Revision - DKA, HHS & Hypoglycaemia Flashcards
(36 cards)
What electrolyte abnormality is typically seen in DKA?
Hypokalaemia
Triggers for DKA?
- 1st presentation
- missed insulin doses
- MI
- pancreatitis
- stress
What bicarb level is seen in DKA?
<15
Rate of insulin infusion given in DKA?
0.1 units/kg/hour
Mx of DKA?
1) IV saline infusion
2) Fixed insulin infusion 0.1 units/jg/hr
3) Add 10% dextrose to infusion once blood glucose <14
4) Correct electrolyte abnormalities
5) Stop short acting insulin, continue long acting
How does insulin affect potassium?
Causes potassium to be quickly taken up by cells, resulting in hypokalaemia.
What rate of potassium infusion requires cardiac monitoring?
if the rate of potassium infusion is greater than 20 mmol/hour
What blood ketone level defines DKA resolution?
<0.6
If the criteria for the resolution of DKA has been met, what else is required for the patient to be switched to SC insulin?
The patient is eating and drinking.
Who should the patient be reviewed by prior to discharge following DKA?
diabetes specialist nurse
Investigation of suspected cerebral oedema in DKA treatment?
CT head and urgent senior review
Clinical manifestations of cererbal oedema?
Headache, altered mental status, seizures, and focal neurological deficits
Define hypoglycaemia
Hypoglycaemia occurs when glucose concentration falls below the normal fasting glucose level.
Typically below 3.3 mmol/L.
What blood sugar level typically defines hypoglycaemia?
<3.3 mmol/L
What are the 2 main causes of hypoglycaemia in diabetes?
1) High insulin levels:
- patient has taken too much insulin
- has used the same amount of insulin whilst not eating enough or skipping a meal or snack.
2) Sulfonylureas (e.g. gliclazide): a common adverse effect, especially when starting this medication or increasing dose.
What diabetes drug typically causes hypoglycaemia?
Sulfonylureas e.g. gliclazide (as well as insulin)
What is the action of sulfonylureas?
Increase insulin secretion from beta cells of pancreas
How can hypopituitarism lead to hypoglycaemia?
There is a reduced secretion of GH from the pituitary (GH normally increases glucose production).
How can Addison’s disease lead to hypoglycaemia?
There is reduced adrenaline and cortisol from the adrenals (these hormones increase glucose levels).
Some normal physiological responses to hypoglycaemia:
1) Increased glucagon production by pancreas, reduced insulin production
2) Stimulates secretion of adrenaline from adrenal medulla
3) Stimulates secretion of GH from pituitary
4) Stimulate secretion of ACTH from the pituitary which stimulates cortisol secretion from the adrenal cortex.
What is Whipple’s triad?
Whipple’s triad aids the diagnosis of hypoglycaemia.
1) symptoms or signs of hypoglycaemia
2) low blood glucose
3) resolution of symptoms with the correction of blood glucose
What is an insulinoma?
a neuroendocrine tumour of the pancreas which causes unregulated secretion of insulin.
What further tests may be useful in diagnosing the cause of hypoglycaemia?
1) Serum insulin: elevated in insulinoma
2) Serum C-peptide: elevated in insulinoma or sulfonylurea use
3) Serum cortisol: reduced in adrenal insufficiency or hypopituitarism
4) TSH, U&E, LFTs: abnormalities help identify secondary causes of hypoglycaemia such as hypothyroidism, chronic liver disease or kidney disease.
What is pseudohypoglycaemia (idiopathic postprandial syndrome)?
A rare condition that presents with symptoms of hypoglycaemia after ingesting a meal, with a normal blood glucose level.
