Optional brain relaxation improves the surgeon's operating conditions and is likely to
minimize the degree of retraction injury ,with the potential for providing patients with a
better outcome. The choice of anesthetic drugs can affect intraoperative brain relaxation.
Propofol suppresses brain metabolism, reduces cerebral blood flow, and provides satisfactory
brain relaxation. Desflurane is often criticized in neurosurgery due to its cerebral
vasodilation and potential to increase intracranial pressure, however, it has been found to
have a little clinical significance. This study intends to compare the effects of desflurane
with propofol on brain relaxation in patients with supratentorial tumors under mild
hyperventilation, and to provide new clinical evidence for the use of desflurane in
neurosurgical anesthesia.