Effect of Volatile- Based Versus Total Intravenous Anesthesia on Brain Homeostasis and Neurocognitive Outcome

The brain is a metabolic active organ with constant energy demands. Brain oxygen supply is secured via cerebral circulation. Brain tumor surgery is commonly associated with the tumor's underlying pathophysiology including brain swelling or edema. During craniotomy for brain tumor resection maintenance of cerebral hemodynamic stability is of paramount importance. Neuroinflammation is also a normal response to trauma, such as in the case of brain tumor surgery. The role of neuroinflammation in postoperative brain function is well documented and the aim is to limit it through an appropriate anesthetic approach. Anesthetic agents used during surgery affect brain homeostasis. The anesthetic agent of choice for neurosurgery should deliver smooth and hemodynamically stable anesthesia, good operating conditions, and allow early neurological assessment. Also, the ideal anesthetic agent should preserve cerebral perfusion and neuroprotection. The two most common categories of anesthetic agents used nowadays for elective craniotomy are intravenous and inhalational agents. Propofol is the intravenous anesthetic agent of choice. The action of propofol involves a positive modulation of the inhibitory function of the neurotransmitter gamma-aminobutyric acid (GABA). Propofol causes a decrease in cerebral metabolic rate (CMR), intracranial pressure (ICP), cerebral perfusion pressure (CPP), and cerebral blood flow (CBF). It also is known for its antiemetic properties. Volatile agents commonly used in neuroanesthesia clinical practice are sevoflurane and desflurane. Both of these agents decrease CMR while maintaining stable CPP. CBF alteration is dose-dependent. Desflurane evokes a greater cerebral vasodilation effect than sevoflurane. Sevoflurane is a well-known neuroprotective anesthetic agent traditionally used in neurosurgery. Both desflurane and sevoflurane are associated with early emergence. Thus, this study aimed to explore the effect of volatile-based versus total intravenous anesthesia on cerebral homeostasis and neurocognitive function in patients undergoing elective craniotomy for brain tumor excision aiming to provide a basis for clinical rational drug use in patients undergoing craniotomy resection of supratentorial lesions.