Peribulbar anaesthesia: the role of local anaesthetic volumes and Thiomucase in motor block and intraocular pressure.
Peribulbar anaesthesia is a useful regional anaesthesia and akinesia technique for eye surgery. We studied changes in muscular akinesia and intraocular pressure under peribulbar anaesthesia caused by different volumes of 0.75% bupivacaine with or without the addition of Thiomucase (chondroitin sulphatase) in patients undergoing cataract surgery. A total of 120 patients were randomly allocated into four groups: group 1, bupivacaine 5 mL; group 2, bupivacaine 5 mL plus Thiomucase 10 U mL-1; group 3, bupivacaine 9 mL; group 4, bupivacaine 9 mL plus Thiomucase 10 U mL-1. We assessed: (1) akinesia according to mobility in the four quadrants of the eyeball and the palpebral opening using a scoring system between 0 (total akinesia) and 10 (full movement); and (2) intraocular pressure before, immediately after and 15 min after peribulbar anaesthesia. A significantly better motor blockade was observed in groups 2, 3 and 4 than in group 1 (P < 0.05). Thiomucase increased the quality of motor blockade in group 2, but not in group 4. Intraocular pressure increased by 5-10 mmHg in comparison with baseline values and, after 15 min application of Honan's balloon, decreased by 8-10 mmHg in comparison with baseline values, with no significant differences between groups. Thiomucase can improve the motor block if a lower volume of local anaesthetic is used. The administration of 5 or 9 mL volumes or the addition of Thiomucase decreases the the intraocular pressure in a similar way.
Ortiz
M
M
Department of Anaesthesia, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain.
Blanco
D
D
Serra
J
J
Vidal
F
F
D000368:Aged; D000765:Anesthesia, Conduction; D000779:Anesthetics, Local / Q000008:administration & dosage*; D002045:Bupivacaine / Q000008:administration & dosage*; D002387:Cataract Extraction; D002811:Chondroitinsulfatases / Q000008:administration & dosage; D005123:Eye; D005143:Eyelids / Q000187:drug effects; D005260:Female; D005966:Glucuronidase / Q000008:administration & dosage*; D006801:Humans; D007279:Injections, Subcutaneous; D007429:Intraocular Pressure / Q000187:drug effects*; D008190:Lyases / Q000008:administration & dosage*; D008297:Male; D009068:Movement; D009801:Oculomotor Muscles / Q000187:drug effects*; D009915:Orbit
D000779:Anesthetics, Local; C021812:mucopolysaccharidase; D002811:Chondroitinsulfatases; D005966:Glucuronidase; D008190:Lyases; D002045:Bupivacaine