Perioperative Diabetes

Question 1

What happens during the surgical stress response?

Answer 1

Elevation of
- Catecholamines
- Growth hormone
- Glucagon
- Cortisol
Decreased insulin
Insulin resistance

Question 2

What are the consequences of hyperglycaemia in the context of surgery?

Answer 2

Increases wound infection
Impairs wound healing
Worsens outcome after neurological damage and myocardial ischaemia
Induces osmotic diuresis >
- Dehydration
- Electrolyte disturbance
T1D and rarely T2D can develop diabetic ketoacidosis

Question 3

What are the consequences of hypoglycaemia in the context of surgery?

Answer 3

Coma
Arrhythmias
Cognitive deficit
Increased mortality

Question 4

How do you evaluate a patient with diabetes before surgery?

Answer 4

What type of diabetes - do they need insulin or not?
Who’s primary medical professional caring for patient?
Current management
Adequacy of control
Complications of diabetes
Other risk factors for cardiovascular disease

Question 5

What is the aim for HbA1c?

Answer 5

7% or less

Question 6

What may it mean if a diabetic has a HbA1c of 6%?

Answer 6

HbA1c is an average

In this case, they may be having a lot of hypos

Question 7

What are the metabolic complications of diabetes?

Answer 7

Ketoacidosis

Non-ketotic hyperosmolar coma

Question 8

What are the large vessel complications of diabetes?

Answer 8

Myocardial ischaemia
Cerebrovascular disease
Peripheral vascular disease

Question 9

What are the microvascular complications of diabetes?

Answer 9

Nephropathy

Retinopathy

Question 10

What are the neuropathic complications of diabetes?

Answer 10

Peripheral neuropathies

Autonomic neuropathies

Question 11

What are the principles guiding perioperative management of diabetes?

Answer 11

Minimally invasive surgery
Regional anaesthesia to decrease stress response
Stop oral anti-hyperglycaemic and non-insulin medications when fasting
Regular blood glucose measurement
Insulin therapy plan to control blood glucose whilst fasting
Return to normal diet and medications ASAP after surgery

Question 12

What are the principles of managing blood glucose perioperatively?

Answer 12

Define whether perioperative control has been adequate
Monitor BGL regularly
Administer insulin and glucose until patient can tolerate diet and have their normal medication

Question 13

How may you manage type 2 diabetes that’s diet-managed perioperatively?

Answer 13

Early morning case if practical
No therapy needed
Check BGL pre-, intra- and post-operatively
Supplemental short-acting insulin if BGL over 10 mmol/L

Question 14

How may you manage type 2 diabetes perioperatively?

Answer 14

Early morning case
Oral medication
- Cease 12 hours pre-operation
- Monitor BGL 1-2 hourly and treat if <4 or >10 mmol/L
- May need insulin supplementation
- Resume oral agents when back to normal diet
Insulin requiring
- As for T1D

Question 15

How may you manage type 1 diabetes perioperatively?

Answer 15

Morning surgery
- Measure BGL every hour from waking
- Give usual dose of long-acting insulin
- Omit rapid/short-acting insulin
- Aim for BGL of 5-10 mmol/L
- Rapid-acting insulin to control BGL >12 mmol/L
Afternoon surgery
- Light breakfast with dose of long-acting insulin and half of short-/intermediate-acting insulin
- Monitor BGL every 1-2 hours
- Aim for BGL of 5-10 mmol/L
- Rapid-acting insulin to control BGL >12 mmol/L