Optimal dose of intrathecal isobaric bupivacaine in total knee arthroplasty

Purpose Early mobilization is an important aspect of fast-track protocols and intrathecal bupivacaine is often used in primary total knee arthroplasty (TKA). Although the optimal dose is not known, conventional doses leave patients unable to mobilize for two to four hours. The dose of an intrathecally administered local anesthetic should therefore be optimized to achieve immediate postoperative mobilization. This study determined the median effective dose (ED) of intrathecal bupivacaine for primary unilateral TKA.