Peripheral Oedema
Overview
Swelling of one or multiple limbs - usually the legs - is a common presentation that may be due to cardiac, venous, lymphatic, musculoskeletal or metabolic pathology.
Aetiology
Pathophysiology
- Peripheral oedema occurs when the capillary filtration rate exceeds the lymphatic drainage rate.
- Capillary filtration is influenced by capillary hydrostatic pressure, plasma oncotic pressure and capillary permeability.
- Lymphatic drainage can be limited by obstruction.
Causes of Peripheral Oedema
Unilateral
- Impaired venous drainage - DVT, venous insufficiency, pelvic tumour
- Impaired lymphatic drainage - lymphoedema
- Cellulitis
- Musculoskeletal - soft tissue injury, fracture, compartment syndrome
Bilateral
- Volume overload - heart failure, liver failure, renal failure, pregnancy
- Right ventricular failure / pulmonary hypertension
- Impaired lymphatic drainage - lymphoedema
- Hypoalbuminaemia - malnutrition, malabsorption, nephrotic syndrome, liver (synthetic) failure
- Endocrine - pretibial myxoedema (profound hypothyroidism)
- Medications - NSAIDs, calcium channel blockers, aciclovir, cyclophosphamide, cyclosporine, corticosteroids, oestrogen, progesterone
History of Presenting Complaint
Distribution
Whether the swelling is unilateral or bilateral.- Unilateral swellingSuggestive of localised cause e.g. venous or lymphatic obstruction
- Bilateral swellingSuggestive of systemic cause
Timing
When the swelling started, whether it came on suddenly or gradually, and whether it comes and goes.- Sudden onset oedemaMore likely to represent a severe cause such as DVT
- Onset post traumaSuggestive of musculoskeletal cause
- Onset post surgeryRisk factor for DVT or iatrogenic lymphoedema
- Onset post commencement of new medicationSuggestive of drug-induced oedema
- Cyclical with menstrual cycleSuggestive of premenstrual oedema
Associated Symptoms
Whether the oedema is associated with any other symptoms.- Redness, warmth and tendernessSuggestive of cellulitis or DVT
- Chest painMay suggest heart failure with cardiac pain, or DVT with PE
- DyspnoeaSuggestive of heart failure or DVT with PE
- Significant weight lossRed flag for ?pelvic tumour causing venous obstruction
Severity
Ask about how the swelling is affecting the patient's day to day life. Some clues about severity can be:- Visible enlargement of the limb
- Difficulty in moving the affected limb(s)
- Clothes and jewelery no longer fit
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