title: Re-evaluation of hyaluronidase in peribulbar anaesthesia.
abstract: OBJECTIVE
  Hyaluronidase can augment the actions of local anaesthetics in peribulbar anaesthesia. However, evidence suggests satisfactory anaesthesia can be achieved using mixtures without hyaluronidase. A randomised double blind study was conducted on 50 patients, undergoing peribulbar anaesthesia, to validate this observation.
  
  
  METHODS
  Patients received a standard mixture of local anaesthetic (0.5% bupivacaine and 2% lignocaine in a 1:1 ratio) with or without hyaluronidase (25 IU/ml of mixture), pH values 5.16 and 5.24 respectively. Time taken to establish satisfactory anaesthesia to allow surgery was noted.
  
  
  RESULTS
  The onset time to globe akinesia in the control group ranged from 2 to 15 minutes (mean 5.64 and median 4 minutes) and in the hyaluronidase group from 2 to 12 minutes (mean 4.64 and median 4 minutes). The volume of local anaesthetic injected to achieve satisfactory anaesthesia ranged from 8 to 16 ml (mean 10.96, SD 1.95) in the control group and 10 to 18 ml (mean 11.64, SD 2.8) in the hyaluronidase group. A Mann-Whitney test to compare onset times to globe akinesia between groups gave a p value = 0.6 and 95% confidence interval (-1 to 2 minutes).
  
  
  CONCLUSIONS
  Addition of 25 IU/ml of hyaluronidase to a standard pH unadjusted local anaesthetic mixture does not significantly reduce the time to the onset of satisfactory globe akinesia.
authors.affiliation: Glan Hafren NHS Trust Hospitals, Newport, Gwent.
authors.forename: D P
authors.initials: DP
authors.lastname: Prosser
authors.forename: G E
authors.initials: GE
authors.lastname: Rodney
authors.forename: T
authors.initials: T
authors.lastname: Mian
authors.forename: H M
authors.initials: HM
authors.lastname: Jones
authors.forename: M Y
authors.initials: MY
authors.lastname: Khan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000772:Anesthesia, Local / Q000379:methods* / Q000592:standards; D000779:Anesthetics, Local; D002045:Bupivacaine / Q000008:administration & dosage; D002387:Cataract Extraction; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006821:Hyaluronoglucosaminidase; D008012:Lidocaine / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged
chemical_list: D000779:Anesthetics, Local; D008012:Lidocaine; D006821:Hyaluronoglucosaminidase; D002045:Bupivacaine