title: Analgesic effect of a single-dose of perineural dexamethasone on ultrasound-guided femoral nerve block after total knee replacement.
abstract: BACKGROUND
  Total knee replacement is usually a very painful procedure. A single-dose of femoral nerve block has been shown to provide similar analgesia to an epidural, with fewer side effects, but limited in time.
  
  
  OBJECTIVE
  To compare the analgesia provided by dexamethasone used at perineural level in the femoral nerve block after total knee replacement with the one used at intravenous level, and with that of a control group.
  
  
  METHODS
  A prospective, randomised, double-blind controlled trial was conducted on 81 patients randomly assigned to one of three groups: 1)IV dexamethasone (8mg); 2)perineural dexamethasone (8mg), and 3)placebo. All patients received 20ml of ropivacaine 0.5% for femoral nerve block. The primary outcome was the duration of the sensory-analgesic block of the femoral nerve block. The secondary outcomes included pain intensity measurements, patient satisfaction, and incidence of complications.
  
  
  RESULTS
  Randomisation was effective. Analgesia duration was significantly higher (P<.0001) in the perineural dexamethasone group (mean 1152.2min, 95% confidence interval [95% CI]: 756.9-1547.6) in comparison with the control group (mean 186min, 95%CI: 81.2-292) and dexamethasone IV group (mean 159.4min, 95%CI: 109.8-209). Postoperative pain, complications and side effects were also lower in this group.
  
  
  CONCLUSIONS
  Dexamethasone prolongs sensory block of single dose of femoral nerve block using ropivacaine. It also provides better analgesia and patient satisfaction, with fewer side effects.
authors.affiliation: Servicio de Anestesiología y Reanimación, Complejo Hospitalario Universitario Juan Ramón Jiménez, Huelva, España. Electronic address: morales.munoz.clara@gmail.com.
authors.forename: C
authors.initials: C
authors.lastname: Morales-Muñoz
authors.affiliation: Servicio de Anestesiología y Reanimación, Complejo Hospitalario Universitario Juan Ramón Jiménez, Huelva, España.
authors.forename: J L
authors.initials: JL
authors.lastname: Sánchez-Ramos
authors.affiliation: Servicio de Anestesiología y Reanimación, Complejo Hospitalario Universitario Juan Ramón Jiménez, Huelva, España.
authors.forename: M D
authors.initials: MD
authors.lastname: Díaz-Lara
authors.affiliation: Servicio de Anestesiología y Reanimación, Complejo Hospitalario Universitario Juan Ramón Jiménez, Huelva, España.
authors.forename: J
authors.initials: J
authors.lastname: González-González
authors.affiliation: Servicio de Anestesiología y Reanimación, Complejo Hospitalario Universitario Juan Ramón Jiménez, Huelva, España.
authors.forename: I
authors.initials: I
authors.lastname: Gallego-Alonso
authors.affiliation: Servicio de Anestesiología y Reanimación, Complejo Hospitalario Universitario Juan Ramón Jiménez, Huelva, España.
authors.forename: M S
authors.initials: MS
authors.lastname: Hernández-Del-Castillo
mesh_terms: D000368:Aged; D000577:Amides; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage* / Q000627:therapeutic use; D000701:Analgesics, Opioid / Q000627:therapeutic use; D000779:Anesthetics, Local; D019645:Arthroplasty, Replacement, Knee; D003907:Dexamethasone / Q000008:administration & dosage* / Q000627:therapeutic use; D004311:Double-Blind Method; D005260:Female; D005267:Femoral Nerve; D006801:Humans; D006943:Hyperglycemia / Q000209:etiology; D015552:Injections, Intralesional; D007275:Injections, Intravenous; D008297:Male; D009020:Morphine / Q000627:therapeutic use; D009407:Nerve Block / Q000379:methods*; D010149:Postoperative Pain / Q000517:prevention & control; D017060:Patient Satisfaction; D020250:Postoperative Nausea and Vomiting / Q000209:etiology; D011446:Prospective Studies; D000077212:Ropivacaine; D018084:Ultrasonography, Interventional
chemical_list: D000577:Amides; D018712:Analgesics, Non-Narcotic; D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D009020:Morphine; D000077212:Ropivacaine; D003907:Dexamethasone
keywords: Analgesia postoperatoria; Bloqueo femoral; Cirugía de prótesis de rodilla; Dexametasona; Dexamethasone; Femoral nerve block; Postoperative analgesia; Total knee replacement