Morcos S K
Department of Diagnostic Imaging, Northern General Hospital, Sheffield Teaching Hospitals NHS Trust, Sheffield S5 7AU, UK.
Br J Radiol. 2005 Aug;78(932):686-93. doi: 10.1259/bjr/26301414.
Serious or fatal reactions to a contrast medium (CM) are unpredictable but fortunately rare. History of serious reaction to CM, bronchial asthma or multiple allergies increases the incidence of serious reactions by a factor of 5. Serious or fatal reaction to CM could be due to direct effect on basophils and mast cells or IgE mediated (type 1 hypersensitivity reaction). Activation of the kinin system leading to the formation of bradykinin could also be involved. Complement activation is unlikely to be a primary factor in initiating a serious reaction to CM. Avoiding CM administration in patients at high risk of serious reaction is advisable, but if the administration is deemed essential all precautions should be implemented and measures to treat serious reactions should be readily available. Oxygen supplementation, intravenous administration of physiological fluids and intramuscular injection of 0.5 ml adrenalin (1:1000) should be considered in the first line management of acute anaphylaxis. The ability to assess and treat serious CM reaction effectively is an essential skill that the radiologist should have and maintain.
对比剂(CM)引起的严重或致命反应不可预测,但幸运的是较为罕见。有CM严重反应史、支气管哮喘或多种过敏史会使严重反应的发生率增加5倍。CM引起的严重或致命反应可能是由于对嗜碱性粒细胞和肥大细胞的直接作用或IgE介导(1型超敏反应)。激肽系统的激活导致缓激肽的形成也可能参与其中。补体激活不太可能是引发CM严重反应的主要因素。建议避免在有严重反应高风险的患者中使用CM,但如果认为使用必不可少,则应采取所有预防措施,并随时准备好治疗严重反应的措施。在急性过敏反应的一线处理中,应考虑补充氧气、静脉注射生理盐水和肌肉注射0.5毫升肾上腺素(1:1000)。有效评估和治疗CM严重反应的能力是放射科医生应具备并保持的一项基本技能。