title: [Differences of analgesic efficacy and complication rates between ultrasound and nervestimulator guided peripheral nerve catheters : Database analysis on patient-relevant target parameters].
abstract: BACKGROUND
  Peripheral nerve catheters (PNC) play an important role in postoperative pain treatment following major extremity surgery. There are several trials reported in the literature which investigated the efficacy and safety of ultrasound (US) and nerve stimulator (NS) guided PNC placement; however, most of these trials were only small and focused mainly on anesthesiologist-related indicators of block success (e.g. block onset time and procedure time) but not primarily on patient-related outcome data including postoperative pain during movement.
  
  
  OBJECTIVE
  This retrospective analysis compared the analgesic efficacy and safety of US versus NS guided peripheral nerve catheters (PNC) for postoperative pain therapy in a large cohort of patients.
  
  
  METHODS
  Data of patients (June 2006-December 2010) treated with US (nus = 368 June 2008-December 2010) and NS (nns = 574, June 2006-May 2008) guided PNC were systematically analyzed. Apart from demographic data, postoperative pain scores [numeric rating scale (NRS): 0-10] on each treatment day, the number of patients with need for additional opioids, cumulative local anesthetic consumption and catheter-related complications were compared.
  
  
  RESULTS
  On the day of surgery patients treated with US-guided PNC reported lower NRS at rest (p = 0.034) and during movement (p < 0.001). Additionally, the number of patients requiring additional opioids on the day of surgery was lower in the US group (absolute difference 12.4 %, p = 0.001). Furthermore, the number of multiple puncture attempts (absolute difference 5.6 %, p < 0.001) and failed catheter placements (absolute difference 3.4 %, p = 0.06) were lower in the US group. There were no patients in both groups with long-lasting neurological impairment.
  
  
  CONCLUSIONS
  This database analysis demonstrated that patients treated with US-guided PNC reported significantly lower postoperative pain scores and the number of patients requiring additional opioids was significantly lower on the day of surgery. The numbers of multiple punctures and failed catheter placements were reduced in the US group, which might be seen as an advantage of US-guided regional anaesthesia.
authors.affiliation: Klinik für Anästhesiologie, Intensivmedizin und Schmerztherapie, Universitätsklinikum Münster, Albert-Schweitzer-Campus 1 (Gebäude A1), 48149, Münster, Deutschland.
authors.forename: A
authors.initials: A
authors.lastname: Schnabel
authors.forename: B
authors.initials: B
authors.lastname: Middendorf
authors.forename: M G
authors.initials: MG
authors.lastname: Boschin
authors.forename: A
authors.initials: A
authors.lastname: Gottschalk
authors.forename: H
authors.initials: H
authors.lastname: Van Aken
authors.forename: P K
authors.initials: PK
authors.lastname: Zahn
authors.forename: E M
authors.initials: EM
authors.lastname: Pogatzki-Zahn
mesh_terms: D000328:Adult; D000368:Aged; D000698:Analgesia; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000627:therapeutic use; D000765:Anesthesia, Conduction / Q000009:adverse effects / Q000379:methods*; D002406:Catheterization, Peripheral / Q000009:adverse effects / Q000379:methods*; D016208:Databases, Factual; D004558:Electric Stimulation / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000009:adverse effects / Q000379:methods*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy; D010525:Peripheral Nerves / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D018084:Ultrasonography, Interventional / Q000009:adverse effects / Q000379:methods*
chemical_list: D000701:Analgesics, Opioid