title: Comparing the analgesia effects of single-injection and continuous femoral nerve blocks with patient controlled analgesia after total knee arthroplasty.
abstract: We compared the analgesic effects of single-injection or continuous femoral nerve block (FNB) with intravenous patient controlled analgesia (PCA) opioids. Two hundred patients undergoing knee arthroplasty were randomized to one of the three regimens. Significant knee pain on movement at postoperative 24h was reduced with single-injection (OR 0.30; 95% CI 0.12 to 0.74; P=0.009) or continuous (OR 0.21; 95% CI 0.08 to 0.51; P=0.001) FNB, compared with PCA. Allocation to FNBs also resulted in significantly less opioid consumption, fewer episodes of nausea and vomiting, and achieved knee flexion 90° earlier than allocation to PCA. Compared to single-injection FNB, patients with continuous FNB had lower pain scores on movement at 24h (mean difference -0.57; 95% CI -1.14 to -0.01; P=0.045), consumed less opioid, and had fewer incidences of nausea and vomiting. The analgesic efficacy of single-injection and continuous FNBs was superior to PCA in the immediate postoperative period; with continuous FNB providing better analgesia than single-injection FNB.
authors.affiliation: Faculty of Health Science, University of Sydney, New South Wales, Australia.
authors.forename: Ee-Yuee
authors.initials: EY
authors.lastname: Chan
authors.forename: Marlene
authors.initials: M
authors.lastname: Fransen
authors.forename: Sathappan
authors.initials: S
authors.lastname: Sathappan
authors.forename: Nicholas H L
authors.initials: NH
authors.lastname: Chua
authors.forename: Yiong-Huak
authors.initials: YH
authors.lastname: Chan
authors.forename: Nelson
authors.initials: N
authors.lastname: Chua
mesh_terms: D000368:Aged; D000698:Analgesia; D016058:Analgesia, Patient-Controlled; D000701:Analgesics, Opioid / Q000008:administration & dosage*; D019645:Arthroplasty, Replacement, Knee; D005260:Female; D005267:Femoral Nerve; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods*; D010149:Postoperative Pain / Q000517:prevention & control*
chemical_list: D000701:Analgesics, Opioid