Vascular

Question 1

What conditions predispose to thoracic aortic aneurysms?

Answer 1

Marfan’s syndrome

Vascular Ehlers-Danlos syndrome

Turner syndrome

bicuspid aortic valve

Question 2

What is the medical management of aortic aneurysms?

Answer 2

smoking cessation

avoiding spikes in BP (no heavy lifting)

BP controls with beta blockers and ACEIs/ARBs

Question 3

What is the Stanford classification for aortic dissections?

Answer 3

type A: involving the ascending aorta

type B: NOT involving the ascending aorta

Question 4

What is the blood supply to the spinal cord?

Answer 4

two posterior spinal arteries cover the posterior 1/3 of the cord

one anterior spinal artery (dependent on radicular collaterals) covers the anterior 2/3 of the cord

Question 5

What is the artery of Adamkiewicz? Where does it arise?

Answer 5

It is the major radicular collateral supplying the anterior spinal artery

In 75% of people, is arises between T8 and L2

Question 6

What are the types of ascending aortic aneurysm repairs?

Answer 6

Supracoronary tube graft

Wheat procedure: AVR + supracoronary tube graft

Bentall: AVR + aortic root replacement and reimplantation of coronary arteries

David procedure: aortic root replacement and reimplantation of coronary arteries

Question 7

What is the “safe” limit of deep hypothermic circulatory arrest?

Answer 7

30 minutes at 18^oC

50 minutes at 18^oC if antegrade cerebral perfusion is used

Question 8

How is antegrade cerebral perfusion achieved during deep hypothermic circulatory arrest?

Answer 8

cannulating the axillary artery and clamping the proximal portion of the brachiocephalic artery

Question 9

What are the particular anesthetic considerations in open TAA repair?

Answer 9

positioning for left thoracotomy

thoracic epidural placement

spinal drain placement

one-lung ventilation

intraoperative TEE

MEP and SEEP monitoring

Question 10

How can the spinal cord be protected during TAA repair?

Answer 10

left heart bypass (cannular in femoral artery providing antegrade and retrograde flow distal to the crossclamp)

NIOM

CSF pressures < 15 mmHg

mild hypothermia (32^oC)

Question 11

How can the kidneys be protected during TAA repair?

Answer 11

left heart bypass (cannular in femoral artery providing antegrade and retrograde flow distal to the crossclamp)

infusion of cold saline or blood

**guidelines do not support mannitol, furosemide, dopamine or steroids**

Question 12

What happens to venous capacitance with aortic crossclamping?

Answer 12

decreased below the clamp (expels blood from splanchnic system)

increased above the clamp

Question 13

What happens to preload and afterload with aortic crossclamping?

Answer 13

both increase

Question 14

What are the main contributors to hypotension after aortic crossclamp removal?

Answer 14

hypoxia-mediated vasodilatation

accumulated myocardial-depressant metabolites

Question 15

What is the size cut-off for consideration of AAA repair?

Answer 15

> 5.5 cm (treatment of smaller aneurysms does not reduce mortality)

Question 16

Can an epidural be placed prior to AAA repair if the patient will be heparinized?

Answer 16

Yes, if heparin administration will occur as least 1 hour after catheter placement

Question 17

What happens to autoregulation in the presence of carotid artery disease?

Answer 17

it is lost, vessels remian maximally vasodilated

Question 18

At what CBF does ischemia become apparent on EEG? When does neuronal cell death occur?

Answer 18

EEG: 20 mL/min/100 g brain

cell death: 10 mL/min/100 g brain

Question 19

What are the various ways to measure CBF during CEA?

Answer 19

NIRS

EEG

SSEPs

TCD

internal carotid stump pressure

Question 20

What causes reperfusion injury following CEA?

Answer 20

cerebral hemorrhage or edema after carotid flow is re-established because cerebral vessels have lost their ability to autoregulate and are maximally dilated