(1014) Predictors of antibiotic redosing in cesarean deliveries with excessive blood loss

Objective: Surgical site infections occur in up to 15% of patients after cesarean delivery, and elevated blood loss during surgery is associated with postoperative infectious complications. Multiple societies recommend that surgical patients who experience excessive blood loss should receive an additional intraoperative dose of the pre-incision antibiotic. However, these guidelines are not consistently followed. We sought to examine factors associated with receiving a redose of preincision antibiotic in cesarean deliveries with excessive blood loss.

Study Design: A retrospective cohort study of all patients who underwent cesarean delivery at a single site from October 2018 - April 2022 with an estimated or quantitative blood loss > 1.5 liters. Demographic and pregnancy data were abstracted from the electronic medical record. The relationship between blood loss, baseline characteristics, and antibiotic redose was described by univariable analysis. We identified factors associated with antibiotic redose using multivariable logistic regression.

Results: Of 113 patients who met criteria for redose, 35 (31.0%) were given an additional dose of preincision antibiotic. The median blood loss was 2000 mL (IQR 1800 - 3000mL). 44 (38.9%) patients underwent a cesarean hysterectomy. Patients were more likely to receive a redose if they had higher blood loss (p=.0002), cesarean hysterectomy (p< .0001), or delivered at an earlier gestational age (p=.007) (Table). After adjusting for confounders, only cesarean hysterectomy was still an independent predictor of antibiotic redose (aOR 4.56, 95% CI 1.59 - 13.06).

Conclusion: Patients with blood loss > 1.5 liters during cesarean delivery were more likely to receive the recommended redose of preincision antibiotics if they underwent cesarean hysterectomy. Overall compliance with the recommendation to redose antibiotics in cesarean deliveries with excessive blood loss was suboptimal, and measures should be taken to improve redosing in all patients who meet criteria.