Diabetes Type 1 Flashcards
What is diabetes type 1 due to?
Pancreas stops producing insulin
What is diabetes type 1 caused by?
The cells of the body cannot take glucose from the blood and use it for fuel
So the level of glucose in the blood keeps rising, causing hyperglycaemia.
What does type 1 diabetes result in?
Hyperglycaemia
What is normal blood glucose?
4.4-6.1mmol/l
What is insulin?
Anabolic hormone
What is insulin produced by?
Beta cells in the Islets of Langerhans in the pancreas
What is the function of insulin?
Reduce blood sugar levels
How does insulin work in the cells?
It causes cells to absorb glucose from the blood and use it as fuel
How does insulin work in the muscles?
It causes muscle and liver cells to absorb glucose from the blood and store it as glycogen
What is glucagon?
Catabolic hormone
What is glucagon produced by?
Alpha cells in the Islets of Langerhans in the pancreas
What does glucagon cause?
Glycogenolysis
Gluconeogenesis
What is glycogenolysis?
Liver breaks down stored glycogen into glucose.
What is gluconeogenesis?
Liver converts proteins and fats into glucose
Why does ketogenesis occur?
When there is an insufficient supply of glucose, and glycogens stores are exhausted
When does ketogenesis occur?
Prolonged fasting
What is ketogenesis?
The liver takes fatty acids and converts them to ketones
What are ketones?
Soluble fatty acids that can be used as fuel
What is a distinctive feature about someone with ketosis?
Acetone smell on their breath
How many new type 1 patients present with DKA?
50%
What are the symptoms of a DKA?
- abdominal pain
- polyuria, polydipsia, dehydration
- Kussmaul respiration
- acetone-smelling breath (‘pear drops’ smell)
What is kaussmal respiration?
Deep hyperventilation
What are other presentations of hyperglycaemia?
- Polyuria
- Polydipsia
- Weight loss
How is type 1 diabetes diagnosed?
Dip urine for glucose and ketones
What would be measured low in type 1 diabetes?
C peptide
What is not useful to measure in type 1 diabetes?
HbA1c
What is the fasting glucose level for type 1 diabetes?
Fasting glucose greater than or equal to 7.0 mmol/l
What is the random glucose level for type 1 diabetes?
Random glucose greater than or equal to 11.1 mmol/l (or after 75g oral glucose tolerance test)
What anti-bodies are used to diagnose type 1 diabetes?
Antibodies to glutamic acid decarboxylase (anti-GAD)
Islet cell antibodies (ICA, against cytoplasmic proteins in the beta cell)
Insulin antibodies
Who are insulin antibodies more commonly found in?
Younger people rather than older people
When should HbA1c be monitored?
Every 3-6 months
What should the target HbA1c level be for adults?
48mmol/l
How often should someone with type 1 self-monitor their blood glucose?
4 times a day
Before a meal and before bed
When would someone with type 1 diabetes need to monitor their blood glucose more often than 4 times a day?
- Frequency of hypoglycaemic episodes increases
- During periods of illness
- Before, during and after sport
- When planning pregnancy, during pregnancy and while breastfeeding
What are the blood glucose targets on waking?
5-7 mmol/l
What are the blood glucose targets before meals and at other times of the days?
4-7mmol/l
What is the main insulin regime for adults with type 1 diabetes?
Multiple daily injection basal–bolus insulin
When would you consider prescribing metformin?
If the BMI >= 25 kg/m²
What is the target blood pressure for someone with type 1 diabetes with no albuminuria or metabolic syndrome?
135/85
What is the target blood pressure for someone with type 1 diabetes with albuminuria or 2 or more features of metabolic syndrome?
130/80mmHg
What medication can you give for the management of hypertension in type 1 diabetes?
ACE inhibitors
Angiotensin-II receptor antagonist (A2RBs)
A2RBs are preferred for black African or African-Caribbean diabetic patient
When would A2RBS be preferred in the treatment of hypertension?
Black African or African-Caribbean diabetic patient
How is a DKA diagnosed?
- glucose > 11 mmol/l or known diabetes mellitus
- pH < 7.3
- bicarbonate < 15 mmol/l
- ketones > 3 mmol/l or urine ketones ++ on dipstick
What is the management of a DKA?
Fluid replacement
Insulin
Correction of electrolytes
What fluid replacement is used for a DKA?
Isotonic saline
What insulin would be administered to someone with DKA?
intravenous infusion should be started at 0.1 unit/kg/hour
once blood glucose is < 15 mmol/l an infusion of 5% dextrose should be started
What would you give to someone with a DKA once their blood glucose is < 15 mmol/l?
Infusion of 5% dextrose
How would you correct electrolyte disturbance in a DKA?
serum potassium is often high on admission despite total body potassium being low
this often falls quickly following treatment with insulin resulting in hypokalaemia
if the rate of potassium infusion is greater than 20 mmol/hour then cardiac monitoring may be required
Which type of insulin should be continued and which type of insulin should be stopped?
Long-acting insulin should be continued
Short-acting insulin should be stopped
