The Optimal Time Of Cryopreserved Umbilical Cord Blood Infusion

Objective Investigate the infusion-related adverse events of cryopreserved cord bloodand analyze cause of the major adverse event. Explore the effect of preservation time invitro on cord blood hematopoietic stem cell activity, in order to provide a optimalinfusion time of cryopreserved cord blood, for a theoretical basis to decrease theincidence of adverse events.Methods Part1: Investigate116patients with hematologic malignancies andnon-malignant diseases, who underwent unrelated cord blood transplantion from atransplant center in Anhui from January2000to December2011. Demographicvariables collect questionnaire was used to investigate the characteristics of patients andcord blood products, the infusion-related side effects were evaluated in the infusionand the cause of the major adverse event was analyzed. Part2:30cord blood units,which were cryopreserved at–196℃for1-10years, cell viability, early apoptosis ofCD34+CD45dim/-cells and the recovery of colony-forming cell (CFC) were determinedwithin30minutes post-thaw(PT). The speed of platelet and neutrophil engraftment ofthe30patients were monitored.Results Part1: In116cases of cord blood transplant patients, a total of96patients(82.8%) experienced adverse events related to infusion of cord blood units.The incidence of hypertension was67.2%(78cases), in which26patients had grade1 (33.3%) hypertension,22cases (28.2%) in grade2hypertension,28cases (35.9%) ingrade3hypertension and2patients (2.6%) with grade4hypertension. In the closemonitoring and care, all the116patients were successfully completed the infusion, nopatients experienced life-threatening side effects or needed discontinuation of cordblood unit infusion. Univariate analysis indicated that shorter infusion time and highernucleated cells infused to patients per minute were found to be higher incidence ofhypertension (P=0.000,P=0.023). Part2: Within30minutes, the viability decreasedwith time(P <0.01), early apoptosis of CD34+CD45dim/-cells was better preserved overtime. Although at time point PT30, the recovery of CFC decreased compared to PT0(P <0.05), the CFC assays were better preserved within20minutes. All the30CBcells engrafted well in patients.Conclusion Part1: The infusion-related adverse events of cryopreserved cord bloodwere frequently observed, especially the incidence of hypertension is high. The infusiontime and nucleated cells infused to patients per minute are factors contribute tohypertension. Part2: To preserve20minutes in vitro does not affect the activity of cordblood hematopoietic stem cells, thus, the optimal infusion time of cryopreserved cordblood may be20minutes.