Intrathecal Morphine and Local Infiltration Analgesia in Total Knee Arthroplasty

Double-blinded randomized control study investigating intrathecal morphine as an additive to spinal anesthesia in patients undergoing elective total knee arthroplasty. The investigators aim to include a total of 120 patients, randomized to two equal groups. Participants in the intervention group are administered intrathecal 0,2mg morphine and 12,5mg bupivacaine for spinal anaesthesia. Participants in the placebo group are administered 12.5mg bupivacaine and saline to match the volume of intervention goup. Primary end points are opioid consumption and possible adverse effects.