Anesthesia for vascular surgery 4

Question 1

Thoracic aortic aneurysms are associated with

Answer 1

Marfan syndrome
Ehlers-Danlos syndrome
bicuspid aortic valve & nonsyndromic familial aortic dissection

Question 2

The repair approach for thoracic aortic aneurysms includes

Answer 2

descending aorta- left posterolateral thoracotomy, OLV
ascending aorta- supine, median sternotomy
full or partial CBP

Question 3

Thoracoabdominal aortic surgery considerations innclude

Answer 3

OLV, extracorpeal circulatory support including circulatory arrest, renal & spinal cord protection, induced hypothermia, invasive hemodynamic monitoring, massive transfusion, and management of coagulopathy

Question 4

The typical presenting symptom of thoracic aortic dissection is

Answer 4

acute, severe sharp pain in the anterior chest, the neck or between the shoulder blades
-diminution or absence of peripheral pulses

Question 5

Signs & symptoms of thoracic aortic aneurysms typically reflect

Answer 5

impingement of the aneurysm on adjacet structures
hoarseness results from stretching of the left RLN
stridor is due to compression of trachea
dysphagia is due to compression of the esophagus
dyspnea results from compression of the lungs
edema from compression of the superior vena cava

Question 6

The Crawford classification of TAA includes

Answer 6

Type I- aneurysm involving descending thoracic & upper abdominal aorta
Type II- descending thoracic and most abdominal aorta
Type III- lower thoracic aorta & most abdominal aorta
Type IV- most or all abdominal aorta

Question 7

Describe the DeBakey classification dissecting aortic aneurysms

Answer 7

type I- ascending aortic tear with dissection down entire aorta
type II- tear in ascending aorta with dissection limited to ascending aorta
type III- tear in proximal descending thoracic aorta with dissection from thoraci aorta to abdominal aorta

Question 8

TAA morbidity & mortality is similar to

Answer 8

AAA with increased risk in every category**

-pulm complications, renal failure, paraplegia

Question 9

The spinal cord receives its blood supply from

Answer 9

two posterior arteries** and one* anterior spinal artery

Question 10

The largest of the radicular arteries is called the great radicular artery or

Answer 10

artery of Adamkiewicz**

provides major blood supply to the lower two thirds of the spinal cord

Question 11

Anterior spinal artery syndrome can result in

Answer 11

flaccid paralysis of the lower extremities and bowel & bladder dysfunction
sensation & proprioception are spared

Question 12

Spinal cord protection includes

Answer 12

limit cross clamp time <30 minutes
distal aortic perfusion (extracorporeal support)
CSF drainage
intrathecal papaverine
mild hypothermia
barbiturates, corticosteroids & avoid hyperglycemia

Question 13

SSEPs are used to monitor

Answer 13

posterior/lateral cord, sensory

Question 14

MEPs are used to monitor

Answer 14

anterior cord, motor

cannot use muscle relaxation

Question 15

TAA preop prep includes

Answer 15

need to know extent of aneurysm, technique of repair, plans for distal aortic perfusion
PRBC (15u), FFP (15 u), & platelets

Question 16

Monitoring for TAA includes

Answer 16

A-line- right radial b/c cross clamp may be placed proximal to the left subclavian artery occluding flow
Right femoral artery cath placed to monitor BP distal to clamp when clamps are high on deescending aorta & lower body is perfused by bypass
\+/- PA catheter
\+/- CSF pressure
IV access
TEE routine
body temp
SSEPs & MEPs

Question 17

Describe positioning for TAA

Answer 17

thoracoabdominal incision & retroperitoneal dissection

Question 18

When no bypass is used for TAA, clamp time of

Answer 18

<30 minutes are associated with 0-10% paraplegia
-epidural cooling
regional hypothermia (renal protection)
in-line mesenteric shunting

Question 19

The anesthesia technique for TAA includes

Answer 19

slow & controlled induction to avoid aneurysm rupture
usually a balanced anesthetic- opioid, low dose volatile agent, benzos, & NDMR
TIVA if MEP monitoirng
combine epidural/GA (hypotension can be an issue)
+/- thoracic epidural for pain
extubate in the ICU

Question 20

If a TAA has involved ________ you can consider extubation in the OR (need control of emergence hemodynamics)

Answer 20

limited blood loss, edema, & ventilation is adequate

Question 21

Coagulation may occur during TAA as a result of

Answer 21

dilutional coagulopathy during massive transfusion
residual heparin
ischemia of the liver
persistent hypothermia

Question 22

Emergent ruptured aneurysm care includes

Answer 22

14 G IVs in most accessible location
awake intubation vs. RSI with 0.1 mg/kg etomidate
open- surgeon should be preparing to clamp the aorta at the same time as induction
PRBCs, RSI, normothemic if possible
dopamine, epi, norepi, and vasopressin if needed
after aorta clamped and hemodynamics restored then worry about placing art line, CVP, PA, etc.
TEE recommended for assessment of ventricular function, filling pressures