Behndig A, Lindén C
Department of Ophthalmology, Umeå University Hospital, Sweden.
J Cataract Refract Surg. 1998 Dec;24(12):1598-601. doi: 10.1016/s0886-3350(98)80349-0.
To assess aqueous humor lidocaine concentrations in 2 common regimens of topical anesthesia and after intracameral injection of the anesthetic agent.
University hospital eye clinic.
Twenty patients having routine cataract surgery were randomized into 3 groups: 1 given 3 drops of lidocaine 4% before surgery; 1 given 6 drops; 1 given 3 drops plus an intracameral injection of 0.1 mL lidocaine 1%. Lidocaine concentration was measured in aqueous humor samples taken before surgery.
With 3 drops, aqueous lidocaine concentration was 1.4 micrograms/mL +/- 0.5 (SD) and with 6 drops, 4.3 +/- 1.5 micrograms/mL (P = .0015). With an intracameral injection, it was 341.8 +/- 152.6 micrograms/mL.
Measurable amounts of lidocaine entered the anterior chamber in topical anesthesia, and more entered when more drops were given. It is likely that concentrations in this range could anesthetize the iris, but they are far lower than concentrations after an intracameral injection.
评估两种常见局部麻醉方案以及前房内注射麻醉剂后房水中利多卡因的浓度。
大学医院眼科诊所。
20例行常规白内障手术的患者被随机分为3组：1组术前滴3滴4%利多卡因；1组滴6滴；1组滴3滴并在前房内注射0.1 mL 1%利多卡因。在术前采集的房水样本中测量利多卡因浓度。
滴3滴时，房水利多卡因浓度为1.4微克/毫升±0.5（标准差），滴6滴时为4.3±1.5微克/毫升（P = 0.0015）。前房内注射时，浓度为341.8±152.6微克/毫升。
局部麻醉时可测量量的利多卡因进入前房，滴入更多滴时进入量更多。此范围内的浓度可能会麻醉虹膜，但远低于前房内注射后的浓度。
