endocrine surgery Flashcards
What is the function of endocrine glands
Secretion of hormones into the blood stream that act on target organs to maintain metabolic equilibrium
What stimulates the release of thyroid hormones
TRH released from the hypothalamus which stimulates TSH to be released from the anterior pituitary which then stimulates secretion of T4 and T3 from the thyroid gland
What is the effect of thyroid hormones
Increases in carbohydrate and lipid catabolism
Increased protein synthesis
Increase in basal metabolic rate
Growth and maturation
What arteries supply the thyroid gland
The superior thyroid artery which is a branch of the carotid artery
Inferior thyroid artery which is a branch of the thyrocervical trunk
What is thyrotoxicosis
Excess thyroid hormones circulating due to over-secretion from the thyroid gland (hyperthyroidism`0
How does Grave’s disease work
Antibodies mimic TSH bind to receptor and cause thyroid to keep producing T3/T4
What is goitre
Enlargement of the thyroid gland
What is the WHO classification for goitre
0- impalpable
1a- palpable - invisible on extension
1b - palpable - visible on extension
2 - visble
3 - visible at distance
What is pembertons sign
Shows that large goitre will affect the entire airway and venous return from the head which is positive in SVC syndrome (superior vena cava)
What are the complications of thyroidectomy
Bleeding
Hoarseness in voice - damage to recurrent laryngeal nerve
Hypocalcaemia - parathyroid damage
What is the sign for hypoparathyroidism
Chvosteck/ trosseau’s - tap on facial nerve as it passes through parotid goland and the face will begin to twitch
What are the different types of thyroid cancer
papillary, follicular, medullary and anaplastic
What does the medullary thyroid cancer arise from
C- cells which secrete calcitonin
What does the papillary, follicular and anaplastic thyroid cancers arise from
Follicular epithelial cells where thyroxine is synthesised
Where does thyroid cancer commonly metastasise to
lymph nodes, bone and lungs
What is the function of parathyroid glands
control calcium levels in the blood
What is the function of calcitrol
causes bone resorption and increases calcium reabsorption at the renal tubules
What are the three zones of the adrenal cortex
Zona glomerulosa
Zona fasciulata
Zona reticularis
What does the zona glomerulosa secrete
Mineralocorticoids - aldosterone
What does the zona fasciculata secrete
Glucocorticoids - cortisol
What does the zona reticularis secrete
Sex hormones - androgens and oestrogens
What does the adrenal medulla secrete
adrenaline and noradrenaline
What artery supplies the suprarenal gland
branches of the aorta
What is cushing’s syndrome
Excess glucocorticoids (Cortisol)
