Standardized diagnosis results of suspected local anesthetics allergy

Abstract

To review and investigate the diagnosis results of local anesthetics (LA) allergy and improve the understanding of LA allergy in clinician. From March 2017 to February 2022, a total of 24 patients were investigated in Allergy Center of West China Hospital,Sichuan University on suspicion of LA allergy. Clinical data and results of skin tests and drug provocation tests (DPT) with the suspected drugs were retrospectively evaluated. The value of standardized diagnostic protocol in the LA allergy were analyzed. The results showed that 24 patients (3 men/21 women) were included with age range from 20 to 74 years. Three cases (12.5%) were positive in previous LA skin tests and proved to be tolerated through standardized tests. Twenty-one patients were initially diagnosed as "LA allergy" because of adverse reactions after previous use of LA, including 20 cases of immediate-type reaction and 1 case of delayed-type reaction. Three cases were considered LA allergy through standardized diagnosis approaches, including skin tests and DPT. One patient was diagnosed with anaphylaxis caused by chlorhexidine. Of the remaining 17 patients, 7 were considered as psychosomatic reactions (29.1%), 3 of sympathetic nervous system conditions (12.5%), 1 of spontaneous urticaria (4.2%), 2 of vasovagal syncope (8.3%), drug side effects (8.3%), skin irritation (8.3%), respectively. In conclusion, true allergic reactions to LA are rare. Through standardized skin tests and DPT, allergy can be ruled out in the vast majority of patients who complain of "LA allergy". For patients who are highly suspected of LA inducing anaphylaxis, other local anesthetics that can be used as safe alternatives should be determined by diagnostic tests according to future needs.