Taddio A, Stevens B, Craig K, Rastogi P, Ben-David S, Shennan A, Mulligan P, Koren G
Department of Paediatrics, Hospital for Sick Children, Toronto, ON, Canada.
N Engl J Med. 1997 Apr 24;336(17):1197-201. doi: 10.1056/NEJM199704243361701.
Neonatal circumcision is a painful surgical procedure often performed without analgesia. We assessed the efficacy and safety of 5 percent lidocaine-prilocaine cream (Emla) in neonates undergoing circumcision.
We carried out a double-blind, randomized, controlled trial in 68 full-term male neonates: 38 were assigned to receive lidocaine-prilocaine cream, and 30 to receive placebo. One gram of lidocaine-prilocaine or placebo cream was applied to the penis under an occlusive dressing for 60 to 80 minutes before circumcision. Behavioral (facial activity and time spent crying) and physiologic (heart rate and blood pressure) responses were recorded during the procedure. Blood samples were obtained at various times after drug application for measurements of methemoglobin and plasma lidocaine, prilocaine, and o-toluidine (a metabolite of prilocaine).
A total of 68 and 59 neonates were included in the safety and efficacy analyses, respectively. Demographic characteristics such as gestational age and birth weight did not differ between the lidocaine-prilocaine and placebo groups. During circumcision, the neonates in the lidocaine-prilocaine group had less facial activity (P= 0.01), spent less time crying (P<0.001), and had smaller increases in heart rate (P=0.007) than the neonates in the placebo group. Facial-activity scores were 12 to 49 percent lower during various steps of the procedure in the lidocaine-prilocaine group. As compared with neonates in the placebo group, infants in the lidocaine-prilocaine group cried less than half as much and had heart-rate increases of 10 beats per minute less. Blood methemoglobin concentrations (expressed as a percentage of the hemoglobin concentration) were similar (1.3 percent) in both groups. Lidocaine and prilocaine were detected in plasma in 23 (61 percent) and 21 (55 percent) of the infants treated with lidocaine-prilocaine cream, respectively.
Lidocaine-prilocaine cream is efficacious and safe for the prevention of pain from circumcision in neonates.
新生儿包皮环切术是一种常在未实施镇痛情况下进行的痛苦外科手术。我们评估了5%利多卡因-丙胺卡因乳膏（复方利多卡因乳膏）在接受包皮环切术的新生儿中的有效性和安全性。
我们对68名足月男婴进行了一项双盲、随机、对照试验：38名被分配接受利多卡因-丙胺卡因乳膏，30名接受安慰剂。在包皮环切术前，将1克利多卡因-丙胺卡因或安慰剂乳膏在封闭敷料下涂抹于阴茎60至80分钟。在手术过程中记录行为（面部活动和哭闹时间）和生理（心率和血压）反应。在用药后的不同时间采集血样，以测定高铁血红蛋白以及血浆中的利多卡因、丙胺卡因和邻甲苯胺（丙胺卡因的一种代谢物）。
分别有68名和59名新生儿纳入安全性和有效性分析。利多卡因-丙胺卡因组和安慰剂组在胎龄和出生体重等人口统计学特征方面无差异。在包皮环切术中，利多卡因-丙胺卡因组的新生儿面部活动较少（P = 0.01），哭闹时间较短（P<0.001），心率升高幅度较小（P = 0.007），均低于安慰剂组的新生儿。在手术的各个步骤中，利多卡因-丙胺卡因组的面部活动评分低12%至49%。与安慰剂组的新生儿相比，利多卡因-丙胺卡因组的婴儿哭闹次数减少一半以上，心率增加每分钟少10次。两组的血液高铁血红蛋白浓度（以血红蛋白浓度的百分比表示）相似（1.3%）。在接受利多卡因-丙胺卡因乳膏治疗的婴儿中，分别有23名（61%）和21名（55%）的血浆中检测到利多卡因和丙胺卡因。
利多卡因-丙胺卡因乳膏对预防新生儿包皮环切术疼痛有效且安全。
