Risk factors and prevention for perioperative anaphylaxis: a nested case-control study.

Background Perioperative anaphylaxis is rare but often severe. Little is known about the risk factors regarding perioperative anaphylaxis and the effect of anti-allergy premedication on prevention of perioperative anaphylaxis. Objective To identify the risk factors of perioperative anaphylaxis and to evaluate the prophylactic effects of anti-allergy premedication on perioperative anaphylaxis and investigate the factors associated with anti-allergy premedication options in patients who previously experienced anaphylaxis with unidentified culprits. Setting Surgical operation unit of the University Hospital in Chongqing, China. Method We identified patients who underwent surgery between Oct. 2012 and Dec. 2017. The study included two parts: in part one, a retrospective nested case-control study was used to identify the risk factors of perioperative anaphylaxis by logistic regression with 1 in 4 matching between patients with and without perioperative anaphylaxis; in part two, patients with high-risk anaphylaxis were included, in which patients who previously experienced anaphylaxis with unidentified culprits had been given anti-allergy premedication prior to the operation according to the degree of risk and severity of anaphylaxis. The prophylactic effects of anti-allergy premedication were evaluated and the factors associated with anti-allergy premedication options were explored. Main outcome measure Perioperative anaphylaxis occurrence. Results In part one, in the multivariate logistic analysis, history of drug allergy (OR 6.78; 95% CI, 2.35-19.54; P < 0.01) and history of allergies to food or other substances (OR 40.56; 95% CI, 8.12-202.52; P < 0.01) were associated with a higher risk of perioperative anaphylaxis. In part two, none of these patients either who had avoided culprits or who had been given anti-allergy premedication developed anaphylaxis during the surgical procedure. In the multivariate logistic model, history of grade II or grade III perioperative anaphylaxis (OR 9.09; 95% CI, 1.34-61.55; P = 0.02) was identified as factor associated with anti-allergy premedication options in high-risk perioperative anaphylaxis patients. Conclusion In this study, history of drug allergy and history of allergies to food or other substances were significantly associated with perioperative anaphylaxis. Avoiding culprit drugs or taking rational anti-allergy premedication was critical to prevent perioperative anaphylaxis for surgical patients with high-risk factors.