[Femoral nerve block for postoperative analgesia after anterior cruciate ligament reconstruction: comparison of 2 concentrations of bupivacaine with clonidine in 3 modes of administration].
BACKGROUND
The continuous femoral nerve block is used for postoperative orthopedic analgesia.


OBJECTIVE
To evaluate 2 concentrations of bupivacaine with clonidine in 3 methods of administration for performing a continuous femoral nerve block.


METHODS
Randomized controlled trial in ASA 1-2 patients in 6 groups. In groups 1, 2, and 3, the combination used was 0.125% bupivacaine plus clonidine. In groups la, 2a, and 3a, the combination was 0.0625% bupivacaine plus clonidine. Methods of administration were as follows: groups 1 and la, 10 mL x h(-1) in continuous infusion; groups 2 and 2a, 5 mL h x (-1) in continuous infusion plus 2.5 mL every 30 minutes through a patient-controlled analgesia (PCA) system; groups 3 and 3a, 5 mL every 30 minutes in a PCA system. Pain on a visual analog scale (VAS) and amounts of bupivacaine and morphine used were recorded 2 and 48 hours after surgery.


RESULTS
A total of 105 patients were enrolled: 17 in group 1, 18 in group la, 18 in group 2, 17 in group 2a, 17 in group 3, and 18 in group 3a. No significant differences between any of the 6 groups were observed for patient characteristics, postoperative VAS scores, or morphine use.


CONCLUSIONS
A continuous femoral nerve block is useful for managing pain after anterior cruciate ligament surgery. The application of 5 mL x h(-1) in continuous infusion or in PCA system bolus doses provides excellent postoperative analgesia. Use of 0.0625% bupivacaine decreases overall consumption of analgesic and is not detrimental to quality of analgesia.
Contreras-Dominguez
V
V
Servicio de Anestesiología, Hospital Clinico Regional de Concepción, Chile. vcontreras@netanestesia.cl
Carbonell-Bellolioa
P
P
Ojeda-Greciet
A
A
Sanzana
E S
ES
D000293:Adolescent; D000328:Adult; D016058:Analgesia, Patient-Controlled / Q000009:adverse effects / Q000706:statistics & numerical data; D000700:Analgesics / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D000779:Anesthetics, Local / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D002045:Bupivacaine / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D003000:Clonidine / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D005267:Femoral Nerve / Q000187:drug effects*; D006801:Humans; D007262:Infusions, Intravenous; D007660:Ketoprofen / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D009407:Nerve Block / Q000379:methods*; D019637:Orthopedic Procedures; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D017060:Patient Satisfaction; D020250:Postoperative Nausea and Vomiting / Q000139:chemically induced; D019651:Plastic Surgery Procedures
D000700:Analgesics; D018712:Analgesics, Non-Narcotic; D000779:Anesthetics, Local; D009020:Morphine; D007660:Ketoprofen; D003000:Clonidine; D002045:Bupivacaine