Vascular surgery

Question 1

Causes of acute arterial occlusion or insufficiency

Answer 1

Pro embolic states - Cardiac arrhythmias, endocarditis, aneurysms
Hyper coagulable states - Congenital clotting disorder e.g. antithrombin deficiency, protein C def or factor V Leiden, prothrombin or hyperhomocysteinemia. Acquired eg immobility, cancer, pregnancy, anti phospholipid syndrome, inflammatory disorders

Question 2

Presentation of Acute arterial occlusion or insufficiency

Answer 2

6 P
Pain, Pallor, parenthesis, Paralysis/reduced power (impending gangrene), Polar/poikilothermia (Cold), pulselessness.
Graded by sensory and motor defects
Grade 1: Viable, Non sensory or motor deficit = no immediate threat
Grade 2: Marginally threatened, Minimal sensory eg toes deficit, no motor = Salvaeable if promptly treated
Grade 3: Immediately threatened, More than toes sensory loss and mild to moderate motor loss = Salvageable if promptly revascularised
Grade 4: Irreversible , Profound sensory and motor loss egnumb and paralysis = major tissue loss, amputation, permanent nerve damage inevitable
Differentiate Embolus to thrombus
Embolus - acute, prominent loss of S and M, No Hx of claudication or atrophic changes and normal collaterals pulses.
Thrombus - Progressive or acute on chronic onset, Less profound S and M loss, may have Hx of claudication or atrophic changes. Contralateral limb pulse reduce or absent.

Question 3

Ix for acute arterial occlusion

Answer 3

Hx and Ex - if immediately threaten go to surgery
ABI
ECG and troponin - rule out MI or arrhythmia
FBC - leukocytosis, thrombocytosis, reduced PLT.
PR/INR - check pt anticoagulant therapy
Echo - source - wall motion abnormalities, thrombus, valvular disease, aortic Disection type A
CT - Underlying atherosclerosis, aneurysm,aortic dissection
Conventional catheter based angiography in OR or prelude to thrombocytosis

Question 4

Tx for Acute arterial occlusion

Answer 4

Heparin
Emergent revascularisation if impaired neurovascular status.
If not neurovascular impaired then work up including angiogram
Definitive Tx
- embolus - embolectomy
- Thrombus - Thrombectomy may need bypass graft or endovascular therapy
- If irreversible ischemia (no M Ro S, Absent V and A dopplers and rigor - amputation
Tx underlying cause
Post operative - Heparin and may need warfarin depending on underlying cause

Question 5

Cx of acute arterial occlusion

Answer 5

Compartment syndrome with prolonged ischemia - 4 compartment fasciotomy
Risk of arrhythmia and depth with reperfusion injury
Renal failure and multi organ failure due to toxic metabolites
12-15% mortality rate
5-40% morbidity rate - amputation.

Question 6

DDX for claudication

Answer 6

Vascular - atherosclerotic disease, Vasculitis eg Buerger’s disease, Diabetic neuropathy, Venous disease eg DVT or varicose veins, Popliteal entrapment syndrome eg baker’s cyst
Neurological - Neurospinal disease eg spinal stenosis, Reflex sympathetic dystrophy.
MSK - osteoarthritis, rheumatoid arthritis, CT disease, remote trauma

Question 7

How to differentiate vascular and neurogenic claudication

Answer 7

Vascular
Releived when stop walking, worse when walking uphill, pulses and ABIs reduced, Pain on cycling, no motor weakness after walking, and skin changes present.
Neurogenic
Improved on bending over or sitting, worsen when walking down hill, Pulses and ABI is normal, no pain on cycling, Motor weakness after walking, Skin changes absent.

Question 8

Commonest cause of Chronic artery occlusion

Answer 8

Atherosclerosis in lower limb

Question 9

Risk factors for Chronic artery occlusion

Answer 9

Major ones are smoking and DM

Minor - HTN, Hyperlipideamia, FMHx, Obesity, sedentary lifestyles, PMHX or FmHx CAD/CVD

Question 10

Signs and symptoms of chronic artery occlusion

Answer 10

Claudication - on exertion, relieved by rest and no postural changes necessary. Reproducible over same distance in same spot and received by same rest.
Critical if pain at rest, or night or tissue loss eg ulcers or gangrene.Pain on forefoot and improved by hanging foot off bed. ABI less than 0.40
Pulses may be absent, may have Bruins
Signs of poor perfusion - hair loss, hypertrophic nails, atrophic muscle, skin ulceration and infection, slow CRT, Prolonged pallor with elevation and rub or on dependency, venous trough get
Other signs of atherosclerosis - CVD, CAD, impotence, splanchnic ischemia

Question 11

Ix for chronic artery occlusion

Answer 11

Bloods - FBC, Fasting lipid, U and E, Coags,
ABI - less then 0.9 abnormal. Rest pain is at 0.3
CTA and MRA
Arteriography

Question 12

Tx for Chronic artery occlusion

Answer 12

Conservative - risk factor modification - stop smoking, sugar, BP, and lipid control, antiplt. Exercise. Foot care
Meds - Anti PLT, clostazol (cAMP phosphodiesterase)
Surgery
- Indicated if severe lifestyle impairment or critical ischemia
- Endovascular - stunting or angioplasty
- Endarterectomy - removal plaque and repair with patch
- Bypass graft sites -
- Chemical Sympathectomy - vasodilation
- Amputation - when not suitable for revascularisation or persistent serious infection/gangrene

Question 13

What is an Aortic dissection

Answer 13

Tear in aortic intima allowing blood to dissect into the media
Type A involves the ascending aorta
Type B only descending aorta
Acute less then 2 was

Question 14

Cause of aortic dissection

Answer 14

Most common - HTN causing degenerative and cystic changes to damage aortic media
Other
CT disease eg Marfan's or Ehler's
Caustic medial necrosis
Atherosclerosis
Congenital conditions eg coarctation
Infections eg syphilis
Trauma
Arteritis eg Takayasu's

Question 15

Who get aortic dissection

Answer 15

Males more then femal
African Americans more then Asians
50-65 yr old or 20-40 if CT disease

Question 16

Presentation of Aortic dissection

Answer 16

Sudden onset tearing chest pain that radiates to back
Hx of HTN, ischemia syndromes to to occulsions eg MI, Ischemic stroke, Horner syndrome, Mesenteric ischemia, AKI, Peripheral ischemia
Rupture into pleura - dyspnea or hemoptysis. Peritoneum - hypotension and shock. Or Pericardium - Cardiac tamponade
Syncope
Ex - asymmetric BP and pulses, new diastolic murmur caused by unseating of aortic valve cups in a type A dissection

Question 17

Ix in Aortic dissection

Answer 17

CXR - pleural cap, widened mediastinum, left pleural effusion
TEE - visualise aortic valve and thoracic aorta
ECG - LVH,may have Ischemic changes or pericarditis or heart block
CT - Gold standard - a orthography, MRI
Blood - Lactate (DDX Ischemic gut), Amylase (Pancreatitis), Troponin (MI)

Question 18

Tx aortic dissection

Answer 18

Meds - B Blocker - reduced BP and cardiac contracitlity
- Maintain sblood pressure 110 and HR under 60.
- ACEI and/or other vasodilator to control BP and HR
Surgery - Type A Cardiac surgery, Type B Vascular surgery.
- Surgical or endovascular.
Prognosis - 60% survival 5yr

Question 19

Define aortic aneurysm

Answer 19

Dilation 1.5 times that of normal
Risk of rupture increase once more then 4cm
True envolves all layers

Question 20

Cx of aortic aneurysm

Answer 20

Rupture,, thrombosis,embolism,erode and fistulize

Question 21

Most common type of aneurysm

Answer 21

Infra renal - aneurysm originages distal to the renal arteries

Question 22

Causes and risk factors of Aortic aneurysm

Answer 22

Degenerative eg atherosclerotic
Traumatic
Mycotic eg salmonella, staphylococcus - suprarenal aneurysm
CT disorder Marfan’s syndrome, Ehler’s Danlos syndrome
Vasculitis
Infections eg syphilis, fungal
Ascending thoracic aneurysm are associated with bicuspid aortic valve
Risk factors - Smoking, HTN, age greater then 70 and fm Hx.

Question 23

High risk groups for aortic aneurysm

Answer 23

Greater then 65yr, Male, PVD

Question 24

Presentation of Aortic aneurysm

Answer 24

Classic triad of rupture - Hypotension/collapse, Back/abdominal pain and Palpable, pulsating abdominal mass
75% asymptomatic
Commonest presentation is due to acute expansion or disruption of wall = Syncope, pain, hypotension, Pulsatile mass, may have airway or esophageal obstruction
PmHx of HTN, PVD, CAD, COPD, renal insufficiency
Uncommonly - ureteric obstruction or hydro nephrotic, GI bleeding, Distal embolisation.

Question 25

Ix for Aortic aneurysms

Answer 25

``` Blood - FBC,U and E, creatinine, PTT, INR, Group and hold Abdominal USS CT MRI Aorta gram only for EVAR ```

Question 26

Mx of Ruptured AAA

Answer 26

ABCs In imaging Straight to OR Cross match 10 units of packed RBCs

Question 27

Tx of aortic aneurysm

Answer 27

Conservative - reduced CV RFeg stop smoking, control HTN,DM and Hyperlipidemia. Regular exercise, watchful waiting, USS every 6m to 3yr depending on size and location Surgery - indicated when risk of rupture more then risk of surgery. - risk of rupture depends on size, FmHx of rupture, rate of enlargement more then 0.4 cm/yr. symptoms , comorbidities and smoking. - Elective AAA 2-5% mortality - Indications for surgery - rupture, symptomatic, mycotic, associated with Type A dissection or complicated Type B dissection. Cx of surgery - Endoleak Contraindications of surgery - lie expectancy less then 1yr, terminal disease,significant comorbidities eg MI, decreased mental acuity, advance age Types of surgery - open with graft replacement. Cx are early of renal failure, spinal cord injury, impotence, arterial thrombosis, anastomotic rupture or bleeding, peripheral emboli. Late complications are graft infection, thrombosis, aortoenteric fistula,anastomotic aneurysm. - Endovascular aneurysm repair - Good for rupture of AAA with good anatomy. Cx early immediate conversion to open repair less then 1%, groin hepatoma, arterial thrombosis, iliac artery rupture and thromboemboli. Late Endoleak, severe graft kinking, migration, thrombosis, rupture of aneurysm

Question 28

Causes of DVT

Answer 28

Virchow's triad - Endothelial damage - Venous stasis - immobilisation (eg post MI, CHF, Stroke, Postoperative) leads to inhibits clearance and dilution of coagulation factors - Hypercoagulability - either inherited or acquired ( age, surgery, trauma, neoplasms, blood days rasas, prolong immobilisation, hormone related eg pregnancy, APS, HF.

Question 29

Clinical features of DVT

Answer 29

Asymptomatic Unilateral leg oedema, erythema, warmth and tenderness Palpable cord eg thrombosised veins White, acute pain and oedema with massive thrombosis Homan's sign is unreliable

Question 30

Well's score for DVT

Answer 30

- Paralysis, paresis or recent orthopaedic casting of lower extremity - 1 - Recently bedridden (more then 3 days) or major surgery within past 4 weeks. - 1 - Localised tenderness in deep vein system - 1 - Swelling of entire leg - 1 - Calf swelling greater then 3 cm than other leg - 1 - Pitting oedema greater in the symptomatic leg - 1 - Collateral non-varicose superficial veins - 1 - Active cancer or cancer treated within 6 m - 1 - Alternative diagnosis more likely that DVT - (-2) eg Baker's cyst, cellulitis, muscle damage, superficial venous thrombosis. 3-8 high probability 1-2 moderate probability -2-0 low

Question 31

DDX for DVT

Answer 31

``` Muscle strain or tear Lymph anxieties Lymph obstruction Venous valvular insufficient Ruptured popliteal cysts Cellulitis Arterial occlusive disease ```

Question 32

Ix for DVT

Answer 32

D-Dimer only to rule out Doppler USS MRI Venography gold standard

Question 33

What is post thrombotic syndrome

Answer 33

Development of chronic venous stasis signs and symptoms 2rd to DVT Presents: pain, venous dilation, Edelman, pigmentation, skin changes, venous ulcers Tx: extremity elevation,exercise, continuous compression stockings,intermittent pneumatic compression therapy, skin/ulcer care

Question 34

Superficial venous thrombophlebitis

Answer 34

Defined - erythema, induration and tenderness along superficial vein. Usually spontaneous but can be after cannulation. Causes - Infective - suppurative phlebitis, Trauma, Inflammation - varicose veins or Vasculitis, Hematologic eg polycythemia, neo plastic eg occult malignancy - pancreatic. Presentation - pain and cord like swelling, areas of induration, erythema and tenderness. Ix - Doppler Tx - Thin pad over, firm elastic bandage from foot to thigh, for 7-10 days, Bed rest and elevation in severe. May need NSAID it Due to IV Cx, or Heparin is spontaneous,

Question 35

Tx for DVT

Answer 35

LMWH Warfarin - stop LMWH until INR is greater then 2 for 2 days - continue for 3m if 1st episode with transient RF. Indefinite therapy if 1st DVT with ongoing RF or multiple episodes. IVC filters - only if acute DVT less then 4 was and contraindication for anticoagulants. Must come out in timely manner

Question 36

Common medications that interact with warfarin

Answer 36

``` Acetaminophen - interference with Vit K metabolism Allopurinol NSAIDs - GI injury Fluconazole Metronidazole Sulfamethoxazole Tamoxifen ```

Question 37

Varicose veins

Answer 37

Distention of torturous vein due to incompetent valves 10-20% of population Presentation - diffuse arching, fullness/tightness, nocturnal cramping, worse when prolonged standing and premenstral. Can ulceration, hyperpigmentation and induration Tx - elevate leg or compression stockings, Compression sclerotherapy (sodium tetradecyl sulphate), Surgery ligation and stripping.

Question 38

Chronic venous insufficiency

Answer 38

Defined - Venous insufficiency and skin damage Cause - pump dysfunction and valvular incompetence due to phlebitis, varicositis or DVT or venous obstruction Presentation - pain (most common), ankle and calf edema - relieved by elevation. Pruritus, brownish hyperpigmentation (hemosiderin deposits). Stasis dermatitis, subcutaneousfibrosis if chronic. Ulceration - shallow, above medial malleous, weeping (wet), painless,irregular outline. Signs of DVT/Varicose veins/thrombophlebitis Ix - Doppler (most common), Venography (gold standards) Tx - Conservative - Elastic compression stocking, mobilisation, periodic rest elevation, avoid prolonged standing. Ulcers need a multilayer compression bandage, antibiotics PRN - Endovenous - laser or radio frequency ablation, or foam sclerotherapy. - Surgery - only if conversation fails or recurrent ulcers. Surgical ligation of perforators in region of ulcer. ??

Question 39

Carotid stenosis

Answer 39

RF - HTN, smoking,DM, CVD or CAD, dyslipidemia Presentation - Asymptomatic or TIA, RIND or stroke,retinal insufficiency or infarct or temporarily (ipsilateral amaurosis fugax), MCA contra lateral occlusive symptoms Ix - FBC, PTT/INR, Fundoscopy, Carotid Bruits, Carotid duplex, angiogram, CTA Tx - Control HTN, Lipids, DM, anti PLT, Carotid endarterectomy ( greater then 70% stenosis). Endovascular angioplasty or stenting

Question 40

Lymph edema

Answer 40

Define - obstruction of lymphatic drainage resulting in edema with high protein content Cause - primary - milroy's syndrome, Lymphedema praecox, Lymphedema tarda. Secondary - Infection eg filariasis most common world wide or post operative. Malignant infiltration or radiation or surgery - number one cause in 1st world. Presentation - Classically non pitting edema, impaired limb mobility, discomfort pain, psychological distress Tx - avoid injury, skin hygiene with moisture and topical fungal treatment and Tx of bacterial infection. External support - intensive compression bandages or maintenance with Lymphedema sleeve. Exercise gentle daily with increase ROM. Massage and manual lymph drainage. Prognosis - if left untreated subcutaneous fibrosis occur making it resistant to Tx. Cellulitis cause rapid swelling and sepsis and death.

Question 41

Angiogram

Answer 41

Pre operative - Bloods - FBC, Coagulation, G and H, U and E. Imaging - ex, Doppler, ABPI, USS duplex, Peri operative - Heparin Post operative - Dual anti PLT therapy - aspirin and clopitgrel. R/V 6 was after with a bilateral duplex Scan.

Question 42

AV fistula

Answer 42

Pre operative - USS veins and arteries, G andH and U and E Peri operative - Done under nerve block or general. Cut vein and reattach to artery. Heparin is used. Post operative - wound dressing, Rule of 6s, 6 wk R/V 6? Flow, 6mm diameter,6mm for the skin. Cx - bleeding, infection, nerve damage, Steel syndrome(more blood through the fistula then in the arm.