requirements obtained from the blood bank but usually 2 to 4 units of packed red blood cells are

sufficient. A thorough peripheral pulse examination should be included in the physical examination and

validated with formal ankle–brachial indices. The anesthesiologist should see the patients

preoperatively. In addition, patients should be started on an aspirin and a statin (HMG Co-A reductase

inhibitors) and consideration made for starting a beta-blocker if they are not already on them. The

ACC/AHA Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery

recommend that the beta-blockers are “probably recommended” for vascular surgery patients who are

at high cardiac risk or those with more than one clinical risk factor (risk factors – CAD, CHF, CVOD,

DM, CRI).167 However, much of the data that this recommendation was based upon have been

questioned due to reports of unscrupulous academic behavior by the investigators, and many now

believe that initiation of beta-blockers before major vascular surgery is unwarranted and potentially

harmful.168

Furthermore, the ACC/AHA Guidelines recommend that patients undergoing vascular surgery should

be on a statin. Notably, a recent study demonstrated that statins were associated with a decreased

incidence of perioperative mortality and nonfatal myocardial infarction after aneurysm repair.169

Indeed, all patients with atherosclerotic cardiovascular disease should likely be on aspirin, a statin

medication, and an ACE inhibitor long-term as part of the AHA/ACC Guidelines for Preventing Heart

Attack and Death in Patients with Atherosclerotic Cardiovascular Disease.170

All active medical problems, including abnormalities identified during the preoperative evaluation,

should be controlled as well as possible before elective aneurysm repair. However, extensive diagnostic

testing is probably unnecessary. Routine pulmonary function tests and measurement of arterial blood

gases are not indicated, although they may be beneficial in selected patients with advanced chronic

obstructive pulmonary disease.171 The presence of chronic obstructive pulmonary disease often

complicates postoperative ventilator management, but it is unusual for a patient’s pulmonary disease to

be sufficiently severe to preclude operation.172 Similarly, timed urine collections for creatinine

clearance and other assessments of renal function have not proved beneficial despite the dramatic

impact of preoperative renal insufficiency on perioperative outcome although it may be beneficial to

calculate the estimated glomerular filtration rate.

The appropriate cardiac work-up before AAA repair is evolving and is somewhat institutiondependent. This controversy has been further complicated by the publication of the CARP Trial that

examined the role of coronary artery revascularization before major vascular surgery among patients

with significant coronary artery disease.173 Notably, the study reported that preoperative coronary

artery revascularization did not reduce the incidence of either perioperative myocardial infarction or

long-term mortality. It is important to emphasize that the overall objective of the preoperative cardiac

work-up is to optimize the cardiovascular system and thereby reduce both the perioperative and longterm risk of myocardial infarction and death. Admittedly, the prevalence of coronary artery disease

among patients undergoing AAA repair is quite high. Hertzer et al.,174 in a landmark publication,

reported that 25% of 1,000 patients undergoing evaluation for peripheral vascular surgery (cerebral

vascular occlusive disease, lower extremity arterial occlusive disease, AAA) had severe, surgically

correctable lesions detected during cardiac catheterization; 6% had severe, uncorrectable disease, and

only 8% had no evidence of disease. Interestingly, the incidence of surgically correctable disease was

highest among patients undergoing evaluation for AAA. The most recent edition of the ACC/AHA

Guidelines hase simplified the preoperative evaluation before elective vascular procedures.167,175

Briefly, patients with active cardiac conditions (unstable coronary syndromes, decompensated

congestive heart failure, significant arrhythmias, and significant valvular disease) should be seen in

consultation by a Cardiologist. Patients with good functional capacity as defined by the ability to

generate at least four metabolic equivalents (METS, 4 METS – ability to walk up a flight of stairs) can

undergo major vascular procedures without additional testing. Those patients that cannot generate 4

METS and have at least 3 clinical risk factors (see above) should be considered for further cardiac

testing if the results will change the clinical management. Notably, there is insufficient evidence to

support a reduced cardiac work-up for patients undergoing endovascular repair.176 It is important to

emphasize that although the cardiac risk of endovascular repair may be less, the subset of patients

undergoing the procedure are often older and sicker.

All patients should undergo some type of imaging modality as part of their preoperative evaluation to

confirm the diagnosis and plan the procedure. Indeed, determining whether a patient is an endovascular

candidate and appropriately sizing the device depend on the anatomic measurements obtained at the

time of imaging. A CT arteriogram of the chest, abdomen, and pelvis is the optimal imaging study to

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visualize the aneurysm and is the only one required in most cases. Abdominal ultrasonography is

insufficient as the sole imaging study before aneurysm repair in light of its inability to accurately define

the cephalad extent of the aneurysm and the involvement of the iliac vessels.

Open Repair of Intact Abdominal Aortic Aneurysms

Technique

A significant amount of preparation is required in the operating room before making the incision and

this preparation needs to be coordinated among the surgical and anesthetic teams for both the open and

endovascular approaches. Although the decision about the choice of anesthesia is deferred to the

anesthesiologists, inhalation agents and an endotracheal tube are used most frequently. Adjunctive

epidural anesthesia may improve postoperative pain control177 and may be beneficial in patients with

severe pulmonary disease.178 Adequate intravenous access should be established to facilitate

resuscitation. Central venous access is usually obtained although not necessary. Electrocardiographic

leads, an arterial catheter, and a Foley catheter should be placed for continuous monitoring of the

electrocardiogram, arterial pressure, and urine output, respectively. In addition, a nasogastric tube

should be inserted. A Swan–Ganz pulmonary artery catheter or a transesophageal echocardiogram probe

should be inserted in patients with significant cardiac disease. However, routine use of pulmonary

artery catheters in patients undergoing aortic surgery is not recommended and may be associated with a

higher rate of intraoperative complications.179,180 Peripheral arterial pulses should be interrogated with

either palpation or continuous-wave Doppler ultrasound and marked to facilitate confirmation after

restoration of lower-extremity perfusion. Strategies to maintain core body temperature should be

initiated.179,181 Specifically, the room temperature should be increased, warming devices should be

attached to all intravenous infusion lines, and either a recirculating alcohol blanket or forced-air blanket

should be applied. Bush et al.182 reported that hypothermia (<34.5°C) during AAA repair was associated

with multiple physiologic derangements and adverse outcomes. Of note, this does not pertain to

thoracoabdominal aortic surgery where hypothermia has shown some benefits in spinal cord ischemia

reduction.183

Use of an intraoperative autologous transfusion device should be considered. However, a recent metaanalysis of 5 randomized, controlled trials reported that there is insufficient evidence to recommend its

use during vascular surgery including aortic surgery.184 These devices should likely be used when a

significant amount of blood loss is anticipated, such as during suprarenal or thoracoabdominal aortic

aneurysm repairs. Furthermore, they can be helpful in patients who object to blood transfusions on

religious principles. An extensive operative field from “nipples to toes” should be prepared with the use

of topical antimicrobial agents. A first-generation cephalosporin or vancomycin should be administered

prior to the incision.

AAAs may be repaired through several different incisions or approaches including midline,

retroperitoneal, or transverse (supraumbilical straight, infraumbilical straight, infraumbilical

curvilinear, bilateral subcostal). The incisions or approaches must be viewed as complementary since

neither is perfect for every clinical scenario. Indeed, surgeons should be familiar with the various

approaches and select the optimal one for the clinical setting. The determinants of the incision include

the cephalad/caudal extent of the aneurysm, body habitus, presence of prior abdominal incisions,

presence of abdominal wall stomas, comorbidities, additional intraoperative pathology, inflammatory

aneurysms, renal anomalies, requirements for concomitant procedures, urgency of aortic control, and

surgeon preference. The midline approach is preferable for patients with ruptured AAAs because aortic

control at the level of the diaphragm can be obtained rapidly. The bilateral subcostal approach provides

the best exposure and is the incision of choice for obese patients, those with extensive iliac artery

aneurysms, those patients requiring concomitant renal artery revascularization, and those patients with

juxtarenal aneurysms that require suprarenal aortic control. The retroperitoneal approach is optimal for

patients with multiple previous abdominal incisions (“hostile abdomen”), abdominal wall stomas,

suprarenal aneurysms, inflammatory aneurysms, and horseshoe kidneys. However, the retroperitoneal

approach is limited by the inability to assess the intraperitoneal structures and the limited access to the

right renal artery and right iliac vessels. It was previously contended that the retroperitoneal approach

posed less of a physiologic insult than the transperitoneal approach and, therefore, was ideal for

patients with advanced pulmonary or cardiac disease. However, this has not been supported by a

prospective, randomized trial.185 A detailed description of the retroperitoneal approach is beyond the

context of this chapter, but is available in most standard vascular surgical texts.

The sequence of steps used to repair an intact, infrarenal AAA after a bilateral subcostal incision can

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be summarized (Fig. 96-9). The abdomen is explored after the peritoneal cavity is entered, and both the

gallbladder and colon carefully examined. The lower abdominal wall flap is immobilized to either the

drapes or the pubic towel with the use of penetrating towel clips. The small bowel is manually retracted

laterally to the right, and the duodenum is mobilized by incising the ligament of Treitz. The inferior

mesenteric vein may be suture-ligated at this juncture to facilitate exposure. The tissue adjacent to the

inferior mesenteric vein should be palpated to rule out a large, meandering mesenteric artery. This

artery is an important visceral collateral and should be preserved. The retroperitoneum over the aorta is

incised with the electrocautery, and the left renal vein is exposed. Self-retaining retractors (e.g.,

Bookwalter, Omni retractors) are then placed to facilitate further exposure. The small bowel is placed in

a bowel bag, eviscerated, and retracted laterally to the right with the aid of malleable self-retaining

retractors. The transverse colon and superior abdominal wall flap are retracted cephalad while the

lower abdominal wall is further retracted caudal. The aorta immediately inferior to the renal arteries is

exposed and both renal arteries visualized. The infrarenal aorta at this location is dissected

circumferentially to facilitate placement of a transverse aortic clamp. However, this step may be

omitted if a vertical clamp is used. It is important to identify the course of the renal vein and any

venous anomalies on the preoperative CT scan to prevent inadvertently injuring these structures at this

stage of the procedure. In the presence of a retroaortic renal vein or circumaortic collar, the aortic neck

should not be dissected circumferentially and vascular control should be obtained with a vertical clamp.

The retroperitoneum over the aorta is then incised further caudally and the incision extended along the

course of the right common iliac artery. The extent of the caudal dissection depends on the anatomic

configuration of the aneurysm. If the aneurysm extends to the aortic bifurcation, it is sufficient to

dissect only the common iliac arteries provided a suitable site for clamp application is identified. If the

aneurysm extends to the distal common iliac arteries, both the internal and external iliac vessels should

be dissected free. This may be facilitated on the left side by mobilizing the sigmoid colon along its

peritoneal reflection and reflecting it medially. The inferior mesenteric artery is then dissected free and

vascular control obtained with a vessel loop. Patients are administered 100 units/kg of intravenous

heparin, and the activated clotting time is confirmed to be twice the baseline value. Supplemental doses

of heparin are administered throughout the procedure as dictated by the activated clotting time.

Interestingly, a recent randomized, controlled trial reported that heparin does not reduce thrombotic

events or increase bleeding during aneurysm repair, but is associated with a significant reduction in

myocardial events.186

Figure 96-9. Steps involved in the standard repair of an infrarenal abdominal aortic aneurysm extending into the proximal

common iliac arteries. A: The proximal duodenum is mobilized and the retroperitoneum overlying the aorta incised. The

infrarenal aorta immediately below the renal vein is dissected. The iliac bifurcations are exposed, and vascular clamps are applied

to the infrarenal aorta and distal common iliac arteries after adequate heparinization. A longitudinal arteriotomy is extended from

the infrarenal aorta onto the right common iliac artery. B: Back bleeding from the lumbar arteries is controlled with “figure-ofeight” sutures. The proximal anastomosis is performed in an end-to-end configuration below the renal arteries. The distal

anastomoses are performed at the common iliac bifurcation beyond the aneurysmal segments. The left limb of the graft is tunneled

through the intact left common iliac aneurysm shell. C: The residual aneurysm shell is closed over the prosthetic graft, and the

retroperitoneum is reapproximated to prevent erosion of the graft into the overlying bowel.

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During the time required for adequate mixing of the heparin, the availability of the necessary

equipment is reviewed and confirmed with the operating room personnel. The appropriately sized

prosthetic graft is selected. The graft diameter is sized according to the infrarenal aortic neck by visual

inspection or with the calibrated graft rulers (i.e., “sizers”). The general “rule of thumb” is that the

smaller graft should be selected when the aorta is between two graft sizes because the aorta always

appears smaller after it is transected and redundant graft material at the proximal anastomosis is more

difficult to correct than the opposite problem. A variety of vascular prostheses are available. Despite the

contentions of the various manufacturers, there is no clear advantage for an individual graft and the

choice should be determined by surgeon preference as dictated by ease of handling, cost, and

availability. The distal vascular clamps are applied to the external, internal, or common iliac vessels

depending on the extent of the aneurysm and the character of the vessels. Occasionally, the iliac vessels

are so calcified that they cannot be safely occluded with a clamp. Vascular control may be obtained

intraluminally in this setting with the use of a balloon thromboembolectomy catheter after the

aneurysm has been incised. The proximal aortic clamp is applied in sequence after the distal clamps. The

clamp is applied immediately below the renal arteries to facilitate an anastomosis to the proximal

infrarenal aorta. The length of the infrarenal aorta should be sufficient to permit a safe anastomosis.

However, a long infrarenal cuff should be avoided because it may become aneurysmal over time. Either

a vertical or horizontal aortic clamp may be used. The aorta is then incised longitudinally, and the

incision is extended to the distal aorta and into the iliac arteries if the distal anastomosis will be to the

iliac vessels. Attempts should be made to preserve the autonomic nerves overlying the distal aorta and

proximal left common iliac artery in potent men. This can usually be achieved by incising the left

common iliac artery transversely beyond the aneurysmal portion and tunneling the limb of the graft

through the residual shell. The intraluminal thrombus and debris are removed from within the aorta,

and all back bleeding from the lumbar arteries is controlled with suture ligatures. The atheromatous

debris within the aorta has been reported to be culture-positive in approximately 25% of cases although

this has not been associated with long-term graft infections.187,188 The infrarenal aorta at the level of

the planned proximal anastomosis may be completely transected, or the back wall may be left intact.

Completely transecting the aorta makes the proximal anastomoses slightly easier although leaving the

back wall intact reinforces the anastomosis and provides the equivalent of an autogenous pledget. The

proximal anastomosis is performed in an end–end configuration with a running 3-0 cardiovascular

suture. All leaks in the suture line are repaired with similar 4-0 or 5-0 sutures and felt pledgets as

necessary. The distal anastomosis or anastomoses are performed to the aortic bifurcation, common iliac

arteries, or iliac bifurcation as dictated by the anatomy of the aneurysm. Occasionally, patients with

extensive concomitant iliac disease may require anastomoses at the femoral arteries. A 3-0

cardiovascular suture is used for anastomoses at the aortic bifurcation, and a similar 4-0 suture is used

for the common iliac arteries. All anastomoses are flushed to remove any intraluminal debris before

flow is restored. Blood flow is restored to the pelvis and lower extremities in sequence. Attempts should

be made to flush initially into the internal iliac circulation to prevent embolization to the lower

extremities. This can be facilitated by manually compressing the common femoral arteries for tube graft

configurations. The lower torso should be reperfused gradually (i.e., one vessel at a time and one

extremity at a time) to prevent hypotension. This process requires significant communication and

coordination between the surgical and anesthetic teams. It is imperative that the patient is resuscitated

prior to reperfusion and it is frequently necessary to delay this process to allow the anesthesiologists to

achieve this objective. Reperfusion of the ischemic tissue causes the release of acid, potassium, and a

variety of inflammatory mediators and reactive oxygen species into the systemic circulation, all of

which are potentially detrimental.

The inferior mesenteric artery may be reimplanted into either the body of the graft or the left limb if

it is patent. Seeger et al.189 reported that routine reimplantation of the inferior mesenteric artery

resulted in decreased rates of colonic infarction and death after aortic reconstruction. However, a more

recent randomized, controlled trial demonstrated no benefit in terms of morbidity or mortality although

the authors suggested it may be beneficial for older patients and those with increased blood loss.190 The

colon and lower extremities should be interrogated with the Doppler ultrasound after reperfusion, and

the heparin reversed with intravenous protamine sulfate after confirmation of adequate signals. The

protamine dose is estimated based on the effectiveness of protamine (1 mg of protamine per 100 units

of heparin), the initial dose of heparin, the current activated clotting time, and the elapsed time from

the administration of heparin. The protamine should be administered slowly to prevent any untoward

hemodynamic events.191 Notably, a recent randomized, controlled trial reported that protamine

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effectively reverses the heparin effect, but provides no clinical benefit during peripheral vascular

surgery, including aneurysm repair.192 The shell of the aneurysm and the overlying retroperitoneum are

both closed with absorbable suture to provide a biologic tissue layer between the graft and the viscera.

The retractors are then removed, the viscera are returned to their anatomic positions, the nasogastric

tube is confirmed to be in the antrum, and the abdominal wall fascia is closed with standard technique.

Notably, patients undergoing aortic reconstruction for aneurysmal disease have been reported to have a

higher incidence of abdominal wall hernias than those undergoing reconstruction for occlusive

disease.193–195

The configuration of the aortic reconstruction (aorto-aortic, aortoiliac, aortofemoral) depends on the

extent of aneurysmal involvement and the degree of occlusive disease. Aneurysmal involvement of the

common iliac vessels should be considered an extension of the aortic process and treated appropriately.

Specifically, common iliac arteries larger than 2 cm should be considered aneurysmal and replaced. The

entire common iliac artery must usually be replaced although it is possible to replace only the proximal

segment if the aneurysmal involvement is isolated. Conversely, common iliac arteries smaller than 2 cm

have a relatively benign natural history and do not need to be replaced since only a small percentage

become aneurysmal and require treatment.196,197 Despite the fact that a patient may be a candidate for

an aortic tube graft, it is often easier to perform an aorto-bi-iliac graft because the terminal aorta is

often very calcified. Aorto-bi-femoral bypass grafts should be reserved for the small subset of patients

who truly have concomitant aneurysms and severe occlusive disease since the risks of wound

complications and graft infections are greater. Indeed, the risk for graft infections is less than 0.5% for

aorto-bi-iliac grafts, but approximately 2% for aorto-bi-femoral grafts.196–198 It is important to

remember the original indication for the procedure and choose the appropriate aortic reconstruction

(aorto-bi-iliac bypass for aortoiliac aneurysm, aorto-bi-femoral bypass for aortoiliac occlusive disease).

Admittedly, there is a role for aorto-bi-femoral reconstructions in patients with aneurysm disease, and it

is futile to attempt an aorto-bi-iliac reconstruction in patients with severe external iliac artery disease.

The postoperative care after open repair is fairly routine and predictable for the majority of patients.

Patients are transferred directly from the operating room to the intensive care unit although selective

use of the intensive care unit may be appropriate.199 Most of the patients are extubated in the operating

room or shortly after arrival in the intensive care unit. The intensive care unit length of stay is usually 1

to 2 days, and the median total length of stay is 8 days.34 Patients are encouraged to get out of bed and

begin ambulating in the early postoperative period (i.e., 24 to 48 hours). Preoperative prophylactic

antibiotics are continued for a total of 24 hours. Nasogastric decompression is continued until bowel

function returns. Oral feedings are initiated after removal of the nasogastric tube and advanced quickly

to solids. Patients are discharged when they are ambulatory, can tolerate a regular diet, have normal

bowel function, and are sufficiently able to care for themselves. A subset of people requires transfer to

rehabilitation or extended care facility. Patients are usually seen in the clinic 2 weeks after discharge

and then at 6 months thereafter. Additional clinic appointments may be necessary as dictated by any

ongoing medical problems. Patients are not allowed to drive until their incisional pain has resolved and

they have stopped taking pain medications. Furthermore, patients are discouraged from lifting heavy

objects for the first 6 to 8 weeks to reduce the incidence of incisional hernias.

Complications and Outcome

Open repair of intact AAAs is associated with significant mortality and morbidity.34,200,201 The attendant

mortality rates have been discussed extensively in the preceding sections entitled Principles of

Management and Choice of Open or Endovascular Repair. Briefly, the contemporary mortality rate

across the country has consistently been <5%.72–74 The overall morbidity rate remains less clear,

although the specific complications have been well defined. Huber et al.34 reported that 33% of all

patients undergoing repair of intact AAAs across the United States develop some type of perioperative

complication as defined by the ICD-9 postoperative complication codes. Similarly, Hua et al.73 reported

from the National Surgical Quality Improvement Program – Private Sector that the overall incidence of

30-day morbidity after open repair was 35%.

Intraoperative complications can result from injury to the intra-abdominal structures during dissection

although these technical complications are not specific to the aneurysm repair. The small bowel, colon,

ureter, and major venous structures (inferior vena cava, iliac veins, left renal vein) are particularly

susceptible. Iatrogenic bowel injury at the time of AAA repair is particularly problematic due to the

potential to infect the prosthetic graft. If the colon is injured before the aneurysm repair, the defect in

the colon should be fixed and the aneurysm repair should be aborted. If the small bowel is injured

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