(P-CB-6) Bleed Time and Beyond: An Assessment of Donor Factors Contributing to Fibrin Clots

Background/Case Studies: Fibrin Clots cause filter failures in the manufacturing of Leukocyte-Reduced Red Blood Cells (LRBC) or Whole Blood (WB). The factors contributing to the cause of fibrin clots is not fully understood. Duration of the blood donation (bleed time) and insufficient mixing during collection have been attributed to increased clotting. Other factors such as ABO group and gender have not been assessed. This study was performed to assess additional donor factors including bleed time.

Study

Design/Methods: ABO group, gender, product type, product discard reason code and bleed times for LRBC and WB donated for January 2023-December 2024 (n=505) were collected from the BECS (WellSky). Bleed time data was grouped into categories with a maximum of >23 minutes. LRBCs and WB discarded for reason code "Fibrin Clots" were compared to an unaffected comparison group consisting of red blood cell products made into successful leukocyte-reduced products collected from January 2023-December 2024 (n=3287). The incidence of fibrin clots was compared between gender, ABO groups, and bleed time variables. Statistical methods included Chi-square (X2) testing and logistic regression modeling.

Results/Findings: Consistent with the literature, there was a statistically significant difference in fibrin clots especially for those with bleed times categories ≥16 minutes compared to those ≤7 minutes (p < .001). (Table 1) In addition, there was a statistically significant difference in fibrin clot occurrence when comparing males versus females (p < .001) and when comparing ABO groups (p=.001). After adjusting for ABO group and bleed time, males had 3.37 times higher odds and a Confidence Interval (CI) [2.57-4.16] compared to females, demonstrating males in this sample were at >3 times higher risk of having RBC products discarded due to fibrin clots.

Conclusions: Duration of the blood donation bleed time impacts the risk of discarding RBC products due to fibrin clots, particularly when it is >16 minutes. ABO groups appear to have some impact. Males have a higher risk of fibrin clots compared to females after adjusting for ABO group and bleed time. Bleed time alone does not appear to be the only contributing factor to filter failures in the blood manufacturing process.