Aneurysms, Ischaemic Limb and Occlusions

• What is acute limb ischaemia (ALI)?


  It is a severe, symptomatic hypoperfusion of a limb, typically presenting for less than 2 weeks.
• How soon do you need to have intervention for acute limb ischaemia?

  It demands immediate intervention, ideally within 4-6 hours of presentation.
• What mnemonic summarizes the key signs and symptoms of ALI?


  The mnemonic "6Ps": pulseless, pain, pallor, paralysis, paraesthesia, and perishing cold.
• What are the important investigations for acute limb ischaemia?

  Complete blood count, U&E, group and save, clotting, and ECG.
• How does the management of ALI vary?


  It depends on the cause, with strategies differing for thrombotic and embolic causes.
• What is the annual incidence of acute limb ischaemia?


  Approximately 14 cases per 100,000 persons annually.
• In which population is acute limb ischaemia more prevalent?


  It is more prevalent in older populations, particularly individuals over the age of 60.
• What is the primary cause of thrombosis in acute limb ischaemia?


  Thrombosis often results from the rupture of atherosclerotic plaques.
• What is the typical onset of embolism in acute limb ischaemia?


  Embolism has a more acute onset.
• What are some external vascular compromises that can lead to acute limb ischaemia?

  Trauma and compartment syndrome.
• What are the risk factors for acute limb ischaemia?


  Smoking, diabetes, and cardiovascular disease (CVD).
• What happens if a limb has already lost motor and sensory function in acute limb ischaemia?


  It is generally considered unsalvageable.
• What are the differential diagnoses for acute limb ischaemia?

  • Peripheral vascular disease: Symptoms include claudication, atrophy, and slow wound healing.
  • Compartment syndrome: Symptoms include severe pain, pallor, paresthesia, pulselessness, and paralysis.
  • Deep vein thrombosis (DVT): Symptoms include unilateral leg swelling, pain, and redness.
  • Raynaud's phenomenon: Symptoms are episodic, including pallor, cyanosis, and rubor in response to cold or stress.
• What are the initial investigations for acute limb ischaemia?

  • Full blood count (FBC)
  • Urea and electrolytes (U&E)
  • Blood grouping and saving
  • Clotting profile
  • Electrocardiogram (ECG)
• What does the Rutherford Criteria Stage I indicate?


  Stage I indicates a viable limb with an arterial signal detectable by Doppler.
• What is indicated by Rutherford Criteria Stage IIa?


  Stage IIa indicates mild sensory deficit and no motor deficit.
• What does Rutherford Criteria Stage IIb signify?


  Stage IIb signifies severe sensory deficit, possibly with rest pain and motor deficit.
• What does Rutherford Criteria Stage III indicate?


  Stage III indicates an irreversibly non-viable limb, sometimes leading to amputation.
• What are the management strategies for thrombotic causes of acute limb ischaemia?


  • Angiography for incomplete ischaemia to map occlusion.
  • Endovascular procedures: angioplasty, thrombectomy, or intra-arterial thrombolysis.
  • Urgent bypass surgery for complete ischaemia.
• What are the management strategies for embolic causes of acute limb ischaemia?


  • Immediate embolectomy is required.
  • On-table thrombolysis may be considered if embolectomy fails.
• What is the treatment for a non-viable limb in acute limb ischaemia?


  Amputation and IV Heparin to prevent further thrombus propagation.
• What defines an aneurysm?


  A localized dilation of a blood vessel exceeding 50% of its normal diameter.
• What complications can arise from an aneurysm?


  Rupture or thrombosis.
• What are common presentations of an aneurysm rupture?


  Hypovolemic shock or ischemia.
• What imaging studies are primarily used for aneurysm investigations?


  Ultrasound, CT scans, and MRI.
• What are the management options for aneurysms?


  Observation, medical therapy, and surgical intervention depending on size and location.
• Where do most aneurysms commonly develop?


  In the abdominal aorta, thoracic aorta, cerebral arteries, iliac artery, femoral artery, and popliteal artery.
• What are the common risk factors for aneurysms?


  Age, smoking, hypertension, atherosclerosis, hyperlipidaemia, and genetic predispositions.
• What symptoms can result from a ruptured abdominal aortic aneurysm?


  Severe pain, hypovolemic shock, and sudden death in severe cases.
• What are the differential diagnoses for abdominal aortic aneurysms?


  • Aortic dissection: Sudden severe chest or back pain, often described as tearing.
  • Mesenteric ischemia: Severe abdominal pain, often postprandially.
  • Acute pancreatitis: Severe, persistent epigastric pain radiating to the back.
  • Renal colic: Colicky flank pain radiating to the groin.
• What are the differential diagnoses for thoracic aortic aneurysms?


  • Myocardial infarction: Chest pain or discomfort radiating to various areas.
  • Pneumonia: Fever, productive cough, and dyspnea.
  • Pulmonary embolism: Acute onset dyspnea, chest pain, and hemoptysis.
• What are the differential diagnoses for popliteal artery aneurysms?


  • Deep vein thrombosis (DVT): Pain, swelling, and erythema in the affected limb.
  • Baker's cyst: Posterior knee pain and swelling, occasionally with bruising.
• What are the differential diagnoses for cerebral aneurysms?


  • Migraine: Moderate to severe unilateral headache with photophobia.
  • Tension headache: Bilateral band-like pressure around the head.
  • Brain tumor: Persistent headache with focal neurological symptoms.
• What is the first-line investigation for suspected aneurysms?


  Ultrasound due to its non-invasive nature.
• What imaging studies provide detailed information about aneurysms?


  CT angiography or MRI angiography.
• What blood tests are relevant for aneurysm diagnosis?


  To assess for associated conditions such as hyperlipidemia and signs of rupture or ischemia.
• What is the management for small, asymptomatic aneurysms?


  • Observation and risk factor modification.
  • Lifestyle changes: smoking cessation, control of hypertension, healthy weight, regular exercise, low-sodium diet.
• What medical therapies may be used for aneurysms?


  • Antihypertensives and statins to reduce risk of expansion and rupture.
  • Anticoagulant or antiplatelet drugs to reduce thrombosis risk.
• What surgical options are available for larger or symptomatic aneurysms?


  • Endovascular repair (stent placement).
  • Open surgical repair.
• What is required for postoperative care following aneurysm repair?


  • Regular surveillance to monitor for complications or new aneurysms.
  • Imaging studies at regular intervals.