Chronic venous insufficiency of the lower legs — expanded notes
Pathophysiology
Venous valves prevent reflux and the calf-muscle pump propels blood proximally. Incompetent valves, venous obstruction or impaired calf pump function cause sustained venous hypertension. Increased hydrostatic pressure produces capillary leakage and oedema; red-cell extravasation leads to haemosiderin pigmentation. Chronic inflammation and tissue remodelling produce lipodermatosclerosis and ulceration.
Clinical spectrum
- Varicose veins and dependent oedema may precede inflammatory skin changes.
- Venous eczema causes itch, erythema, scaling and sometimes weeping around the lower legs.
- Haemosiderin causes brown pigmentation in the gaiter area.
- Lipodermatosclerosis causes induration and fibrosis, sometimes producing an inverted champagne-bottle leg.
- Atrophie blanche is ivory-white scar-like skin with surrounding telangiectasia and pigmentation.
- Venous ulcers are usually shallow, irregular and exudative, commonly near the medial malleolus.
Assessment
Examine pulses, temperature, oedema, varicosities, skin changes and ulcer characteristics. Duplex ultrasound evaluates reflux and obstruction. ABPI or toe pressure should be assessed before compression; ABPI may be falsely elevated in arterial calcification, particularly in diabetes. Consider mixed arterial and venous disease.
Management
Compression is central to treatment when arterial perfusion is adequate. Select compression strength according to vascular assessment and local protocols. Encourage walking, calf exercises, leg elevation, weight management and avoidance of prolonged standing. Treat venous eczema with emollients and appropriate topical corticosteroids. Use dressings that manage exudate; antibiotics are indicated only for clinical infection, not colonisation. Treat superficial venous reflux with endovenous ablation or other vascular intervention where appropriate.
Prevention
Long-term compression after ulcer healing reduces recurrence. Address mobility, obesity, skin care and early treatment of eczema or oedema. Reassess if pain, necrosis or ulcer deterioration suggests arterial disease or another diagnosis.