S Group - In the S group, spinal puncture will be performed with the patient in the sitting position, using 27 Gauge (27G) disposable Quincke needles (B. Braun, Meisungen, AG). After obtaining cerebral spinal fluid (CSF), 15 mg of 0.5% hyperbaric bupivacaine will be injected. In case of complete failure, a new puncture will be performed and the same dose of anesthetic drug injected. In cases of partial failure, the anesthesia will be converted to general anesthesia and the patient excluded from the study. All the patients will be sedated with propofol by continuous infusion at an initial dose of 0.5 mg.kg-1 followed by 2 to 5 mg. kg-1.h-1 as necessary to reach level 5 on Ramsay Sedation Scale. The Lichtenstein tension-free method of inguinal hernia repair will be used in both groups and all procedures will be performed by the same surgical team. Patients who exhibit reductions in systolic arterial pressure (SAP) greater than 30% will be given ephedrine (10 mg). Lactated Ringer's solution will be used for fluid replacement therapy at a rate of approximately 500 ml throughout the first 30 minutes, and, then, 2 ml.kg-1.h-1. All of the participants will be given i.v. ketoprofen (100 mg) before the end of the surgery. The time to operating room discharge will be registered.