Efficacy and safety of three ophthalmic inserts for topical anaesthesia of the cornea. An exploratory comparative dose-ranging, double-blind, randomized trial in healthy volunteers.

BACKGROUND: Cataract surgery requires prolonged anaesthesia, concomitant with permanent hydration and lubrication of the cornea, in order to provide a clear view of the operation area. AIMS: The primary objective of the study was to assess several formulae of a soluble ophthalmic insert: TOPICSERT [bupivacaine (Bupi) + hyaluronic acid (HA) or sodium hyaluronate] in terms of complete and long-lasting anaesthesia of the cornea. The hydration properties of HA were not assessed in this study. METHODS: In a prospective double-blind, cross-over, randomized study, with latin-square allocation of treatments, 16 healthy volunteers received a single dose of each formula (A, 1 mg Bupi and 0.1 mg HA; B, 0.5 mg Bupi and 0.1 mg HA; C, 1 mg Bupi and 0 mg HA, and D acting as a placebo) via the ocular route with 1 week of wash-out between each period. Corneal anaesthesia was measured using a Cochet-Bonnet esthesiometer. RESULTS: There was a statistically significant difference between treatments with regard to the main criterion (complete anaesthesia lasting at least 20 min) when general association statistics were used (Mantel-Haenzel test, P < 0.0001): 68.75% (n = 11) of subjects receiving treatment A, 37.5% (n = 6) receiving treatment B, and 87.5% (n = 14) on treatment C reached complete and satisfactory anaesthesia, while this was not achieved in any of the subjects receiving placebo. Ninety-five percent confidence intervals of the difference between treatments were as follows: treatment A vs. B (-0.03, 0.66), treatment A vs. C (-0.47, 0.10), treatment B vs. C (-0.84, - 0.16). Only the difference between B and C was statistically significant (adjusted probability by the method of Bonferroni, P < 0.001). When complete anaesthesia was reached, mean (+/-SD) duration of anaesthesia was as follows: 20.7 (+/-6.5), 15.3 (+/-11.4) and 24.7 (+/-7.6) min for treatments A, B, C, respectively. CONCLUSIONS: Bupivacaine 1 mg seems to be the efficient and safe dose. The value of hyaluronic acid as a corneal hydration agent and used in association with bupivacaine will be the subject of further studies.

Ureteroscopias: aspectos críticos das complicaçöes / Ureteroscopy: critical aspects of complications

Avaliamos retrospectivamente 319 ureteroscopias rígidas realizadas em 316 pacientes entre junho de 1987 e dezembro de 1994, atendendo-se à incidência de complicaçöes e seus respectivos tratamentos. Ocorreram complicaçöes intra-operatórias em 50 procedimentos (15, 67 por cento), sendo 34 casos de perfuraçäo de ureter (10,65 por cento), 15 de laceraçäo de mucosa (4,7 por cento) e um de desinserçäo do ureter distal (0,31 por cento). Diagnosticamos complicaçöes tardias em 12 casos (3,76 por cento), ocorrendo estenose de ureter em seis pacientes (1,88 por cento), estenose de ureta em três (0,31 por cento). Os pacientes com laceraçöesmínimas de mucosa foram tratados apenas com cateterismo uretal por 24 a 36 horas, porém, nos casos em que ocorreram laceraçöes mais importantes ou perfuraçäo uretal, com maior extravasamento de urina e soluçäo salina, optou-se por colocaçäo de cateter de duplo J por 30 a 90 dias. Em um caso em que ocorreu avulsäo de ureter realizou-se reimplante ureteral. Os casos que evoluíram com estenose tardia de ureter foram tratados com sucesso com dilataçäo ureteral com baläo (5 casos) ou reimplante ureteral (1 caso). Os três casos de estenose de uretra foram tratados com uretrotomia interna com faca de Sachse, evoluindo sem complicaçöes. Concluímos que nos casos de perfuraçäo ureteral o cateterismo prolongado com cateter de duplo J é o tratamento de escolha, sendo seguro e com baixa incidência de complicaçöes tardias. Nos procedimentos em que ocorreram laceraçöes de mucosa, cateterismo ureteral por 24 a 36 horas é suficiente para tratar a lesäo. A ureteroscopia, portanto, mostrou-se um método eficiente de tratamento de cálculos ureterais do terço inferior do ureter com baixo índice de complicaçöes