Anatomy of a successful stewardship intervention: Improving perioperative prescribing in penicillin-allergic patients

Quality corner: Safely using cephalosporins in almost all patients with penicillin allergies: Mini-review and suggested protocol to improve efficacy and surgical outcomes

Surgical site infections (SSI) are one of the most common gynecologic oncology postoperative complications and they have a significant deleterious impact on the healthcare system and in patients' outcomes. Cefazolin is the recommended antibiotic in women undergoing gynecologic surgical procedures that require that require prophylaxis. However, 10-20% of patients may report a penicillin allergy which can result in administration of a less effective antibiotic. This quality review evaluated the literature around this common perioperative issue and demonstrated that healthcare teams should consider the implementation of a protocol to safely use cefazolin in most patients with a penicillin allergy. Overall, literature shows this is a safe adjustment and would improve antimicrobial stewardship, decrease SSI rates, avoid acute kidney injury, and increase cost savings.

Management of Penicillin Allergy in the Perioperative Setting

The selection of perioperative antibiotic prophylaxis is challenging in patients with a history of penicillin allergy; as such, we present a literature review exploring current best practices and the associated supporting evidence, as well as areas for future research. Guidelines recommend the use of alternative agents in patients with an IgE-mediated hypersensitivity reaction, but those alternative agents are associated with worse outcomes, including an increased risk of surgical site infection, and higher cost. More recent data suggest that the risk of cross-reactivity between penicillins and cephalosporins, particularly cefazolin, is extremely low, and that cefazolin can be used safely in most penicillin-allergic patients. Studies have therefore explored how best to implement first-line cefazolin use in patients with a penicillin allergy label. A variety of interventions, including preoperative allergy de-labeling with incorporation of penicillin skin testing, use of patient risk-stratification questionnaires, and utilization of clinician algorithms to guide antibiotic selection intraoperatively, have all been shown to significantly increase cefazolin utilization without a corresponding increase in adverse events. Further studies are needed to clarify the most effective interventions and implementation strategies, as well as to evaluate whether patients with severe delayed hypersensitivity reactions to penicillin should continue to be excluded from receipt of other beta-lactams.

Impact of a Pharmacist-Conducted Preoperative Beta-Lactam Allergy Assessment on Perioperative Cefazolin Prescribing

Background: Cefazolin is guideline recommended for perioperative prophylaxis in orthopedic surgery. Despite its unique R1 side chain, cefazolin is often avoided in patients with beta-lactam allergy with concern for cross reactivity. Objectives: The primary outcome was the percentage of patients who received cefazolin perioperatively. Secondary outcomes included the percentage of patients with a beta-lactam allergy clarified following the telephone interview and clinical outcomes including acute kidney injury, surgical site infection, Clostridioides difficile infection, and re-admission at 30 and 90 days. Methods: This single-center, quasi-experimental study evaluated a pilot program in which a pharmacist phoned patients > 18 years of age with a scheduled orthopedic surgery and a documented beta-lactam allergy to assess their allergy preoperatively. Recommendations to use cefazolin were based on an algorithm. Patients were divided into pre- and post-intervention cohorts. Results: A total of 832 patients were screened for inclusion with 135 and 66 patients included in the pre- and post-intervention cohorts. No significant difference was identified in the primary outcome. In the post-intervention cohort, 62% had a beta-lactam reaction updated in the electronic medical record. Those with a beta-lactam allergy delabeled or made less severe were numerically more likely to receive cefazolin than those with an unchanged reaction or a reaction made more severe (95.2% vs 68% vs 65%). There were no differences in clinical outcomes between groups. Conclusion: A pharmacist-conducted preoperative beta-lactam allergy interview in adult patients undergoing elective orthopedic surgery improved beta-lactam allergy documentation but, did not result in increased utilization of cefazolin.

Penicillin Allergy and Perioperative Anaphylaxis

Penicillin allergy is the most commonly reported drug allergy, while perioperative anaphylaxis is overall rare. This review covers the epidemiology of both penicillin allergy and perioperative anaphylaxis both separately and taken together. Considerations regarding anaphylaxis to penicillin during pregnancy are also discussed, since penicillin is the drug of choice for Group B Streptococcus prophylaxis. The minimal cross reactivity between penicillins and cephalosporins is addressed, since the vast majority of patients with a penicillin allergy label can receive perioperative cephalosporins. The management of the patient who has experienced perioperative anaphylaxis, including the importance of allergy referral is covered. Approaches to pre-operative penicillin allergy evaluations and opportunities for education are highlighted.