Diabetes Mellitus Flashcards
Type 1 DM
beta cell destruction
absolute insulin deficiency
T cell mediated pancreatic islet B cell destruction
patients become symptomatic once 90% pancreatic B cells destroyed
Symptoms DM T1
polyuria polydipsia blurred vision weight loss in association with - glycosuria and ketonuria
Diagnosis DM T1
fasting glucose > 7 mmol/l OR
2 hour post prandial glucose > 11.1 mmol/l
confirm need measure specific antibodies
= islet antigen 2 antibodies and glutamic acid decarboxylase GAD antibodies
Diabetic ketoacidosis
CATABOLIC STATE
increased levels of counter regulatory hormones: catecholamines, cortisol, glucagon, growth hormone
absolute insulin deficiency = previously undx diabetic OR insulin injection omitted
relative insulin deficiency = stress situations, counter regulatory hormones increase response stress
Clinical features of DKA
Acidotic breathing Nausea Vomiting Abdominal Pain LOC Coma
Biochemical criteria for DKA
Diabetic with Hyperglycaemia >11mmol/l
Ketonuria
Acidotic with - Venous pH < 7.3 and Serum bicarb < 15 mmol/l
Management of DKA
IV fluids 0.9% saline (IV of 10-20ml/kg over hour) - degree fluid deficit 7.5-10% of body weight
use 0.45 or 0.9% saline depending corrected Na
insulin - 0.1unit/kg/hr
glucose to 11mmol/l = dextrose added IV fluids
movement of K+ form EC into IC space
K+ should added IV fluids - if renal fx is adequate
in HCU with frequent monitoring of vital signs and hourly glucose and electrolytes
First maintenance Insulin dose should be given 2 hours before discontinuing IV insulin infusion
NB - only give saline fluid boluses if pt is shocked (tachycardia and decreased BP)
K potassium
I insulin
N NGT in comatose
G glucose administration once serum level drops
F fluid infusion - corrected Na
U urea and creatinine mentoring every 4 hours
DO NOT GIVE BICARB
Cerebral oedema
serious but rare complication of DKA
- headache
- altered mental status
- vomiting
- hypertension
- inappropriate bradycardia
management: IV mannitol 1-2g/kg
Maintenance insulin dose
0.5 x total weight in kg = total daily insulin requirement (in units of insulin)
Dawn phenomenon
DOWN INSULIN
normal glucose until 3am then starts rise
hyperglycaemia on awakening due release counter regulatory hormones in pre-dawn hours - GH
reduced tissue sens to insulin 5-8am
endogenous insulin secretion decreased
Symogyi effect
SO MOch insulin
nocturnal hypoglycaemia leads surge of counter regulatory hormones (glucagon and epinephrine) that produce early morning hyperglycaemia - rebound hyperglycaemia
due excessive amounts exogenous insulin
Causes of Hypoglycaemia
stacking insulin excessive basal insulin delayed eating after takin mealtime insulin taking wrong insulin by mistake increased insulin sensitivity eating less carb than anticipated increased activity or exercise delayed gastric emptying fear of complications
Hypoglycaemia management
BG < 3.0 mmol/l - below 2.5 is pathological and requires investigation
child alert and fully conscious
- 10-20g given by mouth either in liquid (200ml milk) or as granulated sugar (2tsp)
- recheck glucose in 10-15 min and repeat if necessary
- further food prevent recurrence
unconscious or fitting
- Glucagon IMI or s/c <12 years 0.5mg; > 12 years 1mg
- if not effective in 10 minutes, IV glucose should be given
2-5ml/kg of 10% glucose iV infusion
Long term complications of DM
coronary artery disease diabetic myonecrosis peripheral vascular disease ischaemic stroke retinopathy neuropathy nephropathy cardiomyopathy encephalopathy
DM T2 - Features of insulin resistance
Hyperlipidaemia Hypertension Acanthosis Nigricans Non-alcoholic fatty liver disease Polycystic ovarian hyperandrogegism NB - can also present in DKA
