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Page 8 of 16 Katz et al. Vessel Plus 2023;7:1 https://dx.doi.org/10.20517/2574-1209.2022.52

recommend routine use of pulmonary artery catheters, along with monitoring of the cardiac index and
mixed venous oxygen saturation. Pulmonary artery catheter placement not only assists in the intraoperative
assessment of cardiac function, volume status, and pulmonary pressures (especially during single-lung
ventilation), but also can be invaluable in managing a hemodynamically unstable patient postoperatively.
Our center recommends concomitant use of a large-bore triple-lumen cannula and a second large-bore
single-lumen sheath through which the pulmonary artery catheter can be placed, given that rapid
transfusion may be necessary . To facilitate rapid infusion at rates > 500 mL/min, we use the Belmont
[24]
Rapid Infuser FMS2000 (Belmont Medical Technologies, Billerica, MA) and cell-salvage blood
conservation . Central lines that are not being utilized are removed promptly in the postoperative period
[32]
to reduce the risk for infection.

Intraoperative transesophageal echocardiography should be considered for assessing cardiac function and
volume status during periods of hemodynamic instability. It can also be used to assist in placing left heart
bypass cannulas. Transesophageal echocardiography should be used in patients with preexisting coronary
disease or heart failure (left ventricular ejection fraction < 40%), as echocardiography is more sensitive than
[27]
electrocardiography in detecting myocardial ischemia .

POSTOPERATIVE MANAGEMENT AND CONSIDERATIONS
The postoperative course of patients who have undergone open TAAA or DTA repair is often characterized
by coagulopathy, reperfusion injury, and risk for bleeding and/or ischemia . In a study of 3309 patients, we
[2]
found that operative mortality for TAAA repair ranged from 5% to 10%, depending on preexisting
comorbidities and the anatomical extent of the aneurysm . Other large series consisting of more than 500
[7]
combined TAAA and DTA repairs reported operative mortality rates of 6% to 16% [33-35] . As expected, the
highest risk is with extent II aneurysm repair. A detailed procedure for patient handoff from the surgical
and anesthesia teams to the intensive care unit (ICU) team is essential for proper communication and
optimal continuity of care . The fundamental areas of focus in the immediate postoperative period are
[36]
maintaining adequate MAP, volume resuscitation, rewarming, and expectant management of potential
[2]
complications. An example of a system-by-system approach to postoperative care is shown in Figure 3 .

Neurological (cerebral)
As with any operation involving manipulation of the aorta, there is the possibility of stroke. The overall risk
for stroke in the acute perioperative period for patients undergoing TAAA repair is about 2% to 3% ; the
[7]
risk is highest with extent II aneurysms and lowest with extent III aneurysms. Most strokes are ischemic or
embolic, with only a small minority being hemorrhagic. Embolic stroke is caused either by dislodgement of
atheromatous debris or entrainment of air during surgery. Fluctuations in blood pressure can induce
hypotensive stroke, particularly during reperfusion or if significant bleeding develops. Approximately one-
quarter of patients noted to have stroke symptoms will recover without deficits .
[7]

After the patient awakens from anesthesia, any focal neurologic deficits should be quickly evaluated with
noncontrast head CT to exclude a hemorrhagic cause. Prompt neurosurgical consultation should be
obtained if hemorrhage has been noted.

Neurological (spinal cord)
Spinal cord deficits are the most feared major morbidity after TAAA or DTA repair, particularly after
operations for extent II or III aneurysms. The risk for spinal cord deficit has decreased significantly in
recent years: In 1991, Crawford’s group reported that the incidence of spinal cord deficit in 1509 TAAAs
was 16% overall and as high as 31% in patients needing extent II repairs ; by 2016, the overall rate had
[37]