1097. An Antimicrobial Stewardship Intervention to Optimize Cefazolin Dosing for Surgical Prophylaxis

BACKGROUND: Guidelines for antimicrobial prophylaxis in surgery recommend cefazolin dose be adjusted based on patient weight. Adults weighing ≥120 kg should receive a 3 g dose, all other adult patients should receive a 2 g dose pre-operatively. To promote guideline adherence, an antimicrobial stewardship pharmacist-driven dose optimization intervention was implemented. METHODS: Retrospective, pre (February 1, 2017–March 31, 2017)/post (February 1, 2018–March 31, 2018) study evaluating the impact of a pharmacist-driven cefazolin dose optimization intervention at a large health system. An alert within the electronic health record notified pharmacists during order verification when cefazolin dose from a surgical prophylaxis order set did not match weight-based recommendations. All patients with cefazolin orders for surgical prophylaxis were included; pediatric and pregnant patients were excluded. RESULTS: Pre-group included 9,830 patients, post-group 10,025 patients. In both groups, the mean age was 58 years, mean weight 87 kg, and 8% of patients weighed ≥120 kg. Approximately 21% of patients were seen at the academic medical center, 8% at ambulatory surgery centers, and the remainder amongst 10 community hospitals. Most common surgical procedure types were orthopedic (26%), general surgery (21%) and urologic (10%). Primary cefazolin dose was 2 g in 89.8% vs. 88.7%, followed by 3 g 6.6% vs. 6.9% and 1 g in 3.9% vs. 4.4%, pre- and post-intervention, respectively. Overall adherence to weight-based cefazolin dosing was 92.2% pre-group and 92.4% post-group. In patients weighing ≥120 kg, adherence improved from 62% (514/827) to 71% (582/817) post-intervention, P < 0.001. Adherence was better both pre- and post-intervention when an order set was used (pre: order set 95.0% vs. no order set 85.9%, P < 0.001; post: order set 96.4% vs. no order set 84.8%, P < 0.001). There were no differences between surgical services or hospital locations. Investigation of guideline nonadherent cases found order sets without updated dosing recommendations and allowed for targeted education efforts. CONCLUSION: Overall adherence to cefazolin weight-based dosing recommendations for surgical prophylaxis was high, especially with the use of order sets. Pharmacist-driven dose optimization intervention improved guideline adherence in patients weighing ≥120 kg. DISCLOSURES: All authors: No reported disclosures.