Endocrine Flashcards
What are the 7 hypothalamic hormones?
Luteinizing hormone
Corticotropin hormone
Thyrotropin
Prolactin releasing
Prolactin inhibiting
Growth hormone inhibiting
Growth hormone stimulating
Where is the pituitary gland located?
Sella turcica
Anterior - adenohypophysis
Posterior - neurohypophysis
Which hormones are released from the anterior pituitary?
FLAT PiG
Follicle
Luteinizing
Adrenocorticotropic
Thyroid stimulating
Prolactin
Growth
What does the follicle stimulating hormone do?
Germ cell maturation and follicle growth in females
What does the luteinizing hormone do?
Testosterone production in males and ovulation in females
What does the adrenocorticotropic hormone do?
Adrenal hormone release
What does the thyroid stimulating hormone do?
Thyroid hormone release
What does prolactin do?
Lactation
What does growth hormone do?
Cell growth
What two hormones are from the posterior pituitary ? What are their functions?
Antidiuretic - water retention
Oxytocin - uterine contraction and breast feeding
Anesthetic complications for acromegaly?
Everything is large + glucose intolerance
Large face, teeth, epiglottis, narrowing of cords, turbinate’s
Increased risk of CAD, HTN, rhythm disturbances
Muscle weakness
Differentiate T3 to T4, source?
T4 - Released from thyroid
T3 - extrathyroid conversion of T4 to T3
Differentiate T3 to T4, highest concentrations?
T4 - in the blood (T4 delivers T3)
T3 - In the target cell
Differentiate T3 to T4, protein binding?
T4 - more
T3 - less
Differentiate T3 to T4, potency?
T4 - Less
T3 - more
Differentiate T3 to T4, half life?
T4 - 7 days
T3 - 1 day
How does iodine deficiency affect T3 and T4?
Iodine is a substrate that the thyroid needs to make T3 an T4
without it, NO T3 or T4
How does the thyroid affect cardiac function?
Increases
Chronotropy
Inotropy
Lusitropy
Number of beta receptors
Decreases
SVR
Number of muscarinic receptors
How does the thyroid affect respiratory function?
Increases CO2, O2 and Minute ventilation
How does the thyroid affect MAC?
Has NO effect
BUT
hyperthyroidism can have a slower induction time
hypothyroidism can have a faster induction time
Most common cause of hyperthyroidism?
Graves
also
MG
Carcinoma
Pregnancy
Most common cause of hypothyroidism?
Hashimoto’s thyroiditis
Also
iodine deficiency
Neck radiation
Thyroidectomy
Amiodaron can effect both
How are T3 and T4 affected by hyper/hypothyroidism?
Hyper - Low TSH and High T3+T4
Hypo - High TSH and Low T3+T4
Myxedema coma vs cretinism?
Myxedema coma - end stage hypothyroidism that leads to coma
Cretinism - neonatal hypothyroidism -
What three thioamides can treat hyperthyroidism ?
PTU, Methimazole, Carbimazole
Block iodine
Need 6-7 weeks to work and are only PO
Why are beta blockers used in hyperthyroidism?
Reduce SNS stimulation and inhibit peripheral conversion of T4 to T3
Contraindications to radioactive iodine?
Pregnancy
Breast feeding
When can surgery be done in patients with hyper/hypothyroidism?
Hyper - Do not proceed with elective, for emergency - give beta blockers, potassium iodine, glucocorticoid, PTU
Hypo - okay if mild or moderate disease
Best way to secure an airway with a goiter?
Awake intubation
or a technique that maintains spontaneous ventilation
Which drugs should be avoided in hyperthyroidism?
Sympathomimetics
Anticholinergics
Ketamine
Pancuronium
What is a thyroid storm?
Stressful in hyperthyroid and euthyroid and occurs 6-18 hours after surgery
S/sx
Fever > 38.5
Tachycardia
HTN
CHF
Shock
Agitation
Can mimic MH
How manage a thyroid storm?
Block synthesis (methimazole, carbimazole, PTU, potassium iodide)
Block release ( radioactive iodine, potassium iodide)
Block T4 to T3 (PTU, propranolol, glucocorticoids)
Block beta receptors (Propranolol, esmolol)
Support
How can you assess the RLN?
Have the patient say E or Moon
Can also look under DL, and use a NIM tube
What happens if the parathyroid is resected?
Hypocalcemia at least 6-12 hours after surgery
S/sx of hypocalcemia
Muscle Spasm
DELAYED GASTRIC EMPYTING (increased risk for aspiration)
Laryngospasm
Hypotension
Prolonged QT
Paresthesia
Chvostek’s sign
Trousseau’s sign
3 layers of the adrenal cortex?
GFR
G- Mineralocorticoids (aldosterone) salt
F- Glucocorticoids (cortisol) sweet
R- Androgens (dehydroepiandrosterone) sex
What is released from the adrenal medulla?
Catecholamines
Epi - 80%
Norepi - 20%
Where is angiotensinogen made?
liver
Where is ang 1 made?
systemic
Where is ang 2 made?
lung
How much cortisol is produced in a day?
15-30mg/day with a normal level of 12 mcg
Stress can create 100mg/day
How does cortisol affect cardiovascular function?
Improves it by increasing the number of beta receptors
Also helps vasculature respond to vasoconstriction
Which steroids have no glucocorticoid effects?
Aldosterone
Which steroids have no mineralocorticoid effects?
Dexamethasone
Betamethasone
Triamcinolone
Unique side effects of epidural triamcinolone?
Used to treat lumbar disc disease
Muscle weakness
Sedation
Anorexia
What is Conn’s syndrome?
Too much aldosterone
Primary - from adrenal gland
Secondary - from renin secreting tumor
s/sx of increased mineralocorticoids
-HTN from Na and water
-Hypokalemia from wasting
- Metabolic alkalosis from H wasting
High intake of what food resembles hyperaldosteronism?
Long term licorice ingestion (glycyrrhizic acid)
Treatment for Conn’s?
Aldosterone antagonists (spironolactone or eplerenone)
Potassium supplementation
Na restriction
Removal of aldosterone secreting tumor