Kopecky E A, Jacobson S, Bch M B, Hubley P, Palozzi L, Clarke H M, Koren G
Division of Clinial Pharmacology and Toxicology, Hospital for Sick Children, University of Toronto, Canada.
J Burn Care Rehabil. 2001 May-Jun;22(3):235-42. doi: 10.1097/00004630-200105000-00010.
The purpose of this study was to determine the safety and pharmacokinetics of a eutectic mixture of local anesthetics (EMLA) used to ameliorate postburn pruritus after application onto newly formed, intact skin in children. EMLA was applied once to an itchy site where healed skin had formed. Serial blood samples were collected to measure lidocaine, prilocaine, o-toluidine, and methemoglobin. Maximal plasma concentration, minimal plasma concentration, time to achieve the maximal plasma concentration, elimination half-life, and area under the concentration-time curve were calculated. Vital signs, oxygen saturation, clinical signs of hypoxia, and itch intensity were measured. Five children had 15.7 +/- 2.54 g (+/- SD) of EMLA applied to a skin surface area of 93.0 +/- 37.0 cm2. Lidocaine and prilocaine concentrations were below toxic levels; o-toluidine was not detected. Methemoglobin remained between 1 and 3%; patients did not exhibit any clinical signs of hypoxia. Mean oxygen saturation was 98.9 +/- 0.01%. The mean number of pruritic episodes and antihistamine breakthrough doses were greater in the 2 prestudy control days compared with study day 3 (P = 0.01 and P = 0.03, respectively). Skin at the site of EMLA application remained anesthetized for 12 to 13 hours. In this small pilot study, EMLA seems to be a safe, novel treatment for postburn pruritus in burned children when applied to newly healed, intact skin.
本研究的目的是确定局部麻醉药的共晶混合物（EMLA）在应用于儿童新形成的完整皮肤后用于缓解烧伤后瘙痒的安全性和药代动力学。将EMLA应用于已形成愈合皮肤的瘙痒部位一次。采集系列血样以测定利多卡因、丙胺卡因、邻甲苯胺和高铁血红蛋白。计算最大血浆浓度、最小血浆浓度、达到最大血浆浓度的时间、消除半衰期和浓度-时间曲线下面积。测量生命体征、血氧饱和度、缺氧的临床体征和瘙痒强度。5名儿童在93.0±37.0 cm²的皮肤表面积上涂抹了15.7±2.54 g（±标准差）的EMLA。利多卡因和丙胺卡因浓度低于中毒水平；未检测到邻甲苯胺。高铁血红蛋白维持在1%至3%之间；患者未表现出任何缺氧的临床体征。平均血氧饱和度为98.9±0.01%。与研究第3天相比，在研究前的2个对照日，瘙痒发作的平均次数和抗组胺药突破剂量更多（分别为P = 0.
