Vascular Surgery Flashcards
modifiable and non modifiable atherosclerosis risk factors
Modifiable • Smoking • BP • DM control • Hyperlipidaemia • ↓ exercise Non-modifiable • FH and PMH • Male • ↑ age • Genetic
disease assoc with atherosclerosis and peripheral vascular diseae
- IHD: 90%
- Carotid stenosis:15%
- AAA
- Renovascular disease
- DM microvascular disease
intermittent limb claudication
Cramping pain after walking a fixed distance
• Pain rapidly relieved by rest
• Calf pain = superficial femoral disease (commonest)
• Buttock pain = iliac disease (internal or common)
critical limb ischaemia
Fontaine 3 or 4
• European working group definition (1991)
• Ankle pressure <50mmHg (toe <30mmHg) and
either:
§ Rest pain requiring analgesia for ³2 wks
- Especially @ night
- Usually felt in the foot
- Pt. hangs foot out of bed
- Due to ↓ CO and loss of gravity help
§ Ulceration or gangrene
Leriche’s syndrome
Leriche’s Syndrome: Aortoiliac Occlusive Disease
• Atherosclerotic occlusion of abdominal aorta and iliacs
• Triad
§ Buttock claudication and wasting
§ Erectile dysfunction
§ Absent femoral pulse
Buerger’s diseaes
Buerger’s Disease: Thromboangiitis Obliterans
• Young, male, heavy smoker
• Acute inflammation and thrombosis of arteries and
veins in the hands and feet → ulceration and
gangrene
clinical examination Buerger’s diseaes
• Pulses: loss of pulses and ↑ CRT (norm ≤2sec)
• Ulcers: painful, punched-out, on pressure points
• Nail dystrophy / Onycholysis
• Skin: cold, white, atrophy, absent hair
• Venous guttering
• Muscle atrophy
• ↓ Buerger’s Angle
§ ≥90: normal
§ 20-30: ischaemia
§ <20: severe ischaemia
• +ve Buerger’s Sign
§ Reactive hyperaemia due to accumulation of
deoxygenated blood in dilated capillaries
classification scores x 2 peripheral vascular diseas
Fontaine • Asympto (subclinical) • Intermittent claudication § >200m § <200m • Ischaemic rest pain • Ulceration / gangrene Rutherford • Mild claudication • Moderate claudication • Severe claudication • Ischaemic rest pain • Minor tissue loss • Major tissue loss
chonic limb ischaemia
Normal Doppler: triphasic
• Mild stenosis: biphasic
• Severe stenosis: monophasic
ABPI
claud at <0.8
rest pain at <0.6
ulcer/gangrene <0.3
NB. Falsely high results may be obtained in DM / CRF
due to calcification of vessels >1.4 ABPI
investigating suspected chronic limb ischaeia
Walk test
• Walk on treadmill @ certain speed and incline to
establish maximum claudication distance.
• ABPI measured before and after: 20% ↓ is sig
Bloods • FBC + U+E: anaemia, renovascular disease • Lipids + glucose • ESR: arteritis • G+S: possible procedure
Imaging: assess site, extent and distal run-off
• Colour duplex US
• CT / MR angiogram
• Digital subtraction angiography
§ Invasive \ not commonly used for Dx only.
§ Used when performing therapeutic
angioplasty or stenting
Other
• ECG: ischaemia
cons med surg mnagement chronic limb ischaemia
Conservative Mx
• Most pts. ¯c claudication can be managed conservatively
• ↑ exercise and employ exercise programs
• Stop smoking
• Wt. loss
• Foot care
• Prog: 1/3 improve, 1/3 stay the same, 1/3 deteriorate
Medical Mx
• Risk factors: BP, lipids, DM
§ β-B don’t worsen intermittent claudication but use
¯c caution in CLI
• Antiplatelets: aspirin / clopidogrel
• Analgesia: may need opiates
• (Parenteral prostanoids ↓ pain in pts. unfit for surgery)
Endovascular Mx
• Percutaneous Transluminal Angioplasty ± stenting
• Good for short stenosis in big vessels: e.g. iliacs, SFA
• Lower risk for pt.: performed under regional anaesthesia
as day case
• Improved inflow → ↓ pain but restoration of foot pulses is
required for Rx of ulceration / gangrene.
consdier surgical reconstruction if v v severe
surgical reconstruction of limb vasc PVD
if v bad claud on <100m walk
Pre-op assessment
• Need good optimisation as likely to have cardiorespiratory
co-morbidities.
Practicalities
• Need good proximal supply and distal run-off
• Saphenous vein grafts preferred below the IL
• More distal grafts have ↑ rates of thrombosis
Classification
• Anatomical: fem-pop, fem-distal, aortobifemoral
• Extra-anatomical: axillo-fem / -bifem, fem-fem crossover
Other
• Endarterectomy: core-out atheromatous plaque
• Sympathectomy: chemical (EtOH injection) or surgical
§ Caution in DM ¯c neuropathy
• Amputation
prognosis following chornic limb ischaemia or amputation
just FYI
1yr after onset of CLI • 50% alive w/o amputation • 25% will have had major amputation • 25% dead (usually MI or stroke) Following amputation • Perioperative mortality § BK: 5-10% § AK: 15-20% • 1/3 → complete autonomy • 1/3 → partial autonomy • 1/3 → dead
classify severity of limb ischaeia
• Incomplete: limb not threatened
• Complete: limb threatened
§ Loss of limb unless intervention w/i 6hrs
• Irreversible: requires amputation
causes of acute limb ischaemia
Thrombosis in situ (60%) § A previously stenosed vessel ¯c plaque rupture § Usually incomplete ischaemia • Embolism (30%) § 80% from left atrium in AF § Valve disease § Iatrogenic from angioplasty / surgery § Cholesterol in long bone # § Paradoxical (venous via PFO) § Typically lodge at femoral bifurcation § Often complete ischaemia • Graft / stent occlusion • Trauma • Aortic dissection
presentation of acute limb ischaemia
Pale • Pulseless • Perishingly cold • Painful • Paraesthesia • Paralysis
thrombosis vs embolus acute limb ischaemia
embolus more acute and sudden, more profound, but contralateral pulses present
need embolectomy and warfarin
for thrombosis they needthrombolysis and bypass surgery
investigating acute limb ischaemia
• Blood § FBC, U+E, INR, G+S § CK • ECG • Imaging § CXR § Duplex doppler § CT angio
management acute limb ischaemia
In an acutely ischaemic limb discuss immediately ¯c a
senior as time is crucial.
• NBM
• Rehydration: IV fluids
• Analgesia: morphine + metoclopramide
• Abx: e.g. co-amoxiclav if signs of infection
• Unfractionated heparin IVI: prevent extension
• Complete occlusion?
§ Yes: urgent surgery: embolectomy or bypass
§ No: angiogram + observe for deterioration
management of embolic acute limb ischameia
Embolus Mx 1. Embolectomy § Under regional anaesthesia or GA § Wire fed through embolus § Fogarty catheter fed over the top § Balloon inflated and catheter withdrawn, removing the embolism. § Adequacy confirmed by on-table angiography 2. Thrombolysis § Consider if embolectomy unsuccessful § E.g. local injection of TPA 3. Other options § Emergency reconstruction § Amputation Post-embolectomy • Anticoagulate: heparin IVI → warfarin • ID embolic source: ECG, echo, US aorta, fem and pop • Complications § Reperfusion injury - Local swelling → compartment syndrome - Acidosis and arrhythmia 2O to ↑K - ARDS - GI oedema → end
