摘要目的 探讨眼球居中指导日间门诊眼底检查术早产儿七氟醚吸入麻醉的效果.方法 矫正胎龄(末次月经第1天至接受眼底检查时的周数)为44～64周拟行眼底检查术的早产儿,随机分为2组:体动组和眼球居中组.麻醉诱导:面罩吸入6%七氟醚,氧流量3 L/min,保留自主呼吸.麻醉诱导后使用开眼器撑开眼睑行眼底检查.采用up-and-down法确定麻醉维持期间七氟醚吸入浓度.两组初始维持浓度均为3%,相邻浓度差值为0.5%.计算体动组七氟醚抑制体动反应的半数有效浓度及其95%可信区间[EC50(95%CI)]和眼球居中组七氟醚使眼球居中的EC50(95%CI).记录麻醉维持期间体动或眼球居中情况、最低SpO2、呼吸抑制和呛咳的发生情况.结果 体动组共入选早产儿27例,七氟醚抑制体动反应的EC50(95%CI)为2.9%(2.2%～3.6%),眼球居中组共入选早产儿3例,七氟醚使眼球居中的EC50(95%CI)为3.4%(2.6%～4.6%).眼球居中组EC50高于体动组(P＜0.05).两组均顺利完成眼底检查,未见呼吸抑制和呛咳,清醒后1 h早产儿饮水及喂奶时无呛咳和呕吐发生.最低SpO2比较差异无统计学意义(P＞0.05).体动组眼球居中早产儿8例,均无体动;无体动早产儿14例,其中眼球居中早产儿8例.眼球居中组眼球居中早产儿15例,均无体动;无体动早产儿24例,其中眼球居中早产儿15例.结论 早产儿日间门诊眼底检查术中吸入七氟醚麻醉时适宜应用眼球居中作为判断麻醉深度的标准.

abstractsObjective To investigate the efficacy of centrally fixed eyeball for assessment of the depth of anesthesia in premature infants undergoing outpatient fundus examination. Methods Fifty eight premature infants undergoing examination of fundus of eyes were enrolled in this study. Their gestational age (from the first day of last menstruation period to birth) + after birth age (from birth to the day when examination of fundus of eyes was performed) = 44-64 weeks. The patients were randomly divided into 2 groups: Ⅰ group body movement (group M, n = 27) and Ⅱ group centrally fixed eyeball (group E, n = 31). Anesthesia was induced and maintained with isoflurane inhalation. The patients were breathing spontaneously. The eyelids were kept open with speculum after induction of anesthesia. The EC50 of sevoflurane concentration which could inhibit body movement or make eyeballs centrally fixed was determined by up-and-down sequential experiment. The initial isoflurane concentration was 3% in both groups. Each time the isoflurane concentration was increased/decreased by 0.5 %. 95 % confidence interval (CI) was calculated. The lowest SpO2, respiratory rate and coughing during maintenance of anesthesia were recorded. Results The EC50 of sevoflurane (95% CI) was 2.9% (2.2%-3.6%) in group M and 3.4%(2.6%-4.6%) in group E. Examination was successfully completed in all patients. No respiratory depression and coughing occurred during examination and no vomiting and coughing were observed during feeding at 1 h after recovery from anesthesia. No body movement occurred in 15 patients whose eyeballs were centrally fixed in group E. Conclusion Centrally fixed eyeball can be used as sign of appropriate depth of anesthesia for fundus examination in premature infants.