9. Vascular Surgery Flashcards
Briefly describe arterial and venous circulation of the legs.
What is an atheromatous plaque made up of?
How is peripheral arterial disease defined according to the ABPI?
Define:
a) intermittant claudication
b) acute limb ischaemia
c) critical limb ischaemia
[Pic]
Cells (smooth muscle, macrophages and other WBC), extracellular matrix (collagen, elastin, PGs), lipids.
<0.9. Prevalence increases with age
a) pain in limb brought on by exertion, relieved by rest
b) sudden loss of blood to limb
c) rest pain (constant pain + opiate analgesia) + tissue loss (b/c blood supply so bad)
What are the 6 Ps of acute ischaemia?
What investigations would you do for peripheral arterial disease?
What are some risk factors for critical limb ischaemia?
Pain, pallor, paralysis, perishing cold, pulseless, painless (parasthesia).
- *Bloods** (anaemia, polycythaemia), U + Es (renal disease), lipids (dyslipidaemia),
- *ECG** (cardiac ischaemia), ABPI (normal = 1 - 1.2; PAD = 0.5 - 0.9; critical limb ischemia <0.5), CXR, arterial duplex USS, CTA.
Smoking, diabetes, HTN, hyperprolactinaemia, CRP, hyperhomocysteinemia, IHD, stroke, family history
What are the conservative, medical and surgical treatment options for critical limb ischaemia and PAD?
Conservative: lifestyle (exercise), stop smoking
Medical: risk factor optimisation:
- Diabetes control: reduce HbA1C by 1% = 21% reduction in complications
- Cholesterol control: simvastatin 40mg = 24% reduction in revasc HDL protective
- BP control: 26% reduction in events
- Anti-platelets: aspirin 75mg = 23% reduction in events
- Anti-oxidants and vitamins: omega-3 fish oils
Surgical: endovascular - percutaneous transluminal angioplasty - stents [Pic], open - surgical bypass, adjuncts. Amputation: for <3%, may relieve intractable pain and death from sepsis/gangrene
What are some risks and benefits of angioplasty?
What is usually the preferred surgical option for patients with CLI +/- life altering claudication?
What is an alturnative if a patient’s veins are not good enough for bypass surgery?
List some risks and benefits of bypass surgery.
Risks: failure to dilate, re-stenosis, surgical salvage, amputation, death, contrast anaphylaxis, renal dysfunction <24hrs
Benefits: minimally invasive, short stay, quick recovery, role of stenting
Bypass surgery (balloon isn’t as good with a long area). Femoral-popliteal bypass, femoral-femoral crossover, or aorto-femoral bypass grafts
Dracon - prosthetic tube (but doesn’t work as well), or PTFE - teflon tube so blood doesn’t stick as well
Risks: graft failure, MI, infections, limb loss, death
Benefits: save limb, retain independence, wound healing
If it works then it’s better than angioplasty!
Define aneurysm.
Distinguish between true aneurysm and false/pseudoaneurysm.
What are some congenital and acquired causes of aneurysms?
Localised dilation of an artery >50% its normal diameter.
True: abnormal dilatations involving all layers of the arterial wall
False: involve a collection of blood in the adventitia only, which communicates with the lumen e.g. after trauma
Congenital: weak area (berry), arterial dilation, connective tissue disorders (Marfans, Ehlers-Danlos)
Acquired: trauma (direct injury, irradiation), infection (non-specific bacterial, syphilis), degeneration (atherosclerosis)
NB: male to female = 9:1
Describe the pathology of an aneurysm
What are some risk factors for aneurysms?
What are the main symptoms and signs of an abdominal aneurysm?
Intimal atherosclerosis, mural thrombus, destruction of elastic lamellae. Inflammatory response due to imbalance: matrix-degrading proteinases ≠inhibitors (MMP/plasminogen activators).
Increased autoimmune response: cytokines, chemo-attractants, peptide growth factors
Family hx, ethnicity (N. Europeans), smoking, hypercholesterolaemia, HTN. NOT diabetes = protective against rate of aneurysm progression
Symptoms: Abdo pain (intermittant/continuous - radiates to back, iliac fossa or groins), back pain, collapse, shock
Signs: pale, sweaty, normotensive/hypotensive, tachycardic, tender abdo, expansile/pulsatile abdo mass, absent pulses
What are the single and double arrows pointing to in this CT?
What are the 3 indications for AAA elective surgery?
What are the risks of AAA surgery?
Single - vena cava.
Double - aneurysm in front of spine. Can see blood clot inside it.
1) AAA >5.5cm diameter
2) Rapid AAA enlargement (>1cm/yr)
3) Symptomatic AAA
Mortality, MI, multi-organ failure, paraplegia, haemorrhage, infections (wound/graft), fistulae, hernia (if weakness in artery wall, tend to get weakness in abdo wall)
Describe the 2 different types of surgery for AAA.
Who is screened for AAA in the UK, and how?
What is the link between AAA and popliteal aneurysms?
1. Elective surgery - open repair by inlay synthetic graft, may be straight or bifurcated. Open pt, clamp aorta above and below and stitch in graft. Claudication risk when put clamps on due to massive backpressure on heart
2. Endovascular repair - avoids major surgery. Insert endovascular stent via femoral artery to reinforce aneurysmal segment. Has less mortality, shorter hospital stay and can be percutaneous, but higher graft complications e.g. endoleak, needs lifelong surveillance, more expensive and re-interventions may be needed…
All men over 65. Single transabdominal US
50% with PA have an AAA; 10% with AAA have PA. 50% PA are bilateral
What can you see on this XR?
Extra bit to aortic arch - blood forced itself into gap between intima and adventitia = dissection
What is an aortic dissection?
What are the 2 different types?
How would you diagnose it?
What are the risk factors?
Blood splits the aortic media with sudden tearing chest pain (+/- radiation to back). As dissection extends, branches of aorta occlude sequentially leading to hemiplegia (carotid artery), unequal arm pulses and BP or acute limb ischaemia, paraplegia (anterior spinal artery), and anuria (renal arteries). If dissection moves proximally = aortic valve incompetence, inferior MI, cardiac arrest
Type A: 70%, dissections involve ascending aorta -> consider for surgery and urgent cardiothoracic advice
Type B: ascending aorta not involved -> may be managed medically
CTA (gold std), MRA, TEE
HTN, genetic, connective tissue
What are varicose veins?
What are some primary and secondary causes?
What is the pathology of VV?
Long, tortuous and dilated veins of the superficial venous system.
Primary: idiopathic - familial?, weakness of vein wall, congenital valve absence (v. rare)
Secondary: obstruction to venous outflow - DVT, foetus, ovarian tumour/cyst/fibroids, abdominal lymphadenopathy, pelvic cancer, ascites, iliac vein thrombosis, retroperitoneal fibrosis. Arteriovenous malformation (increased pressures). Constipation. Overactive muscle pumps.
Blood from superficial -> deep leg veins via perforator veins (perforate deep fascia) and at the sapheno-femoral and sapheno-popliteal junctions. Valves prevent blood passing deep -> superficial. If they’re incompetent = venous HTN and dilation of superficial veins
What are some risk factors for VV?
How would you examine/investigate VV?
What are some complications of VV?
Prolonged standing, obesity, pregnancy, family hx, COCP, previous DVT
Inspect skin (ulcers, eczema, haemosiderin deposits, thin skin etc.) Palpate veins for tenderness and hardness. Feel for cough impulse at SFJ. Auscultate over varicosities for bruits ( = AV malformation). Abdo and pelvis. Doppler US for flow in incompetent valves
Swelling (blood pools and plasma leaks out from vein into tissue = swollen ankles at end of day), discomfort, itching, varicose eczema (fine arterioles in skin close off = dry itchy skin), haemosiderin deposition (red cells leave vein due to high pressue, can’t reenter, die in 3m, iron oxidises and becomes rust coloured), lipodermatosclerosis [L pic], bleeding, ulceration [R pic]
What are the conservative, medical, endovascular and surgical treatment methods for VV?
_Conservative:_ **leg elevation**, **class 2 compression hosiery** (compression stockings - higher pressure at bottom than top). **Lifestyle** - lose weight, regular walks - calf muscle action aids venous return _Medical:_ **topical relief** _Endovascular:_ **radiofrequency ablation** (catheter into vein, heated to destroy endothelium and close vein), **endovenous laser ablation** (similar but laser), **injection sclerotherapy** (**liquid** (for varicosities below knee if no gross saphenofemoral incompetence) - injected at multiple sites and vein compressed for few weeks to avoid thrombosis OR **foam** injected via US guidance at 1 site, spreads rapidly through veins, damaging endothelium, more effective than liquid _Surgery:_ **saphenofemoral ligation** (Trendelenburg proceedure); **stripping from groin to calf**; **multiple avulsions**
What are some early and late complications of VV treatment?
What are some benefits of endovenous technology for VV tx?
Early: bleeding, bruising, discomfort, infection, DVT/PE (if immobile)
Late: recurrence, parasthesia (if damage nerves accidentally)
Improvements over vein stripping: short tx time, immediate ambulation, can be performed in physician’s office, less £, complications mild and infrequent
