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Abdominal Ao and LE Aneurysms yrs later (4.5% vs. almost 10%). It‘s very cost At 6 yrs, both groups had comparable survival
efficient. Thus, we should screen for AAA in men. rates (64%) (if died, from any cause, not just
Definitions: rupture)
Aneurysms: permanent localized dilation, diam Expansion rate Thus, if aneurysm 50% of expected nl About 10% diameter ↑ in diameter / yr have to treat it
Ectasia: dilation 50% of nl o Rapid growth increased rupture risk o If 4-5.5 cm diam, annual risk for
Median expansion rate = 3^(0.106t) rupture is 2.2% / yr
Epi: o But this rate is higher with the
M:F ratio 5-7:1 (so M>F) Rupture following RFs
Prevalence Diameter is the primary determinant RF for F
o AAA > 3 cm : 3-10% for pts > 50 yo rupture Larger initial diam
o AAA > 3 cm : 4-6% for VA pts bw 50- LaPlace: T=Pr/h Current smoking
79 yo o 4 cm: 1.4% o 4-5 cm 0.5-5% Higher BP
3.5 Caucasian: 1 AA o 5-6 3-5%
Seasonal: Fall, winter o 6-7 10-20% Risk fo rupture of Larger (>5.5 cm) aneurysms
Present in 6% of CAD pts, 9% PAD pts, 50% o 7-8 20-40 Lancet (2002): 198 vets w/ AAA >5.5 cm who
of pts w/ femoral or popliteal aneurysms o >8 30-50 refused /unfit for surg
Location: 95% of arterial aneurysms in Al RFs Mean f/u 1.52 yrs showed 112 deaths, 45 from
o 95% of Ao aneurysms are infrarenal o HTN ―probable‖ AAA ruptures
o Thrombosis, embolism can occur but o COPD Found that diam was correlated w/ risk for
rupture is more common o Smoking – strong RF rupture per yr
Ruptured AAA: 13 leading cause of death
th o FHx o 5.5-5.9 cm 9.4%
(USA) o Shape/wall tension: (saccular/bowing o 6-6.9 10.2
out = high risk; fusisform lwr risk) o >7 32.5
Diagnosis o Thrombus Anything >7 is considered very large
directed PE is accurate if abd growth 15 mm
o plain abn x-rays Good results: > that of open surg
the prosthesis but within the aneurysm sac U/S
not an aneurysm Counseling your pts: Rate of rupture w/ observation of sm
Classification Types: Open AAA surg is appropriate for fairly healthy aneurysms: ~2%/yr
o I: attachment site leak pts w/ AAA‘s >5.5 cm Endovasc aneurysm repair is an option for
IA: prx end Not indicated in pts w/ chronic fatal dz: severe ~60% of pts
IB: distal end COPD, CHF, cancer Mortality lwr for endovasc repair than open
o II: branch leak- retrograde blood Problematic in ―healthy‖ elderly (>80 yo) surg
Most AAA are silent
comes from mesenteric a or collaterals Long term outcomes for endovasc repair similar
IIA: simple (1 branch) Primary role of AAA repair: prevent rupture to open surg
IIB: complx (2+ branches) Poorer risk pts more likely to develop but endo vasc repair is more $$$ and requires
o III: Device defect functional impairment after open surg indefinite monitoring due to higher re-
IIIA: junction leak intervention rate (10-20%)
IIIB: fabric disruption Popliteal aueurysms
o IV: Fabric porosity Much less common Predisposing conditions
o 1% of 65-85 yo M pts Marfans: fibrillin plays greater role in
What connects IMA to SMA? o present in 2-3% of AAA pts upper/thoracic Ao; collagen plays bigger role in
1. Marginal artery of Drummond o but 40-50% of pts w/ popliteal lower/abdominal Ao
(collection of arcades) and aueurysms also have Ao ones o so Marfan‘s pts have defects in
2. Arc of Riolan (meandering mesenteric a) Clinical pres ascending Ao
(more variable). o Most silent Ehlers Danlos
Coils can be placed in these to prevent type II o Thromboembolism – the knee bends a o Spont arterial rupture w/o necessarily
endoleaks lot which can break off emboli having aneurysms
o Large (4 cm) ones may cause Lowes Deeps (?) syndrome
Trial comparing conventional and endovascular compression o Defect assoc‘d w/ premature aneurysm
repair of AAAs o Rarely rupture formation
Lancet (2004) (EVAR Trial): For pts with >5.5
diam AAA, underwent open surgery or Repair of Popliteal aneurysm Gallbladder and Pancreas
endovascular repair Indications Gallbladder anatomy…tricky ones: Spiral valves of
30 day mortality (all-cause) o Symptomatic Heister and Triangle of Calot
o Open surg: 4.7% o 2 cm diam generally
o Endovasc: 1.7% o Intraluminal thrombus Bile formation:
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liver excretes bile continuously, 500-1000 mL / LFTs for Tbili, AST, ALT, AP Hepatobiliary Radionuclide Scanning (HIDA
day ↑ WBC may indicate cholecystitis scan)
w/ intact Sphincter of Oddi, bile flow is ↑ TBili and AP suspicious for o Nuclear med study
directed into gallbladder choledocholithiasis o T-99 labeled protein injected IV, taken up
bile composition: water, e-lytes, bile salts, ↑ bili, AP, and transaminases in cholangitis by Kupffer cells of liver, excreted by bile
protein, lipid, pigments o Scarred/ inflamed GB (cholecystitis) will
Enterohepatic circ: Ways to evaluate the GB show the Technetium never taken up by the
o 80% bile salts reabsorbed in terminal U/S GB, never ends up in duodenum
ileum o Gen info Magnetic Resonance
o 15% reabsorbed by colon Non-invasive, painless, no Cholangiopancreatography (MRCP)
o 5% excreted by stool radiation o Typically used for pts w/ GB/BD/head of
Operator/technician dependent pancreas cancers to assess invasion of
Gallbladder (GB) fxn Demonstrates gallstones w/ 90% vasculature
GB stores 80% of bile secreted by the liver sens and spec o 95% sens, 89% spc for choledocholithiasis
GB mucosa reabsorbs Na, Cl, water o Cholelithiasis: stones in GB o Single, non-invasive test for the dx of
concentrating bile 10x o Choledocholithiasis: stones in CBD. biliary and pancreatic dz
Releases bile in response to hormones: Secondary sign = Biliary ductal dilatation
o (+) CCK, vagal stim‘n, distension of (proximal dilatation, distal stricture) Gallstone Dz
gastric antrum o Acute cholecystitis: GB wall thickening, Gallstone Formation
o (-) VIP, splanchnic symp stim‘n, pericholecystic fluid (edema around GB), Formed from solids settling out of bile soln in
somatostatin sonographic Murphy‘s sign (+ Murphy as a the GB: bili, bile salts, phospholipids,
result of pressure from U/S probe) cholesterol
Sphincter of Oddi o Chronic cholecystitis: contracted, thin- Cholesterol stones 80%, pigmented stones 15-
1. Regs flow of bile and pancreatic enzymes into walled GB 20% (Western world)
duod Intraoperative Cholangiogram –
2. prevents regurg of duod‘l contents into biliary o Gen info: to confirm there are no stones, Epi and Nat Hx
tree you need Autopsy studies show prev of cholelithiasis 11-
3. diverts bile into the GB, resting pressure 13 torr go through cystic duct 36% so gallstones are common
4. CCK causes sphincter relax‘n and GB Filling of R and L hepatic ducts RFs: Female, age, obesity, pregnancy, gastric
contraction in response to acid, fat, amino acids Absence of filling defects in CBD bypass surg, term ilium resection, diet,
in the duod tells you there are no stones hereditary spherocytosis, sickle cell dz
5. morphine sulfate can cause Sphincter of Oddi Free flow of contrast into duod Comps
spasm (causes RUQ tenderness so don‘t give Endoscopic Retrograde o Acute cholecystitis
someone with biliary colic morphine) Cholangiopancreatography (ERCP) o Choledocholithiasis (stone in CBD) +/-
6. Glucagon relaxes Oddi – can help when have o Performed by gastroenterologist, use cholangitis (infxn of extrahepatic biliary
trouble getting contrast through endoscope to cannulate the CBD ducts)
o Can perform retrograde sphincterotomy o Gallstone pancreatitis
Labs (cut Oddi, let stones come out) o Cholecystoduodenal fistula +/- gallstone
get CBC for wbc, hct, hbg, platelets o 5% complication rate-- Complications ileus (gallstone so big, size of golf ball,
include perforation and pancreatitis causes scaring and fistula through which it
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goes through to duodenum, small intestine, PE Rare, aggressive tumor w/ poor prognosis (5 yr
gets trapped in ileocecal valve ) o Scleral icterus survival = 5%)
Symptomatic gallstone dz develops in 3% of o Mild tenderness epigastrum, RUQ Calcified ―porcelain‖ GB (stiff, hard) = 20%
asymptomatic pts / yr Dx malignancy. 80-90% of adenocarcinomas
Complicated gallstone dz develops in 3-5% of o RUQ u/s choledocholithiasis, dilated Corvoisier’s sign: enlarged, palpable GB
symptomatic pts / yr CBD (proximal to obstruction, >8 mm) Found incidentally in 1% of pts undergoing
o MRCP / ERCP cholecystectomy for gallstones
Chronic Cholecystitis o Hi bili, AP (bile ducts are irritated; bile
Repeated inflammation of GB (biliary colic) Cholangiocarcinoma – cancer of extrahepatic
ductal tissue produces AP), transaminases
Tx – both these methods are done: billiary ducts
Acute Cholecystitis o ERCP sphincterotomy, stone extraction rare, most often at hepatic duct bifurcation
Obstruction (usu stone) causes cystic duct o Laparoscopic cholecystectomy (Klatskin tumor)
inflamm‘n GB distention, inflamm‘n, secondary Survival unresectable dz: 5-8 mo, 5-yr survival
bac infxn (due to stasis) Cholangitis – typical comp of stones stuck in CBD, resected dz 10-30% (poor prognosis)
Presentation stasis ascending bacterial infxn, usu gm (-) and RFs: primary sclerosiing cholangitis,
o RUQ/epigastric pain, lasting 1-2 days anaerobes choledochal cysts, UC, Clonarchis
o Not hungry
o N/V Presentation Three Rules of Surgery!
o +/- Fever o Charcot‘s triad: F, RUQ pain, jaundice 1. Eat when you can!
PE o Raynaud‘s pentad: above + septic shock + 2. Sleep when you can!
o Focal tenderness in RUQ MS change 3. Don‘t mess w/ the pancreas
o Palpable mass sometimes PE
o + Murphy‘s o Febrile, focal tenderness and guarding RUQ ANESTHESIA – Dr. Ken Abbey
Dx Dx
o RUQ U/S stones in GB, GB wall o RUQ u/s choledocholithiasis, dilated Case: hernia repair for Al
thickening, edema, sonographic Murphy‘s biliary ducts Al = 46 yo shoe salesman married to Peg
sign o ERCP gold standard visualization. Do HPI: was swuatting to fit a shoe, felt pop in
o HIDA scan non-visualization of GB this right away – stones must be removed groin
Mild leukocytosis (12-15,000) +/- mildly ↑ quickly PMH: low IQ, low self esteem
LFTs o Elevated bili, AP, LFTs; leukocytosis PSH: removal of ‗will to live‘ by Peg
Tx Tx
o IV fluids, pain control, IV Abx (3rd gen o IV abx, fluids, ICU admission, vasopressor You speak to surgeon, Brett, who asks:
cephs), remove GB w/in 24 hrs typically support what are the 4 goals of anesthesia?
o Emergent biliary decompression by ERCP, o Amnestic - you don‘t remember
Choledocholithiasis – stuck in CBD, so no bile eventual GB removal o Hypnotic – you‘re not aware
passes from liver to small bowel o Analgesic - not in pain
Laparoscopic Cholecystectomy (Lap Chole) video o Paralyzed - not moving
Pres What does MAC mean?
o RUQ / epigastric pain Billiary neoplasms - rare o Minimum alveolar concentration
o N/V GB carcinoma
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o Amt of anesthetic necessary to prevent If adult, then give muscle relaxant (ie
movement in 50% of pts on incision pancuronium) before intubation (cords won‘t Opiates:
o We aim for 1.3 MACs (95% of rats don‘t slam together, helps give good view w/ Morphine
move) Laryngoscope) Hydrocodone
Caution w/ morbidly obese pts: if give m Methadone
So, why do we do anesthesia? relaxant, may then be in a position where you Fentanyl
From 1821-46, MGH only did ~1 surgery per can‘t intubate and cannot ventilate either Dilaudid
month (no anesthesia) disaster Alfentanyl (short acting, quick onset)
So a good surgeon back in those days was one Pre-oxygenation buys you 6-7 mins in healthy Remfentanyl – spontaneously metabolizes,
who was fast (30 seconds chop off leg!) young pt good when need quick pain relief that quickly
o Decreases oxygen demand goes away, ie head/neck cases
Gas is an anesthetic, meets all 4 goals. o When anesthetized, O2 demand goes down
Used sometimes in kids to 200 cc/min Work on mu receptors
o If you are not hooked up to O2 and you are Reversible w/ Narcan
Midazolam (Versed) = benzo, anxiolytic, amnestic apneic, the O2 gets taken from the lung
so don‘t talk to pt until 1 hr after surgery; reservoir (FRC, what passively stays in Propofol
otherwise they won‘t remember lung after passive expiration) O/D killed Michael Jackson – they couldn‘t
o Pre-oxygenation causes FI02 increase from manage his airway
Fentanyl = opioid, 100x more potent than 0.21 to 1 MOA: GABA-A and Na channel
morphine, given in micrograms, initially acts like o Thus when you are doing intubation, slow
Effects
short acting drug (lipophilic; sudden onset), then down. o Euphoria
redistributes to fat. Initial effects go away fast. If o However, caution w/ obese pts, they o Hypnosis
give a lot, Vd fills up and acts like long-acting. decompensate faster. With obese pts, after o Amnesia
Cheap as dirt. Very little S/Es. Risky to use b/c of giving benzo, fentanyl, and propofol, o CV
sudden onset of action. ventilate before intubation to determine if o Resp
ventilation is even possible. Then give o V little analgesia
Propofol – common induction agent muscle relaxant o Not reversible
other induction agents = gas induction (ceba- Which pts do you give m relaxant right away?
fluorine, least stinky), ketamine, penthol o ―Rapid sequence induction‖ in ppl who Suggestion: use Versed instead of Propofol. And
(penafol, potent barbiturate, tastes like garlic d/t are aspiration risk (full stomach, bad have Narcan in your pocket.
sulfa groups), midaz, other barbituates reflux)
(methahexatol), ECT o If try to ventilate while pushing air in Vecuronium = non-depolarizing m relaxant.
Propofol used a lot bc rapidly distributes and stomach, they may aspirate. Therefore they Competitive inhibitor of NMJ. Won‘t cause
causes least nausea get propofol then m relaxant right away fasiculations.
Downside = burns upon injection
Cheapish: $6 a vial Are benzos reversible? Yes Succinocholine = depolarizing (2 Ach‘s stuck
Flumazenil = benzo antagonist. together), causes NMJ to be depolarized. All
Sequence: Benzo Fentanyl Propofol o If pt is a drinker, may cause pt to… wake muscles fire, always wake up sore. After firing,
Propofol will cause apnea up? (not sure what he said)
o Works on NMDA receptors
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muscles have refractory period of 6-10 mins. Bacterial, fungal o Lower specificity (detects only 60% of
Advantages = quick onset, short duration. o Inflammatory abdominal aortic AAAs)
Why doesn‘t heart stop? Pathophys Abd U/S
it‘s smooth muscle Chronic transmural infamm‘n good screening tool (#1)
gut, heart, vasculature—all smooth m, still Destructive remodeling of extracell‘r matrix v sens and spec
work Depletion of vascular SM cells accuracy 80-90%
ppl stop breathing bc diaphragm is skeletal m Redistribution of hemodynamic stresses of cost effective
vessel wall can detect AAA in their earliest stages
How about BP and CO? Reduction of collagen and elastin content from reproducible to within 0.3 cm
Propofol = potent vasodilator, so is gas proximal to distal aorta Difficulties
That‘s why BP goes down o Loss of elastin dilatation and aneurysm o Bowel gas interference
o Must give fluids bc capacitance has o Loss of collagen rupture o Obese pts
increased (due to vasodilation) 58% decrease in elastin from suprarenal to o Suprarenal and iliacs not well visualized
o This increases preload infrarenal aorta o Operator dependent
o Starling: fixing preload increases BP Elastin T ½ 40-70 yrs, not synthesized
Scopolamine can be used to reduce awareness Genetics: 15% with +FHx CT Scan
in trauma pts w/ less lowering of BP Most accurate
RFs Gold standard as preop scanning tool
ANEURYSMAL DISEASE – Mitchell Number one: age (>65) Excludes rupture in symptomatic pts
Male Defines anatomy and anomalies
Def: ―a widening” 1.5x normal size Cig smoking Reproducible to within 0.2 cm. Use 2 mm cuts
o Ectasia= dilation 5-5.5 cm if repair
common) Reproducible to within 0.2 cm
abdominal girth 0.5 cm in 6 mo then it should be
o visceral / extremity ischemia thickness repaired
o juxtarenal and suprarenal AAA COPD: mechanism ↑ imbalance in protease No evidence to support regular medical mgt to
o Horseshow kidney activity prevent expansion
o Renal insuf w/ uncomtrolled HTN Eccentric saccular aneurysm—increases risk
o generally, not used often Rapid expansion Types of Repair
Inflammatory: no increase in risk Endovasc aneurysm repair (EVAR)
AAA Nat Hx Open anerysmorrhaphy
Grows avg 0.4 cm / yr Screening o Midline transabdominal incision
Risk of rupture exponentially related to Everyone agrees: o Retroperitoneal appraoach
aneurysm of diam M >65 yo with hx of smoking
5 cm diam avg yrly rupture rate 3-5% More controversial: EVAR Advantages
7 cm diam carries rupture rate of 19%/yr o Men >65 yo, FHx of AAA, females w/ mult Reduces operating time
RFs Shorter LOS and ICU stay
Complication of AAA ↓ recovery time, post-op pain
Rupture Mgmt depends on: Blood transfusion
o only 40-50% reach hosp alive (15:13) Size Less chance graft infxn
o 505 operative mortality o Good risk pts w/ AAA > 5.5 cm should Return to work faste
o Overall >75% mortality rate for repair undergo elective repair
o Clinical pres o No survival advantage for 5.5 cm) or US surveillance every 6 Probs of endoleaks, graft failures
Distal embolization mo Require life long graft surveillance
o Most minor affecting distal extremities/toes o 4.9 yr f/u found surgery mortality 25%,
Long-term reports not available
o More common during repair surveillance mortality 21.5
No difference in mortality
Aortocaval fistula o Most deaths d/t cardiovascular dz
o Rare o Median AAA growth rate 0.33 cm/yr
Based on avail evidence, EVAR is appropriate tx
o Pres o Bottom line: no level 1 evidence to repair
for selected pts, esp those w/ hi risk for open surg
LE edema, hematuria, rectal bleed AAA 75 yo
thrombotic dz
rupture o Disabling COPD, home O2, FEV1 2 yrs
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Young pts – good operative risk?? o 15 mm length glues); or open conversion if all
EVAR: Preop imaging o 25 mm seal zone persist >6 mo
o +/- contrast Extent of aortic and iliac a involvement - only worry about surg
o Need lrg volume of iodinated contrast (100- o Stent graft usu ends in common iliac a intervention if aneurism sac
150 cc) o If diam of common iliac too large, the stent continues to grow – treat w/
o Narrow collimation, 3 mm cuts can be extended to the external iliac a embolization, lap clipping
o Reformatting fo axial slices 3D o You may exclude flow from mesenteric o Late comps
reconstruction arteries which will cause sigmoid ischemia Graft limb thrombosis – kinking in
Pitfalls o The hypogastric a should be coil-embolized limb
o As AAA expands and lengthens, the neck as retrograde flow from the internal iliac a Stent-graft infxn: no published
deviates anteriorly and laterally can will cause an endoleak reports, only anecdotal reports
overestimate neck diam and Comps Device failure
underestimate neck lengh o Perioperative Dilatation ofproximal neck
Injury to access vessels Late rupture
Angiography Embolization
not necessary for graft sizing - Microembolization and death EVAR results – a bunch of stuff she skipped
can provide add‘l info from renal failure
o grade of stenosis of branches of Ao - Distal ischemia EVAR: Post-op surveillance
o renal, accessory renal Post-implant syndrome o What to look for in the post op period
o patency of IMA - Febris eci (40 deg C) Change in aneurysm size (ie
o lumbars - Depression continued growth = bad)
- Back pain from thrombosis Stent migration
EVAR Anatomical Requirements - Incidence 150% Endoleak
Groin and wound comps Limb stenosis
Visceral supply
o Endoleak – failure to exclude aneurysm Device integrity
o Access patency celiac and SMA before pt
sack from arterial blood flow o CTA
IMA overstented
Type 1: attachment to site leaks 98% accurate in detecting
Diameter, length, angulation, and conical nature
Type 2: branch leaks endoleaks
of prox neck
Type 3: structural failure Accurate and reproducible diameter
Calcification and mural thrombus in prox neck measurements
Type 4: Graft wall porosity
Diam of iliac a Dense contrast bolus and delayed
Type 5: endotension
Length of distal sealing zone o Management of endoleaks images
Tortuosity of iliac aa Type 1 and 3 Time course: 1, 6, 12 months, and
Extent of aortic and iliac a involvement - Require immediate repair: yearly thereafter
Neck: use cuff or extension grafts; 2 kinds of open repair
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Midline Retroperitoneal to maintain perfusion to pelvis and sigmoid one o #1 cause of periop mortality
- explore abdominal - hostile abdomen must maintain blood supply – may need to hook o Renal failure
viscera - stromas up the IMA Distal embolism
- expose distal common - morbid obesity Indications for renal a reconstruction Severe acidosis – can be from prolonged aortic
iliac a: lrg right iliac a - aneurysm requiring o Renal a aneurysm >2 cm diam clamping, can get severe hypoTN w/ release of
aneurysm suprarenal clamping: o Involvement of renal a ostia clamp
- right renal a dz not complex aneurysm w/ o Renal failure w/ bilat pre-occlusive renal a Graft infxn – rare, increased incidence after
amenable to celiac and sma vessel dz o Asymptomatic >80% renal a stenosis assoc‘d ischemic colitis
endarterectomy or juxta/suprarenal AAA o Renovascular HTN Ischemic colitis – most dreaded complication
- L sided vena cava - horseshoe kidney o Best approached via retroperitoneal o Occurs ~10%, more common in setting of
-inflammatory AAA approach rupture
o Only 2-3% clinically significant
Retroperitoneal approach Ruptured AAA o Usu 2-3 days post op
o We are on the L side of the abd, sneak If aneurysm freely ruptures anteriorly into o Clinical manifestations
behind peritoneum down to the Ao which peritoneal cavity, rapid exsanguination Unexplained fluid sequestration
lies over the lumbar spine occurs—pt usu doesn’t make it to hospital (BP unresponsive to resuscitation
o Advantages: If it ruptures posteriorly, the hemorrhage goes b/c their colon is dead)
you can get higher up on the Aorta into retroperitoneal space, may be contained, pt Fever, leukocytosis, sepsis (L colon
than midline approach (in midline makes it to the ER bc it’s a controlled bleed – dies bc insuff blood supply bc
approach, pancreas gets in the way) there‘s no where for the blood to go you‘ve taken out the IMA)
easier w/ morbidly obese pts Achieve rapid proximal control by compression o Prevention: reimplant IMA if
Midline: the peritoneum is opened, make long or clamping of supraceliac Ao through the Lrg IMA
incision down to pelvis diaphragmatic crura Good back bleeding
After establishing control, move clamp to Stump pressure <40 torr
Techniques of open repair: (she went through a infrarenal position h/o L hemicolectomy
bunch of diagrams w/ relatively little explanation,
this is what I could catch) Goals of AAA repair Late comps
move renal veins out of the way; give pt Prevention of death from rupture Aortic graft infxns
heparin; apply clips above and below the Limb preservation by maintainance of adequate o 1% aortoiliac
aneurysm arterial perfusion o 2% aortofemoral
―oversew‖ lumbar arteries Maintaining quality of life – minimize comps, o 70-80% late
Cut a ―button‖ of tissue and sew it onto the maximize durability of reconstruction, o usu staph aureus, pseudoaneurysms in
graft preservation of sexual fxn (parasympathetic anastomotic suture line ie almost always
sew aneurysm sack closed to prevent intestines plexus responsible for ejaculation) from graft infxn
from sticking
tube graft = a straight shaft of graft Early comps of AAA Repair (End of lecture)
bifurcated graft = aneurysm extends into iliac bleeding – massive transfusion increases post
aa op M&M
MI
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