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Optimizing Cefazolin Prophylaxis in Obstetrical Patients with Reported Beta-Lactam Allergy Undergoing Cesarean
Helen Genis1, Melinda Li2, Melanee Eng-Chong3
1Department of Medicine, University of Toronto, Toronto, ON.
Objectives:
Evaluate the impact of an allergy history-guided algorithm for optimizing perioperative cefazolin use in patients with reported beta-lactam allergy undergoing cesarean delivery.
Methods:
The Allergy Clarification for Cefazolin Evidence-based Prescribing Tool (ACCEPT) was developed through consensus by allergists, anesthesiologists, and infectious diseases specialists, and implemented over a 2-month period (December 1, 2018, to January 31, 2019). A segmented regression on monthly cefazolin use was conducted during the baseline (January 1 to November 30, 2018) and intervention (February 1 to December 31, 2019) periods to evaluate the impact of ACCEPT on the monthly use of perioperative cefazolin in patients with reported beta-lactam allergy undergoing cesarean delivery. The frequency of perioperative allergic reactions and surgical site infections was collected during both periods.
Results:
Of the 3128 eligible women who underwent a cesarean delivery, 282 (9%) reported a beta-lactam allergy. The most common beta-lactam allergens were penicillin (64.3%), amoxicillin (16.0%), and cefaclor (6.0%). The most frequently reported allergic reactions were rash (38.1%), hives (21.4%), and unknown (11.6%). Use of cefazolin increased from 52% (baseline) to 87% during the intervention period. Segmented regression analysis confirmed a statistically significant increase following implementation (incidence rate ratio 1.62, 95% CI 1.19-2.21, P = 0.002). There was 1 perioperative allergic reaction in the baseline period and 2 during the intervention period. Cefazolin use remained high (92%) 2 years after algorithm implementation.
Conclusions:
Implementation of a simple allergy history-guided algorithm in obstetrical patients with reported beta-lactam allergy resulted in a sustained increase in perioperative cefazolin prophylaxis.
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