Analgesic Effect of Perineural Fentanyl Additive to Local Anesthetics in Femoral Nerve Block

Femoral Nerve Block in Patient With Total Knee Arthroplasty; Analgesic Effect of Perineural Fentanyl Additive to Local Anesthetics

The purpose of this study is to evaluate the analgesic efficacy of perineural fentanyl combined with local anesthetics in the post operative pain control with continuous femoral nerve block after total knee arthroplasty.

Inclusion Criteria:

• patients who scheduled to receive knee arthroplasty with general anesthesia
• ASA physical status 1 or 2

Exclusion Criteria:

• allergy to drug
• refuse to the study
• ASA physical status 3 and 4
• history of drug abuse
• cognitive disfunction such as dementia
• patients who do not adequate for general anesthesia