Acute limb ischaemia
| Resting limb pain in vasculopaths or coagulopaths | |
|---|---|
| Etiology | Sudden ↓ limb perfusion = potential threat to limb viability. |
| Epidemiology | Risk factors: peripheral arterial disease, mostly platelet embolus; AF; think Virchow’s triad. |
| Clinical presentation | White, then mottled limb 6Ps – rest pain relieved by dependency (pain on passive movement = poor prognosis); paraesthesia, pallor (chronic ischaemia ⇒ ?compensatory vasodilation), perishingly cold. Time course: embolic causes = seconds/minutes; thombotic = hours/days, less severe presentation |
| Pathogenesis | |
| Diagnostic investigations | ABPI usually 0.2-0.4. ↑ K due to muscle ischaemia CT angio - check for aneuryms (as embolic source) Bilateral lower limb ischaemia → aortic dissection, saddle embolus |
| Management | Urgent vascular referral ➥ Analgesia – avoid NSAIDs ➥ 5000 units unfrax heparin (IV) ➥ Thrombolysis possible with rTPA ➥➥ risk major bleed, best for acute on chronic ➥➥ take up to 24h ➥➥ not necessarily definitive ➥ May lead to reperfusion syndrome |