*2.2.3 Choice of anesthesia techniques*

General anesthesia is recommended for revascularization surgery. The goal of anesthesia induction is to maintain hemodynamics, oxygenation, and ventilation. It also aims to avoid a decrease in cerebral perfusion pressure (CPP) and increased intracranial pressure (ICP), which are attributed to anesthetic drugs and airway maneuvers. The choice of induction technique for general anesthesia (intravenous versus inhalational agents) has been debated and depends on patient factors (pediatric versus adult), surgical factors (use of neurophysiologic monitoring), and potential for compromised or difficult airway [18, 39, 40]. Sakamoto et al. investigated the perioperative course of 216 patients undergoing revascularization; they concluded that the incidence of postoperative ischemic events was associated with the severity of the disease and surgical procedure than with other factors, including anesthetic management (inhaled, IV, and balanced anesthesia) [40].

Sato et al. studied the effect of total intravenous anesthesia (TIVA) versus volatile anesthetic on cerebral circulation in MMD and concluded that volatile agents might reduce the regional cortical blood flow and hence, inducing intracerebral steal; this was not observed with TIVA [41]. More recently, studies demonstrated improved outcomes when TIVA is used [42], whereas other studies have not shown a significant difference between TIVA versus inhalational agents in MMD [43]. Many centers are routinely utilizing total intravenous anesthesia (TIVA) with target-controlled infusion (TCI) of propofol and opioids (remifentanil) for the neurosurgical procedure [44]. In TCI, the infusion pumps are set to deliver a bolus on induction followed by a maintenance infusion based on the patient's demographics. TIVA with propofol and remifentanil offers theoretical advantages for neurosurgical procedures such as careful and easy titration of anesthetic to maintain the hemodynamics intraoperatively; and most notably rapid, smooth emergence with early recovery of neur0cognitive function without postoperative nausea and vomiting. Additionally, TIVA is an anesthetic of choice in neurosurgery during neurophysiological monitoring (SSEP). In conclusion, more prospective studies are needed to determine the influence of different anesthetic techniques on revascularization surgery and its outcome.
