Limb Ischaemia & DVT Flashcards
What is the key clinical feature of chronic limb ischaemia (i.e. peripheral arterial disease)? What is meant by this?
Intermittent claudication: calf/leg/buttock pain which occurs after a predictable amount of exercise, and settles with rest
The development of what symptom suggests that chronic limb ischaemia has progressed to critical limb ischaemia?
Severe ischaemic pain at rest
What are some complications of critical limb ischaemia?
Ulceration and/or gangrene
What investigation is used to diagnose and assess severity of chronic limb ischaemia?
ABPI calculation
What ABPI score would indicate intermittent claudication?
0.5 - 0.95
What ABPI score would indicate ischaemic pain at rest?
0.3 - 0.5
What ABPI score would indicate gangrene and ulceration?
< 0.2
What investigation is most useful in chronic limb ischaemia for confirming an occlusion?
Duplex US
What investigation is most useful in chronic limb ischaemia for surgical planning?
MR angiography
Most management of chronic limb ischaemia is conservative, and involves management of risk factors. When would interventional management be considered?
If symptoms are disabling, or if critical limb ischaemia occurs
What are some interventional management options for chronic limb ischaemia? If a patient isn’t suitable for these options, what should be done?
Angioplasty and stenting, resection or bypass grafting - if these can’t be done then amputation is necessary
What is acute limb ischaemia?
The sudden loss of blood supply to a limb
What are the two main causes of acute limb ischaemia? How common is each?
Thrombus formation from an existing atherosclerotic plaque (80%), or embolism, usually in AF (15%)
What are the 6Ps of acute limb ischaemia?
Pain, pallor, paraesthesia, perishingly cold, pulseless, paralysis
What investigations can be used to locate the occlusion in acute limb ischaemia?
Duplex US or CT
Describe the management options for acute limb ischaemia?
Thrombolysis, embolectomy, bypass surgery
What are some complications of acute limb ischaemia?
Irreversible ischaemia, gangrene, compartment syndrome
What condition may cause the ABPI to be falsely elevated, even with significant vascular disease?
Diabetes
What are some risk factors for DVT due to them causing stasis of blood flow?
Immobility, varicose veins, compression
What are some risk factors for DVT due to them causing hypercoagulability of blood?
Pregnancy, malignancy, inflammation, smoking, thrombophilias
What are some risk factors for DVT due to them causing endothelial damage?
Trauma and surgery
How can DVT be prevented in hospital patients?
LMWH injections and compression stockings
Half of cases of DVT are asymptomatic. How do they present if they are symptomatic?
Red, hot, swollen, tender calf
What are some differentials of a DVT?
Cellulitis, trauma, ruptured Baker’s cyst
What is the name of the scoring system used to assess the likelihood that a patient has a DVT?
Well’s score
A Well’s score of 3 or more suggests a 50% likelihood of DVT. What investigation is required?
Duplex US
A Well’s score of 2 or less suggests a 5-20% likelihood of DVT. What investigation is required?
D-Dimer
In all patients, regardless of Well’s score, what investigation investigation should be done if a D-Dimer comes back positive?
Duplex US
Describe the initial management of a DVT?
Therapeutic dose LMWH while receiving loading doses of warfarin, until the INR is within an acceptable range
How long should warfarin be given for after a DVT?
3-6 months
What are some potential complications of a DVT?
PE, post-thrombotic syndrome, venous ulcers
What are some signs of chronic venous insufficiency?
Leg swelling, increased pigmentation, lipodermatosclerosis, eczema and ulceration
What is the investigation of choice for confirming venous insufficiency?
Duplex US
What is the most common management option for chronic venous insuffiency?
Compression stockings
What is the gold standard investigation for diagnosing varicose veins?
Duplex US
When should patients with varicose veins be referred to surgery?
If they are symptomatic / if there are any skin changes
What medication is used to manage primary Raynaud’s?
Ca channel blockers
