Does IVPCA Increase Opioid Consumption and Side Effects in Fast Track Orthopedic Procedures?

The study aims to compare the use of intravenous patient controlled analgesia (IVPCA) versus the delivery of pain relief (per oral and intravenous (IV) medications as rescues analgesia) on an as needed basis within a well defined fast track protocol that includes multimodal analgesia for patients who are undergoing elective primary knee replacement surgery. The investigators assumed that with the multimodal analgesia regimen without the use of IVPCA will demonstrate decreased consumption of postoperative opioids, reduced incidence of opioids related side effects and decreased length of stay in the hospital.