diabetes type 1 Flashcards
explain the pathology behind type 1 diabetes?
- pancreas stops being able to produce adequate insulin
- glucose isn’t taken up into cells so they think there’s no glucose available
- however, glucose levels in blood keep rising causing hyperglycaemia
what does type 1 diabetes present with?
- classical triad of symptoms of hyperglycaemia ( polyuria, polydipsia, weight loss)
- diabetic ketoacidosis
whats the underlying cause of type 1 diabates?
unclear
certain viruses may trigger it
whats the ideal blood glucose concenration?
4.4-6.1mmol/L
what process does insulin cause?
glycogenesis
what process does glucagon cause?
gluconeogenesis
explain the role of glucagon in glucose metabolism?
- alpha cells - islets of langerhans
- catabolic
- released in response to low blood glucose and stress
- tells liver to break down glycogen and releases it into the blood as glucose - glycoenolysis
- also tells liver to convert proteins and fats into glucose - gluconeogenesis
explain the role of insulin in glucose metabolism?
- hormone
- beta cells - islets of langerhans
- anabolic
- reduces blood sugar in 2 ways
- causes bodily cells to absorb glucose
- causes cells to store it as glycogen
explain the role of ketones in metabolism?
- released when low glucose stores
- made by the liver
- made from long chain fatty acids
- water soluble
- can cross blood-brain barrier
how can ketone levels be measured?
- urine - dipstick test
- blood - ketone meter
- acetone smell breath
what is the most common scanario for diabetic ketoacidosis to occur?
- type 1 diabetes
- type 1 diabetic with other illnesses eg infection
- type 1 diabetic who isnt sticking to their insulin regeime
what are the 3 key features for diabetic ketoacidosis?
- ketoacidosis
- dehydration
- potassium imbalance
the 3 key features of diabetic ketoacidosis are ketoacidosis, dehydration and potassium imbalance, explain why the ketoacidosis is present?
- without insulin body cells dont recognise glucose even tho its there in the blood
- liver will then start to produce ketones
- the kidney produces bicarb to buffer these but they get used up making the blood acidic
the 3 key features of diabetic ketoacidosis are ketoacidosis, dehydration and potassium imbalance, explain why the dehydration is present?
- hyperglycaemia overwhelmes the kidneys
- glucose leaks into the urine
- this pulls water with it
- causes polyuria and polydipsia
the 3 key features of diabetic ketoacidosis are ketoacidosis, dehydration and potassium imbalance, explain why the potassium imbalance is present?
- insulin normally drives potassium into cells
- no insulin so little potassium in cells
- blood potassium can either be high or normal bc the kidneys balance it
- however total body potassium is low because it isnt in cells
- patients develop hypokallaemia v quickly qhich can lead to arrhythmias
what is the pathophysiology of diabetic ketoacidosis?
- hyperglycaemia
- dehydration
- ketosis
- diabetic acidosis (with a low bicarb)
- potassium imbalance
what are the symptoms of diabetic ketoacidid?
- polyuria
- polydypsia
- nausea and vomitting
- acetone smelling breath
- dehydration
- weight loss
- hypotension
- altered consciousness
what is the diabetic ketoacidosis diagnosing criteria?
- hyperglycaemia - blood glucose over 11mmol/L
- ketosis - blood ketones above 3mmol/L
- acidosis - PH below 7.3