Russell S C, Doyle E
Department of Anaesthesia, Royal Hospital for Sick Children, Edinburgh, Scotland.
Drug Saf. 1997 Apr;16(4):279-87. doi: 10.2165/00002018-199716040-00005.
Since its introduction, eutectic lidocaine-prilocaine cream ('EMLA')1 has been found to be an effective topical anaesthetic agent, with a high degree of efficacy, particularly for venepuncture and venous cannulation, and an impressive tolerability profile. Reports of adverse effects are remarkable for their rarity. The only problems that are likely to be encountered are oral ingestion of the cream (which may lead to anaesthesia of the oropharynx and possible toxicity secondary to rapid absorption of local anaesthetic from oral mucous membranes) and methaemoglobinaemia following repeated applications in neonates and infants. Analysis of the risks and benefits associated with its use comes down heavily in favour of the preparation. More recently, a preparation of tetracaine (amethocaine) has been marketed as a gel. Its advantages are a faster onset, and longer duration, of action than 'EMLA'. Although less widely used, it too has an impressive tolerability record. Concerns over the potential for anaphylactic type reactions due to its ester structure have not been realised in clinical practice. Of the other available preparations, lidocaine (lignocaine), applied iontophoretically, is unlikely to become popular because of the complexity of administration. A paste made of tetracaine, epinephrine (adrenaline) and cocaine (TAC) appears to be a far more toxic preparation on theoretical grounds, and this has been borne out in clinical practice; it is not as well tolerated as 'EMLA' or tetracaine gel. Ethyl chloride, although not a local anaesthetic, can safely provide cutaneous analgesia in children in circumstances when it is impractical to wait for a local anaesthetic preparation to take effect.
自引入以来，复方利多卡因乳膏（“EMLA”）1已被发现是一种有效的局部麻醉剂，具有高度的有效性，特别是在静脉穿刺和静脉插管方面，并且耐受性良好。不良反应的报告非常罕见。可能遇到的唯一问题是口服该乳膏（这可能导致口咽麻醉，并可能因局部麻醉剂从口腔黏膜快速吸收而产生毒性）以及新生儿和婴儿反复使用后出现高铁血红蛋白血症。对其使用相关风险和益处的分析强烈支持该制剂。最近，丁卡因（阿美卡因）制剂已作为凝胶上市。它的优点是起效比“EMLA”更快，作用持续时间更长。虽然使用不太广泛，但它也有令人印象深刻的耐受性记录。由于其酯结构，对其潜在过敏反应类型的担忧在临床实践中尚未出现。在其他可用制剂中，离子导入法应用的利多卡因（利多卡因）由于给药复杂，不太可能流行。由丁卡因、肾上腺素（肾上腺素）和可卡因（TAC）制成的糊剂从理论上讲似乎毒性更大，这在临床实践中得到了证实；它的耐受性不如“EMLA”或丁卡因凝胶。氯乙烷虽然不是局部麻醉剂，但在等待局部麻醉制剂起效不切实际的情况下，可以安全地为儿童提供皮肤镇痛。
