title: A prospective, randomized, double-blinded comparison of ropivacaine 0.5%, 0.75%, and 1% ropivacaine for peribulbar block.
abstract: OBJECTIVE
  To evaluate the efficacy of three different concentrations of ropivacaine (0.5%, 0.75%, and 1%) together with a single concentration of hyaluronidase administered for peribulbar block.
  
  
  METHODS
  Prospective, randomized, double-blind study.
  
  
  METHODS
  Anesthesia department of a university teaching hospital.
  
  
  METHODS
  68 ASA physical status I, II, and III patients undergoing elective cataract surgery.
  
  
  METHODS
  Patients were randomly allocated to receive peribulbar block with 6.5 mL of either 0.5% (Group Ropi-5; n = 22), 0.75% (Group Ropi-7.5; n = 22), or 1% ropivacaine (Group Ropi-10; n = 24). In all patients, 0.5 mL of hyaluronidase was added to the local anesthetic solution.
  
  
  RESULTS
  A larger proportion of patients in Groups Ropi-7.5 (82%) and Ropi-10 (83%) showed complete motor block 15 minutes after injection compared with Group Ropi-5 (55%;p = 0.05, andp = 0.03, respectively). Hypotension (reduction of systolic blood pressure by 30% or more from baseline) was observed in two Group Ropi-5 patients (9%), and two Group Ropi-7.5 patients (9%;p = 0.31), whereas bradycardia (reduction in heart rate < or = 50 bpm) was observed in one Group Ropi-5 patient (4%), and three Group Ropi-10 patients (12%;p = 0.18). Seven hours after surgery, a smaller proportion of Group Ropi-10 patients (64%) showed complete recovery of sensory function as compared with both Group Ropi-5 (94%) and Group Ropi-7.5 (90%;p = 0.03 and p = 0.03, respectively). Complete recovery of motor function 1 hour after surgery was more frequent in Group Ropi-5 (37%) than in Group Ropi-7.5 (5%) or Group Ropi-10 (9%;p = 0.05 and p = 0.05, respectively); however, no other differences in recovery of motor function were observed at any other observation times, with complete recovery in all patients 7 hours after surgery.
  
  
  CONCLUSIONS
  While confirming that ropivacaine is a good option for peribulbar anesthesia, this study demonstrated that the use of 0.75% or 1% concentrations are preferred in that they produce quick and deep sensory and motor block of the operated eye. If recovery of normal motor function is important after surgery, the 0.75% concentration probably represents the best compromise.
authors.affiliation: Department of Anesthesiology, Vita-Salute University of Milano and IRCCS H. San Raffaele, Milan, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Gioia
authors.forename: Guido
authors.initials: G
authors.lastname: Fanelli
authors.forename: Andrea
authors.initials: A
authors.lastname: Casati
authors.forename: Umberto
authors.initials: U
authors.lastname: Nuti
authors.forename: Roberta
authors.initials: R
authors.lastname: Mennella
authors.forename: Monica
authors.initials: M
authors.lastname: Scarioni
authors.forename: Elisa
authors.initials: E
authors.lastname: Cerchierini
authors.forename: Angela
authors.initials: A
authors.lastname: Sciascia
authors.forename: Alessandra
authors.initials: A
authors.lastname: Garassino
authors.forename: Giorgio
authors.initials: G
authors.lastname: Torri
authors.forename: Francesco
authors.initials: F
authors.lastname: Fasce
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Bolognesi
mesh_terms: D000368:Aged; D000577:Amides / Q000009:adverse effects / Q000627:therapeutic use*; D000762:Anesthesia Recovery Period; D000779:Anesthetics, Local / Q000009:adverse effects / Q000627:therapeutic use*; D002387:Cataract Extraction; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006821:Hyaluronoglucosaminidase / Q000627:therapeutic use; D008297:Male; D009407:Nerve Block / Q000379:methods*; D011446:Prospective Studies; D000077212:Ropivacaine; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine; D006821:Hyaluronoglucosaminidase