Gonzalez-Estrada A, Carrillo-Martin I, Renew JR, et al. - Researchers investigated the incidence of perioperative anaphylaxis (PA) in the United States using de-identified data from the Nationwide Inpatient Sample from 2005 to 2014. In addition, they compared patient characteristics and underlying risk factors. Among 35,647,347 assessed surgeries and procedures, 5,458 (0.015%) PA cases were identified. PA incidence is 1 in 6,531 procedures with a mortality of 1 in 191,652 procedures. Worsened outcomes were reported among those with PA vs controls. Risk factors of PA include age 18-34 years; female gender; transplant, hematologic, vascular, and cardiac procedures; and several comorbidities including chronic pulmonary disease.