Intrathecal Morphine in Knee Arthroplasty

Determination of the Efficacy and Side-Effect Profile of Lower Doses of Intrathecal Morphine in Patients Undergoing Total Knee Arthroplasty

This study is designed to explore the efficacy lower doses of intra-spinal morphine for pain relief and side effect profiles of same in the setting of Total Knee Replacement.We hypothesized that a dose greater than that used in Total Hip Replacement was needed and wished to find a dose which was effective but had a low side effect profile.

Inclusion Criteria:

• Patients for elective total knee arthroplasty

Exclusion Criteria:

• No contraindication to spinal
• No allergy to morphine, rescue analgesia or anti-emesis treatment.