title: Randomized, comparative study of the effectiveness of three different techniques of interscalene brachial plexus block using 0.5% ropivacaine for shoulder arthroscopy.
abstract: BACKGROUND
  Interscalene brachial plexus block is an effective regional anesthesia technique for shoulder surgeries. The superiority of the popular ultrasound-guided blocks over peripheral nerve stimulator-confirmed blocks remains unclear. In this study the efficacy of these different block techniques was compared.
  
  
  METHODS
  This prospective, randomized, clinical study included 109 patients (ASA grades I-III) who receive 20 mL 0.5% ropivacaine with ultrasound-guided blocks (U group), peripheral nerve stimulator-confirmed blocks (N group), or ultrasound-guided and peripheral nerve stimulator-confirmed blocks (dual guidance; NU group) for elective shoulder arthroscopy. Block onset time, duration, and effectiveness on the Lovett rating scale were assessed.
  
  
  RESULTS
  There was no statistically significant intergroup difference in duration of block performance, irrespective of the technique (P = 0.232). Onset time of complete warmth sensation loss (P < 0.001) and muscle strength abolition (P < 0.001) was significantly longer and mean Lovett rating scale score distribution was significantly higher in the N group than in the other groups (P < 0.001). These findings show a statistically significant correlation between the performance of the used block technique and the necessity of conversion to general anesthesia because of insufficient block in the N group (58.54%) than in the U (24.44%) and NU (19.57%) groups.
  
  
  CONCLUSIONS
  Peripheral nerve stimulator-confirmed needle placement is not necessary to ensure effectiveness of ultrasound-guided blocks, which is expressed as a lack of necessity of conversion to general anesthesia. Nevertheless, the dual guidance technique is recommended to reduce the risk of complications and might be considered the regional anesthesia of choice for shoulder surgery.
authors.forename: Michał
authors.initials: M
authors.lastname: Kolny
authors.affiliation: Department of Anaesthesiology and Intensive Therapy, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia, Katowice, Poland, St. Barbara's. mstasiowski.anest@gmail.com.
authors.forename: Michał J
authors.initials: MJ
authors.lastname: Stasiowski
authors.forename: Marek
authors.initials: M
authors.lastname: Zuber
authors.forename: Radosław
authors.initials: R
authors.lastname: Marciniak
authors.forename: Ewa
authors.initials: E
authors.lastname: Chabierska
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Pluta
authors.forename: Przemysław
authors.initials: P
authors.lastname: Jałowiecki
authors.forename: Tomasz
authors.initials: T
authors.lastname: Byrczek
mesh_terms: D000293:Adolescent; D000328:Adult; D000577:Amides / Q000008:administration & dosage*; D000768:Anesthesia, General / Q000379:methods; D000779:Anesthetics, Local / Q000008:administration & dosage; D001182:Arthroscopy / Q000379:methods*; D065527:Brachial Plexus Block / Q000379:methods*; D017558:Elective Surgical Procedures / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009339:Needles; D011446:Prospective Studies; D000077212:Ropivacaine; D012785:Shoulder Joint / Q000601:surgery*; D013997:Time Factors; D018084:Ultrasonography, Interventional / Q000379:methods; D055815:Young Adult
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine
keywords: Lovett’s Rating Scale; brachial plexus; interscalene brachial plexus block; local anaesthetic; peripheral nerve stimulator; ultrasound