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
Where is intermittent claudication depending on the artery affected in peripheral arterial disease?
Femoral/popliteal arteries (most common) - calf claudication
Aorta and iliac artery (Leriche syndome) - level of aortic bifurcation or bilateral occlusion of iliac arteries
Clinical triad of: bilateral buttock/hip/thigh claudication, erectile dysfunction and absent/diminished femoral pulses
Tibial and fibular arteries - foot claudication
What are some features of critical limb ischaemia?
- Ulceration
- Gangrene
- Pain at rest
What clinical examination can be done in peripheral arterial disease?
Buerger’s test - leg goes pale when raised (if less than 20 degree angle, it is severe ischaemia)
What investigation is done for peripheral vascular disease? Describe how you would do this
ABPI
- Position patient at 45 degrees
- Allow patient 20 mins rest before procedure
- Record brachial BP in each arm and take highest
- Record dorsalis pedis BP then record posterior tibial BP and take highest of the 2
- Repeat on other leg
ABPI = Highest of ankle BP / highest of arm BP
What ABPI ratios indicate what?
1.0 - 1.2 = normal
<0.9 = peripheral arterial disease
<0.5 = critical limb ischaemia
What can cause falsely high results in ABPI?
Incompressible calcified arteries
What is the medical management of peripheral vascular disease?
- Clopidogrel 75mg OD (aspirin second line)
- Artovastatin 80mg ON
- Naftidrofuryl oxalate (peripheral vasodilator) - alleviates pain; only prescribe if patient does not want to be referred for surgery
What are the surgical options for managing peripheral vascular disease?
- Percutaneous transluminal angioplasty - balloon inflated in narrowed segment
- Surgical revascularisation - bypass graft
- Embolectomy - if acute limb ischaemia
- Amputation - last resort but can prevent death from sepsis and gangrene
What is a abdominal aortic aneurysm?
Localised permanent dilatation of the aorta >3cm
Define:
1) aneurysm
2) true aneurysm
3) false aneurysm
Aneurysm = abnormal dilatation of a blood vessel by >50% of its normal diameter
True aneurysm = dilatations that involve all layers of the arterial wall
False/pseudoaneurysm = collection of blood in outer layer only (adventitia) after trauma
What are the risk factors for AAA?
> 50 years - age-related changes in elastin, collagen and smooth muscle
Risk factors for developing atheroma in aorta:
- Hypertension
- Smoking
- Male
- Hyperlipidaemia
- Obesity
Genetic:
- Marfan’s
- Elher’s Danlos syndrome
- Collagen disorders
How are most AAA found?
Most are asymptomatic and found on routine abdominal examination, AXR or USS
How does an unruptured AAA present?
- Abdominal pain
- Back or loin pain
- Distal embolisation - limb ischaemia
How does a ruptured AAA present?
- Sudden onset of tearing epigastric pain in abdomen that radiates to back, groin, iliac fossa, testicles
- Shock and collapse
What sign is found on examination of AAA?
Pulsatile, expansile mass felt in abdomen above umbilical level
What investigation is diagnostic of AAA?
Abdominal USS
When is a CT angiogram warranted in AAA?
Warranted when at 5.5cm to determine suitability for endovascular procedures
What is the management of a AAA depending on the diameter?
3-4.4cm: yearly ultrasound
4.5-5.4cm: 3-monthly ultrasound
>5.5cm/expanding at >1cm/year: surgical repair
What are the surgical repair options for AAA?
- Open repair - midline laparotomy, segment is removed and replaced with prosthetic graft
- Endovascular repair - introducing a graft via femoral arteries and fixing the stent across the aneurysm
What is the acute management of a ruptured AAA?
ABCDE
- High flow oxygen 15L/min via a NRBM
- 2 wide bore cannulas in the antecubital fossae
- Bloods - crossmatch for 6 units, FBC, U&Es, glucose, coagulation, LFTs
- Give fluids in major hypovolaemia; aim to keep BP < 100 to prevent excessive blood loss
- IV morphine + IV antiemetics (50mg cyclizine)
- IV antibiotics (prophylactic) - 1.5g cefuroxime + 500mg metronidazole
- Call vascular surgeon and anaesthetist for open surgical repair (aortic cross clamping and insertion of Dacron graft)
What are the DVLA rules regarding AAA?
Any AAA >6.5cm requires notification to DVLA and disqualifies from driving until repaired
What are varicose veins?
Long, tortuous + dilated veins of the superficial venous system
What is the pathology behind varicose veins?
Normally, blood from superficial veins pass into deep veins via perforator veins and at the saphenofemoral + saphenopopliteal junctions
Valves prevent blood from passing from deep to superficial veins - if they become incompetent, there is venous hypertension + dilatation of superficial veins
What are the risk factors for developing varicose veins?
- Prolonged standing
- Obesity
- Pregnancy
- Family history
- Contraceptive pill
What are some secondary causes of varicose veins?
Obstruction - DVT, foetus, tumour
AV malformations
Overactive muscle pumps e.g. cyclists
Congenital valve absence
What signs might you see on examination of varicose veins?
- Oedema
- Venous eczema
- Ulcers
- Atrophie blanche - scar at site of healed ulcer
- Lipodermatosclerosis - skin hardness from fibrosis due to chronic inflammation and fat necrosis
- Fluid thrills felt at level of valve on tapping
What test assesses the veins in the leg? Describe how you would do it
Trendelenburg’s test
- Lift patient’s leg as high as comfortable to empty the veins
- Whilst their leg is elevated, place torniquet over saphenofemoral junction
- Ask patient to stand
- Rapid filling of varicosities with torniquet suggests incompetent perforator veins below levels of SFJ
How can you educate a patient about managing their varicose veins?
- Avoid prolonged standing
- Elevate legs when possible
- Wear compression stockings
- Lose weight
- Regular walks because calf muscles aid venous return
What endovascular treatments can be done for varicose veins?
Radiofrequency ablation - catheter inserted into vein and heated to ‘close’ the vein
Injection sclerotherapy - foam injected to damage endothelium of veins and occlude them
Surgery - stripping of veins
Where are arterial ulcers most common?
- At tips of toes or between toes
- Over phalangeal heads
- Above lateral malleolus
What does an arterial ulcer look like?
- Punched out lesion
- Well defined edges
- Black/necrotic tissue
- No exudate
Where are venous ulcers most common?
- Lower 1/3rd of leg
- Pre-tibial area
- Anterior to medial malleolus
What does a venous ulcer look like?
- Uneven edges
- Ruddy granulation tissue
- No dead tissue
- Exudate
Where are neuropathic ulcers usually seen?
- On sole of feet
- Under the heel
In which patients is mesenteric ischaemia most common?
Elderly patients with arterial/embolic disease
Which artery is the most common site of occlusion in mesenteric ischaemia? What does it normally supply?
Superior mesenteric ischaemia
Supplies:
- Distal duodenum
- Jejunum
- Ileum
- Right colon
What are the two types of mesenteric ischaemia depending on the degree of ischaemia?
Non-gangrenous (85%) - transient and self-limiting
Gangrenous (15%) - acute ischaemia with bowel infarction
How does non-gangrenous mesenteric ischaemia present?
Hyperactive phase
• Sudden severe cramping abdominal pain and guarding - worse after eating (may have weight loss due to avoiding eating)
• Pain is disproportionate to physical findings
• Nausea and vomiting
• Diarrhoea and maleana
Paralytic phase • Pain more diffuse • Bowel sounds become absent • Bloating • Bloody stools cease
How does gangrenous mesenteric ischaemia present?
- Acute abdomen with guarding and rebound tenderness - due to perforation and peritonitis
- Bloody diarrhoea
- Signs of shock
What is seen on ABG in mesenteric ischaemia?
Metabolic acidosis
What investigation is diagnostic of mesenteric ischaemia?
CT angiography
What is the surgical management of mesenteric ischaemia depending on whether the patient is haemodynamically stable or not?
Emergency laparotomy if haemodynamically unstable
- Open surgical embolectomy or mesenteric artery bypass
- Resection of necrotic bowel segments
Balloon angioplasty and stenting if haemodynamically stable
What should you suspect in someone with a DVT and neurological symptoms?
TIA - if patient has patent foramen ovale the clots that break off can get to the brain
What is post-thrombotic syndrome?
It is increasingly recognised that patients may develop complications following a DVT
Venous outflow obstruction and venous insufficiency result in chronic venous hypertension
The following features maybe seen:
- painful, heavy calves
- pruritus
- swelling
- varicose veins
- venous ulceration
