Exam 4: Endocrine part II (Ash/Mar) Flashcards
Hypothroidism affects ____ to ____% of adults and is also known as
0.5%-0.8%
myxedema
Slide 31
95% of cases of hypothyroidism are ____ hypothyroidism.
What labs are expected
Primary
Low T3 and T4 despite adequate TSH
Slide 31
What is the most common cause of hypothyroidism?
2nd most common cause?
1) ablation of the gland by radioactive iodine or surgery
2) idiopathic and probably autoimmune with antibodies blocking TSH receptors
Slide 31
____ ____ is an autoimmune disorder characterized by ____ enlargement and hypothyroidism that usually affects ____
hashimoti thyroiditis
goitrous
middle-aged women
Slide 31
What does the progression of hypothyroidism look like in adults?
S/Sx?
What are other common co-existing problems?
slow, progressive course in adults
Sx: cold intolerance, weight gain, nonpitting edema
Other: SIADH is common along with fluid overload, pleural effusions and dyspnea. GI function is slow and adynamic ileus may occur
Slide 31
Hypothyroidism S/S chart
HEENT
Neuro
GI
Psych
Skin
Cardiac
Slide 32
____ women > ____y/o have subclinical hypothyroid, which is associated with increased risk of what?
20%, 60y/o
CAD if TSH is >10millunits/L
Slide 33
What is controversial in subclinical hypothyroid disease?
Throid replacement
Slide 33
How is secondary hypothyroidism characterized?
How do we differentiate b/w types of hypothyroidism
disease by reduced levels of T3, T4, and TSH
A TRH stimulation test can confirm if the pituitary is the cause by measuring pituitary responsiveness to IV TRH
In primary hypothyroidism, TRH further elevated TSH
W/ pituitary dysfunction, there is no response to TRH
Slide 33
what is the name for abnormal thyroid function tests in critically ill pts?
What do labs look like in this population?
why does this happen?
Euthyroid sick syndrome
Low T3 and T4 w/ normal TSH level
likely a response to stress, and it can be induced by surgery
Slide 33
What is the treatment for hypothyroidism?
Pre-op implications?
Tx: L-thyroxine is DOC
Pre-op:
Assess for airway compromise d/t swelling, edematous vocal cords, goitrous enlargement
Expect slower gastric emptying, aspiration rx
Cardiovascular system may be hypodynamic
Respiratory function may be compromised
More prone to hypothermia
Electrolyte imbalances possible
If elective case, Thyroid tx should be initiated at least 10 days prior
If emergent surgery: IV Thyroid replacement along with steroids ASAP
Slide 34
What is myxedema coma?
This occurs most commonly in what population?
Rare, sever form of hypothyroidism characterized by delirium, hypoventilation, hypothermia, bradycardia, HoTN, and severe dilutional hyponatremia
elderly women w/ a long hx of hypothyroidism
Slide 35
What triggers myxedema coma?
What is a cardinal feature of myxedema coma?
triggers: infection, cold, and CNS depressants
cardinal feature: hypothermia d/t impaired thermoregulation
Slide 35
Myxedema coma is a ____ ____ with a mortality rate > ____%
Tx?
how long does is take which vital signs to improve?
medical emergency
50%
Tx: IV L-thyroxine or L-triiodothyronine
IV hydration w/glucose-saline solutions, temp regulation, correction of e-lyte imbalances, and stabilization of cardiac & pulmonary systems are necessary
Mechanical ventilation is frequently required
HR, BP & temp usually improve within 24 h
Slide 35
What are goiter and thyroid tumors?
What causes goiter and thyroid tumors?
Swelling of the thyroid gland d/t hypertrophy and hyperplasia of follicular epithelium
Causes: lack of iodine, ingestion of goitrogen (cassava, phenylbutazone, lithium), or a defect in the hormonal biosynthetic pathway
Slide 36
In most cases, goiter is associated with what?
A compensated euthyroid state
Slide 36
How are goiter and thyroid tumors treated?
most cases are treated with L-thyroxine
surgery indicated only if medical therapy is ineffective, and goiter is compromised airway or cosmetically unacceptable
Slide 36
Pre-op implications of goiter or thyroid tumors?
What testing should be done prior?
pre-op hx of dyspnea in upright or supine position is predictive of possible airway obstruction during GA.
CT scan must be examined to assess the extent of the tumor
PFT- flow volume loop
Echocardiogram in the upright and supine positions can indicated degree of cardiac compression
Slide 37
what do Flow volume loops look like in goiter and thyroid tumors?
Flow-volume loops in the upright and supine positions will demonstrate the site and degree of obstruction
Limitations in the inspiratory limb of the loop indicate extra-thoracic obstruction
Delayed flow in the expiratory limb indicates an intra-thoracic obstruction
Slide 37
Morbidity related to thyroid surgery approaches ____%
____ injury may be unilateral or bilateral and temporary or permanent
13%
Recurrent Laryngeal Nerve (RLN)
Slide 38
If thyroid surgery causes a unilateral RLN injury, the patient experiences what?
hoarseness but no airway obstruction, and function usually returns in 3-6months
Slide 38
During thyroid surgery, what may lead to permanent hoarseness?
ligation or transection of the RLN
Slide 38
Bilateral complications of thyroid surgery may lead to what?
It is more serious than unilateral and may cause airway obstruction and difficults coughing.
May warrant a tracheostomy
Slide 38
What other endocrine disorder can occur as a complication of thyroid surgery? When will symptoms begin and what will they be?
Hypoparathyroidism may result from inadvertent parathyroid damage. Sx of hypocalcemia occur in the first 24-48 hours postoperatively
Slide 38
____ may lead to tracheal compression. what should be kept at bedside during the immediate post-op period?
hematoma
trach-set
Slide 38
Each adrenal gland consists of what?
What is the function of these parts?
a cortex and a medulla
the cortex synthesizes glucocorticoids, mineralocorticoids (aldosterone), and androgens
Slide 39
Adrenal gland normal function and release of hormones?
Hypothalamus sends corticotropin-releasing hormone (CRH) to the anterior pituitary, which stimulates corticotropin (ACTH) release from the anterior pituitary
ACTH stimulates the adrenal cortex to produce cortisol, which facilitates the conversion of NE to EPI in the adrenal medulla
Cortisol also induces hyperglycemia, reflectinggluconeogenesis and inhibition of glucose uptake by cells
Together, cortisol & aldosterone cause sodium retention & K+ excretion
Slide 39
What is pheochromocytoma?
Catecholamine-secreting tumors that arise from chromaffin cells of the sympathoadrenal system
Slide 40
uncontrolled catecholamine release can cause what 3 things?
malignant HTN, CVA, and MI
Slide 40
associated with pheochromocytoma