FFP:RBC ratio, surgery category, and 30-day survival in intraoperative MT meeting concurrent volume and rate criteria: An exploratory study

Massive transfusion (MT) protocols often rely on fresh frozen plasma (FFP) to red blood cell (RBC) ratios, yet optimal ratios remain controversial, particularly in non-trauma surgical settings. This study aimed to investigate the association between FFP:RBC ratios and 30-day survival in patients undergoing intraoperative MT, with a focus on etiology-specific variations. A retrospective cohort study was conducted at a tertiary care hospital (2017–2022) involving 44 adult surgical patients (≥18 years) with MT, defined as concurrent transfusion of ≥9 units RBC/24 hours and critical administration threshold (CAT) ≥3 units RBC/1 hour. All 44 patients underwent surgeries and met the CAT criteria during perioperative period. Data on demographics, surgical characteristics, fluid balance, blood products, and 30-day mortality were collected. Patients were stratified by FFP:RBC ratio (≤1:2.5 vs. >1:2.5). Statistical analyses included univariate/multivariate Logistic regression and restricted cubic spline modeling to explore nonlinear associations. The 30-day mortality rate was 15.9% (7/44). T test showed that survivors had higher FFP:RBC ratios than non-survivors (median 1:2.1 vs. 1:2.6; P =0.038). The mortality varied by surgical etiology: 0% (obstetric, n=13), 12% (oncologic, n=25), and 66.7% (traumatic, n=6; P =0.003). Multivariable analysis showed that both surgical category ( OR =0.12, 95% CI : 0.03–0.49) and FFP:RBC ratio ( OR =0.25, 95% CI : 0.07–0.91) were independent predictors of the mortality. Patients with FFP:RBC >1:2.5 had significantly lower mortality (6.9% vs. 33.3% in ≤1:2.5; P =0.036). Restricted cubic spline modeling revealed a nonlinear relationship: ratios ≤1:2.5 were associated with exponentially increasing mortality risk, while 1:2.5–1:1.4 (neutral zone) showed minimal impact ( OR ≈1). A trend toward higher survival was observed with FFP:RBC ratios >1:2.5 in intraoperative MT patients, though the small sample size (n=44, 7 deaths) precludes defining a clinical threshold. Mortality varied significantly by etiology, underscoring the need for etiology-tailored transfusion strategies. These exploratory findings highlight the importance of larger, multicenter studies to validate optimal ratios and refine resuscitation guidelines.