The study will enroll a total of 140 adult patients undergoing hip or knee arthroplasty (equal numbers) at Barnes-Jewish-Hospital. These procedures will be randomized with 50% of the procedures performed under spinal anesthesia and 50% procedures performed under general anesthesia.
Patients randomized to spinal anesthesia will receive sedation with dexmedetomidine up to 1 mcg/kg/min, and then add small dose of propofol (up to 50 mcg/kg/min) and fentanyl at the discretion of the anesthesia provider the Richmond Agitation and Sedation Scale (RASS) -2 to -3. Headphones to play music will be offered to patients undergoing spinal anesthesia to minimize the noise generated from the surgical intervention.
The investigators will study the effect of spinal anesthesia versus general anesthesia on cardiac biomarker levels in hip and knee arthroplasty population (levels of Hs-cTnI postoperatively compared to baseline values) Also, the incidence of postoperative renal injury using investigational renal biomarkers, Myo-Inositol Oxygenase (MIOX) and Nephrocheck