A Rare Case of Euphoria Caused by Lidocaine After an Erector Spinae Plane Block: A Case Report

Joo Yong Lee, Hyeon Tae Kim, Jeong Moon Won, Young Duck Shin Department of Anesthesiology and Pain Medicine, Chungbuk National University Hospital, College of Medicine, Chungbuk National University, Cheongju, KoreaCorrespondence: Young Duck Shin; Hyeon Tae KimDepartment of Anesthesiology and Pain Medicine, Chungbuk National University Hospital, 776, 1 Sunhwan-Ro, Seowon-Gu, Cheongju, Chungbuk 28644, KoreaTel +82-43-269-6234; +82-43-269-6988Fax +82-43-272-0264Email yydshin@naver.com; gskht@naver.comAbstract: Lidocaine is a cost-effective drug that is widely used for local and regional anesthesia. However, central nervous system (CNS) toxicity can occur when lidocaine is administered above the maximum recommended dose (approximately 4.5 mg/kg) or if lidocaine is injected intravascularly rather than administered locally. Systemic toxicity by lidocaine has been reported in several studies. However, psychotic reactions due to lidocaine have been rarely reported; furthermore, reports of lidocaine-related euphoria are very rare. We report a very rare case of euphoria caused by CNS toxicity that occurred during the local administration of lidocaine at the therapeutic dose. Therefore, anesthesiologists should be aware of the severe side effects of local anesthetics despite administering the appropriate dosage at the appropriate location. Future studies should investigate pharmacokinetics to determine the safety profile of local anesthetics.Keywords: euphoria, lidocaine, adverse effects, nerve block