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

intraoperative placement after the patient has been induced and intubated and central lines have been
placed, with the patient placed in right lateral decubitus position; this is our preferred approach [24,28] . Drain
placement can be deferred until after the operation for unstable patients and patients for whom drain
placement would be difficult. In selected patients, such as those with spinal instrumentation, the CSF drain
can be placed under radiographic guidance. Barring complications, CSF drains are generally removed on
the second or third postoperative day. In patients who lack a reliable neurological exam, such as comatose
patients, the drain may be left in longer.

A CSF drain is placed under sterile conditions. The anatomical landmarks are palpated, and a 14G Tuohy
needle is inserted and advanced into either the L2-L3, L3-L4, or L4-L5 space until clear CSF is acquired. The
lumbar drainage catheter is then advanced into the subarachnoid space, secured with sterile dressings,
connected to the CSF drainage system, and transduced to obtain a baseline CSF pressure. Intraoperative
adjuncts such as naloxone have shown promise in animal models but have not been shown to have reliable
[29]
clinical benefit in human trials . Close monitoring of the MAP from the arterial line and the ISP from the
CSF drain is used to maintain the SCPP at > 70-75 mmHg. The MAP is routinely maintained at
85-100 mmHg, which may require the use of vasopressors along with adequate blood and volume
resuscitation. Our typical strategy is to begin with norepinephrine, then vasopressin; in refractory cases, we
[30]
have successfully used angiotensin II as well . The ISP should be maintained at < 15 mmHg, and CSF can
be drained in 10 mL/h aliquots to achieve this level [24,27,28] .

Anesthesia management and monitoring
Patients undergoing TAAA or DTA repair are transported to the operating room, transferred to the table,
and placed supine onto a bean bag device that will later serve to maintain the surgical position. The
[31]
standard American Society of Anesthesiologists monitors are placed and supplemented with invasive
monitoring. Cerebral oximetry monitors are placed to obtain a baseline reading before preoxygenation.
Premedication is then administered to ease arterial cannulation. A right radial or brachial arterial catheter is
placed before anesthesia is administered; this is preferred over a left upper-extremity arterial line, which can
be compromised during aortic cross-clamping if the left subclavian artery also is clamped. At that critical
juncture, accurate measurement of arterial blood pressure is paramount.

After adequate preoxygenation, general anesthesia is induced using a patient-specific combination of
lidocaine, etomidate, propofol, an opiate such as fentanyl, and a muscle relaxant, with the goal of avoiding
hemodynamic lability during intubation. Use of the short-acting beta-blocker esmolol or the vasodilator
nitroglycerin may be required to avoid significant tachycardia and hypertension, which increase aortic wall
stress and tension and the likelihood of subsequent aortic dissection or aneurysm rupture [24,28] .

The surgical team should notify the anesthesia team if the preoperative computed tomography (CT) scan
suggests bronchial or tracheal compression by the aneurysm, which may necessitate modifying the airway
strategy. Intubation is typically performed using a double-lumen endotracheal tube or, when intraoperative
single-lung ventilation is required, a single-lumen endotracheal tube with a left-sided bronchial blocker.
Correct positioning is confirmed by using fiberoptic bronchoscopy. Anesthesia maintenance involves a
balanced technique with volatile anesthesia, opiate, and dexmedetomidine infusion. Patients whose
diffusing capacity of carbon monoxide is severely reduced may require total intravenous anesthesia;
however, this could cause the loss of beneficial volatile anesthesia-induced cardioprotection.

Generally, central venous access is obtained by cannulating the internal jugular vein with a large-bore
double-lumen catheter, which provides a central port for pulmonary artery catheter placement. We