Flashcards in Diabetes Deck (33):
What are the types of diabetes?
• Type 1 DM
• Mature diabetes of the young (MODY)
• Type 2 DM
• Late onset autoimmune DM (LADA)
• Diabetes M secondary to pancreatic insufficiency, Coeliac, etc.
• Diabetes insipidus
diagnosing diabetes? HbA1c, Fasting glucose
HbA1C >48 mmol/L; fasting glucose > 7mmol/L
in what situation should we not rely on HbA1c?
Caution is needed when interpreting HbA1c in the presence of conditions affecting red blood cells or their survival time, such as haemoglobinopathies, or anaemia in the setting of other chronic diseases. The HbA1c in these patients often underestimates the degree of hyperglycaemia. Iron deficiency can cause a falsely elevated HbA1c. In these situations venous blood glucose concentration should be considered instead of HbA1c.
which groups of people require regular screening for type 2 diabetes?
-have intermediate hyperglycaemia
-have a history of gestational diabetes
-have polycystic ovary syndrome
-have clinical cardiovascular disease (eg acute myocardial infarction, angina, stroke)
-are taking antipsychotic medication.
what is the total daily insulin requirement for an average individual
The total daily insulin requirement for a healthy adult is about 0.5 to 0.8 units/kg.
what do we mean by basal insulin?
mandatory background insulin requirement over 24 hours independent of carbohydrate intake; typically 40% to 50% of the total daily insulin dose, achieved with once- or twice-daily long- or intermediate-acting insulin
what do we mean by bolus insulin?
—insulin required to cover carbohydrate intake; usually achieved with short- or very-short-acting insulin correction doses of insulin—supplemental insulin doses to return high blood glucose concentrations to acceptable levels; usually achieved with short- or very-short-acting insulin
Taken at meal times
blood ketones > __? may indicate DKA?
> 1.5mmol/L may indicate DKA so urgent hospital admission
how does a type 1 diabetic prevent hypoglycaemia during exercise?
increase caloric intake or reduce insulin dose
In a type 2 diabetic patient, what is the general HbA1c target?
less than 53 mmol/L
what is DPP4?
enzyme that breaks down GIP and GLP1
what are some autonomic neuropathic complications of DM?
bladder atony with urinary retention (and sometimes overflow) and asymptomatic or symptomatic urinary tract infection
cardiac autonomic neuropathy
what do we worry about with a diabetic with ACS?
silent MI- diabetic individuals sometime cannot 'feel' a heart attack (e.g. chest pain) and hence it goes undiagnosed and is associated with mortality
what are two groups of symptoms in hypoglycaemia?
Hypoglycaemia occurs in patients with diabetes when their blood glucose concentration falls below 4 mmol/L or is at a level low enough to cause symptoms and signs. I There are two groups of symptoms of hypoglycaemia:
-Adrenergic symptoms (mediated by the sympathetic nervous system) that include pale skin, sweating, shaking, palpitations and a feeling of anxiety
-Neuroglycopenic symptoms (due to altered brain function) that include hunger, suboptimal intellectual function, confusion and inappropriate behaviour, coma and seizures
what are some complications of hyperosmolar hyperglycaemia?
VTE and confusion
what is Diabetes insipidus?
Deficiency of ADH or insensitivity to its action on the kidney.
Leads to Polyuria, nocturia and polydipsia
what are the 2 categories of causes of Diabetes Insipidus?
Cranial or nephrogenic
what are some cranial causes of DI?
• Head trauma
• Iatrogenic- post surgical, post radioablation
• Vascular- aneursym/haemorrhage
what are some nephrogenic causes of DI?
• Drugs like lithium
how do we investigate for DI?
water deprivation test.
Describe a water deprivation test.
• Patient is deprived of fluid for 8 hours upon waking.
• Urine is monitored over that time. Body is weighed hourly.
• The test is seeing whether the patient is able to concentrate their urine over 8 hrs.
• In DI, unable to concentrate urine.
• Then, administer desmopressin to patient and monitor urine output for another 4 hours. This is to distinguish between cranial DI and nephrogenic DI.
• Cranial DI- after Desmopressin, urine begins to concentrate
• Nephrogenic DI- urine does not concentrate after desmopressin.
what is the mechanism of diabetic nephropathy?
glomerular hypertension leading to initially microalbuminemia and then ultimately end stage renal failure
what is an occasional complication/manifestation of peripheral neuropathy secondary to diabetes mellitus?
what do we want to investigate in someone with suspected T1 Diabetes?
look for anti GAD antibodies to islet cells. Glucose in the urine, dipstick, HbA1c, fasting blood glucose and random blood glucose test. If required, oral glucose tolerance test.
what are some atypical causes of diabetes?
chronic pancreatitis, surgical resection of pancreas, carcinoma of the head of pancreas, cystic fibrosis, cushings syndrome
what do we want to consistently monitor in a diabetic patient for nephropathy?
Blood pressure, microalbuminemia
how do we manage diabetic patients in surgery?
admit the patient overnight, give them evening meal. In the morning of surgery reduce basal insulin dose and start fasting. Apply sliding scale of insulin protocol. During the operation the anaesthetist is in control of this insulin protocol. Diabetic patients are always put first on the list.
when do we use sliding scale of insulin? what is it?
When the diabetic patient is sick and vomiting or perioperatively. The sliding scale of insulin is the administration of insulin that is tapered according to blood sugar levels.
when do T1 diabetic individuals have to closely manage their blood sugar levels?
when exercising, when fasting and when they are sick.
what are the HLA genes associated with Type 1 diabetes?
Associated with HLA DR3 +/- DR4
what is the difference between DKA and hyperosmolar hyperglycaemia?
Hyperosmolar hyperglycaemia is associated with very little ketosis. HHS is also more likely to have profound dehydration.
does the risk of hypoglycaemia in the elderly increase or decrease?
increased risk. This is because the compensatory stress response is impaired. So for example, with insulin, the glucose levels drop and normally adrenaline and catecholamines kick in to prevent hypoglycaemia. In the elderly, this response is impaired and the level of BSL at which unconsciousness ensues is higher. hence the risk of severe hypoglycaemic events is increased