acute complications of diabetes - hypoglycaemia W6

Question 1

diabetic emergencies?

Answer 1

hypoglycaemia
diabetic ketoacidosis
hyperosmolar hyperglycaemic syndrome (HONK)
lactic acidosis (metformin)

Question 2

hypoglycaemia general points?

Answer 2

commonest diabetic emergency
most episodes treated at home
average type 1 diabetic experiences 1000s of mild episodes
1-2 episodes of severe hypoglycaemia per yr
severe = need for external assistance

Question 3

commonest causes of hypoglycaemia?

Answer 3

patient error (too much insulin, too little carbohydrate, missed/late meal, exercise)
alcohol
sulfonylureas (eg gliclazide, glipizide)

Question 4

what are sulfonylureas?

Answer 4

drugs that encourage beta cells to produce more insulin

Question 5

mechanism of action of SUs? (sulfonylureas)

Answer 5

binds to SUR1 on pancreatic beta cells, potassium ion channels close, K+ cannot leave the cell, leads to depolarisation. causes voltage gated Ca2+ channels to open, Ca2+ enters cell, causes exocytosis of insulin vesicles.

Question 6

other causes of hypoglycaemia?

Answer 6

decreased insulin requirements (eg weight loss)
liver disease, alcohol (reduction in hepatic gluconeogenesis)
conditions associated with T1DM
complications of diabetes

Question 7

conditions associated with T1DM that may cause hypoglycaemia?

Answer 7

coeliac disease
Addison’s disease
hypothyroidism
hypopituitarism

Question 8

complications of diabetes that may cause hypoglycaemia?

Answer 8

autonomic neuropathy
injection sites/lipohypertrophy
renal failure
counterregulatory failure

Question 9

counterregulatory response against hypoglycaemia

Answer 9

decreased insulin output
alpha cells of pancreas secrete glucagon, signals for liver to release more glucose.
adrenal glands secrete epinephrine, signals liver and kidneys to produce more glucose
epinephrine stops body tissues from using too much insulin.

if glucagon and epinephrine fail to raise blood sugar levels, cortisol and growth hormone are released.

Question 10

autonomic symptoms of hypoglycaemia?

Answer 10

sweating
shaking
palpitations
hunger

Question 11

neuroglycopenic symptoms of hypoglycaemia?

Answer 11

confusion
drowsiness
difficulty speaking
odd behaviour
incoordination

Question 12

non-specific (malaise) symptoms of hypoglycaemia?

Answer 12

nausea
headache

Question 13

features of hypoglycaemia symptoms in different age groups?

Answer 13

children - behavioural change
elderly - neurological symptoms, eg mimic stroke.

Question 14

what declines over time in type 1 diabetes? in what order?

Answer 14

counterregulatory hormones
glucagon then adrenaline then cortisol/growth hormones

Question 15

which symptoms occur at which levels of blood glucose? what is this affected by?

Answer 15

(mmol/l)
below 4 - sweating, tremor
below 3 - confusion, loss of concentration
1 - coma/seizure
below 1 - permanent brain damage

if patient is unaware of hypoglycaemia, set point is lower. symptoms only start below 3mmol/l blood glucose

Question 16

what causes reduced awareness of hypoglycaemia?

Answer 16

hypoglycaemia causes impaired physiological response to hypoglycaemia, leading to reduced awareness of hypoglycaemia, leading to increased vulnerability to further episodes of hypoglycaemia, leading to hypoglycaemia etc`.
!!vicious cycle!!

Question 17

diagnostic criteria of hypoglycaemia?

Answer 17

Whipple’s triad: 2 out of 3 of:
-typical symptoms
-biochemical confirmation
-symptoms resolve with carbohydrate

Question 18

management of hypoglycaemia?

Answer 18

if alert - give sweet drink or dextrose tablet (20g CHO)
if not alert - give 20% dextrose IV
if cant get IV access - give 1mg IM glucagon plus sweet drink (not effective in alcoholic hypo)

follow-up rapid acting carbs with slow release carbs
10% glucose infusion if long-acting insulin or SU
if recovery not rapid then consider other cause
full cognitive recovery can lag by 45 mins (driving!!)

Question 19

aftercare of hypoglycaemia?

Answer 19

follow up with starchy snack
discharge if made full recovery and responsible adult at home (but not if SU induced)
inform diabetics team
close monitoring of blood glucose for next 72 hrs
cut back on insulin doses if no obvious remedial cause.

Question 20

driving advice for drivers with insulin-treated diabetes?

Answer 20

carry glc meter/real time glucose monitoring/flash glucose monitoring and rescue carbohydrate
check glc before driving
test every 2hrs while driving
If glc is ≤ 5mmol/l, take a snack
if glc ≤4mmol/l, do not drive