presentation 2

Aortic arch surgery at the Austin

Two interesting cases in two weeks

Overwhelming at first

2 similar casesboth are young patients, from WA

prior dissecting Type A( ascending aorta) aneurism, repaired in WA

complicated-leak around the graft, pseudo-aneurysm formation along the aorta

otherwise stable

Their Aorta's( rougly)

Why travel from WA?

Experienced surgical, perfusion and

anesthesia team

3 different ways for open thoracic aorta

surgeryTotal deep circulatory arrest-can have bad neurological outcomes

Retrograde blood from (via SVC) to brain while while ascending aorta is open

Antegrade, uninterrupted blood supply to the brain throughout the surgery-very good outcomes

Initial setupInduction, very similar

to cardiac cases Pre medication with morphine, diazepam

Large peripheral iv line.

9 Mac swan-sheath, VIP Pa catheter with continuous cardiac output

4 lumen cvc

methlypredisolone at induction

3 Art lines to monitor circulation

to various parts of the body

Stages of the surgeryPut patient on bypass

Isolate the inominate, left common carotid, left subclavian in a sequential manner, connect them to a graft to supply the brain-antegrade perfusion

Hypothermia and circulatory arrest(for organs below the aortic arch) when aorta is opened

repair of aorta by EVITA graft

Putting patient on bypass

Slightly different from usual

Retrograde perfusion from arterial cannula in right femoral artery

Venous drainage from SVC

both are redo sternotomies-access to heart difficult

ONCE CPB IS ESTABLISHED

The heart is ejecting less blood, making the operating field more accessible

Body temp can be decreased for organ protection

Problems when flow is reversed in an abnormal aorta

flap can block flow

or blood can flow into the pseudoaneurysm

WHEN THAT HAPPENED

then all three art-lines lost their pressure readings and colour doppler of the aorta showed no flow into subclavian artery

decrease venous drainage into pump, allow heart to fill and eject blood normally

ventilate when heart ejecting blood to lungs

once heart started ejecting

centrifugal pump for ante grade

perfusion below arch

Establishing cerebral perfusion

The inominate, left subclavian and right brachiocephalic are ligated and attached to a graft in a sequential manner

Arterial supply to the brain via a side arm from the graft

Brain perfusion always maintained

The vessels are clamped and connected to the graft one at a time

There are numerous collaterals when each vessels is clamped

Once the graft is completely anastomosed, the main pump supplies 10ml/kg of blood to the brain

Graft

graft

Main pump supplying brain

OTHER MEASURES TO PROTECT THE BRAIN

AND DETECT ISCHEAMIA

Cerebral oximetry

another topic by itself....

hypothermia

Thiopenthone

Next.....

Aortic cross clamp in distal arch

Cardioplegia ( custodial) from venous cannula

deep hypothermia

then circulatory arrest below the arch

Followed by opening the aorta

Then actual repair

two devises were used-EVITA stent, and elephant trunk graft

EVITA stent

deployed by a guide wire placed earlier in the femoral artery

Can open up like an umbrella and form a watertight seal at the junction of the pseudoaneurysm

TOE used to confirm if femoral guidewire is in the the true lumen

Issues once aorta is repaired

rewarming 35 C for 20 mins

coming of bypass

dealing with coagulopathy associated with CPB and hypothermia

bleeding

BOTH PATIENTS HAD VERY GOOD POST OP

OUTCOMES