Y3 - Diabetes Flashcards
What is the difference between T1DM and T2DM?
T1 is (autoimmune) destruction of pancreatic b-islet cells resulting in absolute insulin deficiency. T2 is insulin resistance/impaired insulin secretion due to b-islet cell dysfunction resulting in relative insulin deficiency.
T2 is to do with obesity and sedentary lifestyle
T1 presents in childhood, T2 presents in adulthood
T1 diagnosis is sudden, typically in DKA.
T2 is typically gradual with symptoms of hyperglycaemia.
What are some clinical features of diabetes mellitus?
polyuria polydipsia unexplained weight loss fatigue nocturia (secondary enuresis in kids) polyphagia recurrent UTI poor wound healing and skin infections eg staph, candidiasis
acanthosis nigrans (dark pigmentation of skin folds) suggests insulin resistance
What tests would you do to diagnose diabetes?
Hba1c threshold of 48mmol/mol (6.5%) or more
Fasting plasma glucose theshold of 7.0mmol/L or more
Oral Glucose Tolerance Test.
Measure 2 hour plasma glucose after 75mg oral glucose.
Threshold is Random plasma glucose of 11.1mmol/L or more
C-Peptide is an insulin precursor used to differentiate between t1 and t2.
Low in t1, normal/high in t2.
What are some microvascular diabetes complications?
Retinopathy
(and cataracts and glaucoma)
Diabetic Nephropathy
Peripheral Neuropathy
What are some macrovascular diabetes complications?
Cerebrovascular = Stroke/TIA risk
Cardiovascular = ACS risk
Peripheral vascular = venous ulcers, leaky vessels, slow wound healing etc
How would you initially manage T2DM?
Step 1 - Lifestyle!
Education with DESMOND (diet, exercise, etc)
BP target <140/80
Lipids give atorvastatin if Qrisk>10%
Diet management target = 48mmol/mol (6.5%)
Step 2 - add Metformin and aim for 48mmol
Step 3 - dual therapy metformin + DPP4i/Pioglitazone/SU/SGLT2i and aim for 53mmol (7%)
Step 4 - triple therapy metformin + SU + dpp4i/pilglitazone/sglt2i and aim for 53mmol
Step 5 - Metformin + SU + SLP1 mimetic
Monitor Hba1c at 3-6 monthly intervals
How would you manage someone who was metformin sensitive?
Step 1 diet/lifestyle etc
Step 2 - add dpp4i/ pioglitazone/ su
Aim for 53mmol
Step 3 - dual therapy of dpp4i/ pio/ su
Step 4 - insulin
What are the mechanisms of the diabetes drugs?
Insulin Metformin Sulfonureals (Gliclazide) Glitazones (Pioglitazone) Dpp4 Inhibitors (sitagliptin) SGLT2 inhibitors (-gliflozins) GLP1 agonists (-tides like liraglutide)
Insulin = replaces endogenous insulin
Metformin = increases insulin sensitivity, decreases hepatic gluconeogenesis
SU = stimulate b-cells to secrete insulin
Pio = activates PPAR-gamma receptor in adipocytes to promote adipogenesis and fatty acid uptake
DPP4I = inhibits GLP1 breakdown so increases incretin levels so inhibits glucagon secretion (increases insulin)
SGLT2I = inhibits reabsorption of glucose in kidney
GLP1A = incretin mimetic so inhibits glucagon secretion
What are some common side effects to diabetes meds?
Insulin Metformin Sulfonureals (Gliclazide) Glitazones (Pioglitazone) Dpp4 Inhibitors (sitagliptin) SGLT2 inhibitors (-gliflozins) GLP1 agonists (-tides like liraglutide)
Insulin = hypos, weight gain
Metformin = GI upset, met acidosis, lactic acidosis in hf, not in egfr<30
SU = hypos, weight gain, hyponatraemia, agranulocytosis, aplastic anaemia
Pio = weight gain, fluid retention (ContraIndicated in hf), bladder cancer
DPP4I = pancreatitis, GI (generally well tolerated tho)
SGLT2I = DKA, UTI, weight loss
GLP1A = Decreased appetite, weight loss
How would you diagnose DKA?
Symptoms = polydipsia, polyuria, weight loss, abdo pain/nausea, SOB, confusion or lethargy
Signs = fruity acetone breath, acidotic breathing (deep sighing = Kussmaul resp), signs of dehydration like reduced skin turgor
Blood glucose >11mmol/L
OR known diagnosis of dm
Ketones >2+
OR Blood ketones >3mmol/L
Bicarb<15mmol/L
OR Venous ph<7.3
How would you manage DKA? (geeky medics)
A-E obviously
6L fluid over 24 hours
- 2nd bag review K+ and add 20mmol/500ml if it is 3.5-5.5
IV Insulin 0.1unit/kg/hour
50units actrapid/insuman rapid in 50ml saline
Regularly monitor glucose
Give 10% glucose in 500ml when BM<14
How would you diagnose Hyperosmolar Hyperglycaemic State?
Only in T2DM
Hypovolaemia
Hyperglycaemia >30mmol/L
No significant hyperketonaemia (<3) or acidosis (PH>7.3, bicarbonate >15)
Osmolality >320mosmol/kg
How would you manage HHS?
0.9% NaCl over 36 hours
Give 10mmol/L/hr K+ and check after 2 hours.
If K+<5.5 give 20mmol in 500mls
Insulin 0.05units/kg/hr
if glucose not dropping 5mmol/L/hr
10% glucose at 62.5ml/hr if it is <14mmol/L.
Aim for 10-15mmol/L to avoid hypo and cerebral oedema
LMWH prophylaxis for dvt risk
How would you manage a hypo?
conscious = quick acting carb like juice or sugar
confused & conscious = 2 tubes of glucogel or dextrogel
unconscious = 75ml 20% dextrose IV OR img glucagon IM
Long acting carb when awake
