title: A prospective randomized double-blinded controlled study of ropivacaine 0.75% versus bupivacaine 0.5%-mepivacaine 2% for peribulbar anesthesia.
abstract: OBJECTIVE
  Ropivacaine 1% has recently been used in clinical trials for peribulbar anesthesia. This study aims to compare the safety and the efficacy of ropivacaine 0.75% with that of a 1:1 mixture of bupivacaine 0.5% and mepivacaine 2% for peribulbar anesthesia.
  
  
  METHODS
  Two thousand patients undergoing peribulbar anesthesia for elective cataract phacoemulsification were prospectively studied over a 1-year period and randomly assigned to 1 of 2 groups according to the local anesthetic used. One thousand patients were administered peribulbar anesthesia with 9 mL of ropivacaine 0.75% plus 1 mL of hyaluronidase (group R), and 1,000 patients received peribulbar anesthesia with 4 mL of bupivacaine 0.5% plus 4 mL of mepivacaine 2% plus 1 mL of hyaluronidase plus 1 mL of sodium bicarbonate (group BM). Peribulbar anesthesia was always accomplished by the same physician by 2 injections of 5 mL each, with a 25-gauge 25-mm needle. Evaluation was performed by another physician blinded to the technique used and included assessment of pain on local anesthetic injection, ocular and eyelid akinesia, need for top-up injections, onset time and duration of anesthesia, intraoperative analgesia, duration of surgery, hemodynamic parameters, and incidence of perioperative complications.
  
  
  RESULTS
  A greater incidence of pain on injection was found in group BM (P<.001). No difference between the groups was found regarding the onset time and the duration of anesthesia. Perioperative analgesia was satisfactory in both groups with no significant difference. Patients in group R showed a reduced need for top-up injection and a better ocular akinesia at 8 and 10 minutes (P<.01). The akinesia of the eyelid was comparable in the 2 groups and complete in all cases at 8 minutes. Cardiac arrhythmias were more frequent in group BM (P<.01). Local complications did not differ between the groups. An increase in mean artierial blood pressure and heart rate was observed in both groups 1 minute after injection of local anesthetic.
  
  
  CONCLUSIONS
  Peribulbar anesthesia with ropivacaine provided better ocular akinesia 8 to 10 minutes after block insertion than a bupivacaine-mepivacaine mixture, which reduced the need for top-up injections. Ropivacaine also caused less pain on injection.
authors.affiliation: Department of Anesthesia and Intensive Care, Fatebenefratelli and Ophthalmiatric Hospital, Milano, Italy. lap.luc@tiscalinet.it
authors.forename: M
authors.initials: M
authors.lastname: Luchetti
authors.forename: G
authors.initials: G
authors.lastname: Magni
authors.forename: G
authors.initials: G
authors.lastname: Marraro
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000577:Amides / Q000008:administration & dosage*; D000698:Analgesia; D000704:Analysis of Variance; D000772:Anesthesia, Local / Q000295:instrumentation / Q000379:methods; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001145:Arrhythmias, Cardiac / Q000139:chemically induced; D001794:Blood Pressure / Q000187:drug effects; D002045:Bupivacaine / Q000008:administration & dosage*; D002387:Cataract Extraction; D016009:Chi-Square Distribution; D004311:Double-Blind Method; D017558:Elective Surgical Procedures; D005123:Eye / Q000187:drug effects; D005143:Eyelids / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008619:Mepivacaine / Q000008:administration & dosage*; D009339:Needles / Q000009:adverse effects; D010147:Pain Measurement; D017060:Patient Satisfaction; D011446:Prospective Studies; D000077212:Ropivacaine; D012449:Safety; D013997:Time Factors
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine; D008619:Mepivacaine; D002045:Bupivacaine