- In claudication (chronic limb ischemia) Hx, it will be the same distance every time, not progressive, b\c fixed lesion
Classification of chronic limb ischemia depends on distance:
- Mild > 200 m
- Moderate 100-200 m
- Severe < 100 m
- If claudication + gangrene or ischemic ulcer -> chronic critical limb ischemia -> urgent revascularization
Six P’s of acute limb ischemia:
- Pain
- Pallor
- Perishingly cold
- Pulseless
- Paresthesia
- Paralysis
- Most are not severe enough to cause all 6 sx, the essential ones are the first 4 (pain, pallor, coldness, pulseless)
- No collateral circulation -> paresthesia and paralysis (the most severe signs)
- To assess severe ischemia -> ask pt to move toes, why? Short muscles are the first group to be affected by ischemia
- In acute severe type, you have less than 6 hrs to save the limb -> after 6 hrs:
- If there’s paresthesia and paralysis -> means SEVERE: complete cut of blood supply -> so you need revascularization w\in 6 hrs!
- If still no paralysis of paresthesia -> means MODERATE acute ischemia: there’s development of collaterals, limb can survive for 1 wk -> you have time, start with heparin then go for embolectomy
Acute limb ischemia
- Irreversible: severe + more than 6 hrs -> the pain disappears, still cold and absent pulse -> bad sign = dead limb (pain means viable limb) -> don’t revascularize -> demarcate and amputate
- Reversible:
- Threatened: severe + less than 6 hrs -> revascularize ASAP!
- Non-threatened: moderate + at any time “no golden hours” -> heparin + postpone intervention
How to describe an ulcer?
- Number
- Shape
- Dimensions
- Location
- Border
- Edge
- Floor
- Base
- Discharge
| ARTERIAL | VENOUS | NEUROPATHIC | |
| Location | Distal (web space, dorsum of the foot) | Medial malleolus (+lipodermatosclerosis) | Planter |
| Pain | + | +\- | – |
| Pulse | No pulses | Intact | Intact |
| Margins | Sharp | Irregular\sloping | Punched out |
Why differentiate types of gangrenes (chronic critical limb ischemia)? Both need revascularization:
- Wet gangrene: bacterial overgrowth + infection -> pt can go to septic shock -> so do minimal drainage of infection (to prevent sepsis) -> revascularization -> then do full debridement
- Dry gangrene: don’t intervene until revascularization first -> then amputate, why? You need good vessels for the stump to heal
Pedal pulses:
- Dorsalis pedis -> lateral to extensor hallucis longus
- Posterior tibial -> behind medial malleolus
Special tests in limb ischemia:
- Capillary refill: normal is < 2 secs
- Buerger’s test: lift leg passively -> until it turns pale or the pain disappears -> measure the angle:
- Normally lifting it to 90° -> no change (the smaller -> the worse)
Ankle-brachial index:
- Normal is > 0.9
- If absent pulse + ABI is 1.6 -> false result; can happen in some of diabetic pt b\c of heavy calcification -> measure the toe pressure (no calcification)
Wave form:
- Normal is triphasic (abnormal is biphasic or monophasic)
Venous drainage of lower limb:
- Superficial: Saphenous veins
- Deep: parallel to the artery
- Flow is from superficial to deep, controlled by valves and muscle contractions
- Superficial to deep: perforators
- Superficial to superficial: communicators
Varicose veins:
- ortious dilated veins along the course of great saphenous V
- Examined first by standing -> then ask the pt to lay down
- If disappears -> primary varicose veins -> means venous valve failure
- If doesn’t disappears -> secondary varicose veins -> means obstruction by DVT (post-thrombotic limb) (takes time to disappears b\c drains through tributaries)
Download the PDF version: here
References:
- Dr Kaialy’s lecture
