidism?
Deficient PTH, usually iatrogenic
83
What are the typical symptoms of acute hypocalcemia?
Inspiratory stridor or laryngospasm
84
What is the common treatment for chronic hypoparathyroidism?
Calcium replacement and Vitamin D
85
What hormones does the anterior pituitary secrete (6)?
GH, ACTH, TSH, FSH, LH, prolactin
86
What condition is characterized by excessive growth hormone?
Acromegaly
87
What is the typical diagnostic lab finding in acromegaly?
Elevated insulin-like growth factor 1 (IGF-1)
88
What are anesthesia implications for patients with acromegaly?
Distorted facial anatomy may interfere with mask placement, and upper airway obstruction is a risk (i.e enlarged tongue & epiglottis)
89
What is diabetes insipidus (DI) caused by?
Vasopressin (ADH) deficiency
90
What distinguishes central/neurogenic DI from nephrogenic DI?
Response to DDAVP
**DDAVP is the treatment for **neurogenic** DI
91
What is the initial treatment for diabetes insipidus?
IV electrolytes to offset polyuria
92
What syndrome can result from intracranial tumors or lung cancer?
Syndrome of Inappropriate ADH
93
What is the treatment for severe hyponatremia?
Hypertonic saline
94
Glucagon:
Stimulates ________ and _______
Inhibits _______
Glycogenolysis; gluconeogenesis
Glycolysis
95
What is characteristic of type 1b DM?
rare, non-immune disease of absolute insulin deficiency
96
(3) causes of insulin resistance
1. abnormal insulin molecules
2. circulating insulin antagonists
3. insulin receptor defects
97
What is the MOA of sulfonylureas?
Stimulates insulin secretion from the pancreas
98
What is the MOA of Metformin (2)?
1. Enhances glucose transport into tissues
2. Decreases triglyceride and LDL levels
99
Repetitive hypoglycemia can lead to _______
Hypoglycemia unawareness ----> leads to neuroglycopenia (fatigue, confusion, HA, seizures, coma)
100
T/F: DKA is more common in DM2 than DM1
False: more common in DM1
101
T/F: hyperglycemic hyperosmolar syndrome (HHS) occurs more frequently in DM2 than DM1
True!
102
A rare, benign insulin-secreting pancreatic tumor
Insulinoma
103
A insulinoma is diagnosed based on the whipple triad, which is?
1. Hypoglycemia with fasting
2. Blood glucose <50 with symptoms
3. Symptom relief with glucose
104
What is the MOA of diazoxide? Given preop before insulinoma removal
Inhibits insulin release from B cells
**Other treatments include verpamil, phenytoin, propranolol, glucocorticoids, octreotide
105
Production of thyroid hormones depends on which element?
Iodine
106
T4 and T3 are also known as?
Monoiodotyrosine, diiodotyrosine
107
Thyroid function is regulated by _______, _______, and _______
Hypothalamus, pituitary, and thyroid glands
108
_______ _______ is the best test of thyroid action at the cellular level
TSH assay
109
Used to test pituitary function and TSH-secretion
TRH (thyrotropin releasing hormone) stimulation test
110
The (3) major causes of hyperthyroidism
1. Grave's disease
2. toxic goiter
3. toxic adenoma
111
T/F: Grave's disease is much more common in men
False: more common in women
112
_______ (medication) impairs the peripheral conversion of T4 to T3. Relieves symptoms of Grave's disease
Propranolol
113
A life-threatening hyperthyroid exacerbation. What can trigger it?
Thyroid storm
Stress, trauma, infection, medical illness, or surgery
114
The hypothalamus sends ______ - ______ hormone to the anterior pituitary, which stimulates the release of ACTH
Corticotropin-releasing hormone
115
In pheochromocytoma, NE and EPI is released in what ratio (reverse of normal secretion)?
85:15 (NE:EPI)
116
T/F: pheochromocytoma can result in coronary vasoconstriction, cardiomyopathy, CHF & EKG changes
True!
117
High plasma ACTH stimulates adrenal cortex to produce excess cortisol
ACTH-dependent Cushing's
118
Excessive cortisol production by abnormal adrenocortical tissue that is not regulated by CRH and ACTH
ACTH-independent Cushing's
**CRH and ACTH levels are actually suppressed
119
The most common cause of ACTH-independent Cushing's
Adrenocortical tumors
120
What is the treatment of choice for hypercortisolism (Cushing syndrome)?
Transsphenoidal microadenomectomy
**alternatively, subtotal resection of the anterior pituitary
121
Sudden central weight gain, moon face, ecchymoses, HTN, glucose intolerance, muscle wasting, depression, and insomnia are S&S of _______
Hypercortisolism (Cushing syndrome)
122
Excess secretion of aldosterone caused by a tumor (aldosteronoma)
**Renin activity is suppressed
Primary hyperaldosteronism
123
caused by elevated renin levels
Secondary hyperaldosteronism
124
What is the hallmark symptom of **hypoaldosteronism**?
Hyperkalemis in the absence of renal insufficiency
125
T/F: heart block, orthostatic HoTN, and hyponatremia are S&S of hypoaldosteronism
True!
126
What characterizes secondary adrenal insufficiency?
Hypothalamic-pituitary supression leading to a lack of CRH or ACTH production
**So ACTH leads to cortisol production/release
127
How is adrenal insufficiency diagnosed?
Baseline cortisol <20 micrograms/dl even after ACTH stimulation
**Relative adrenal insufficiency is indicated when the baseline cortisol level is higher but the ACTH stimulation test is positive
128
What are the typical symptoms of **chronic** hypocalcemia?
Fatigue, cramps, prolonged QT, cataracts, SQ calcifications, and neurological defects
129
What does the posterior pituitary store (2)?
1. vasopressin
2. oxytocin
*after being synthesized in the hypothalamus
130
Low-salt, low-protein diet, thiazide diuretics, and NSAIDS are the treatment for _______ ________ _______
Nephrogenic diabetes insipidus
131
Characterized by hyponatremia, decreased serum osmolarity, and increased urine sodium and osmolarity
Syndrome of inappropriate ADH (SIADH)
