Vascular PP2b Flashcards
aortic cross clamp and spinal ischemia
ways to prevent spinal injury
which patients are at increased risk of spinal injury
maintain perfusion, no hypotension, placement of thoracic epidural or lumbar drain
repeat surgeries, long cross clamp time, clamping above the artery of adamkowitz, hypoperfused patients
what are clamp times for TAA and risk of paraplegia
what are additional methods that can help with spinal surgery
less than 30 min = 10% chance of paraplegia
>30min = 90% paraplegia
epidural cooling, placing a GOTT shunt (between ascending and descending aorta )
name (5) things to prevent spinal cord damange w aortic cross clamping
- location of clamp
- duration of clamp
- GOTT shunt
- ICP <12 w lumbar drain or thoracic epidural
- epidural cooling
AOX and bowel ischemia
where are areas of damange (2)
what to watch postop
ischemia oftern occurs to the inferior mesentary and left colon
dont allow hypotension
watch for postop ilieus
AOX and pulmonary complications
%age that have complications
prevention (3)
pulmonary edema from inflammatory markers and reperfusion injury
30% of AAA patients will have pulmonary complications
prevention: low TV, add PEEP and CPAP, add insentive spirometry
stroke and delirum with AOX
which procedures are high risk
prevention with premeds (2)
from emboli that migrate to brain
higher risk with thoracic and AAA repairs
continue to take anti plt drugs, a fib drugs,
TAA: reasons they occur
symptoms
when to have surgery
most 80% are from atherosclerosis, then trauma, aortic dissection and connective tissue disorder (marfans)
tearing pain the chest, back pain, CAD, COPD
AAA > 5.5cm
TAA > 6.5 cm
DAA > 6.0cm
how do we categorizes TAAA
which is the most popular category
Debakey: Type I, II, III
I: ascending aortic tear down entire aorta
II: tear located only in ascending aorta
III: tear is from thoracic to abdominal
Crawford: Type I - IV. type II and III are most difficult to repair. type II at most risk for paraplegia
I: DT and UAA
II: DT and most AA
III: LT and most AA
IV: most AA
Standford: Type A or Type B. Is the ascending aorta involved yes(A) or no (B)
discuss crawford
which are hardest to fix
which is most at risk for paraplegia
Crawford: Type I - IV. type II and III are most difficult to repair. type II at most risk for paraplegia
I: DT and UAA
II: DT and most AA
III: LT and most AA
IV: most AA
Debakey AAA categories
discuss
Debakey: Type I, II, III
I: ascending aortic tear down entire aorta
II: tear located only in ascending aorta
III: tear is from thoracic to abdominal
what are some big risks with AAA and TAA
spinal cord perfusion: artery of adamkowitz and paraplegia
renal perfusion: 30%
pulmonary complications: 50%
overall mortality is 14%
how to prepare of TAA
aline placed where, why
what is a routine procedure
2 large bore IVs, Aline, blood tubing, lots of PRBcs, FFP, platlets (15u)
Aline R radial, proximal to clamp
+- PA cath, CVP pressure
TEE is routine
intraop monitors
add a fem line?
could be measuring SSEP or MEPS
if clamp placed high on descending aorta, want to measure BP to kidneys, other organs, and lower extremety
may use a DLT
TAA induction - emergence
who stays intubated
want smooth, no bucking no coughing, no swings of HTN (aneurysm rupture)
balance anesthesia technique w SSEP or MEP monitoring
extubate in the OR
given alot of blood products, on multiple pressors, clamp time longer than 30 min, pulm edema
why would a TAA patient be coagulopathic after surgery (4)
what are intraop labs for TAA
- hemodilution from blood products
- liver dysfunction from decrease perfusion on clamp time
- hypothermic
- residual heparin in system
ACT, ABG, Glucose, coags, renal labs,
how to treat and emergency aneurysm rupture
what to secure an airway as quickly as possible and make patient hypotensive MAP 50s for a brief period of time. after ETT placement, extra IVs, A line, central line.
then maintain map, add pressors, give blood products,
normothermia
grab TEE to assess filling pressure and ventricular function
EVAR
benefits of this procedure
disadvantages
benefits: less invasive, faster recovery, less pain, less bleeding, less CV complications, better 30 day mortality,acoiding ischemia from long cross clamp times
Cons: expensive, no change in 2-3 year mortality, can have leaks, 23 min fluroscopy and 132 mls of contrast
what is the technique for stent placement
look at preop images, bilateral groin incisions, supine, deploy stent
what type of anesthesia for EVAR
which is superior and why
when to use general
treat pain
mainttain BP
invasive lines
bleeding
MAC w regional or GETA
MAC w regional is superior. Regional provides: increased blood flow,
GETA w descending aortic repairs
pain treated with fentanyl 2mcg/kg
esmolol, NTG, phenyl, Levo
A line, +- CVP PA cath
can have large blood loss, have extra IV and blood tubing ready
during an EVAR what is the critical stage
what do you want BP at this stage
deployment of stent
want to give heparin 5000u, ACT >200
ask patient to hold their breath and give apnea
mild hypotension, have greater control when placing stent
why would you have to convert to open with EVAR
what to prepare for
misdeployment, reputure of iliacm aneurysm rupture, increase bleeding
intubate quickly, open fluids, assess bleeding (rate, cuase, how much control?), give pressors
discuss the 5 types of endo leaks
which are emergencies ****
I- V
I high flow around the stent ****
II low flow, branches of arterial stents
III: leaking from the stent itself *****
IV: stent is porise and sweating, will correct after reversal
V: due to pressure, not detectable
EVAR: why can spinal and renal injuries occur
spinal: from plaque rupture and emboli or converting to open and decreased perfusion
renal: complication from the 132mls of contrast
post implantation complications from EVAR
- stent can migrate and occlude renal and mesenteric arteries
- infection: increase WBC, fever, incresae CRP
- rupture and hemorrage
anatomy of lower extrem for vasc surgery
T12 suprarenal
L1 SMA infrarenal
L3 IMA
L5: iliac arteries
