title: Interscalene brachial plexus anesthesia and analgesia for open shoulder surgery: a randomized, double-blinded comparison between levobupivacaine and ropivacaine.
abstract: We compared the onset time and quality of interscalene brachial plexus block produced with levobupivacaine and ropivacaine in 50 patients undergoing open shoulder surgery randomly allocated to receive 30 mL of 0.5% levobupivacaine (n = 25) or 0.5% ropivacaine (n = 25) injected through a 20-gauge catheter placed into the interscalene sheath using a 18-gauge insulated and stimulating Tuohy introducer. The block was also prolonged after surgery using a patient-controlled interscalene analgesia with 0.125% levobupivacaine or 0.2% ropivacaine, respectively (basal infusion rate, 6 mL/h; bolus, 2 mL; lockout period, 15 min; maximum boluses per hour, three). Three patients (two with levobupivacaine [8%] and one with ropivacaine [4%]) failed to achieve surgical block within 45 min after the injection and were excluded. The onset time of surgical block was 20 min (10-40 min) with levobupivacaine and 20 min (5-45 min) with ropivacaine (P = 0.53). Rescue intraoperative analgesia (0.1 mg of fentanyl IV) was required in eight patients in each group (34%) (P = 0.99). Forty-two patients completed the 24-h postoperative infusion (22 with levobupivacaine and 20 with ropivacaine). Postoperative analgesia was similarly effective in both groups. Total consumption of local anesthetic infused during the first 24 h was 147 mL (144-196 mL) with levobupivacaine and 162 mL (144-248 mL) with ropivacaine (P = 0.019), with a ratio between boluses received and requested of 0.8 (0.4-1.0) and 0.7 (0.4-1.0), respectively (P = 0.004). The degree of motor block of the operated limb was deeper with levobupivacaine than ropivacaine when starting postoperative analgesia; however, no further differences in degree of motor function were observed between the two groups. We conclude that 30 mL of levobupivacaine 0.5% induces an interscalene brachial plexus anesthesia of similar onset and intensity as the one produced by the same volume and concentration of ropivacaine. Postoperative interscalene analgesia with 0.125% levobupivacaine results in similar pain relief and recovery of motor function with less volume of local anesthetic than with 0.2% ropivacaine.
  
  
  CONCLUSIONS
  This prospective, randomized, double-blinded study demonstrates that 30 mL of 0.5% levobupivacaine produces an interscalene brachial plexus block of similar onset and quality as the one produced by the same volume of 0.5% ropivacaine. When prolonging the block after surgery, 0.125% levobupivacaine provides adequate pain relief and recovery of motor function after open shoulder surgery, with less volume infused during the first 24 h after surgery than 0.2% ropivacaine.
authors.affiliation: Department of Anesthesiology and Orthopedic Surgery, Vita-Salute University of Milano, IRCCS H. San Raffaele, Italy. casati.andrea@hsr.it
authors.forename: Andrea
authors.initials: A
authors.lastname: Casati
authors.forename: Battista
authors.initials: B
authors.lastname: Borghi
authors.forename: Guido
authors.initials: G
authors.lastname: Fanelli
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Montone
authors.forename: Roberto
authors.initials: R
authors.lastname: Rotini
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Fraschini
authors.forename: Federico
authors.initials: F
authors.lastname: Vinciguerra
authors.forename: Giorgio
authors.initials: G
authors.lastname: Torri
authors.forename: Jacques
authors.initials: J
authors.lastname: Chelly
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000577:Amides; D000779:Anesthetics, Local; D001917:Brachial Plexus; D002045:Bupivacaine; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009407:Nerve Block; D019637:Orthopedic Procedures; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D017060:Patient Satisfaction; D000077212:Ropivacaine; D018401:Sample Size; D012782:Shoulder / Q000601:surgery*
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine; D002045:Bupivacaine