Cardiovascular 2 Flashcards
What is an acutely ischaemic leg?
Severe, symptomatic hypoperfusion of a limb occurring for <2 weeks
The features of ischaemia are increased because of the absence of a developed collateral circulation
What are the common symptoms of acute leg ischaemia?
6 Ps: Pain Paraesthesia Pallor Pulseless Paralysis Perishingly cold
In real life if the limb haslost motor and sensory functionthen it is almost certainly unsalvageable so these signs are not particularly useful if you want to try and save the limb!
How can you differentiate between embolic or thrombotic causes of acute leg ischaemia?
Embolic cause - normal pulses in contralateral limb
Thrombotic cause - absent pulses in contralateral limb due to peripheral vascular disease
What are some signs of chronic vascular insufficiency?
Muscle wasting
Hair loss
Ulceration
What is the management for acute leg ischaemia in a viable non-threatened limb?
- Anticoagulation with IV heparin
- Urgent angiography to localise the site of the occlusion
- Revascularization procedure
within 6–24 hours
What are the first and second line methods of revascularisation in acute limb ischaemia?
First-line: catheter-directed thrombolysis (alteplase) and/or percutaneous mechanical thromboembolectomy (e.g., balloon catheter embolectomy)
Second-line: open thromboembolectomy
What organisms typically cause cellulitis?
- Streptococcus pyogenes (Group A Strep - beta-haemolytic streptococci) - most common (75%)
- Staphylococcus aureus
What are the risk factors for cellulitis?
Venous insufficiency Diabetes Immunocompromised Steroid use IVDU Obesity Alcoholics
How does cellulitis present?
Painful, swollen, erythematous, warm area
Poorly defined margins
Lymphangitis - red streaks radiating from skin lesion and following direction of lymphatic vessels
Lymphadenopathy
Systemic symptoms e.g. fever
What anaerobic organism can cause cellulitis? What sign is indicative of this?
Clostridium perfringens
Crepitus
How do you treat cellulitis?
Abx for 7 days PO (admit and give IV if severe)
Flucloxacillin 500mg PO QDS
Give phenoxymethylpenicillin or benzylpenicillin if strep confirmed
Erythromycin if penicillin allergic
How does a DVT present?
Unilateral localised pain in the calf that is throbbing in nature and occurs when walking or weight-bearing Calf swelling Tenderness Red, warm, oedematous leg Superficial vein distention
What is the name of the diagnostic score for DVT? Name the clinical features that score points
Well’s diagnostic algorithm
Clinical features that scores points:
- Active cancer
- Paralysis or recent plaster immobilisation of the leg
- Recent major surgery (within last 12 weeks) or being bedridden for 3+ days
- Local tenderness in calf
- Entire leg swollen
- Calf swelling >3cm compared with asymptomatic leg
- Pitting oedema in symptomatic leg
- Collateral superficial veins (non-varicose)
- Previous DVT
(score one point for each of following + subtract 2 points if alternative cause is considered at least as likely as DVT)
What investigations can you do for suspected DVT depending on the Well’s score?
If Well’s score is less than 3, do a D-dimer within 4 hours.
If D-dimer is positive, US the leg
If Well’s score is 3+, US the leg within 4 hours
What are the signs of PE and a massive PE?
Tachycardia
Hypoxia
Tachypnoea
Breathlessness
Massive PE
- Hypotension
- Cyanosis
- Signs of right heart strain - raised JVP, parasternal heave, loud P2
What is the medical treatment for DVT?
DOAC - apixaban or rivaroxaban 10mg PO BD for 7 days then 5mg BD thereafter
OR
LMWH - tinzaparin or enoxaparin 1.5mg/kg/24hours for 5 days
Compression stockings
What is the mechanism of action of LMWH?
Heparins bind to antithrombin which accelerates inhibition of Factor Xa
What is the management of acute limb ischaemia in a threatened limb?
Emergency revascularisation procedure within 6 hours maximum
First-line: catheter-directed thrombolysis (alteplase) and/or percutaneous mechanical thromboembolectomy (e.g., balloon catheter embolectomy)
Second-line: open thromboembolectomy
Define the difference between provoked and unprovoked DVT
Provoked DVT = associated with transient risk factor (these risk factors can be removed, thereby reducing the risk of recurrence)
Unprovoked DVT = occurring in the absence of a transient risk factor (no identifiable risk factor or a risk factor that is persistent and not easily correctable e.g. cancer or thrombophilia)
What is the duration of treatment of a DVT/PE depending on the patient?
- Patients with a provoked DVT/PE should be treated with 3 months of DOAC/LMWH therapy
- Patients with an unprovoked DVT/PE should be treated with 6 months of DOAC/LMWH therapy
- Patients with a recurrence of a DVT/PE when already on anticoagulation may require anticoagulation therapy for life
- Patients with ongoing risk factors (e.g. antiphospholipid syndrome) may also require anticoagulation therapy for life
What are some contraindications to anticoagulants?
- GI ulceration
- Coagulation disorders
- Haemorrhage
- Recent stroke
- Recent surgery
Which vein is most commonly affected by superficial thrombophlebitis?
Saphenous vein (and its tributaries)
Name some risk factors for superficial thrombophlebitis. Which is the most common?
- Varicose veins - most common
- Thrombophilia
- IV cannulation
- Pregnancy
- Cancer
How does superficial thrombophlebitis present?
Pain Itching Reddening of the skin Hardening of surrounding tissue Symptoms usually last a couple of weeks
How is superficial thrombophlebitis managed?
- NSAIDs/paracetamol for analgesia
- Self-care advice - warm moist towel to affected area; avoid immobility; elevate affected leg when sitting
- Compression stockings (after excluding arterial insufficiency)
- Can give an intermediate dose of LMWH for a month
What mainly causes peripheral arterial disease? What are some less common causes?
Atherosclerosis causing stenosis of the arteries
Others:
- Vasculitis
- Trauma
- Thromboangiitis obliterans (Buerger’s disease)
What is the most important risk factor for peripheral arterial disease?
Smoking
What classification is used for peripheral arterial disease?
- Asymptomatic
- Intermittent claudication
a. Claudication at walking distance >200m
b. Claudication at walking distance <200m - Ischaemic pain at rest
- Ulceration/gangrene