Safety and effectiveness of a preoperative allergy clinic in decreasing vancomycin use in patients with a history of penicillin allergy

Background: We developed a clinical pathway to optimize the use of antimicrobials by decreasing vancomycin use in preoperative patients with a history of penicillin allergy. Objective: To decrease the use of vancomycin in surgical patients with a self-reported penicillin allergy. Methods: In June 2002, same-day allergy consultation and penicillin skin testing were made available for preoperative patients with self-reported penicillin allergy at the preoperative evaluation (POE) clinic. We reviewed the penicillin allergy skin test results, recommendations, and β-lactam antibiotic administration outcomes from July 1, 2002, to September 16, 2003. Results: A total of 1,204 of 11,819 patients were evaluated for β-lactam allergy at the POE clinic. Of these, 1,120 were approved by the institutional review board for inclusion in the study and 9 were excluded from the study. Of the remaining 1,111 patients, 1,030 (93%) underwent skin testing for penicillin allergy. Forty-three (4%) had a positive skin test result to penicillin. A total of 947 (85%) of the 1,111 patients with a history of β-lactam allergy were advised to use a β-lactam antibiotic, and 164 (15%) were advised to avoid β-lactams. A total of 955 patients (86%) actually received preoperative antibiotics. Of these 955 patients, 716 (75%) received cefazolin, and only 149 (16%) received vancomycin compared with 30% historical controls (P < .01). Among the patients with a negative penicillin skin test result who received a cephalosporin, 5 (0.7%) of 675 experienced an adverse drug reaction to a cephalosporin. Conclusions: Establishment of a clinical pathway in a preoperative clinic that includes allergy consultation and penicillin skin testing reduced vancomycin use to only 16% in surgical patients with a history of β-lactam allergy.