Vascular Surgery Flashcards
(176 cards)
1
Q
How is ABPI calculated
A
Foot artery occlusion pressure / brachial systolic pressure
2
Q
ABPI >1.1 indicates
A
Calcified or incompressible vessels e.g. diabetes and renal failure
3
Q
ABPI 0.7-0.9 indicates
A
Mild ischaemia
4
Q
ABPI 0.4-0.7 indicates
A
Moderate ischaemia
5
Q
ABPI <0.4 indicates
A
Critical ischaemia
6
Q
What is the most accurate investigation for imaging the arterial system
A
Intra-arterial digital subtraction angiography (IADSA)
7
Q
What is the investigation of choice for imaging the lymphatic system
A
Lymphoscintigraphy
8
Q
How is lymphoscintigraphy performed
A
Radiolabelled colloid is injected into the webspace between the 2nd and 3rd toes and images obtained with a gamma camera
9
Q
What are the 3 histological layers of an artery
A
- Tunica intima
- Tunica media
- Tunica adventitia
10
Q
What are the 2 types of artery
A
- Elastic conducting arteries
2. Muscular distributing arteries
11
Q
Describe the tunica intima
A
- Innermost layer
- Single layer of endothelial cells orientated in the direction of flow
12
Q
Describe the tunica media
A
- Middle layer
- Composed of elastin and collagen fibres with vascular smooth muscle cells
13
Q
Describe the tunica adventitia
A
- Outermost layer
- Connective tissue
14
Q
What are the histological differences between the thoracic and abdominal aorta
A
Thoracic aorta has >30% elastin compared to <20% in the abdominal section
15
Q
What crosses the abdominal aorta anteriorly
A
- Splenic vein
- Body of pancreas
- 3rd part of duodenum
- Left renal vein
16
Q
What lies immediately to the right of the abdominal aorta
A
- IVC
- Right ureter
- Azygous vein
17
Q
What lies immediately to the left of the abdominal aorta
A
- Left sympathetic trunk
- Left ureter
18
Q
Define an aneurysm
A
Pathological dilatation of an artery to >1.5x its normal diameter
19
Q
What is the diameter of the aorta
A
2cm
20
Q
Define a true aneurysm
A
Dilatation of an artery involving all layers of the arterial wall
21
Q
Define a false aneurysm
A
Pulsatile, expansile swelling due to a defect in an arterial wall, with blood outside of the lumen, surrounded by a capsule of fibrous tissue or compressed surrounding tissue
22
Q
List the causes of aneurysms
A
- Degenerative (atherosclerotic) - MOST common
- Inflammatory
- Congenital (Berry aneurysm)
- Mycotic (bacterial, IE)
- Infective
23
Q
Where is the most common site of atherosclerotic AAA
A
Infrarenal
24
Q
Mortality rate for elective AAA repair
A
5%
25
In whom is elective AAA repair offered
Those with a AAA >5.5cm
26
What percentage of AAAs involve the iliac arteries
30%
27
What percentage of AAAs are asymptomatic
75%
28
Where does a AAA typically rupture and what does this cause
- Posterior wall
| - Retroperitoneal haematoma (bruising of the flanks/scrotum
29
Who is screened for AAA in the UK
65 year-old men
30
What histological changes are seen in AAAs of those with Marfan's
Cystic medial necrosis
31
How much blood should be cross-matched for ruptured AAA repair
10 units
32
What type of AAA repair is preferred if there is iliac involvement
- Open
| - Trouser Y-graft
33
List the immediate complications of AAA repair
- Primary Haemorrhage
| - Distal embolisation (ischaemic leg, trash foot)
34
List the early complications of AAA repair
- Haemorrhage (reactionary, secondary)
- MI
- Renal failure (esp if proximal clamp above renal vessels)
- Multi-organ failure/DIC/ARDS
- Colonic ischaemia
- Pneumonia
- Stroke
- DVT/PE
- Paraparesis due to spinal ischaemia
35
How much heparin is to be used prior to cross-clamping of the aorta
3000 units
36
What bacteria cause myoctic aneurysms
- Staph aureus
- Salmonella
- Streptococcus
37
List the late complications of AAA repair
- Late graft infection
- Aortoenteric fistula
- Anastomotic aneurysm
38
What are the requirements of conventional EVAR
Aneurysm needs to have a proximal neck of at least 5mm above the aneurysm and below the renal arteries
39
What type of endovascular graft can be used in those aneurysms not suited for conventional EVAR
Fenestrated EVAR (very expensive)
40
What are the follow-up implications for EVAR
Long-term due to high risk of late complications e.g. endoleak
41
Describe type 1 endoleaks
Leak from stent-graft attachment site
42
Describe type 2 endoleaks
Leak due to retrograde flow through visceral or lumbar arteries into aneurysm sac (most common type)
43
Describe type 3 endoleaks
Due to structural failure of the stent-graft e.g due to holes
44
Describe type 4 endoleaks
Due to graft porosity and usually settles with time
45
Describe type 5 endoleaks
Aneurysm sac continues to expand with time, but no leak is identified (endotension)
46
What is the 2nd most common site of atherosclerotic aneurysm
Popliteal artery
47
How do popliteal aneurysms present
- Aneurysm thrombosis or distal emboli leading to limb ischaemia
- Rupture is rare
48
How are popliteal aneurysms treated
- Ligation and vein bypass graft, OR
| - Endovascular stent
49
What percentage of those with a popliteal aneurysm will also have a AAA
30%
50
What is the most common type of visceral artery aneurysm
Splenic artery aneurysm
51
What are the indications for surgery in popliteal aneurysm
- Symptomatic
- Limb ischaemia
- Asymptomatic with thrombus
52
List the branches of the external iliac artery
- Inferior epigastric artery
| - Deep circumflex iliac artery
53
List the branches of the femoral artery
- Superficial circumflex iliac artery
- Superficial epigastric
- Superficial and deep external pudendals
- Profunda femoris
54
Describe the course of profunda femoris
- Largest branch of the femoral artery
- Arises posteriorly/posterolaterally
- Descends medially to enter adductor compartment
- Gives of medial and lateral circumflex femoral, then 3 perforators
- Ends as 4th perforator
55
Outline the bounds of the popliteal fossa
- Lateral = biceps femoris above, lateral head of gastroc and plantaris below
- Medial = semimembranosus and semitendinosus above, medial head of gastroc below
- Floor = popliteal surface of femur, posterior ligament of knee, popliteus mucle
- Roof = superficial and deep fascia
56
What is the deepest structure of the popliteal fossa
Popliteal artery
57
What is the most superficial structure of the popliteal fossa
Tibial nerve
58
What flanks the dorsalis pedis artery in the foot
- Medial = EHL tendon
| - Lateral = EDL tendons
59
What does the posterior tibial artery divide into
Medial and lateral plantar arteries
60
What is the most common caused of PVD
Atherosclerosis with thrombosis
61
Outline the structure of an atherosclerotic plaque
- Superficial fibrous cap
- Intra-intimal area with accumulation of lipids, smooth muscle cells, foam cells
- Basal zone with lipid accumulation and tissue necrosis
62
What is thromboangitis obliterans also known as
Buerger's disease
63
What is the classic demographic of Buerger's disease
Progressive obliteration of distal arteries in young men who smoke heavily
64
How is Buerger's disease managed
- Smoking cessation
- Sympathectomy to relieve arterial spasm
- Antibiotics
- Foot care
- Analgesia
- Prostaglandins for acute ischaemia
65
List the symptoms of acute limb ischaemia
- Pain
- Pulseless
- Pallor
- Paraesthesia
- Paralysis
- Perishing cold
66
What is the time-frame for resolution of acute limb ischaemia
4-6 hours
67
Outline the principles of managing acute limb ischaemia
1. Resuscitation
2. Immediate anticoagulation (5000 units heparin IV)
3. Analgesia
4. Restore arterial continuity
5. Identify and correct any underlying source of embolus
68
What is the investigation of choice in acute limb ischaemia if diagnosis in doubt
Arteriography
69
Describe the clinical appearance of a limb with <6 hours ischaemia
White
70
Describe the clinical appearance of a limb with 6-12 hours ischaemia
Mottled limb with blanching on pressure
71
Describe the clinical appearance of a limb with 12-24 hours of ischaemia
Fixed mottling
72
What is the preferred treatment for acute-on-chronic limb ischaemia
Thrombolysis
73
What are the contraindications to thrombolysis in acute limb ischaemia
- Extreme old age
- Recent surgery (2 weeks)
- Recent CVA (2 months)
- Peptic ulceration
- Bleeding tendencies
74
How should a white leg with sensorimotor deficit be managed
Surgery and embolectomy
75
How should a dusky leg with mild anaesthesia be managed
Angiography
76
How should a leg with fixed mottling be managed
Primary amputation
77
In those with acute limb ischaemia, when should fasciotomy be considered
If the time between onset and surgery exceeds 6 hours
78
What are the systemic effects of reperfusion injury
- Rhabdomyolysis
- Renal failure
- ARDS
- Myocardial dysfunction
- Clotting disorders
79
What are the early signs and symptoms of compartment syndrome
- Pain out of proportion to the condition/injury
- Pain on passive stretch
- Absent distal pulse
80
What are the late signs and symptoms of compartment syndrome
- Paralysis
- Weakness and tenderness
- Pale, cold limb
- Sensory loss
81
What incision is used for femoral embolectomy
Longitudinal incision in the groin below the inguinal ligament and over femoral artery
82
What incision is used for brachial embolectomy
Transverse incision below the skin crease at the elbow
83
What measures should be taken following surgery for acute limb ischaemia
- Check angiogram on table and prior to closure
| - Systemic heparinisation should follow surgery which should later be converted to Warfarin
84
What type of catheter is used for embolectomy
Fogarty catheter
85
What type of fasciotomy should be performed in lower leg compartment syndrome
Four-compartment fasciotomy
86
Describe Leriche syndrome
Distal aortic/Proximal iliac stenosis/occlusion causing:
- Buttock, thigh and calf claudication
- Erectile dysfunction
- Proximal muscle wasting
87
Outline the implications of Buerger's angles
- 50 degrees = severe ischaemia
| - 25 degrees = critical ischaemia
88
Outline the assessment of PVD
- Clinical examination
- ABPI
- Duplex arterial USS
- Angiography (only if intervention is planned)
89
What PVD lesions are amenable to angioplasty
- Short lesion
- Reasonable distal runoff
- Better for proximal disease
90
What can be used to supplement vein grafts that are not long enough in bypass surgery
Miller Cuff (made from PTFE)
91
Why are PTFE grafts unsuitable for distal disease
Undergo subintimal hyperplasia early which leads to occlusion and graft failure
92
What suture is used for vascular anastomosis
Fine non-absorbable monofilament (e.g. 5/0 prolene)
93
What type of arteriotomy is used in Fem-pop bypass
Longitudinal arteriotomy
94
When is fem-fem crossover used
Unilateral iliac occlusive disease not amenable to angioplasty or stenting
95
When is axillo-bifemoral grafting used
Aortic or bilateral iliac occlusion not amenable to angioplasty or stenting, in the presence of a hostile abdomen, or in a patient not fit for major abdominal surgery
96
When is aorto-bifemoral grafting used
Occlusive or stenotic aorto-iliac disease not amenable to stenting or angioplasty
97
What is the most likely cause of mid-term (1 year) graft failure
Neointimal hyperplasia causing stenosis of the graft
98
What is the most likely cause of late graft failure
Atheromatous disease progression
99
What graft is typically used for PVD
Long Saphenous vein used in reverse
100
How much bone should ideally be conserved in BKA
15cm
101
What are the indications for amputation (3 D's)
- Dead - non viable
- Deadly - tumour, severe infection
- Damn useless - pain, neurological damage
102
Describe a Gritti-Stokes amputation
- Supracondylar amputation preserving the patella
| - Double amputees
103
What type of flaps are used in above knee amputation
Anterior and posterior semicircular skin flaps
104
What type of flaps are used in below-knee amputations
1. Burgess flap - long posterior flap using posterior calf muscles to cover the bone ends 15cm below the tibial tuberosity
2. Skew Flap (MOST POPULAR)
105
When is a trans-metatarsal amputation indicated
Diabetic gangrene of the forefoot
106
What is the general rule for flap length:diameter ratio in amputation
1.5x diameter
107
What type of prosthesis can aide early mobilisation in amputation
POMAID
108
Describe the appearance of a neuropathic ulcer
- Punched-out lesion
| - Surrounded by a ridge of hard calloused skin
109
Define a Carcot's joint
Painless, disorganised joint due to decreased pain sensation and proprioception
110
What proportion of strokes are caused by carotid artery disease
15%
111
Describe stroke presentation of the carotid territory
- Contralateral hemiparesis
| - Dysphasia if dominant hemisphere
112
Describe stroke presentation of the vertebral hemisphere
- Vertigo
- Diplopia
- Blurred vision
- LOC
- Facial involvement
- Cerebellar signs
113
Who should be offered elective carotid endarterectomy
Patients with ipsilateral stenosis >70% that have caused symptoms in the previous 6 months
114
What is the GOLD standard assessment tool for carotid stenosis
Duplex doppler USS
115
What incision is used for carotid endarterectomy
Longitudinal incision at the anterior border of SCM
116
What nerves are at risk of damage in carotid endarterectomy
- Marginal mandibular
- Superior laryngeal
- Hypoglossal
- Great auricular
117
Histology of carotid body tumours
Paraganglionic cells of neural crest origin
118
Characteristic signs of carotid body tumours
- Mass adjacent to hyoid
- Smooth, compressible, pulsatile
- Red-brown appearance
119
What causes subclavian steal syndrome
Stenosis of the subclavian artery, proximal to the origin of the vertebral artery
120
What is the physiological result of subclavian steal syndrome
Any increase in the demand for blood to the arm causes reverse flow of blood from the cerebral circulation, through the vertebral artery, to supply the subclavian post-stenosis
121
What are the symptoms of subclavian steal syndrome
- Dizziness
- LOC
- Ataxia
- Visual loss
122
Explain the likely distribution of upper limb emboli
- 50% lodge in the brachial artery
| - 30% lodge in the axillary artery
123
What are the sources of upper limb emboli
- Left atrium from AF
| - Mural thrombus
124
Outline the management of upper limb emboli
- IV heparin
- Angiography/duplex
- Brachial embolectomy under GA
125
Describe the 3 clinical phases of Raynaud's syndrome
1. Digital blanching due to arterial spasm (white)
2. Cyanosis/pain due to stagnant anoxia (blue)
3. Reactive hyperaemia due to accumulation of vasoactive metabolites (red)
126
Drugs used to treat idiopathic Raynaud's syndrome
- Nifedipine
| - Prostacyclin
127
Where are the most common sites of hyperhidrosis
- Palms
- Axilla
- Feet
128
List the causes of secondary hyperhidrosis
- Hyperthyroidism
- Phaeochromocytoma
- Hypothalamic tumours
129
List the non-surgical interventions for hyperhidrosis
- Topical ammonium chloride
- Iontophoresis (elective current to incapacitate sweat glands)
- Botox (decreases sympathetic activity)
130
How is palmar hyperhidrosis treated surgically
- Laparoscope inserted into the pleural space via the axilla
- 2nd and 3rd thoracic ganglia are removed
131
Why is the first thoracic ganglia not removed in sympathectomy
Will cause Horner's syndrome
132
What is the best treatment for axillary hyperhidrosis
Botox
133
How is plantar hyperhidrosis treated
Chemical lumbar sympathectomy
134
What must be divided to perform a thoracic sympathectomy
Parietal pleura
135
Define thoracic outlet syndrome
Compression of the subclavian branches of the brachial plexus as they pass from the thorax into the arm
136
List the causes of thoracic outlet syndrome
- Cervical rib
- Abnormal muscle insertions or muscle hypertrophy
- Fibrous band
- Callus from old clavicular fracture
- Neck trauma
- Malignancy
137
What test may precipitate symptoms of thoracic outlet obstruction
Roos' test = abduction and external rotation of the arm may precipitate symptoms
138
How may thoracic outlet syndrome be surgically corrected
Decompression:
- Resection of 1st part of 1st rib
- Divide anterior scalene muscle
139
Where is upper limb venous occlusion likely to occur
- Axillary vein
| - Subclavian vein
140
What is the investigation of choice for diagnosing axillary vein thrombosis
Duplex scan
141
What is the best treatment for axillary vein thrombosis
Local catheter directed TPA
142
Describe cervical rib
Elongation of the 7th cervical vertebrae transverse process
143
List the causes of congenital AV fistulas
- Cirsoid
- Parkes-Weber syndrome
- Klippel-Trenaunay syndrome
144
Describe a Cirsoid aneurysm
Localised arteriovenous fistula typically occurring in the scalp
145
Describe Parkes-Weber Syndrome
Congenital condition of multiple AV malformation associated with increased limb size, dilated superficial veins with ulceration, and high-output cardiac failure
146
Describe Klippel-Trenaunay syndrome
Combination of:
- Port-wine staining
- Varicose veins
- Hypertrophy of bony and soft tissues
- Improperly developed lymphatic system
147
List the deep veins of the leg
- Posterior tibial
- Anterior tibial
- Peroneal
- Soleal
- Gastrocnemius
148
List the deep veins of the thigh
- Popliteal
- Superficial femoral vein
- Deep (profunda) femoral vein
- Iliac
149
List the superficial veins of the lower limb
- Long saphenous
| - Short saphenous
150
Where does the long saphenous vein communicate with the deep venous system of the leg
- Saphenofemoral junction
- Mid-thigh perforator
- Medial calf perforators (3 or 4)
151
Where does the short saphenous vein join the deep circulation
Enters popliteal vein after piercing deep fascia
152
Where does the short saphenous vein communicate with the deep venous system
- Popliteal vein
- Gastrocnemius communicating veins
- Lateral calf communicating veins
153
Most common site of varicose veins
Long saphenous system
154
Describe primary varicose veins
Form due to gravitational venous pooling and vein wall laxity causing venous dilatation and valve leakage
155
Describe secondary varicose veins
Caused by obstruction of deep venous outflow (e.g. DVT, pelvis malignancy) resulting in blood being forced to the superficial system
156
How may sites of venous incompetence be formally assessed
USS doppler
157
Define Saphena Varix
Reducible swelling in the groin due to a dilated varix at the saphenofemoral junction
158
List the indications for surgery to treat varicose veins
- Cosmetic (majority)
- Lipodermatosclerosis causing venous ulceration
- Recurrent superficial thrombophlebitis
- Bleeding from ruptured varix
159
List the surgical options for symptomatic uncomplicated varicose veins
- Endothermal ablation
- Foam sclerotherapy
- Saphenofemoral/popliteal disconnection
- Stripping and avulsions
160
What structures are at risk during long saphenous vein surgery
Saphenous nerve (sensory loss)
161
What structures are at risk with short saphenous vein surgery
- Sural nerve (sensory loss)
| - Common peroneal nerve (foot drop)
162
Outline the two theories of venous ulcer formation
1. Leucocyte trapping theory
| 2. Fibrin cuff theory
163
How are chronic venous ulcers managed
Class 2-3 compression stockings (ensure no arterial disease)
164
Describe 4-layer compression bandaging
1. Cotton wool
2. Crepe
3. Elastic bandage
4. Cohesive bandage
165
What parasite is responsible for filariasis
Wuchereria bancrofti (usually transmitted by mosquitos)
166
What does lymphoedema involve
- Accumulation of protein-rich fluid
- Subdermal fibrosis
- Dermal thickening
167
Where is fluid confined to in lymphoedema
Epifascial space (skin and subcutaneous tissues)
168
Cause of primary lymphoedema in those aged <1
Milroy's disease (congenital)
169
Cause of primary lymphoedema in those aged 1-35
Meige's disease
170
Cause of primary lymphoedema in those >35
Tarda
171
List the indications for surgery in lymphoedema
- Marked disability or deformity from limb swelling
- Lymphoedema caused by proximal lymphatic obstruction with patent distal lymphatics suitable for a lymphatic drainage procedure
- Lymphocutaneous fistulae and megalymphatics
172
How can the diagnosis of lymphoedema be confirmed
Lymphoscintigraphy
173
How can detailed anatomy fo the lymphatic system be detailed prior to lymphatic reconstruction
Lymphangiography
174
What procedure is indicated for those with proximal lymphatic obstruction and normal distal lymphatics
Lymphovenous anastamosis
175
Which procedure is indicated in lymphoedema with good overlying skin
Homan's operation
176
Which procedure is indicated in lymphoedema with poor overlying skin
Charles operation
