过敏反应
患者若意外摄取过敏性食物并出现过敏反应症状应及时肌注肾上腺素和抗组胺药。延迟使用肾上腺素会导致致命的结果。皮肤症状如瘙痒或荨麻疹往往不出现在食物引起的过敏反应中,会使识别难度加大。[16]Bock SA, Muñoz-Furlong A, Sampson HA. Fatalities due to anaphylactic reactions to foods. J Allergy Clin Immunol. 2001;107:191-193.http://www.ncbi.nlm.nih.gov/pubmed/11150011?tool=bestpractice.com[35]Yun J, Katelaris CH. Food allergy in adolescents and adults. Intern Med J. 2009;39:475-478.http://www.ncbi.nlm.nih.gov/pubmed/19382983?tool=bestpractice.com如果患者有喉咙发紧、播散性荨麻疹、口咽血管性水肿、声嘶、喘鸣、低血压或反复呕吐等任何症状,应当立即给予肾上腺素。[36]National Institute for Health and Care Excellence. Anaphylaxis: assessment to confirm an anaphylactic episode and the decision to refer after emergency treatment for a suspected anaphylactic episode. December 2011. http://www.nice.org.uk/ (last accessed 11 August 2016).http://www.nice.org.uk/guidance/CG134
如果在医疗环境之外发生过敏,可给予患者2个剂量的肾上腺素自动注射器,用于即刻使用。对于成人和儿童,医生应开具 2 支肾上腺素自动注射器。[37]Lieberman P, Nicklas RA, Randolph C, et al. Anaphylaxis--a practice parameter update 2015. Ann Allergy Asthma Immunol. 2015;115:341-84.http://www.ncbi.nlm.nih.gov/pubmed/26505932?tool=bestpractice.com患者应接受医生有关如何使用肾上腺素自动注射器的指导。如果患者确实使用了一支或多支肾上腺素自动注射器治疗严重过敏反应,应当告诉他们立即就医。
肾上腺素使用的延迟也与双相反应相关,患者在初步缓解后又出现症状复发。因此,对于过敏反应的患者,经治疗后症状得到缓解时,不能立即出院,而是应该密切观察8到24小时防止症状复发。[36]National Institute for Health and Care Excellence. Anaphylaxis: assessment to confirm an anaphylactic episode and the decision to refer after emergency treatment for a suspected anaphylactic episode. December 2011. http://www.nice.org.uk/ (last accessed 11 August 2016).http://www.nice.org.uk/guidance/CG134
对于哮喘患者、对花生或坚果过敏患者,以及青少年来说,因食物过敏而引发致命过敏反应的风险会增加。[38]Sampson HA. Fatal food-induced anaphylaxis. Allergy. 1998;53(suppl 46):125-130.http://www.ncbi.nlm.nih.gov/pubmed/9826019?tool=bestpractice.com[39]Shah E, Pongracic J. Food-induced anaphylaxis: who, what, why, and where? Pediatr Ann. 2008;37:536-541.http://www.ncbi.nlm.nih.gov/pubmed/18751571?tool=bestpractice.com对于青少年而言,致命性严重过敏反应的发生,部分上是由于故意食用过敏食物和/或不携带其肾上腺素自动注射器等冒险行为所致。