Vascular Flashcards
What are the indications to operate on AAA for men? For women?
Why was this size chosen?
Men > 5.5cm
Women > 5cm because women have higher risk for rupture (x4.5 times higher)
Size chosen because the risk of rupture at 5.5cm (~5%/yr) was about the same as the mortality risk from operating.
What is the most common perioperative complication after AAA repair?
What is the incidence of this complication?
Cardiac event. (~15%)
Cardiac stents and AAA
How long do you wait after bare metal stent?
Drug eluting stent?
Plavix- stop or continue for open AAA vs EVAR?
Bare metal: 4-6 weeks
Drug eluting: 1 yr
Plavix- stop 10 (or 5) days pre-op for open. Continue through surgery for EVAR
A pt in the ED complains of back pain. BP 85/50. pulsatilr abdominal mass. You suspect a ruptured AAA but the patient is awake and talking to you. Next best step?
A) give blood and resuscitate B) beside ultrasound C) CTAP D) emergent transfer to OR E) diagnostic angio
Answer is C. CT scan.
Giving blood and resuscitating can increase bleeding
Ultrasound may not be able to see the rupture
only 15% of pts with rAAA die within 2hrs of presentation
CT scan provide better information for endovascular repair planning
EVAR requirements
Proximal aortic neck length
Proximal aortic neck diameter
Proximal aortic neck angulation
External iliac artery diameter
Proximal aortic neck length >10 mm
Proximal aortic neck diameter <32 mm
Proximal aortic neck angulation <60 degrees
External iliac artery diameter >7 mm
Is diabetes a risk factor for AAA?
Actually if you have diabetes you have lesser odds of having an aneurysm
What is an average growth rate for aneurysm
~10% a year
AAA pre-op Eval
- when do you do EKG
- when do you do echo
- when do you do stress test?
- EKG on EVERYONE
- echo for (+) dyspnea or heart failure
- stress test: pts with unknown fx status or if they have 3 or more CV risk: CAD, CHF, stroke, diabetes, renal
Pre-op placed bare metal stent. What to do?
Drug eluting stent?
What to do with plavix for open AAA vs. EVAR?
Bare metal: delay surgery 1 month
Drug eluting: delay 1 year
angioplasty: 2 weeks
Open: stop plavix 10 days prior
EVAR: continue plavix through surgery
Problem with US for evaluating for AAA rupture?
May not be able to tell there’s a rupture or not
Mortality for patients who presented to the ED with ruptured AAA within 2 hrs?
15%
For AAA repair mortality for suprarenal clamp vs infrarenal?
Mortality is the same
When you’re doing AAA, is it okay to divide the left renal vein?
Yes it it. Divide it as close to the IVC as possible. That way it will preserve the collaterals (gonadal, adrenal, lumbar veins)
Who needs IMA reimplantation?
T/F: if a pt has a large meandering IMA, that means the collaterals are sufficient and there is no need to reimplant the IMA
- celiac/SMA occlusive disease
- prior colon resection
- poor IMA backbleeding (means the collaterals are not strong)
False. enlarged meandering IMA shows that the pt is living off of this IMA and collateral is not great. Better reimplant this
For AAA repair, why prep and drape before induction?
When theyre awake, they’re muscles may be tamponading the bleed. When they go to sleep, all those muscles go out the window and the pt may start crashing
Describe gaining proximal control for AAA repair
1) take down left lobe of the liver
2) make sure they have an OG. Move the esophagus out of the way
3) find and divide the crus of the diaphragm
4) with the clamp, get all the way down to the spine and clamp
Describe the different types of endoleak
I: proximal or distal seal zone leaks II: backflow from aortic branches III: graft separation IV: pores in the graft V: sac enlargement in the ABSENCE of a detectable leak
EVAR requirements (4)
1) proximal aortic neck length >10mm
2) proximal aortic neck diameter <32mm
3) proximal aortic neck angulation <60 degrees
4) external iliac artery diameter >7mm
Minimal aortic neck thrombus
What is the risk of endoleak over 10 years after EVAR?
25%
Rate of intestinal ischemia after elective AAA repair?
Rate after ruptured AAA open vs EVAR?
Elective: 2%
Ruptured: 40% open, 20% EVAR
Aortoenteric fistula
CTA vs. endoscopy which one is better?
Treatment?
CTA (almost 94% sensitivity). look for air around the graft.
old Treatment
Vasc: do ax bifem. Next day, aortic explant
GI: separate the aorta and the bowel and close the visceral tear
new Treatment:
endovascular stent first + open repair
EVAR complications
- Hypotension after withdrawal of delivery sheath
- severe leg claudication 6 months after endograft
- Hypotension after withdrawal of delivery sheath: iliac artery injury. Balloon tamponaded then stent graft
- severe leg claudication 6 months after endograft: endograft thrombosis. Thrombectomy or fem-fem bypass
Non-obstrucing colon cancer and operative AAA. What do you do?
Repair AAA first
Resect colon in 4-6 weeks
AAA + obstructive, perforated, or bleeding colon cancer. what do you do?
Colon resection/diversion followed by AAA repair
Renal/ovarian malignancy + AAA?
Can do at the same time
Gallstones during open repair
Avoid concomitant cholecystectomy
Indication for thoracic aortic aneurysm repair?
Higher or lower risk of repair compared to AAA?
Repair when > 6cm
Higher risk of repair compared to AAA (Spinal cord ischemia, renal failure, visceral ischemia, resp failure)
Median size of thoracoabdominal aneurysm rupture?
Risk of paralysis after repair?
Mortality rate?
7cm
7-15% paralysis
5-10% mortality
Femoral/popliteal artery aneurysm.
What is the risk?
What % is associated with AAA?
Treatment elective vs emergent?
Risk of thrombosis or embolism
40-60% have AAA
Elective: autogenous vein bypass, aneurysm exclusion
Emergent: thrombolysis (to improve outflow) followed by bypass
When do you do surgery for splenic artery in pregnant women?
What operation?
Always. Because there is near 100% fetal loss with rupture
Ligate, splenectomy
angioembolization can be definitive
Treatment for infected pseudoaneurysm?
Ligation and muscle flap coverage
Person with DVT now has acute arterial emboli. What test to confirm etiology?
TEE to look for PFO
Most common site of arterial emboli?
Common femoral
Most commonly missed compartment during fasciotomy?
Anterior. Often the incisions are made too posteriorly
How do you calculate the ABI?
Cuff around ankle
Systolic pressure of ankle at which Doppler signal appears
Over
Higher of the 2 brachial bp
What to do for
- complete aortic occlusion now has claudication
- complete aortic occlusion with threatened limb, high surgical risk
- common femoral stenosis/occlusion
- aorto bifem
- ax bifem (can be done under local)
- femoral endarterectomy. Do not stent
No stent zones:
Common femoral
Profunda
Popliteal
What is the May-Thurner syndrome?
Compression of the left common iliac vein by the right commom iliac artery
Pradaxa, eliquis, Xarelto.
Other names and their mechanism?
Pra(DA)xa: (DA)bigatran. (D)irect thrombin inhibitor
idarucimab (praxbind) or dialysis
Eliquis: apixaban. Xa inhibitor
PCC
least renal clearance (use in renal pts)
Xarelto: rivaroxiban. Xa inhibitor
PCC
How long to anticoagulate for
DVT due to reversible cause? (Line)
3-6 months
How long to anticoagulate for
Unprovoked proximal DVT vs. distal DVT?
proximal unprovoked: extended therapy
distal unprovoked: 3 mo.
How long to anticoagulate for
DVT and cancer?
Lovenox 3-6 months then Coumadin indefinitely
What is the treatment for phlegmasia cerulean dolens?
When do you do surgery?
Start hep gtt
Fluid resuscitation
Elevate limb
Prepare for lysis
Surgical intervention: failure of initial management or compartment syndrome
What is the most common complication after surgery or endovenous procedure for varicose veins?
Recurrent varicose veins (15-30%)
What should you do if a pt gets a PICC line thrombus and the PICC still works?
Leave it in if the pt needs it still. If you take it out then the other PICC will most certainly clot again.
What is PSV and EDV in carotid duplex?
What velocities indicate 50-70% stenosis? >70? 80-99%?
Peak systolic velocity
End diastolic velocity
Any PSV > 125 means stenosis > 50%
Any EDV > 110 means stenosis 80-99%
> 70% stenosis is PSV > 230 or EDV 90-110
What’s a NASCET trial
For symptomatic.
Measured stroke rate in Best medical therapy (26%) vs CEA (9%)
What’s the ACAS trial?
For asymptomatic carotids.
Stroke rate in best medical therapy (12%) vs CEA (5%)
Indications for CEA for asymptomatic vs symptomatic
Asymptomatic >70%
Symptomatic > 50%
You do a CEA. IN PACU pt has Neuro deficits after waking up. What is the cause and what do you do?
Thrombosis due to technical error. Re-explore, do thrombectomy or angio
You do a CEA. In PACU pt has neck fullness and respiratory difficulty. What do you do?
Cervical hematoma. Take back to OR. intubate and evacuate. No reason to do it in PACU
You do a CEA. Pt has tongue deviation. Reason? What do you do?
Hypoglossal nerve injury. Deviates to the side of the injury. Swallow eval, observe
Most likely source of atheroembolism for right foot?
Right SFA
CEA -> swallowing difficulty. Diagnosis? Treatment?
Glossopharyngeal nerve injury.
Swallow eval. Often need a feeding tube.
Treatment for postCEA headache 2-10d post-op?
Cerebral hyperperfusion
CT head, ICU, bp control
What is the subclavian steal syndrome?
what’s steal syndrome after AV fistula?
Subclavian artery stenosis. No blood to the arm from subclavian.
Instead, blood comes from the ipsilateral vertebral artery. Much smaller caliber. So if you use the arm, blood supply is not as adequate as the subclavian
AVF steal is when the blood doesn’t go distal to the AVF so the hand becomes ischemic. treatment is DRIL. Distal revasc, interval ligation
What is one bypass where PTFE is better than being graft?
Carotid subclavian bypass
What is the treatment for subclavian steal syndrome?
Balloon angio, stent
Or carotid to subcl bypass
Neuro vs venous thoracic outlet syndrome.
- which is more common?
- which one is associated with repetitive motion?
- which one is associated with arm edema, cyanosis?
Neuro (95%) > venous (3%)
Venous -> repetitive motion
Venous: edema cyanosis
Neuro: paresthesia, pain
Treatment for Neuro vs venous thoracic outlet syndrome?
Neuro: scalene resection +/- 1st rib rxn
Venous: 1st rib rxn, post-op angio
Neck zone I. Incision for R CCA or R SCA exposure after stabbing?
Sternotomy
Neck zone I. Incision for proximal L SCA exposure?
Left anterior lateral thoracotomy or trap door
Neck zone II stab wound. Incision
Along anterior SCM
How do you expose the vertebral arteries?
Same as carotid but go lateral to the carotid sheath
And then expose the bony foramen
Amputation rate if you ligate an iliac artery because of trauma?
40%. So try to fix them if you can
Hepatic artery injury. If you’re deciding to ligate it, what else should you do?
Cholecystectomy
Treatment for av fistula infection?
If it’s a graft you take it out
If it’s an autologous vein fistula (not a ptfe graft) then Antibiotics for 6 weeks. Remove only if source of septic emboli
For central lines, which site has higher rate of arterial puncture?
IJ (3%) > subclavian (0.5%)
Mortality rate if you ligate the IVC for severe trauma?
60% mortality
40% survival
What is Paget-Schroetter syndrome?
venous thoracic outlet syndrome
What is nutcracker syndrome (vein)
left renal vein between the SMA and aorta. get varicocele because left testicular vein can’t drain
nutcracker esophagus: diffuse esophageal spasm ish thing extended myotomy
sma syndrome: duodenum pinched between SMA and aorta. do a DJ or ligament of treitz release
What is EHIT and its classifications
Endothermal heat induced thrombosis. radiofrequency or laser treatment for varicose vein and then pt gets DVT
EHIT I: saphenofemoral or saphenopopliteal junction. aspirin
EHIT II: femoral or popliteal extension. <50% occlusion. aspirin
EHIT III: femoral or popliteal extension > 50% occlusion. anticoagulate
EHIT IV: total occlusion. anticoagulate
Someone was treated for PE. At 6 mo. Follow-up, pt has LE edema, sob, hemoptysis, leg swelling, dyspnea on exertion, atrial gallop. Whats the diagnosis? Is this recurrent PE?
What is the incidence of this disease
pulmonary hypertension
~4% of pts after a PE
What’s the ABI for claudication or poor wound healing?
ABI for critical limb ischemia?
0.5 < ABI < 1 is claudication/poor wound healing
ABI < 0.5 is critical limb ischemia
What is leriche syndrome?
Difference in mean pt age compared to infrainguinal vascular disease?
Critical limb ischemia common or uncommon?
Triad you see with aortoiliac occlusive disease.
Absent femoral pulse
Thigh and buttock claudication
Impotence
Tends to be in younger pts compared to infrainguinal disease
Critical limb ischemia uncommon due to rich collaterals (circumflex & inf. Epigastric)
For retrograde mesenteric bypass, what are your inflow vessels and why is it better tolerated in high risk pts?
Common iliac or infrarenal aorta
Because it doesn’t involve supraceliac aortic clamping
Angioembolization for carotid body tumors. When is it performed and why?
Any size indications?
48hrs prior to surgery, to reduce bleeding and size.
Size > 3cm
Carotid body tumor is encasing the carotids. What do you do?
Do en Bloc resection, reconstruct with Interposition graft
Where is the dissection plane for carotid endarterectomy to remove the plaque? What layers of the artery are left behind after the endarterectomy?
Should you extend your arteriotomy to external carotid to remove residual plaque?
Acceptable stroke rate?
Between intima and media. Deep layers of the media and adventitia are left behind to prevent aneurysm
Don’t extend arteriotomy to external carotid. Complicated patch
<6% is acceptable stroke rate
What % of population has accessory renal artery?
Does the right renal artery go in front of or behind the vana cava?
Renal arteries typically originate at what vertebral lvl?
25-30%
Right renal a. Goes behind the vena cava
L2
Pt scheduled for CABG next week. Has TIA today. What to do?
Do combined CABG and CEA. Symptomatic 50-99% in men, 70-99% in women.
Asymptomatic 80-99% also qualifies for simultaneous repair
When do you need to anticoagulate for SVT?
Within 5cm of saphenofemoral junction
Thrombus is longer than 5cm
What’s the ABI for rest pain?
What’s the chance of major amputation for rest pain?
~0.5
Up to 40%
Cut leads to lymphangitis. Most common organism?
Strep pyogenes
What mandates a shunt during a CEA?
Any signs of poor cerebral perfusion or
Stump pressure <50 mmHg (it represents the pressure from the other side via circle of Willis)
SMV usually lies to the left or to the right of the SMA? In front or behind?
Transverse arteriotomy for sma embolectomy should be made where? Over the embolus? Proximal or distal to the middle colic?
How much of the artery should you expose?
SMV lies to the right of the SMA and anterior in the first 3cm
After 6cm it may be to the left of SMA
Proximal to middle colic origin so pretty high up
About 3-4cm
Which statement is false?
- hypertension is the most significant risk factor for a stroke
- carotid disease is the most common cause of ischemic stroke
uncontrolled hypertension is the most significant risk factor for stroke
Cardioembolic disease is the most common cause of ischemic stroke
What the FUCK is the difference between PTT and aPTT?
what’s the normal range vs therapeutic ranges for PTT and aPTT?
aPTT is PTT with an activator added. It just makes it more sensitive
Normal PTT: 60-70s
Normal aPTT: 30-40s
Therapeutic PTT: 120-140s
Therapeutic aPTT: 60-80s
What is the dose of initial heparin bolus?
What is the rate of heparin gtt?
80 units/kg bolus
18 units/kg gtt
Acute renal failure rate for elective AAA repair vs ruptured?
2% for elective
20% for ruptured
Vessel lumens are not compromised until what % of the lumen is stenosed?
40%
Most common organism for central venous catheter infection?
Most commonly organism for peripheral IV/thrombophlebitis?
Central: staph epi
Peripheral: staph aureus
What is the most common location of peripheral artery aneurysm?
Popliteal
What is the most likely outcome of an untreated jugular suppurative thrombophlebitis?
Empyema
Vein vs. graft. Which one is more likely to succeed from bypass thrombectomy?
Graft bypass is more likely to succeed from thrombectomy
What is Well’s criteria?
Scoring to assess likelihood of PE
Clinical symptoms of DVT (leg swelling/pain): 3 pts
Other diagnoses less likely than PE: 3 pts
HR > 100: 1.5 pts
Immobilization for >3 days or surgery within 4 weeks: 1.5 pts
Previous DVT/PE: 1.5 pts
Hemoptysis: 1 pt
Malignancy: 1 pt
> 6: high prob
2-6: moderate prob
<2: low prob
> 4 pts: likely
<4 pts: unlikely
When varicose veins are left untreated, what happens?
It will progress into chronic venous insufficiency and then venous stasis ulcers
For air embolism what position should you place the pt? Right lateral decubitus? Left lateral? Trendelenburg? Reverse T?
Head down, left side down
Left lateral decubitus, trendelenburg. Try to trap the air at the apex of the right ventricle
Is AKA ever preferred vs BKA?
Wound healing/complication rate of AKA compared to BKA?
Where should you transect the femoral shaft for AKA?
What % of pts ambulate after AKA?
what nerve should be identified and preserved during AKA? what happens if you don’t?
in non-ambulatory pts yes
AKA actually heals better than BKA
At least 12cm from the knee joint
40-50% ambulate
sciatic nerve. neuroma formation
Skin changes are early or late sign of acute limb ischemia?
What does a biphasic signal signify vs monophasic?
Skin changes are late signs
Biphasic rules out acute limb ischemia
Monophasic means proximal occlusion and distal reconstitution
What should be given first in DIC?
List 4 things to give in the right order
FFP then cryo then calcium and platelets
Do cancer pts with DVTs need indefinite anticoagulation?
If malignancy can be treated, 3-6mo is enough
If malignancy can’t be treated then maybe indefinite
INR is therapeutic today. D/c heparin gtt?
Heparin gtt needs 2 days of overlap with INR being therapeutic to protect from recurrent VTE
Do you need to anticoagulate superficial femoral vein thrombosis?
Yes the name superficial femoral is a misnomer. SFA is in fact a deep vein
Do you need to anticoagulate popliteal vein thrombosis?
Yes
Amaurosis fugax. Ipsi or contra?
first branch of internal carotid?
first branch of external carotid?
what supplies the cervical esophagus?
what supplies the parathyroid glands?
Ipsi internal carotid.
Ophthalmic artery. First branch of ica
first branch of external carotid: superior thyroid
inferior thyroid artery supplies the cervical esophagus
inferior thyroid supplies the parathyroid gland
Brachiocephalic fistula post-op. Pain and numbness in hand. (+) Radial/ulnar. Incision is clean. Grip strength is weaker. What is the next step?
Ligate the fistula. Ischemic monomelic neuropathy from steal
Which one is the strongest risk factor for AAA?
fat Diabetes Smoking Hypertension Family history
Smoking. 3.5x risk
Diabetes is protective against AAA
What numbers do you expect to see on the ultrasound in carotid stenosis @ 70%?
Peak systolic velocity (PSV) > 230
End diastolic velocity (EDV) 90-110
ICA/CCA > 4
What’s considered rapid expansion in AAA surveillance?
> 7 mm/year
How to distinguish between thrombosis, embolus, and arterial stenosis
Thrombosis usually has h/o claudication
Embolus: otherwise healthy person. All the sudden
Arterial stenosis: collateral vessels. Ischemia not as significant
Between which vessel layers is the CEA plane?
Between intima and media. So deep layer of media and tunica adventitia are left intact
SMA bypass. Where does the inflow come from if you cant cross clamp the supraceliac aorta?
From common iliac
For SMA exposure when to use anterior approach vs lateral approach?
For embolectomy
Anterior approach: lift the transverse colon
For bypass
Lateral approach: formal mobilization of the 4th portion of the duodenum or the ligament of treitz
Size indication for repair of femoral artery aneurysm?
Popliteal artery aneurysm?
Femoral: 2.5cm
Popliteal: 2cm
Pseudoaneurysn: Size indication for surgical repair?
> 5cm or wide neck
What is the natural history of an untreated venous stasis/reflux disease?
Venous stasis ulcers
T/F ischemic strokes are most commonly due to carotid disease
False. Most commonly from cardioembolic disease
What should the blood pressure difference be when left arm is normal and right atm has weakly palpable pulse?
Difference greater than 10-20mmHg indicates significant stenosis
what’s the incision for:
- proximal left subclavian artery
- origins of the right subclavian artery
- distal left subclavian artery
- distal right subclavian artery
- proximal left carotid artery
- proximal right carotid artery
- proximal left subclavian artery: left anterior thoracotomy (this is the only one that needs left anterior thoracotomy)
- origins of the right subclavian artery: sternotomy
- distal left subclavian artery: left supraclav incision
- distal right subclavian artery: right supraclav incision
- proximal left carotid artery: sternotomy
- proximal right carotid artery: sternotomy
T/F h/o DVT increases the risk of chronic venous insufficiency
True
What is the incidence of acute kidney injury after repair of ruptured AAA?
what about ischemic colitis?
Acute kidney injury: 20%
Ischemia. Colitis: 40% with open, 20% with EVAR
How do you distinguish between lymphedema vs DVT in lower extremity edema in a vascular pt with bypass?
Lymphedema: pitting edema. Couple months postop
DVT: less likely to cause pitting edema. Pretty soon postop
Mechanism of renal artery stenosis. What layer?
Media gets thickened. Collagen formation
apparently distal DVT is fine. proximal DVT you can’t just watch
superficial femoral vein - anticoagulate
popliteal - anticoagulate
arterial shunt for trauma
- is there a limit to how long they can have this shunt?
- arteries in the torso or extremities have more complications? why?
- anticoagulate?
- <6 hrs is ideal. more than that you get complications
- torso shunts have less complications because the caliber tends to be bigger
- AC controversial
what compartment pressure is an indication for fasciotomy?
what is delta p and what delta p value is an indication for fasciotomy?
compartment pressure > 30
delta p = diastolic - compartment pressure
delta p < 30 is an indication for fasciotomy
carotid stenting vs. CEA based on CREST trial
- 30-day stroke rate
- composite end point of stroke, myocardial infarction, and death between CAS and CEA
- stroke risk in patients > 80yo
- risk of MI
stent has worse 30d stroke rate
no difference in composite end point of stroke, MI, death
CEA has lower stroke rate in pts > 80
stent has better MI rate
CEA is better bc lower MI, but more strokes
most commonly affected compartment for compartment syndrome?
most commonly missed compartment during fasciotomy?
anterior
anterior
