Transcript Clinical Anatomy and Vascular Surgery

Michael G Mount, DO
5/21/2012
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Learn the indications, placement and
complications of central venous catheters
Know the criteria for surgery in Carotid
Stenosis and technical basics of Carotid
Endarterectomy
Understand Abdominal Aortic Aneurysms and
the basics of management
Know the potential surgical options for
correction of peripheral vascular disease
Understand relevant anatomy as it relates to
vascular surgery
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Indications for Central Venous Catheterization
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Monitoring
◦ CVP - central venous pressure, an estimate of Right heart
filling pressure, ScvO2 (central venous oxygen saturations)
a measure of oxygen return to the heart
◦ PA Catheter - pulmonary artery, catheter allows right
ventricle pressure measurements and PAOP (pulmonary
artery occlusion pressure) an estimate of left heart filling
pressures
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Access
◦ Dialysis - or plasmapheresis requires large bore double
lumen into central vein capable of very high flow
◦ Specific Medications
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Seldinger Technique
◦ placement of a wire into a vessel followed by
placement of catheters over the wire
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Anatomic Landmarks
Ultrasound
Locations
◦ Internal Jugular
◦ Subclavian
◦ Femoral
• Deep to sternocleidomastoid
• Superficial and lateral to the
common carotid artery
• Joins with subclavian vein to form
brachiocephalic (inominate) on left
and right
• Palpate between
sternal and clavicular
heads of SCM
• Enter 30 degrees to
skin, aiming towards
ipsilateral nipple
• Landmarks; inferior and lateral to
bend of clavicle, aiming towards
sternal notch, just deep to clavicle,
parallel to ground
• Higher rates of pneumothorax,
lower rates of infection, most
comfortable
• Femoral vein medial and just deep to
femoral artery
• Deep femoral vein and saphenous veins
join at deep surface and anteromedial
surface respectively
• Highest rate of infection
• Potential complications
• Infection (varies with site, lowest with SC, highest with femoral)
lowered by technique, catheter, dressing
• Pneumothorax – SC higher than IJ, lowered by ultrasound
• Pseudoaneurysm – sequelae of arterial puncture or inadvertent
cannulation
• Line migration
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700,000 CVA per year in United States
75 – 85 % ischemic
20 - 60% related to carotid atherosclerosis
7-12% of patients > 65yo have evidence of
atherosclerosis at the carotid bulb
Male > Female
Vascular Risk Factors
Morbidity >> Mortality
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Stroke
TIA (transient ischemic attack)
Amarousis Fugax
◦ intermittent blindness; “shade coming down
over one eye”, due to transient embolic
occlusion of ipsilateral ophthalmic artery
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Syncope
Cervical Bruit
Ultrasound – preferred modality
70-99% stenosis; 89% sensitivity, 84% specificity
50-69% stenosis; 36% sensitivity, 91% specificity
0-49% or 100%; 83% sensitivity, 84% specificity
Trial
Indication
Perioperative
CVA/Death
Risk
Reduction
P Value
NASCET
Sx: ≥70%
5.8%
16.5%/2 yr
<.001
Sx: 50%-69%
6.7%
10.1%/5 yr
<.05
ECST
Sx: 70%-99%
7.5%
9.6%/3 yr
<.01
ACAS
Asx: ≥60%
2.3%
5.9%/5 yr
.004
ACST
Asx: >60%
3.1%
5.4%/5 yr
<.0001
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Symptomatic Patient with 70-99%stenosis
◦ CEA and Best medical therapy
◦ Surgeon with perioperative CVA/mortality <6%
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Recent Completed Stroke
◦ <100% stenosis
◦ Time frame based on CT changes
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Crescendo or Evolving TIA
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Asymptomatic Patient with 80%-99% stenosis
◦ CEA and Best medical therapy
◦ Surgeon with perioperative CVA/mortality <3%
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Asymptomatic Patient 50-79% stenosis
◦ Consider patient specific factors
◦ Operate symptomatic side first, followed by
asymptomatic side
◦ If both symptomatic operate on the dominate side
first
Steps of Carotid Endarterectomy (CEA)
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SCM incision, open carotid sheath, ligate facial vein, obtain
proximal and distal control of CCA, ICA, ECA, Incise and Open
carotid, Shunt vs Stump Pressure vs EEG vs Doppler, perform
Endarterectomy, close with patch
Relevant anatomy
• Facial Vein crosses over carotid birfurcation to the inernal jugular
lying anterolateral to carotid
• Hypoglossal nerve may cross over both ICA and ECA and need to
be retracted; higher up a nerve diving between the two is
glossopharyngeal
• Internal Carotid has no extracranial branches
• Ansa Cervicalis can be divided if needed for exposure
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Mortality 0.5-1%
Myocardial Infarction 2-4%
◦ Most common complication
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Stroke 1-2% Asx patients, 2-6% Sx patients
Cranial Nerve Injury
◦ most common hypoglossal  tongue deviation
towards side of injury (4-17%)
◦ Vagal or recurrent nerve injury from clamping 
hoarseness (1-15%)
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Systemic Blood Pressure Instability
Bleeding requiring reoperation
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Recurrence Rates and Reoperation
Carotid Stenting
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Dilatation of >50% from normal diameter
True vs False
Law of Laplace; T=PR/δ
Can occur at any artery
Usually degenerative
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Increasing Incidence
Screening in certain high risk populations
◦ Ultrasound vs CTA
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Follow patients with known aneurysms
◦ Follow up every 6 months >4.5 cm, yearly >4 cm
+everything else on slide
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Incidental
Screening
Embolization
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Physical Exam
Rupture
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Rupture
Symptomatic
>5.5 cm Men or >5.0 cm Women
Inflammatory Aneurysms
Open Repair vs EVAR
Left Medial
Visceral
Rotation
- Left renal vein crosses aorta  collaterals include left gonadal vein, left
adrenal vein and left inferior phrenic veins, lumbar veins
Ureters cross over common iliacs to reach pelvis
Open Repair
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Impotence – 33%
MI – 6.8%
Renal Failure – 1-8%
Arrhythmia – 9.7%
Pseudoaneurysm – 1%
Graft Infection – 0.4%
Ischemic Colitis
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Proximal neck – cylinder, 15mm long w
diameter 28mm or less
Neck angulation (between suprarenal aorta
and proximal neck) – 60 degrees
Distal landing zone-common iliac less than
18mm in diameter and 2cm in length
Quality of access vessels – 7mm or more
EVAR
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Indications
Early postoperative survival benefit
Differences in Complications
Need for reimaging and reoperation
Endoleak
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=
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Atherosclerosis
Lower Extremities
Signs & Symptoms
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Claudication
Rest Pain
Poor Wound Healing
Ulcers
Dependent Rubor
Hair Loss
Dry Gangrene
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<0.9
<0.5
<0.4
<0.3
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Claudication
Rest Pain
Ulceration
Gangrene
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Ratio of Systolic Blood Pressure in the lower extremity to the
upper extremity
Normal is greater than 1.0.
◦ Symptoms correlate with decreasing ABI
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Can be inaccurate in diabetic patients due to medial calcinosis
(Monckeburg)
◦ use TBI, Plethysmography
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Depends on degree of chronicity and collateralization
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Symptoms are typically one level below the area of narrowing:
◦ aortoiliac disease (AIOD)  thigh and buttock claudication,
impotence (Leriche Syndrome)
◦ femoral disease  calf claudication (most common lesion within
Hunter’s canal, also called adductor canal)
◦ tibioperoneal disease  foot claudication
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Smoking Cessation
Exercise
Statins
ASA
Cilostazol
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Indications
Percutaneous
Balloon
Angioplasty
Stenting
Bypass
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Based on Anatomic distribution of disease
Basic Principles of Vascular Surgery
Graft Choice
◦ PTFE (synthetic), Reversed Saphenous Vein, In-Situ
Saphenous Vein
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Saphenous vein is mapped preoperatively with ultrasound,
exposed along its length and taken off saphenofemoral junction.
Tributaries are ligated. 3mm distended diameter is minimum
required. Line drawn down vein to maintain orientation and
prevent twisting.
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Large single or multiple separate incisions can be made.
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Lymphatic tissue medial to vein is ligated to prevent leak postop
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Incision posteromedial to knee (immediately posterior to tibia if
below), above or below based on area of stenosis is made for
access to popliteal vessels
Posterior fascial compartment is opened and gastrocnemius and
soleus are retracted posteriorly while the adductor muscles are
retracted anteriorly
Artery is located laterally to popliteal vein and tibial nerve
Tunnel is made deep to the sartorius and adductor muscles
- Gastrocnemius medial head may need to be incised to prevent compression of the graft
- Anastomosis is made with running prolene suture
Outcomes
•5 year patency approaches 90%
with saphenous vein above the
knee
•Lower patency for PTFE
•Lower patency for Limb Salvage
•May require Secondary
Interventions for patency
•Follow with duplex ultrasound
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Overall Morbidity ~25%
MI – most common
Mortality ~2-3%
Wound infection
Amputation
◦ End stage vascular surgery