Plasma Concentrations of Bupivacaine After Peri-articular Injection in Total Knee Arthroplasty

Plasma Concentrations of Bupivacaine After Spinal Anesthesia With Single Shot Femoral Nerve Block and Peri-articular Injection in Total Knee Arthroplasty

Patients with knee arthroplasty usually performed under spinal anesthesia with a single-shot femoral nerve block and periarticular block, so we would like to know the plasma concentration of bupivacaine in these patients.

Inclusion Criteria:

• age of 30-70 yr
• ASA I-II
• patient undergo total knee arthroplasty under spinal block and single shot femoral nerve block and periarticular block

Exclusion Criteria:

• patient's refusal
• allergic to bupivacaine
• body weight less than 50 kg
• liver disease
• heart disease
• coagulopathy
• Hct<35%
• infection at both groin