目的：分析比较3mL和5mL利多卡因眼球筋膜囊下麻醉对白内障超声乳化手术中眼压，镇痛效果和眼外肌失运动能力的作用效果。眼球筋膜囊下麻醉是白内障超声乳化术中常用的局麻方式。作为一种剂量依赖型的阻滞方式，良好的眼压、镇痛效果以及眼外肌失运动是手术成功需要考虑的重要因素。

方法：在获得伦理批准和患者的知情同意后，随机纳入70例患者作为研究对象，分别给予3mL利多卡因(组一)和5mL利多卡因(组二)作眼球筋膜囊下麻醉。麻醉前测量眼压，麻醉后10min评估眼压，镇痛效果和眼外肌失运动能力，并记录球结膜水肿和结膜下出血等并发症。

结果：在麻醉管理期间，由于两名患者要求镇静，故从本研究中排除。比较组内及组间患者在麻醉前、后的基本特征，如年龄、体质量、身高、眼轴长度以及ASA生理状态，均无明显差异。与组一相比，组二患者眼外肌失运动能力及镇痛效果均明显较好。组二中有13例患者(38.2%)可达到眼球完全不运动，而组一没有患者可达到该程度。组一中有18例患者(56.3%)术中完全无痛觉，14例患者(43.7%)存在轻微痛觉，组二中有28例患者(82.4%)无痛觉，6例患者(17.6%)术中有轻微痛觉。此外，两组患者在麻醉前与麻醉后10min，其眼压的变化均无统计学差异(P<0.05)。两组患者并发症发生情况无明显差异。

结论：3mL利多卡因和5mL利多卡因作眼球筋膜囊下麻醉对眼压均无影响，但在白内障超声乳化手术中给予5mL利多卡因作麻醉，在镇痛及眼外肌失运动能方面效果更好。

AIM: To compare the effect of sub-Tenon anesthesia 3 mL and 5 mL lidocaine on intraocular pressure(IOP), analgesia and akinesia. Sub-Tenon's anaesthesia is a common regional technique for cataract surgery by phacoemulsification. As a volume-based block, IOP optimization along with analgesia and akinesia is a concern for successful surgical course.

METHODS: After obtaining ethics approval and informed consent of patients, 70 patients were randomly enrolled to the study to receive sub-Tenon's block with either 3 mL(Group I)or 5 mL(Group II)lidocaine. IOP was measured before the block. IOP, analgesia and akinesia were evaluated at 10min after the block. Complications such as chemosis and subconjunctival hemorrhage were also noted.

RESULTS: Two patients were excluded from the study due to the patients' request for sedation during block administration. Patients' characteristics such as age, weight, height, axial length, American Society of Anesthesiology(ASA)physical status were comparable in-group before and after block measurement and between groups. Akinesia and analgesia were significantly better in Group II in comparison to Group I. “No eye movement” was obtained in 13 patients(38.2%)in Group II whereas none of the patients had “no eye movement” in Group I. Eighteen(56.3%)patients had “no pain” and 14(43.7%)patients had “mild pain” in Group I whereas “No pain” in 28 patients(82.4%)and “mild pain” in 6 patients(17.6%)was observed in Group II. On the other hand, IOP revealed no statistically significant alteration in both groups before and 10min after the block(P<0.05). Complications were comparable between groups.

CONCLUSION: Sub-Tenon's anaesthesia either with 3 or 5 mL lidocaine had no effects on IOP; on the other hand, analgesia and akinesia were preferably better in patients who received 5 mL lidocaine for the block during cataract surgery by phacoemulsification.