endocrinology Flashcards
What are the diagnostic criteria for DKA
ketonaemia>3mmol/l (or significant ketonuria)
Bloog glucose >11 (or known DM)
serum bicarbonate<15 or venous pH<7.3
when should 10% dextrose be added to rescutaition/replacemetn fluid in DKA?
when BM<14
what is the initial rate of fixed rate insulin in DKA?
0.1units per KG per hour
WHat are the diagnostic criteria for HHS?
clinical hypovolaemia
BM>30mmol/l without significant keonaemia or acidosis
serum osmolarity>320mmol/l
how is serum osmolality calculated?
2xNa +glucose +urea
what is the normal osmolar gap
10msom/kg
when should insulin infusion be started in HHS?
once BM is no longer falling with IV fluids alone
dose of glucagon in hypoglycaemia
1mg IM
which patients have reduced glycogen stores
alcoholics, sulphynourea, liver failure, malnourished
what is produced by the zona glomerulosa?
mineralocorticoids e.g aldosterone
what is produced by the zona fasciculata?
glucocorticoids e.g cortisol
what is produced by the zona reticularis?
androgens
what is produced by the adrenal medulla
catecholamines e.g. adrenaline/noradrenaline
biocehmical markers of adrenocortical insufficiency
hyponatraemia hyperkalaemia high urea/creatinine hypoglycaemia metabolic acidosis
low cortisol and low acth indicates?
secondary adrenal insufficinecy
low corstiol and high ACTH
primary adrenal insufficincy (addison’s disease)
principal cause of addision’s disease?
idiopathic/likely automimmune destuction
management of acute adrenocortical insufficiency
a to E resucitation, fluids as guided by cardiovascular status
hydrocorisone 100mg IV
fludrocorisone only in primary insufficneccy
monitor for hypoglycamia and treat if needed
treat any underlying infection
biochemical markes of cushing’s syndrpome
hypergy;ycaemia
hypokalaemia
hypernatraemia
most common cause of cushing’s syndorme
chronic glucocorticoid administration
cause of cushing’s disease
ACTH secreting pituitary tumour
treatement of cushing’s disease
removal of pituitary adenoma, if can’t be located, bilateral adrenalectomy
phaechromocytomas arise in?
adrenal medulla
diagnosis of phaeochoromocytoma?
24 hour urinary free catecholamine level
diagnostic imaging to localise tumour
best agents for BP control in phaeochromocytoma
phenoxybenzamine, (alpha blocade) then propranolol to treat tachycardia
how to calculate anion gap
sodium-chloride-bicarb
treatment of thyroid storm
high dose carbimazole/PTU then potassium iodide - inhibit synthesis and release
betablockers (80mg propanolol po) - stop peripheral conversion t4 to t3
sedation wwith benzos
glucocorticoid - stop peropherial conversion and prevent adc insufficinecy
-treat underlying cause, eg antibtics
supportive managemnt , e.g fluids or NGT
3 main features of myxoedema coma
altered mental state
hypothermia (or abscence of fever despite severe infection
presence of a precipitating event
managmetn of myxoedema coma
thyroid replacment
treat preciptant
100mg hydrocrotsone 8 hourly
supportive therapy
managment of pituitary apoplexy
hydrocortisone 100mg 6 hourly
supportive measures
neurosurgeons
features of diabetes insipidus
polyuria
poydipsia
dilute urine
dehydration
biochemical markers of DI
high plasma osmolality
low urine osmolality
high serum sodium
(deranged pituitary function tests and remember CT head)
treatment of cranial DI
desmopressin/DDAVP
ECG changes in hypocalcamiatreatment of hypocalcaemia
calcium gluconate, low thershold for magnesium sulphate
