The investigators conduct a random assignment into either the remimazolam group or the propofol group. Depending on the group assignment, either remimazolam (0.2 mg/kg) or propofol (1.0 mg/kg) is administered. If necessary, additional doses of remimazolam (0.1 mg/kg) or propofol (0.5 mg/kg) are given. The standard anesthesia procedure of our institution is followed, and blood pressure data recorded during the surgery is analyzed (mean arterial pressure <65mmHg is defined as hypotension).

Inclusion Criteria:

Patients who undergo robot-assisted laparoscopic prostatectomy and who have taken renin-angiotensin system blockers for more than 3 months.

Exclusion Criteria:

1. emergency surgery
2. If the subject includes those who cannot read the consent form (e.g. illiterate, foreigners, etc.)
3. cognitive dysfunction
4. Atrial fibrillation, moderate to severe valvular disease, ejection fraction of 35% or less
5. Patients who did not take renin-angiotensin system blockers on the day of surgery