Leg ulcer and oedema

Question 1

What are the causes of bilateral leg oedema (10)

Answer 1

• Heart failure
• Renal – nephrotic syndrome
• DVT
• Venous insufficiency
• Dependent oedema
• Hypoalbuminaemia
• Malnutrition – including protein-losing enteropathy
• Medications
• Pelvic compression – tumour / lymphoma
• Inflammation / infection
• Lymphoedema
• Myxoedema

Question 2

Which medications cause leg oedema? (3 cat)

Answer 2

Dihydropyridine CCBs

Vasodilators – e.g. hydralazine, minoxidil, alpha-blockers

Steroid based medications – flurocortisone, estrogen, progesterone, testosteron, androgens

Question 3

In which group of patients the fluid removal of 2-3L (or even more) in 24 hours can be accomplished with diuretics, without clinically significant reduction in plasma volume (i.e. Azotemia - inc in Cr/Urea)? - (3 groups)

Answer 3

1. Heart failure
2. Nephrotic syndrome
3. Primary Sodium retention

This is because the oedema can be effectively mobilised since most capillary beds are involved (in contributing to oedema), in contrast with patients with cirrhosis without significant ascites but no peripheral oedema (where ascitic fluid can only be mobilised via peritoneal capillaries)

Question 4

In which 2 groups of patient with fluid overload aggressive diuresis would result in Azotemia?

Answer 4

1. Cirrhotics or malignant ascites - ascites without leg oedema.

• In these patients, excess ascitic fluid can only be mobilized via the peritoneal capillaries.
• Direct measurements have indicated that 300 to 500 mL/day is the maximum amount that can be mobilized by most patients.
• If the diuresis proceeds more rapidly, the ascitic fluid will be unable to completely replenish the plasma volume → resulting in azotemia and possible precipitation of the hepatorenal syndrome

2. Localised oedema due to venous or lymphatic obstruction

Question 5

Differential diagnosis of foot ulcers? (5)

Answer 5

• Arterial
• Venous
• Neuropathic (diabetic)
• Traumatic
• Malignant

Question 6

Arterial vs. Venous vs. Neuropathic leg ulcers. How are they differ in locations from which they arise?

Answer 6

• Arterial: over malleoli (over the bony prominence), base of heel, pressure points, anterior shin, toe joints
• Venous: area above medial & lateral malleoli, posterior calf, can be large / circumferential
• Neuropathic: plantar surface of the foot, pressure points, over meta-tarsal heads

Question 7

Arterial vs. Venous vs. Neuropathic leg ulcers. How are they differ in terms of their appearance?

Answer 7

• Arterial: base is dry, often pale or necrotic (brown/black fibrous tissue). Irregular margin
• Venous: base is pink or red, maybe covered with yellow fibrinous tissue and exudate is common. Large and sometimes circumferential
• Neuropathic: punched out, red base. _Calloused borde_r.

Question 8

What other features are helpful that can distinguish neuropathic ulcers from others? (3)

Answer 8

Neuropathic ulcers are:

Painless (where as arterial/venous = usually painful)

Sensations are absent

Associated with foot deformities

Reflexes are absent

Question 9

What is your general approach in managing wound?

Answer 9

Goal

• Identify and manage underlying aetiology
• Minimize symptoms: pain, itching, odour, bleeding
• Prevent infection
• Maximise healing

Acknowledge this is difficult management issue that requires MDT approach – wound CNC, surgeons, medics, podiatrist…etc

C: review diagnostic investigation re: underlying cause.

A: Identify associated conditions / secondary causes and treat

• Infection (wound culture, Abx, consider debridement of biofilm)
  
  • Rule out abscess and osteomyelitis
• Peripheral vascular disease
  
  • Arterial doppler
  • Consider revascularization

T: non-pharm

• Education: the importance of hygiene, diabetes control, identifying signs of infection
• life-style: smoking (impairs wound healing), encourage exercise/diet to improve BGL control
• Offload pressure points – foot orthoses, consider correcting deformities such as hammertoe, bunion, Charcot
• Dressings: non-adherent (so that it’s not painful when it is being changed) + absorptive dressing on the top (minimise exudate + odour)
• Consider debridement if devitalized tissues present
• Compression dressings (only for venous stasis ulcers)

T: Pharm

• Topical ABx
• Topical sucralfate + silver nitrate (bleeding)
• Dakin solution to aid odour
• Moisturizing cream
• Topical steroids
• Debridement (to prepare wound bed - removes local barriers to wound healing) followed by Vac dressing/pump (-ve pressure wound therapy), which promotes graduation tissue.