Vascular Surgery Flashcards
Define Acute mesenteric ischaemia
Sudden decrease in blood supply to the bowel resulting in bowel ischaemia and rapid gangrene
List the common causes of acute mesenteric ischaemia
AAA Embolism Atherosclerosis (thrombus-in-situ) Shock Coagulopathy Malignancy Inflammatory disorders
Describe clinical features of mesenteric ischaemia
- Generalised abdominal pain, out of proportion to other clinical findings
- Nausea and vomiting
- History indicating potential embolic sources
- Presentation similar to bowel perforation (late stage)
What initial lab investigations would you order when considering mesenteric ischaemia?
- ABG - assess degree of acidosis and serum lactate
- Routine bloods: FBCs, U+Es, Clotting screen, LFTs, G+S
- Amylase (will be raised)
What is the diagnostic test for acute mesenteric ischaemia?
CT angiography with IV contrast - Triple phase scan (thin slices taken in arterial phase)
What will a CT scan of arterial bowel ischaemia show?
Oedematous bowel
Loss of bowel wall enhancement
Pneumatosis intestinalis
What initial management is needed in acute mesenteric ischaemia?
Urgent resuscitation - IV fluids, catheter insertion, fluid balance chart
Broad spectrum antibiotics prescribed
Early ITU admission if significant acidosis
What is the definitive management for ischaemic bowel?
- Excision of necrotic or non viable bowel
- Revascularisation of bowel - removal of thrombus or embolism via angioplasty
What are the main complications of acute mesenteric ischaemia?
Bowel necrosis
Bowel perforation
What is the mortality rate for acute mesenteric ischaemia?
50-80% (even with treatment)
Define chronic mesenteric ischaemia
Lack of blood supply to the bowel which gradually deteriorates over time as a result of atherosclerosis in the CT, SMA or IMA
Why do symptoms of chronic mesenteric ischaemia tend to occur after eating?
Increased demand of blood supply causes a transient ischaemia of the bowel
What is the pathophysiology of chronic mesenteric ischaemia?
Gradual build up of atherosclerotic plaques within the lumen of at least two of the CT, SMA or IMA causing reduced blood flow and so ischaemia
What are the main risk factors for chronic mesenteric ischaemia?
Smoking
Hypertension
Diabetes mellitus
Hypercholesterolaemia
Describe the classical clinical features of chronic mesenteric ischaemia
Post prandial pain (10mins-4hrs post eating) Weight loss Concurrent vascular co morbidities Change in bowel habit N+V
What is the gold standard diagnostic test for chronic mesenteric ischaemia?
CT angiography
What are possible differentials for chronic non specific abdominal pain?
Chronic pancreatitis
Gallstone pathology
Peptic ulcer disease
Upper GI malignancy
What medical management is indicated for chronic mesenteric ischaemia?
Antiplatelet agent
Statin
Lifestyle advice: weight loss, increasing exercise, smoking cessation
What surgical intervention may be indicated in chronic mesenteric ischaemia?
Endovascular - mesenteric angioplasty with stenting
Open - endarterectomy or bypass
When would surgical intervention be considered in chronic mesenteric ischaemia?
Severe disease
Progressive disease
Presence of debilitating symptoms (eg weight loss or malabsorption)
What are the main complications of chronic mesenteric ischaemia?
Bowel infarction
Malabsorption
Concurrent CVS disease
What is an aneurysm?
A persistent, abnormal dilation of an artery (>1.5x its normal diameter)
Define an aneurysm
Persistent, abnormal dilation of an artery above 1.5x its normal diameter
What possible causes are there of aneurysms?
Trauma
Infection
CT disease
Inflammatory disease (eg. Takayasu’s aortitis)
What is the gold standard imaging for peripheral and visceral aneurysms?
CT angiography
What is an alternative investigation for aneurysms to reduce kidney damage?
MR angiography
What imaging modality can be used for detection and follow up of aneurysms?
US duplex scan
What are the two most common peripheral artery aneurysms?
Popliteal artery
Femoral artery
How may a popliteal artery aneurysm present?
Acute limb ischaemia
Intermittent claudication
Incidental finding
What are the main DDx for swelling in the popliteal fossa?
Politeal aneurysm
Bakers cyst
Lymphadenopathy
When should an asymptomatic popliteal aneurysm be treated?
If it is greater than 2cm
Why should all symptomatic popliteal aneurysms be treated?
High risk of embolisation
What surgical options are there for popliteal aneurysms?
- Endovascular repair (stent insertion)
- Open repair (ligation of aneurysm or resection with a bypass graft)
What are the two major causes for development of a femoral artery aneurysm?
- Percutaneous vascular interventions
- IVDU using the groin
What will a patient with femoral aneurysms normally present with?
Varying degrees of claudication or acute limb ischaemia
* Often may have no symptoms beside swelling in the groin
What causes the signs and symptoms of femoral aneurysms?
Thrombosis, rupture or embolisation
What additional features may be seen in an IVDU patient with a femoral aneurysm?
Concurrent infection
What is the main treatment for a femoral artery aneurysm?
Open surgical repair
Which visceral arteries are most commonly affected by aneurysm formation?
- Splenic artery
- Hepatic artery
- Renal artery
How may a splenic artery aneurysm present?
Vague epigastric or LUQ pain
Rupture –> severe abdo pain and haemodynamic compromise
What is first line management for a splenic artery aneurysm?
Endovascular repair
What are the common causes of a hepatic artery aneurysm?
Percutaneous instrumentation
Trauma
Degenerative disease
Post liver transplant
What may a symptomatic case of hepatic artery aneurysms present like?
Vague RUQ or epigastric pain
Jaundice (if biliary obstruction)
What is first line management for hepatic artery aneurysms?
Endovascular repair –> best with embolisation or stent gradts
How may a patient with a symptomatic renal artery aneurysm present?
Haematuria
Resistent hypertension
Loin pain
What is the mainstay of treatment for a patient with a renal artery aneurysm?
Endovascular repair:
- Hilar –> with coils and self expanding stents
- Main artery –> stent
What are some of the risk factors for splenic artery aneurysms?
- Female
- Portal hypertension
- Pancreatitis
What is chronic limb ischaemia typically caused by?
Atherosclerosis (typically in the lower limbs)
What are the risk factors for chronic limb ischaemia?
Smoking Diabetes mellitus Hypertension Hyperlipidaemia Increasing age Family history Obesity + physical inactivity
Describe the fontaine classification of chronic leg ischamia
1 - Asymptomatic
2 - Intermittent claudication
3 - Ischaemic rest apin
4 - Ulceration or gangrene (or both)
Describe Buerger’s test briefly
Lie the patient supine and raise their legs until they go pale - note the angle at which this happens (= Buerger’s angle)
Then lower the legs until the colour returns/goes hyperaemic
What angle in Buerger’s test will indicate severe chronic limb ischaemia?
Angle of less than 20 degrees
What is Leriche syndrome?
Form of peripheral arterial disease affecting the aortic bifurcation – presents with buttock or thigh pain +/- erectile dysfunction
What three definitions are there for critical limb ischaemia?
- Ischaemic rest pain for >2 weeks, requiring opioids
- Presence of ischaemic lesions (or gangrene attributable to PVD)
- ABPI >0.5
What clinical features are seen on examination of a limb with critical ischaemia?
Pale, cold and pulseless limb
Hair loss, skin changes (eg. atrophic, ulceration, gangrene), thickened nails
What are the two major differentials for limb ischaemia?
Spinal stenosis ("neurogenic claudication") Acute limb ischaemia
How may spinal stenosis be differentiated from chronic limb ischaemia?
Pain in the back radiating down lateral aspect of leg
Symptoms worse on initial movement and relieved by sitting
How is the ABPI used to quantify the severity of chronic limb ischaemia?
Normal = >0.9 Mild = 0.8-0.9 Moderate = 0.5-0.8 Severe = <0.5
What may cause a falsely elevated ABPI?
Calcification and hardening of arteries
>1.2
What initial investigation should be used for critical limb ischaemia?
Doppler ultrasound
What additional assessment should be done to assess for risk factors in chronic limb ischaemia?
Cardiovascular risk assessment
- BP
- Blood glucose
- Lipid profile
- ECG
What should be checked in a patient <50yrs with chronic limb ischaemia?
Thrombophillia screen Homocysteine levels (higher is associated with CVS events)
What is the management for CVS risk factors in chronic limb ischaemia?
- Lifestyle advice
- Statin therapy
- Antiplatelet therapy
- Optimise diabetic control
What is first line management for intermittent claudication?
Enrolment into a local supervised exercise programme
When should surgical intervention be offered to patients with chronic limb ischaemia?
- If risk factor modification has been discussed
- Supervised exercise has failed to improve symptoms
What are the two main surgical interventions used for chronic limb ischaemia?
- Angioplasty +/- stenting
- Bypass grafting (often for diffuse disease or younger)
- Combination (eg. surgery to clean lesion to allow access for angioplasty to another region)
When should amputation be considered in chronic limb ischaemia?
Unsuitable for revascularisation with ischaemia causing incurable symptoms or gangrene leading to sepsis
What complications are there of chronic limb ischaemia?
- Sepsis (secondary to infected gangrene)
- Acute on chronic ischaemia
- Amputation
- Reduced mobility
- Reduced QoL
What is the 5 year mortality rate of those diagnosed with chronic limb ischaemia?
~50%
Define acute limb ischaemia
Sudden decrease in limb perfusion that threatens the viability of the limb
What are the three main classifications of cause for acute limb ischaemia?
- Thrombosis in situ
- Embolisation
- Trauma
What are the 6 P’s of acute limb ischaemia?
Pain Pallor Pulselessness Parasthesia Perishingly cold Paralysis
How can you identify an embolic occlusion as the cause of acute limb ischaemia?
Normal and pulsatile contralateral limb
After what time period is presentation with acute limb ischaemia likely to result in paralysis?
> 6hrs post symptoms onset
If both arterial and venous doppler are audible in acute limb ischaemia, what category is it?
I - Viable
What are the main DDx for acute limb ischaemia?
- Critical chronic limb ischaemia
- Acute DVT
- Spinal cord or peripheral nerve compression
Why is a serum lactate indicated in acute limb ischaemia?
Assess level of ischaemia
What initial investigation is used for acute limb ischaemia?
Doppler USS of both limbs
When should a CT angiogram be done in acute limb ischaemia?
If the limb is considered salvageable - identifies anatomical location of occlusion
What is the immediate management for a patient with acute limb ischaemia?
High flow o2 + adequate IV access
**Therapeutic dose of heparin or bolus dose then heparin infusion
How are Rutherford stage 2a and 2b differentiated in acute limb ischaemia?
2a = minimal sensory loss 2b = sensory loss i more than toes + rest pain
What is conservative management for acute limb ischaemia?
Prolonged course of heparin (only for Rutherford 1 and 2a)
What surgical intervention is used for embolic acute limb ischaemia?
- Embolectomy via a Fogarty catheter
- Local intra-arterial thrombolysis
- Bypass surgery
What surgical intervention is used for thrombotic acute limb ischaemia?
- Local intra-arterial thrombolysis
- Angioplasty
- Bypass surgery
What will irreversible limb ischaemia look like?
Mottled, non blanching limb with hard, woody muscles
What long term management is needed for acute limb ischaemia?
- Reduction of CVS mortality risk
- Antiplatelets
- ?Anticoagulation
What is the mortality rate of acute limb ischaemia?
~20%
What are the complications of acute limb ischaemia?
- Reperfusion injury
- Compartment syndrome
- Hyperkalaemia
- Acidosis
- AKI (from myoglobin release)
What is the gold standard investigation for acute limb ischaemia?
CT angiography
Define varicose veins
Tortuous dilated segments of veins associated with valvular incompetence, permitting blood flow from the deep venous system into the superficial
What is the result of blood flow from the deep venous system into the superficial venous system?
Venous hypertension and dilation of superficial veins
List the common secondary causes of varicose veins
DVT
Pelvic masses (eg. Pregnancy, uterine fibroids, ovarian masses)
AV malformations
List the four major risk factors for the development of varicose veins
- Prolonged standing
- Obesity
- Pregnancy
- Family history
What will patients with varicose veins usually present with?
Cosmetic issues (eg visible veins or discolouration)
Pain
Aching
Swelling (often worse on standing)
What is seen on examination of a patient with varicose veins?
Varicosities along course of great and/or short saphenous veins
Features of venous insufficiency
What are some features of venous insufficiency?
Oedema Varicose eczema Thrombophlebitis Ulcers (often over medial maleolus) Haemosiderin skin staining Lipodermatosclerosis Atrophie blanche
What is a saphena varix?
Dilation of the saphenous vein at the saphenofemoral junction
Displays a cough impulse —> often mistaken for a femoral hernia
What system is used for classification of varicose veins?
CEAP
- Clinical features
- aEtiology
- Anatomical
- Pathophysiology
What is the gold standard investigation for varicose veins?
Duplex ultrasound
Name some non-invasive treatments for varicose veins
Patient education - avoid prolonged standing, weight loss + exercise
Compression stockings
Four layer bandaging (for venous ulceration)
What are the criteria for surgical referral with varicose veins?
- Symptomatic primary or recurrent varicose veins
- Lower limb skin changes from venous insufficiency
- Superficial vein thrombosis with suspected venous incompetence
- Venous leg ulcer
What are the main surgical treatment options for varicose veins?
- Vein ligation, stripping and allusion
- Foam scleropathy
- Thermal ablation
What are the main complications of varicose veins?
Haemorrhage Thrombophlebitis DVT Disease recurrence Nerve damage
What does the term chronic venous insufficiency encompass?
DVT
Valvular insufficiency
Varicose veins
What is deep venous insufficiency characterised by?
Valvular reflux
Venous hypertension
Obstruction
What is meant by primary causes of deep venous insufficiency?
Underlying defect in the vein wall or valvular component eg. Congenital defects + CT disorders
What is meant by secondary causes of deep venous insufficiency?
Defects occur secondary to damage
Eg. Post-thrombotic disease, post-phlebitis disease, venous outflow obstruction + trauma
List the main risk factors for deep venous insufficiency
Increasing age Female Pregnancy Previous DVT or phlebitis Obesity Smoking
Describe a classical presentation of deep venous insufficiency
Chronically swollen lower limbs
Aching, pruritic and painful
Venous claudication - bursting pain and tightness on walking resolving on leg elevation
What signs may be seen on a patient with deep venous insufficiency?
Varicose eczema Thrombophlebitis Haemosiderin skin staining Lipodermatosclerosis Atrophie Blanche \+ possible dependent oedema and venous ulcers
What are the symptoms of post thrombotic syndrome?
- Heaviness
- Cramping
- Pain
- Pruritis
- Paraesthesia
- Pretibial oedema
- Skin induration
- Hyperpigmentation
- Venous entasis
- Ulceration
What scale is used to monitor the degree of post thrombotic syndrome?
Villalta scale - assesses progression with treatment
What is the primary investigation for deep venous insufficiency? What is it looking for?
Doppler USS
Extent of venous reflux, sites of stenosis and presence of DVT or varicose veins
What investigation should be done before compression therapy is initiated?
- Documentation of foot pulses
- ABPI
What conservative management is there for deep venous insufficiency?
- Compression stockings
- Analgesic control
- 4 layer bandage for venous ulcer
When may venous stunting be used for deep venous insufficiency?
Severe post thrombotic syndrome with occluded iliac veins
What are common complications of deep venous insufficiency?
- Swelling
- Recurrent cellulitis
- Chronic pain
- Ulceration
What are the serious complications of deep venous insufficiency?
- DVT
- Secondary lymphoedema
- Varicose veins
What is subclavian steal syndrome?
Neurological deficits occurring when there is increased blood supply to the affected arm
—> secondary to a proximal stenosing lesion or occlusion in the subclavian artery
How is the blood supply redirected in subclavian steal syndrome?
Blood is drawn from collateral circulation causing a reversed blood flow in the ipsilateral vertebral artery
What are the common causes of subclavian steal syndrome?
- Atherosclerosis **
- Vasculitis
- Thoracic outlet syndrome
- Complications post aortic coarctation repair
What are the main clinical features of subclavian steal syndrome?
- Arm claudication
- Cerebral symptoms eg. Vertigo, diplopia, dysphagia, visual loss, syncope
What initial investigation is usually used for subclavian steal syndrome? What will it show?
Duplex USS
Shows retrograde flow in the affected vertebral artery during exercise
Why is a CXR done in subclavian steal syndrome?
Assess for any external compression on the subclavian artery
What is the definitive investigation for subclavian steal syndrome?
CT angiography (or MR angiography)
Describe the three grades of subclavian steal syndrome
Pre-subclavian steal: demonstrating purely a reduced anterograde vertebral flow
Intermittent alternating flow: antegrade flow in diastolic phase, retrograde flow in systolic
Advanced disease: permanent retrograde flow
What is the management for subclavian steal syndrome?
- Antiplatelet and statin therapy
- Address modifiable CVS risk factors
- Surgical: endovascular or bypass
When is bypass surgery indicated for subclavian steal syndrome?
Longer or distal occlusions
What does ‘carotid artery disease’ refer to?
Build up of atherosclerotic plaque in one or both of common and internal carotid arteries
How is carotid artery disease classified?
Radiologically based on the degree of stenosis
How will symptomatic carotid artery disease present?
Focal neurological deficit
- TIA
- Stroke
What are the main vascular DDx of carotid artery disease?
- Carotid dissection
- Thrombotic occlusion of carotid artery
- Fibromuscular dysplasia
- Vasculitis
What is fibromuscular dysplasia?
Hypertrophy of vessel wall causing stenosis of the artery
What initial investigations are indicated for any stroke patient?
- Urgent CT head
- Bloods: FBC, U&Es, Coag, Lipid profile, Glucose
- ECG
What is the role of CT angiography in carotid artery disease?
Gives percentage stenosis and characterises diseased portion of vessel for surgical intervention
What is indicated for ischaemic stroke prevention?
Carotid endarterectomy
What are the risks associated with carotid endarterectomy?
- Stroke
- Nerve damage (CN 9, 10, 12)
- MI
- Bleeding
- Infection
Define an aneurysm
Abnormal dilation of a blood vessel by >50% of its normal diameter
Define an abdominal aortic aneurysm
Dilation of the abdominal aorta >3cm
What possible causes are there for development of an AAA?
- Atherosclerosis
- Trauma
- Infection
- CT disorders eg. Marfan’s, Ehler’s Danlos, Loey Dietz
- Inflammatory disease eg. Takayasu’s aortitis
What are the main risk factors for AAA?
- Smoking
- Hypertension
- Hyperlipidaemia
- FHx
- Male
- increasing age
How may a AAA present?
- Incidental finding/on screening
- Abdominal pain
- Back/Loin pain
- Distal embolisation producing limb ischaemia
- Aortoenteric fistula
Briefly outline the National AAA screening programme
Offer an abdominal USS for all men aged 65
- 3-4.4cm –> Yearly screening
- 4.5-5.4cm –> Scan every 3 months
- > 5.5cm dilation –> consider for surgery
Give the main DDx for a symptomatic AAA
- Renal colic *
- Abdominal pathology eg diverticulitis, IBD, GI haemorrhage, appendicitis, ovarian torsion/rupture, splenic infarct
What investigation is done to follow up a diagnosis of a AAA on a USS?
CT scan with contrast
What lifestyle advice can be given to patients with a small/medium AAA?
- Smoking cessation
- Improve BP control
- Commence statin and aspirin therapy
- Weight loss
- Increase exercise
What indications are there for surgical intervention of a AAA?
- AAA >5.5cm
- AAA expanding at >1cm per year
- Symptomatic AAA in an otherwise fit patient
What are the main surgical options for AAA?
- Open repair
- Endovascular repair
Compare the outcomes of open and endovascular repair for a AAA
Similar long term outcomes at 2 years
Endovascular repair has improved short term outcomes - reduced hospital stay and 30 day mortality but higher rate of intervention + aneurysm rupture
What is involved in an open repair for a AAA?
Midline laparotomy or long transverse incision - clamp either end and remove the segment - then replace with a prosthetic graft
What does endovascular repair involve for a AAA?
Introduction of a graft via the femoral arteries + fixing a stent across the aneurysm
What is an endovascular leak?
Complication of endovascular repair - incomplete seal forms around the aneurysm resulting in blood leaking around the graft
What are the main complications of a AAA?
- Rupture
- Retroperitoneal leak
- Embolisation
- Aortoduodenal fistula
How can a AAA rupture present?
- Abdominal pain
- Back pain
- Syncope
- Vomiting
What is the classic triad for a ruptured AAA?
- Flank or Back Pain
- Hypotension
- Pulsatile abdominal mass
How is the BP controlled in a ruptured AAA?
Permissive hypotension - maintain at <100mmHg
— Raised BP can dislodge any clots and precipitate further bleeding
What is the management for a ruptured AAA?
A-E
- If unstable –> immediate transfer to theatre for open surgical repair
- If stable –> CT angiogram to determine if endovascular repair is suitable
Define an aortic dissection
Tear in the intimal layer of the aortic wall –> causes blood to flow between and so causing a split between the tunica intima and tunica media
What is the difference between the timescale for an acute and chronic aortic dissection?
Acute = diagnosed <14 days Chronic = diagnosed >14 days
How does an anterograde aortic dissection propagate?
Towards the iliac arteries
How does a retrograde aortic dissection propagate? What can this cause?
Towards the aortic valve –> valvular prolapse, bleeding into the pericardium + cardiac tamponade
What two classification systems can be used for an aortic dissection?
- DeBakey
- Stanford
Briefly describe the DeBakey classification for aortic dissections
Type 1 - originates in ascending aorta + propagates to at least the aortic arch
Type 2 - confined to ascending aorta
Type 3 - originates distal to subclavian artery in descending aorta
- 3a = extension distally to diaphragm
- 3b = extension beyond diaphragm to abdominal aorta
Briefly describe the Stanford classification of aortic dissection
Group A - DeBakey 1+2
Group B - DeBakey 3
What risk factors are there for aortic dissections?
- Hypertension
- Atherosclerotic disease
- Male gender
- CT disorder eg. Marfan’s or Ehler’s Danlos
- Bicuspid aortic valve
How does an aortic dissection classically present?
Tearing chest pain, radiating to the back
What clinical signs are commonly seen for an aortic dissection?
- Tachycardia
- Hypotension
- New aortic regurgitation murmur
- Signs of end organ hypoperfusion
What are the main DDx for an aortic dissection?
- MI
- PE
- Pericarditis
- MSK back pain
What first line imaging is there for an aortic dissection? Why?
CT angiogram - allows classification, establish anatomy and assists surgical planning
How is management of aortic dissection different by classification?
Stanford Type A - surgical
Stanford Type B - medical
What long term management is there for aortic dissections?
- Lifelong antihypertensive therapy
- Surveillance imagine (1, 3, + 12 months post discharge and then at 6-12 month intervals)
What surgical management is indicated for aortic dissections?
Removal of ascending aorta + replacement with synthetic graft
+ ensure additional branches are re-implanted into the graft
What medical management is given for aortic dissections?
Management of hypertension (rapidly lower systolic pressure, pulse pressure + pulse rate –> minimise stress of dissection + limit further propagation)
When is surgical intervention indicated in a type b aortic dissection?
Complications eg
- Rupture
- Visceral or limb ischaemia
- Refractory pain
- Uncontrollable hypertension
What are the main complications of an aortic dissection?
- Aortic rupture
- Aortic regurgitation
- MI (secondary to coronary artery dissection)
- Cardiac tamponade
- Stroke/paraplegia (secondary to cerebral/spinal artery involvement)