10-years analysis of cryobag fracture in a large inventory of cellular therapy products: rates and risk factors.

Cryobags play a critical role in freezing, storing, and transporting cellular therapy products but are prone to fractures, which can disrupt patient outcomes and facility workflows. This study evaluated the incidence, risk factors, and impact of cryobag fractures in a large inventory of cellular therapy products in Brazil. A retrospective cohort study included 4514 cryobags from 2262 peripheral blood stem cell collections processed between 2015 and 2024 at a single center supporting nine transplant facilities. Cryobags were frozen at - 80 °C and stored in nitrogen tanks. Fractures and leaks were identified through routine visual inspections. Among the cryobags, 15 (0.3%) fractured, with 12 detected at processing facility and 3 after release. The fracture rate was 0.37 per 100 bag-years, with a cumulative incidence of 1% at 3.62 years. Of these, 8 were discarded, and 7 were salvaged and infused into six patients. Two salvaged cryobags underwent bedside recovery, while five were recovered aseptically in the processing facility. Positive bacterial cultures were commonly found in salvaged products. In multivariate analysis, a higher total nucleated cell count per cryobag remained an independent risk factor for fracture (OR = 1.005; 95% CI: 1.0002-1.0099; p = 0.046). Following implementation of quality improvement initiatives based on root cause analysis, no further fractures were observed. These findings highlight the importance of monitoring cell concentration and adjusting cryopreservation protocols to mitigate risks. Adding overwraps may provide additional protection for cryobags at higher risk, reducing the likelihood of microbial contamination and improving the safety and reliability of cellular therapy products.