All stakeholders, whether hospital, payer, or patients are now focusing on cost containment, quality improvement, and reducing length of stay for surgical patients. The natural extension of this is a shift in care from the inpatient setting to outpatient and ambulatory surgery centers (ASCs). Due to advances in both surgery and anesthesiology, many operations are now possible in the outpatient setting. For spine surgery alone, annual cost savings of $140 million have been reported with the use of ASCs ¹⁾.