局所麻酔薬，抗菌薬とアレルギーの総説

Local Anesthetics, Antibiotics, and Allergy

はじめに

　局所麻酔薬による有害事象は，心因反応（迷走神経反射），局所麻酔薬中毒（中枢神経系，心毒性），添加アドレナリンによるもの，アレルギー反応（遅延型アレルギー性皮膚炎，アナフィラキシー），メトヘモグロビン血症が挙げられる。周術期では局所麻酔薬中毒やアレルギー反応が多い。

　抗菌薬による有害事象は，腎障害，耳毒性，神経・筋接合部障害，中枢・末梢神経障害，血液凝固障害，アレルギー反応（遅延型アレルギー性皮膚炎，アナフィラキシー）が挙げられる。周術期ではアレルギー反応が主で即時型が多い。一番の問題となるのはアレルギー反応の中で最も重症度が高い病態であるアナフィラキシーである^1）～3）。海外の報告では全身麻酔症例1-2万症例に1症例程度の確率（0.005-0.01％）でアナフィラキシーが発生し，死亡率は3-9％と報告されている^4）。日本の調査でも発症率は0.01％（1万症例に1症例），死亡率は4.76％と報告されている^5）。したがって手術件数が年間数千-1万件の医療機関の場合，周術期アナフィラキシーは2-4年に1症例程度は発生する可能性がある^6）。麻酔科医として生涯遭遇する可能性があり，対応や治療について熟知する必要がある。本論文では周術期における局所麻酔薬と抗菌薬の有害事象と，それらに対する対応・治療について概説する。

　The adverse events that can be caused by local anesthetics include psychogenic reactions（e.g., vagal reflex）, local anesthetic intoxication（e.g., central nervous system effects, cardiotoxicity）, additive adrenaline, allergic reactions（e.g., delayed allergic dermatitis, anaphylaxis）, and methemoglobinemia. Local anesthetic intoxication and allergic reactions are common when local anesthetics are administered during the perioperative period. The adverse events that are associated with antibiotics include renal impairment, ototoxicity, neuromuscular junction disorders, central and peripheral neuropathy, blood clotting disorders, and allergic reactions（e.g., delayed allergic dermatitis, anaphylaxis）.

　The most frequent allergic reaction that occurs when antibiotics are administered during the perioperative period is anaphylaxis, which is also the most severe of the several types of allergic reactions. According to overseas reports, among all surgery cases, anaphylaxis occurs in approx. 0.005％-0.01％ and the rate of mortality due to anaphylaxis is 3％-9％. In Japan, the corresponding values are 0.01％ and a 4.76％ mortality rate. At medical institutions that conduct thousands of surgeries per year, perioperative anaphylaxis may therefore occur in at least one case per year. As an anesthesiologist, you may encounter anaphylaxis and other adverse events due to a local anesthetic or antibiotic treatment sometime over the course of your career, and you need to be thoroughly familiar with the appropriate medical responses and treatments. This chapter outlines adverse events that are associated with local anesthetic and antibiotic use in the perioperative period, as well as the responses to and treatments of adverse events.