Diabetic complications

Question 1

What are the two main mechanisms of diabetic foot disease?

Answer 1

• Neuropathy: resulting in loss of protective sensation
• Peripheral arterial disease (macro and microvascular ischaemia)

Question 2

How do patient present with diabetic foot disease?

Answer 2

• Neuropathy: loss of sensation
• Ischaemia:
  > absent foot pulses
  > reduced ABPI
  > intermittent claudication
• Complications:
  calluses
  ulceration
  Charcot’s arthropathy
  cellulitis
  osteomyelitis
  gangrene

Question 3

How often should we screen for diabetic foot disease?

Answer 3

Annually

Question 4

How do we screen for neuropathy and peripheral arterial disease in diabetic patients?

Answer 4

• palpating for both the dorsalis pedis pulse and posterial tibial artery pulse
• 10 g monofilament is used on various parts of the sole of the foot to test sensation

Question 5

Describe the difference between Mild to Moderate to High risk diabetic feet

Answer 5

Mild - calluses only

Mod - deformity/neuropathy or
non-critical limb ischaemia

High
- previous ulcer/amputation or
- neuropathy + non-critical limb ischaemia together
- neuropathy + callus/deformity
OR non-critical limb ischaemia + callus/deformity.

Question 6

Pathophysiology of DKA

Answer 6

• uncontrolled lipolysis (not proteolysis)

=> excess of free fatty acids that are ultimately converted to ketone bodies

Question 7

Most common precipitants of DKA

Answer 7

infection
missed insulin doses
myocardial infarction

Question 8

Presenting symptoms in DKA

Answer 8

• abdominal pain
• polyuria, polydipsia, dehydration
• Kussmaul respiration (deep hyperventilation)
• Acetone-smelling breath (‘pear drops’ smell)

Question 9

Diagnostic criteria for DKA

Answer 9

glucose > 11 mmol/l or known diabetes mellitus
pH < 7.3
bicarbonate < 15 mmol/l
ketones > 3 mmol/l or urine ketones ++ on dipstick

Question 10

Management of DKA

Answer 10

• 0.9% sodium chloride
• IV insulin (0.1 unit/kg/hour)
• once BM is < 14 mmol/l an infusion of 10% dextrose should be started at 125 mls/hr in addition to the 0.9%NaCl
• correction of electrolyte disturbance (particularly K+)
• long-acting insulin should be continued

Question 11

Complications which may occur from DKA itself or from the treatment given

Answer 11

• gastric stasis
• VTE
• arrhythmias secondary to hyperkalaemia/iatrogenic hypokalaemia
• cerebral oedema
• acute respiratory distress syndrome
• AKI

Question 12

Describe the distribution of sensory loss found in diabetic neuropathy

Answer 12

‘glove and stocking’ distribution,

• lower legs affected first due to the length of the sensory neurons supplying this area

Question 13

What medications are often used to treat painful diabetic neuropathy?

Answer 13

• amitriptyline
• duloxetine
• gabapentin
• pregabalin
• topical capsaicin if localised pain

> tramadol may be used as ‘rescue therapy’ for exacerbations of neuropathic pain

Question 14

Diabetic neuropathy can also cause gastrointestinal autonomic neuropathy. What symptoms does this cause?

Answer 14

Gastroparesis
> erratic BMs
> bloating and vomiting

Chronic diarrhoea
> often occurs at night

GORD
> decreased lower esophageal sphincter (LES) pressure

Question 15

How is gastroparesis treated in diabetic patients?

Answer 15

• metoclopramide
• domperidone
• erythromycin (prokinetic agents)