Vascular Surgery

Vascular

THE AORTA

Anatomy

• Enters abdomen @ T12- With azygous vein and thoracic duct
• Branches
  
  • Unpaired branches: Coeliac axis, SMA, IMA
  • Paired branches: Inferior phrenics, Adrenals, Renals, Gonadals, Lumbar x 4
  
  
• Bifurcates into Common Iliacs below umbilicus @ L4

ABODOMIAL AORTIC ANEURYSM

Abnormal permanent  dilatation of the wall (all 3  layers) of the abdominal  aorta

Types

• 80% infrarenal
• The remainder: suprarenal  +/- thoracic aorta

Epidemiology:

M > F = 4 : 1

9th  most common cause of  death in males > 55

1% of men 55-64 have AAA

Aetiology

Atherosclerosis: media  degeneration

Trauma

Inflammatory: P.A.N.

Infective: syphillis, fungal

Congenital: Ehlers Danlos,  Marfans

Types of AAA

• Saccular- Resembles small sac
• Fusiform- Narrow cylinder

Associations:

• Family history++  : family  members should be  screened: 25% chance of  having AAA
• DM
• HTN
• CAD
• COPD
• Hyperlipidaemia

Features

Asymptomatic (70%)

Emboli to lower limbs

Pressure on other  structures

     -Mass effect

     -ie :Ureteric obstruction =  renal failure

Fistula: aorto-caval or  duodenal

Rupture

Asymptomatic AAA	Symptomatic
Incidental finding on : Exam PFA (calcifications) US	Pain: back, loin, groin, iliac  fossa Thrombus/emboli to lower  limbs Compression : duodenum,  IVC, ureter

Rupture

Triad:

• Abdominal/back pain
• Pulsatile mass
• Hypotension

50% of ruptured AAA will  die before reaching hospital

Of the 50% that survive to  surgery

Half of these will die

Retroperitoneal (80%)	Intraperitoneal (20%)
Contained in  retroperitoneum Tamponade effect Classic triad	Collapse Higher MR

Why do patients survive  rupture?

• Tamponade in  retroperitoneum
• Vasoconstriction of non  essential circulatory beds
• Prothrombic state effect
• Drop in BP
  
  • NB: careful with IVF in  rupture: may effect the  above mechanisms
  
  

Risk of rupture @ 5 years :

<5.5cm :                 10%

5.5cm :                 25%

6 – 7cm :                  30 – 40%

>7cm :                 75%

Normal aorta diameter is  2cm

Indications for repair:

Rupture/leaking

Symptomatic

> 5.5cm

Rapid growth : >0.5 cm per  annum

Distal emboli

Emergency Repair	Elective Repair
Emergency Repair Work-up If haemodynamically  stable : ....CT If haemodynamically  unstable: ....OT Routine bloods: FBC, INR,  U/E A.C.T. A = Anaesthesist (contact) C = Crossmatch 10 u T = Theatre	Elective AAA repair If < 5.5cm , risk of  operation is greater than  risk of rupture Annual surveillance : US or  CT Elective AAA work up: Routine bloods + Group x- match 4u Heart: ECG/Echo/Angiogram Lungs: CXR/PFTs CT : to examine Extent of aneurysm  (infra/supra renal) Type ( fusiform/saccular) Is it suitable for  endovascular repair?

Open Repair MR @ 30 days

Elective : 5 – 8%

Emergency symptomatic:  10 – 20%

Rupture : 50%

Open AAA repair: procedure

• Midline laparotomy
• Aorta cross-clamped :  causing huge back pressure  on heart and lower limb  ischaemia
• Sac opened, Dacron graft  inset
• Aortic sac closed over  prosthetic graft to prevent  infection

Open AAA complications

• Cardiac: MI, CCF,  arryhthmias
• Lung: atelectasis, RTI, ARDS
• Bowel ischaemia : as IMA is  ligated
• Distal emboli: ischaemic  limb, trash foot
• Aorto-duodenal fistula
• ARF
• Anastomotic breakdown

• Anterior spinal syndrome  (spinal arteries)
  
  • Paraplegia
  • Incontinence
  • Pain and temp loss
  • Proprioception normal
  
  
• Sexual dysfunction

• Graft infection
  
  • Staph aureus/epidermidis
  • Rx: remove graft and  perform bilateral axillo- bifem graft
  
  

EndoVascular Aneurysm  Repair (EVAR)

• Stent deployed via femoral  arteries
• No need to cross clamp  aorta
• Can de done under regional  anaesthesia

EVAR relative contraindications

• Young patients < 60
  
  •      -? Long term patency
  
  
• Aortic neck < 1.5cm
• Mural thrombus in proximal neck
• Severe iliac disease with strictures
• Angle between neck of aorta and aneurysm >60°
• Renal insufficiency
• Large  patent lumbar vessels

EVAR complications

• Renal failure
• Stent deployed over renal  arteries
• Nephrotoxic contrast
• Cholesterol emboli

• Graft occlusion
• Graft infection
• Graft migration
• Femoral artery  haematoma/pseudoaneurys m
• Distal emboli
• Post implantation syndrome

     -↑T°, ↑WCC, ↑ESR, ↑CRP

Endoleak: 5 types

• Failure of proximal or distal  seal
• Filling of sac via collaterals  (IMA etc)
• Breach in graft material
• Increased porosity of graft
• Endotension: ↑  graft size  without visible leak

AORTIC DISSECTION

Tear in aortic wall

• So blood flows in between  layers of wall forcing them  apart
• Blood enters intima and  then the media – and can  propagate a variable  distance

Classification systems

DeBakey Classification

Type 1	Type 2	Type 3
originates in  ascending aorta and  propagates distal to arch	originates and  confined to ascending aorta	originates in  descending aorta, rarely  propagates proximally

Stanford Classification

A : DeBakey 1 and 2

B : Debakey 3

Aetiology

HTN

Bicuspid aortic valve

Marfans

Turners

Iatrogenic: PTCA, cardiac  surgery

Symptoms

• Classically : severe  “tearing” chest pain
• Chest pain- Dissections involving  ascending aorta
• Back pain- Descending aorta  dissections
• CCF
• Syncope : 2° cardiac  tamponade
• CVA : extension to carotids
• ARF: extension to renal  vessels
• Bowel ischaemia: extension  to SMA
• MI: extension to coronary  vessels
• Aortic regurgitation

Differentials

• MI
• Acute A.R.
• Pericarditis

Investigations

Routine bloods

ECG

CXR

• Widened mediastinum
• Calcium sign: separation of  intimal calcification from  outer border of aorta by  >10mm
• Loss of aortic knuckle

Echo : TOE

CT Thorax

MRA : gold standard

Aortogram

*Ix depends on stability of patient

Aortic Dissection

Medical Management

Aim for MAP of 60-75  mmHg

Reduce shear stress

     -Sodium nitroprusside

Β -blocker

CCBs: verapamil preferred  due to inotropic effects

Aortic Dissection

Surgery Indications:

Acute proximal aortic  dissection

Acute distal dissection with  complications:

     -Vital organ compromise

     -Impending aorta rupture

     -Retrograde dissection  into ascending aorta

     -Marfans or Ehlers Danlos

Surgery

Dacron graft

Bentall procedure

     -Replacement of damaged  aorta and AVR

David procedure

     -Replacement of damaged  aorta and   reimplantation of  AV

Stent and medical Rx

Dr BeBakey devised the  surgery to correct  dissection initially

He is also the oldest patient  to ever receive his own  operation (97 years)

PERIPHERAL VASCULAR DISEASE

Fontane Classification

I: mild pain on walking -  claudication

II: severe pain walking short  distances – intermittent  claudication

III: rest pain

IV: tissue loss (gangrene)

Aetiology

Smoking

DM

Elevated cholesterol + TGs

HTN

Obesity

High levels of homocysteine

P.V.D.

Investigations

FBC: O/R polycythaemia or  anaemia

U/Es: dehydration

ESR/CRP: vasculitis

Fasting lipids and glucose

HbA1c

ABI : 1 is normal

• 0.9 – 0.5 = intermittent  claudication
• < 0.5 = critical limb  ischaemia

*may be spuriously high in  diabetics due to difficulty on  compressing vessels due to  calcifications

Doppler US : to examine  stenosis of FA

Femoral angiogram

CT angio

MRA

Intermittent Claudication

“pain in muscle due to  ischaemia, brought on by  exercise, relieved by rest”

7% will develop critical limb  ischaemia

Pain usually in calf muscles

Differential:

• Spinal stenosis: canal  narrows on hip extension,  widens on flexion, relieved  by sitting.
• Cauda equina
• Venous claudication
• OA

Intermittent Claudication Pathophysiology

• Lesion starts in SFA @ adductor canal (as it becomes popliteal artery after passing through adductor hiatus)
• Claudication after several hundred metres
• Ankle pulses diminish, Bruit at or above canal
• Collaterals develop and symptoms may improve – but unless lifestyle modifications are made : atherosclerosis may progress to critical ischaemia

Critical Limb Ischaemia

• Usually due to several  stenotic lesions
• Features:
• Tissue loss (ulcers,  gangrene)
• Rest pain
• Night time pain
• Ankle BP < 50mmHg

• Night pain
• Starts 1 hr after bed
• Metabolites accumulate : ↓ perfusion, BP and CO :  waking patient up
• Relieved by hanging foot  down or walking
• Can progress so only relief  patient can get is by  sleeping in a chair

The Diabetic Leg

Unique problems

• Arteries calcifies :  surgery/angio difficult
• ABI spuriously high
• Immunocompromised
• Crural vessels affected
• Neuropathy can complicate  ischaemia

Sensory neuropathy

• Minor trauma unnoticed =  so presentation is late
• Proprioception affected:  pressure taken @ unusual  sites whilst walking –  causing Charcots joint  destruction and ulceration

Motor neuropathy

• Extensors of calf and sole  affected : atrophy
• Toes dorsiflex
• So MT heads exposed to  abnormal pressure causing  callus and ulcers

Autonomic neuropathy

• Dry foot: decreased  sweating causing scaling  and fissuring
• So bacteria can enter

Venous ulcers

Arterial ulcers

• Punched out, painful,  pressure areas
• Base: exposed bone,  tendons

Neuropathic ulcers

• Punched out, pressure  areas, painless

Treatment of PVD

Best Medical Therapy

• Control risk factors :  smoking, lipids, glucose,  HTN and obesity
• Antiplatelet agent: aspirin  or clopidogrel
• Exercise
• Pentoxifylline
  
  • Decreases blood viscosity
  • C/I: NYHA Class III/IV
  
  

Endovascular : PTA

Indications:

• Aortoiliac disease
• Suitable SFA lesion
• Disabling claudication

Safe, quick and cheap

Can be repeated

Most patients with critical  limb ischaemia have  multilevel disease so are  not candidates

Arterial Reconstruction

Indications:

• Limb salvage
• Peripheral embolization
• Incapacitating claudication

Intermittent Claudicants:  not ideal candidates

• As soon as graft is placed,  collaterals involute so if  graft occludes : ischaemic  limb
• Surgery on one side reveals  symptoms on the other
• Grafts have  finite patency

Types:

• Endarterectomy:
  
  • Removal of plaque and  thrombus/embolus
  • Ie common femoral  endarterectomy and  profundoplasty
  
  

• Bypass Graft : necessary  conditions
  
  • Good inflow
  • Suitable conduit
  • Good outflow
  
  

Bypass Graft : conduit  types

• Autogenous: Ipsilateral long saphenous  vein -Vein is reversed or  valvotome used so valves will  not impede flow
• Prosthetic:-PTFE or Dacron

Vein Graft

• Advantages: no cost,  superior patency, resistant  to infection
• Disadvantages: small  calibre, often diseased as  well

Prosthetic Graft

• Advantages: easy to use,  variety of calibers/lengths
• Disadvantages: expensive,  prone to infection, poor  long term patency, cannot  be used crossing a joint or  below knee (will occlude)

Bypass graft types

• Anatomic: new conduit  follows old course ie fem- pop bypass
• Extra-anatomic: does not  follow old course ie axillo- bifem bypass

Fem-Pop disease

• Fem-pop bypass
• Fem distal bypas (posterior  tibial artery etc)
• Profundoplasty (creates  good collaterals)

Aorto-iliac disease

• Aorto-bifem bypass
• Fem-fem crossover

• Axillobifem
• 
• Endarterectomy

Arterial Reconstruction  complications:

• Graft occlusion
• Graft Infection: must be  removed- Prevented by: autogenous  material, perioperative Abx,  aseptic technique
• MI: patients are  arteriopaths

ACUTE LIMB ISCHEAMIA

Aetiology

• Embolism
• Thrombus
• Trauma
• Dissecting aneurysm
• Raynauds (UL)

Emboli causes

• A Fib: Left atrium
• Mural thrombus post MI
• Valvular heart disease
• Aneurysm
• Foreign body
• Iatrogenic

Features:

6 P’s

• Pain
• Pallor
• Paraesthesia
• Pulseless
• Paralysis
• Perishing cold

Management:

• Hx + Exam
• Routine bloods
• IV Heparin
• Analgesia
• Imaging: embolus v  thrombus

Embolus Rx:

• Embolectomy : arteriotomy  performed proximal to  occlusion
• Fogarty catheter passed  distal to embolus and  pulled proximally to “catch  clot”
• If fails: arteriogram +/-  thrombolysis +/-  endarterectomy

Thrombus Rx:

• Angiogram and catheter advanced via femoral artery to thrombus
• Heparin 1000u/hr +/- tPA
• Success rate 65%
• Thrombolysis can be accelerated by:
  
  • Pulse spray through multiple  side hole catheter
  • Aspiration thrombectomy -  debulking thrombus  aspiration
  • High dose over shorter time
  
  

Progress

Initial - marble white limb

Then mottling- Light blue-purple, spasm↓, skin fills with deoxygenated Hb : still salvageable

Later- darker., coarser non blanching mottling : coagulated blood

Later still:- Blistering and bacterial putrefaction (gangrene)

N.B. Fasciectomy may be  required to prevent  compartment syndrome

Compartments:

• Upper limb: 2
• Thigh: 3
• Lower limb: 4

Complications of Rx:

Reperfusion injury:  myonephropathic syndrome

   -activated neutrophils, free  radicals, enzymes, K+, CO2  etc...can cause:   ARDS,  myocardial stunning,  endotoxaemia, ATN.

Compartment syndrome

   -remember pulses are present , PAIN ON  PASSIVE  MOVEMENT

other ANEURYSM

Iliac Aneurysms	20% of AAA extend into  common iliacs If isolated:    -Rx: endovascular or  surgical repair If due to AAA extension:    -Rx as AAA
Femoral Aneurysms	70% bilateral 80% associated with AAA 40% associated with  popliteal aneurysm 3 types: 1.  Non specific aneurysm (spontaneous) Usually bilateral Can compress femoral  nerve and vein Usually asymptomatic Rupture extremely rare Femoral Aneurysms 2.  Anastomotic false aneurysm Usually up to 10 years post aorto-bifemoral bypass Caused by:      -Anastomotic disruption due to late suture failure      -Increasing femoral artery occlusion 3.  Iatrogenic Pseudoaneurysm PTA, surgery, trauma
Popliteal Aneurysms	Occur in 20% of patients  with AAA 50% bilateral Often associated with  trauma ; horseriding Complications: Distal emboli : trash foot Acute thrombosis Rx: Thrombolysis with catheter Outer part : heparin Inner part: lytic agent Ligation and vein bypass
Pseudoaneurysms	The result of trauma to all  three layers of an artery  resulting in a haematoma  that contains the bleed. This haematoma must  continue to communicate  with the artery to be  considered a  pseudoaneurysm Does not contain any of the  layers of the vessel wall Most commonly femoral artery 8% of procedures via femoral artery result in pseudoaneurysms – usually resolve spontaneously Rx: US compression Thrombin injection Radiological coil insertion Surgical repair

VARICOSE VEINS

Dilated, tortuous,  superficial veins

Usually on lower limbs

Failure of the valve leaflets  so blood regurgitates  distally

Aetiology:

Reflux disease: 90%

Post thrombotic: 10%

Veins

Telangiectasiae: 0.1 – 1mm

Reticular veins: 1 – 4mm

Varicose veins: >4mm

Symptoms

Aching legs: worse when  standing

Ankle swelling

Venous eczema: redness,  dryness, itch 2°  haemosiderin deposition

Spider veins  (telangiectasia)

Atrophie blanche (scar like  ankle patches)

Restless legs syndrome

Complications:

Pain

Dermatitis

Ulceration

Carcinoma/sarcoma in  longstanding ulcers

Superficial thrombophlebitis

Bleeding

On exam:

Dilated veins

Skin changes in gaiter area  (medial 1/3 of leg)

Venous stars: intradermal  blue patches

Oedema + atrophie blanche

Lipodermatosclerosis:  sclerosis of skin and subcut  fat by fibrin deposition –  inverted champagne bottle

Investigations

Routine bloods

Duplex doppler

Ambulatory venous  pressures

Treatment:

Conservative:

• Weight loss
• Exercise
• Leg elevation
• GCS Grade 2: 30-40mmHg :  check ABIs first

Surgical treatment:

Venous stripping :

   -ligation of SFJ

   -vein stripped to below knee

   -multiple stab phlebectomies

Complications:

Recurrence : 10% @ 10 years

DVT/PE

Bleeding/bruising

Unable to use saphenous for future arterial bypass or CABG

Nerve injury: sural or saphenous nerve

Wound infection : 1%

No symptom improvement

Other techniques:

• Sclerotherapy
• Endovenous laser and  radio-frequency ablation
• Subfascial Endoscopic  Perforator Surgery (SEPS) :  for incompetent perforators

VENOUS ULCERS

Arise due to venous  hypertension

• Arteries no longer have  high pressure
• Blood pools
• Fibrinogen leakage
• Free radicals released
• Chronic wound formed

Usually arise on the gaiter  area

Describe

Variable size

Edge

Sloping and purple

Base

Slough or granulation tissue

Treatment options:

Bisgaard regime

The 4 E’s

• Education
• Elevation
• Elastic compression
• Evaluation

Compression therapy

Profore dressings:

• Inner wound contact  layer : non adhesive
• Absorbent padding: stable  fleece
• Crepe bandage : holds  padding in place
• Class 3a elastic  compression bandage
• Class 3b cohesive bandage  acts as retaining layer

Larvae therapy

• Debride dead tissue and  cleanse it
• Viable tissue left alone
• Necrotic, suppurative and  gangrenous wounds best  suited

Vac therapy

• Vacuum-Assisted-Closure
• Promotes granulation tissue
• Venous Ulcers
• VAC should be changed q  2/7
• Easily recognised by black  foam in wound (and large  loud VAC machine at the  end of the bed!)

Skin grafting

Complications

Infection

Malignant change: Marjolins  – SCC

Osteomyleitis

LYMPHATIC DISEASE

Lymphoedema- Interstitial oedema of  lymphatic origin – therefore  high protein

Causes:

Primary

• Lymphoedema Congenita- Presents in first year ol life  (Milroys disease)
• Lymphoedema Preacox- Unilateral or bilateral
• Lymphoedema Tarda- Presents > 35 yrs

Secondary

• Filarial
• Malignancy
• Surgical lymphadenectomy
• RTx
• Trauma
• Chronic  infection/inflammation :  cellulitis, RA

Investigations:

Radioisotope lymphography

Contrast  lymphoscintigraphy

US

CT

MRI

Treatment:

Conservative:

• Physio
• Compression bandages
• Manual lymphatic drainage  (MLD)
• Prevent infection
• Diuretics

Indications for surgery:

• Marked disability/deformity
• Lymphocutaneous fistula
• Proximal obstruction with  patent distal lymphatics

Surgical:

Homans procedure

   -lymphoedematous tissue  excised

Charles procedure

   -all skin and sucut tissue  excised

Lymph Drainage procedure

   -lymphovenous  anastomosis

Differential for swollen leg

• Non vascular/lymphatic:  CCF, Renal/Liver failure,  Bakers cyst, trauma,  Achilles rupture
• Venous: DVT, post  thrombotic limb, venous  malformation (Klippel  Trenauny), external  compression ie Ca
• Arterial: reperfusion injury,  AV malformation, Aneurysm

Vascular Exam

Arterial

General Inspection :

Colour- Pallor or erythema

Trophic changes

• Hair loss
• Skin loss
• Shiny skin
• Brittle nails
• Gangrene (dry=mummified, wet=infected)

Ulcers

• Site, size, shape, scars,  surrounding skin etc
• Base, edge, depth,  discharge
• Make sure to : look between  toes and heel
• Muscle wasting
• Venous guttering : poor  arterial inflow produces  decreased venous outflow

Palpation : arterial

• Temp: with back of hand
• Capillary refill
• Pulses
  
  • Femoral: mid inguinal point
  • Popliteal
  • Posterior tibial : 2 cm  posteroinferior to MM
  • Dorsalis pedis : lateral to  EH tendon
  
  

Buergers Test ; lift leg @  heel

• Normal if toes pink @ 90°
• Pallor @ 30° indicates  ischaemia
• Severe ischaemia if pallor  @ <20°
• Hang foot over side of bed  looking for reactive  hyperaemia

Bruits over femoral artery

To conclude:

• Listen and feel carotids
• Feel for AAA and radial  pulse
• Say you would like to do  ABIs

Venous

General Inspection:

Oedema

Varicose veins : LSV or SSV  course

Lipodermatosclerosis

Haemosiderin deposition

Eczema

Venous stars

General Inspection: Venous

Ulcers : as before

• Site, size, shape
• Base, edge, depth,  discharge

Palpation : Venous

Feel varicosities

Trendelenburg – tourniquet  test

• Doppler is far more  accurate
• WHOOSH-WOP =  competent SFJ
• WHOOSH-WHOOP =  incompetent SFJ

Tap test : Chevriers sign

• Palpable wave conduction  = incompetent valve