Metabolic complications of diabetes

Question 1

What is biological definition of hypoglycemia?

Answer 1

Blood glucose level less than 3mmol/L

Question 2

In what groups of diabetics do hypos most commonly occur?

Answer 2

Type 1 diabetics

Type 2 diabetics on oral agents prone to hypos - sulpholylureas

Question 3

Early warning signs of hypoglycemia?

Answer 3

Sweating, palpitations, tremor, hunger, peri-oral paresthesia

Question 4

Late, dangerous signs of hypoglycemia?

Answer 4

Rapid loss of consciousness, stupor, coma

Question 5

Approach to treatments for mild hypoglycemia, typical dosages / foods used?

Answer 5

6 jelly beans
2 barley sugars
glass of lemonade
teaspoon of honet

Take one dose of one of the above, and don’t re-dose unless sx persisting 10 mins later

Question 6

Treatment of severe hypoglycaemia - e.g. unconscious patient

Answer 6

20-30mL 50% glucose IV until fully conscious

Can instill rectally with nozzle of syringe if IV access difficult

Admit if necessary - often not
Follow by ascertaining reason for the hypo
Provide patient education

Question 7

Typical presentation / sequale of symptoms and signs in diabetic ketoacidosis

Answer 7

Usually develops over a few days, but over a few hours in ‘brittle’ diabetics

2-3/7 Hx of polyuria, polydipsia, drowsiness

Acutely: nausea and vomiting, abdominal pain
Hyperventilation (severe acidosis - acidotic breathing)
((Note: ketotic breath))
Kentonuria

Question 8

What group of diabetics commonly seems to present in ketoacidosis?

Answer 8

Only in type 1 DM

Poorly controlled, or wrong doses recently

OR

**During illness - often with gastroenteritis - and thus have omitted their usual insulin dosages (a big no-no-no-no-no)

Question 9

Key management principles in diabetic ketoacidosis

Including any investigations you would do along the way

Answer 9

Dehydration correction is paramount - will kill before hyperglycemia

1) IV access, saline 0.9%. 1 L stat, then 1 L over next hour - follow fluid replacement guidelines. Include K+ replacement (see guidelines)

2) Check plasma glucose - usually going to be >20mmol/L in DKA
If so, give soluble insulin 10units IV

3) Insert NG tube if has been vomiting / is unconscious

4) Investigations:
Bloods - lab glucose, U&E, HCO3-, osmolarity, blood gases, blood cultures, FBC.
Urine tests - Ketones, MSC.
CXR(?)

5) Sliding scale of insulin (see guidelines)
6) Hourly checks of glucose, U&E, HCO3- to monitor and guide ongoing management

Question 10

Diagnostic criteria DKA?

Answer 10

Ketosis - e.g. ketouria on urinalysis. Ketotic breath test.

Acidosis: pH

Question 11

What is hyperosmolar hyperglycemia?

Answer 11

Marked hyperglycemia and dehydration, but without ketoacisosis

Question 12

In whom does hyperosmolar hyperglycemia typically occur?

Answer 12

Uncontrolled Type 2 Diabetics

Especially elderly patients

Sometimes previously undiagnosed diabetics

Sometimes underlying infection - e.g. pneumonia, UTI

Question 13

Typical presentation / symptom sequale in hyperosmolar hyperglycemia

Answer 13

Often insidious onset over days-weeks of fatigue, polydipsia, polyuria

Pts present in varying degrees from stupor, altered mental state, to coma

Question 14

Key findings from investigations in hyperosmolar hyperglycemia?

Answer 14

Extreme hyperglycemia

High plasma osmolarity (dehydration)

Question 15

Management of hyperosmolar hyperglycemia

Answer 15

1) IV fluids –> saline, slow infusion

2) Insulin –> relatively lower doses than acidosis

Question 16

Presentation and typical patient presenting with lactic acidosis

Answer 16

Marked hyperventilation - “air hunger”
Confusion

Consider in diabetics on metformin - especially if impaired renal function

Question 17

Investigations to diagnose diabetic lactic acisosis

Answer 17

ABGs: look for low pH 5mmol/L
High anion gap

Absent serum ketones