Closed-loop Sedation of Propofol for Patients Undergoing Spinal Anesthesia

Comparison of Closed-loop Control System of Propofol Versus Manual Control Using Bispectral Index for Controlled Sedation - a Pilot Study

The purpose of this study is to compare the administration of a standard anesthetic drug (propofol) using an automatic, expert-based system versus a manually controlled system by the anesthesiologist. In addition, the performance of the decision support system will be evaluated.

Inclusion Criteria:

• patients undergoing hip or knee replacement under spinal anesthesia

Exclusion Criteria:

• contraindication to spinal anesthesia
• allergies to any study drug