hypoglycaemia Flashcards
what is the definition of hyoglycaemia?
BM <4
which drugs can cause hypoglycaemia?
insulin
oral hypogycaemics eg sulfonylureas (most common)
alcohol excess
ACEis
salicylate poisoning
what is pituitary insufficiency?
when pituitary can’t produce 1 or more of its hormones
how can pituitary insufficiency cause hypoglycaemia?
if not enough GH or ACTH is produced
which hormones act to increase BM?
cortisol
adrenaline
GH
glucagon
what is galactosaemia?
genetic disorder that stops you breaking down galactose
what is an insulinoma?
tumour of pancreas that results in excess insulin being produced
how can non pancreatic neoplasms, eg fibroma and sarcoma, cause hypoglycaemia?
they release insulin growth factor 2 (IGF2) which lowers blood sugar.
what are the causes of hypoglycaemia?
drugs
affecting hormonal axes- pituitary insuffiency, adrenal inufficiency, CAH
direct lowering of BM -dumping syndrome, insulinoma, immune hypos, infections eg malaria, neoplasms
insufficient intake -starvation, galactosaemia
liver issues -severe liver failure, glycogen storage disease
how would you diagnose insulinoma?
in a fasted state, glucose <2.2, inappropriately high insulin, and high c-peptide.
what do c peptide levels mean?
For each molecule of insulin produced there is a molecule of c-peptide.
C-peptide is a useful marker of insulin production because c-peptide tends to remain in the blood longer than insulin.
what investigations would you do for ?insulinoma?
CT scan
if -ve-consider endoscopic USS
what is the treatment for insulinoma?
surgical removal of tumour
what are the autonomic symptoms of hypoglycaemia?
sweating
anxiety
hunger
tremor
palpitations
dizziness
what are the neuroglycopenic symptoms of hypoglycaemia?
confusion
change in behaviour
fatigue, drowsiness
weakness
slurred speech
seizures
coma
how long does it take the brain to recover after an episode of hypoglycaemia?
45 mins
what is the grading severity of hypoglycaemia?
grade 1: aware and can treat themselves
grade 2: needs assistance from others but can use oral therapy
grade 3: semi/un conscious, need IM or IV assistance from others
what is the whipple’s triad for diagnoses of hypoglycaemia?
1) signs and symptoms of hypoglycaemia
2) low BM
3) relief of sx with increased BM
what investigations can you do to explore the underlying cause of hypoglycaemia?
hba1c
TFTs -?pituitary issues
LFTs -?liver issues
U+Es
09:00 cortisol /short synacthen test -?adrenal insufficiency
blood and urine assays for sulfonylureas
plasma insulin, glucose, and c-peptide -?insulinoma
what is the management pathway for acute hypoglycaemia?
conscious and able to cooperate and swallow: 10-20g fast acting carb, preferably liquid, eg 200ml fruit juice
conscious, unable to cooperate, can swallow: glucogel/dextrogel squeezed into mouth (1-2 tubes of 10g)
check BM 10-15mins after oral treatments, max 3 oral treatments before moving to IM/IV
conscious and unable to swallow: glucagon IM (1mg if >8yo, 0.5mg if under)
unconscious: abcde approach, stop insulin therapy. if IV access available, IV glucose eg 10% dextrose over 15 min. if IV unavailable, IM glucagon.
once BM >4, long acting carbohydrate eg biscuits, sandwich, milk
what are some limitations to IM glucagon use?
has relatively slow onset of action and relies on glycogen stores -may not be suitable for those in starved states, liver disease, and young children. also doesn’t work of alcohol excess is the cause -liver ignores glucagon if there’s alcohol to worry about.
