Does rotational thromboelastometry accurately predict coagulation status in patients with lupus anticoagulant?

INTRODUCTION: Rotational thromboelastometry (ROTEM) is increasingly used as a tool for monitoring coagulation status. However, ROTEM is susceptible to misinterpretation due to particular coagulation abnormalities. Here, we report the effects of lupus anticoagulant (LA) on ROTEM. METHODS: A prospective observational analysis was performed on 16 children with prior studies indicating the presence of LA or antiphospholipid antibodies. ROTEM analysis was performed, and samples were further analyzed by adding phospholipids (PL) to repeat ROTEM analysis if clotting time (CT) abnormalities were discovered with comparison to ROTEM using an equal volume of isotonic saline. Prothrombin time (PT), activated partial thromboplastin time (APTT), dilute Russell's viper venom test (DRVVT), hexagonal phase phospholipid neutralization test (StaClot LA), and factor II activity studies were additionally performed. RESULTS: Eighteen samples were analyzed by ROTEM. Prolonged CT on INTEM and EXTEM was observed for 11 samples. Samples with CT prolongation had high DRVVT ratios and prolonged APTT. Further, the addition of PL partially reversed this effect, demonstrating PL-dependent inhibition as the cause of CT prolongation. No factor II deficiencies were identified, excluding LA hypoprothrombinemia syndrome as a cause of these findings. CONCLUSION: Strongly positive LA can prolong the CT on ROTEM studies and lead to erroneous conclusions regarding coagulation status in this patient population.

Irradiation and prolonged storage of red cells are associated with increased adverse events.

BACKGROUND: Red blood cell (RBC) transfusion is associated with the most transfusion-related adverse events (AE). Recent clinical studies showed no significant difference in transfusion-associated mortality between fresh and older RBCs. However, the impact of storage duration as well as irradiation on nonfatal yet much more common complications has not been fully investigated. MATERIALS/METHODS: In this retrospective study of RBC transfusion-associated AEs, a total of 188,562 units of leucocyte-reduced RBCs were transfused in approximately 5·5 years. After excluding washed, deglycerolized, autologous or directed RBCs and RBCs transfused during a massive transfusion protocol, 149,052 units were analysed. Attributes of RBCs including storage time, collection method, CMV serological status and gamma irradiation, as well as the recipient's gender, were analysed. A total of 358 RBC transfusion AEs were categorized into allergic and non-allergic reactions and analysed. RESULTS: Univariate and multivariate logistic analyses showed that irradiated RBCs were associated with a significantly increased frequency of non-allergic reactions (OR (95% CI): 1·89 (1·52, 2·35); P < 0·001). There was a significant association between the frequency of non-allergic reactions and the storage time of irradiated RBCs (OR (95% CI): 1·024 (1·001, 1·048); P = 0·042). In contrast, there was no association between the frequency of allergic reactions and the storage time of irradiated RBCs or between the age of non-irradiated RBCs and the frequency of non-allergic reactions. CONCLUSIONS: Prolonged storage of irradiated RBCs was associated with a significant increase in non-allergic transfusion reactions. Overall, the irradiated RBCs appeared to cause more non-allergic reactions compared with non-irradiated RBCs.

Prolonged platelet storage associated with increased frequency of transfusion-related adverse events.

BACKGROUND: Platelets (PLTs) have been associated with the highest rate of transfusion-associated adverse events (AEs) among all blood products. Most of PLT-associated AEs are considered to have an inflammatory mechanism. However, it is still unclear whether prolonged storage of platelets is associated with an increased rate of transfusion-related AEs, especially in the era of universal prestorage leucoreduction. METHODS/MATERIALS: In this retrospective study, 52 649 PLT products consisting of about 80% apheresis PLTs and 20% whole blood-derived (WBD) PLTs were transfused to 9415 patients from July 2011 to March 2017. All the PLTs were leucoreduced prior to storage. All but 69 units of the apheresis PLTs were irradiated and none of WBD PLTs were irradiated. During this period, a total of 284 AEs that were reported to the transfusion service were analysed. RESULTS: Univariate and multivariate logistic analyses showed that apheresis/irradiated PLTs and PLT age were associated with a significantly increased frequency of inflammation type AEs (OR (95% CI): 2·24 (1·32, 4·15) and 1·30 (1·12, 1·52), respectively). There was a significant increase in the frequency of inflammation AEs associated with prolonged storage of apheresis/irradiated PLTs [OR (95% CI): 1·26 (1·03, 1·53)]. In contrast, there was no association between allergic symptoms and PLT age. Moreover, the frequency of transfusion AEs associated with apheresis/irradiated PLTs (57·2/10 000) was significantly higher than that of WBD/nonirradiated PLTs (26·0/10 000) (P < 0·01). CONCLUSION: Prolonged storage of apheresis/irradiated PLTs was associated with a higher frequency of inflammation AEs. Apheresis/irradiated PLTs caused more AEs than WBD/nonirradiated PLTs.