title: Ultrasound-aided ipsilateral-dominant epidural block for total hip arthroplasty: a randomised controlled single-blind study.
abstract: OBJECTIVE
  Lumbar epidural anaesthesia usually affects both legs. The aim was to compare the success rates of ultrasound-aided vs. classical midline epidural catheter insertion for ipsilateral-dominant blocks and analgesia in patients undergoing total hip arthroplasty.
  
  
  METHODS
  The protocol was designed as a prospective randomised single-blind study. In the ultrasound group (n = 12), ultrasound examination was performed to determine the puncture point and direction for ipsilateral-dominant block. In the midline group (n = 12), epidural puncture was performed by the usual midline approach. Rates of successful ipsilateral-dominant block using 6 ml of lidocaine 1.5% wt vol⁻¹ (primary outcome) and effects of patient-controlled epidural analgesia using ropivacaine 0.2% wt vol⁻¹ (secondary outcomes) were evaluated.
  
  
  RESULTS
  The rates of successful ipsilateral-dominant block were 83% in the ultrasound group and 17% in the midline group (P = 0.004). Sensory and motor functions on the non-operated side in the ultrasound group were significantly better maintained than those on the operated side and compared with those on the non-operated side in the midline group (P < 0.05). Pain scores at mobilisation, incidence of post-operative nausea and vomiting and frequency of use of supplemental analgesics were significantly lower in the ultrasound group than in the midline group (P < 0.05).
  
  
  CONCLUSIONS
  The use of ultrasound significantly improves the success rate of ipsilateral epidural block compared with the standard midline approach.
authors.affiliation: Department of Anaesthesiology, Sapporo Medical University School of Medicine, Hokkaido, Japan.
authors.forename: Ryo-ichi
authors.initials: R
authors.lastname: Kawaguchi
authors.forename: Masanori
authors.initials: M
authors.lastname: Yamauchi
authors.forename: Shigekazu
authors.initials: S
authors.lastname: Sugino
authors.forename: Michiaki
authors.initials: M
authors.lastname: Yamakage
mesh_terms: D000368:Aged; D000577:Amides / Q000008:administration & dosage; D016058:Analgesia, Patient-Controlled / Q000379:methods; D000767:Anesthesia, Epidural / Q000379:methods; D000779:Anesthetics, Local / Q000008:administration & dosage*; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods*; D010147:Pain Measurement; D011446:Prospective Studies; D000077212:Ropivacaine; D016037:Single-Blind Method; D018084:Ultrasonography, Interventional / Q000379:methods*
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine; D008012:Lidocaine