Nuttall, Gregory A.

Background: Transfusion has a persistent low risk of transfusion-transmitted infection and transfusion-associated graft- versus -host disease that may be addressed using pathogen reduction. The Red Cell Pathogen Inactivation (ReCePI) trial tested whether amustaline/glutathione pathogen-reduced red cells are noninferior to conventional transfusions for support of acute surgical blood loss. Methods: A phase 3, double-blinded, noninferiority trial randomized cardiac or thoracic–aorta surgery patients with increased risk of red cell transfusion to receive pathogen-reduced or conventional red cells during and for 7 days postsurgery. The primary endpoint was the proportion of patients with acute kidney injury (AKI), which is defined as an increase from baseline of greater than or equal to 0.3 mg/dl serum creatinine within 48 h of surgery. Noninferiority was claimed if the upper bound 95% CI of the treatment difference was less than half (50%) of the observed conventional arm incidence. Adverse events and treatment-emergent red cell antibodies were assessed for 28 and 75 days, respectively. Results: A total of 581 subjects were randomized, and 321 (55%) were transfused with study red cells. Transfused subjects in both arms had similar baseline demographics, medical histories, hemoglobin levels, and surgical procedures. Hemoglobin day 3 nadir levels (8.6 g/dl [7.8 to 9.2] in the pathogen-reduced arm; 8.4 g/dl [7.8 to 9.3] in the conventional arm; P = 0.52) were comparable. Incidence of AKI by 48 h was 46 of 157 (29.3%) in the pathogen-reduced arm and 45 of 161 (28.0%) in the conventional arm (treatment difference, 0.7%; 95% CI, −8.9 to 10.4%; noninferiority margin, 14.0%; P = 0.001 for noninferiority). AKI within 7 days by Kidney Disease Improving Global Outcomes staging criteria was not different (59 of 159 [37.1%] in the pathogen-reduced arm; 55 of 162 [34.0%] in the conventional arm; P = 0.53), but stage III was more common in the pathogen-reduced arm (pathogen-reduced arm, 15 of 159 [9.4%]; conventional arm, 7 of 162 [4.3%]; P = 0.075). Of 159 pathogen-reduced red cell recipients, 5 (3.1%) developed specific, low-titer antibodies without evidence of hemolysis. Conclusions: The incidence of AKI in recipients of pathogen-reduced red cells was noninferior to conventional red cell transfusion. Treatment-emergent antibodies were uncommon and not clinically significant.

AbstractBackgroundThe clinical significance of natural and treatment‐emergent antibodies specific for amustaline/glutathione pathogen‐reduced red blood cells (PRRBCs) is not known.Study Design and MethodsA Phase 3, randomized clinical trial of PRRBCs (ReCePI) compared PRRBCs with conventional RBCs in cardiac or thoracic‐aorta surgery. Subjects transfused during and for 7 days after surgery were screened for PRRBC‐specific antibodies at baseline, 28 and 75 days post‐surgery. Subjects with treatment‐emergent antibodies were assessed for evidence of hemolysis. Cryopreserved subject RBC samples were assayed by flow cytometry for circulating PRRBCs using an acridine‐specific (2S197‐2M1) monoclonal antibody, and for human IgG‐coated RBCs. RBC‐surface acridine density was quantitated using a commercial calibrated phycoerythrin (PE)‐bead panel.ResultsFive of 159 (3.1%) PRRBC and zero of 162 conventional RBC recipients developed treatment‐emergent PRRBC‐specific IgG, low titer antibodies detected 26–80 days post‐surgery after exposure to 1–3 PRRBC units, without clinical evidence of hemolysis. DAT and eluate were weak (w+) positive and PRRBC‐specific in one subject. A monocyte monolayer assay (MMA) was non‐reactive in the three subjects with an interpretable result. Flow cytometry demonstrated circulating PRRBCs in all five subjects expressing surface acridine concentrations at the limit of detection (approximately 150–301 PE molecules/RBC) compared with freshly transfused PRRBCs (approximately 7500 PE molecules/RBC). In some samples, loss of surface acridine expression could not be distinguished from clearance of the PRRBCs.DiscussionTreatment‐emergent PRRBC‐specific antibodies with the characteristics of nonclinically significant antibodies were detected in five subjects transfused with PRRBCs. Flow cytometry demonstrated persistent circulating PRRBCs with minimal surface acridine expression. (www.ClinicalTrials.gov Identifier NCT03459287).

Introduction: Red blood cell (RBC) transfusion is a lifesaving intervention with a low but persistent risk of transfusion-transmitted infection. Amustaline/glutathione RBC pathogen-reduction (PR) technology is designed to proactively inactivate a broad spectrum of viruses, bacteria, protozoa and leukocytes by chemically crosslinking nucleic acids and preventing replication and transcription. The Red Cell Pathogen Inactivation (ReCePI) trial was a Phase III, double-blinded, randomized non-inferiority study comparing PR and conventional RBCs for the support of acute anemia. Methods/Study Design: Complex cardiac or thoracic-aorta surgery patients received conventional (Control) or PR RBCs (Test) during and for 7 days after surgery. The protocol was conducted with ethics committee approval at all participating centers and written informed consent from all participants. Hemoglobin levels, blood utilization and serum creatinine were assessed as indicators of efficacy and oxygenation of tissues (Karkouti et al. Br J Anaesth. 2012; 109 Suppl 1: i29-i38). The primary endpoint was the incidence of acute kidney injury (AKI) measured as change in serum creatinine from baseline within 48 hours of surgery, a predictor of adverse postoperative outcomes including mortality by Day 30 post-surgery (Lassnig et al. Am Soc Nephrol 2004; 1597-1605). Secondary endpoints included AKI occurring up to 7 days post-surgery (KDIGO Clinical Practice Guideline for AKI, Kidney Inter, Suppl. 2012;2:1-138); death or the need for renal replacement therapy by 30 days post-surgery; PR RBC-specific antibodies; and death by day 75 post-surgery. With >292 subjects enrolled, the study had 80% power to demonstrate non-inferiority, assuming an AKI incidence of 30% with conventional RBCs and a non-inferiority margin of half the conventional RBC rate. Under these circumstances, an absolute treatment increase of 5% in the AKI rate in the PR RBC arm would fail the non-inferiority test. This work was supported by a contract with the US Biomedical Advanced Research and Development Authority (HHS010020160009c) with Cerus Corporation. Results: Five-hundred and eighty-one subjects were randomized and 321 (55%) transfused in 18 US hospitals. In the modified intent-to-treat analysis subjects receiving Test and Control RBCs had similar median [IQR] total blood loss (1500 [940-2475] mL Test, 1733 [1060-2880] mL Control, p=0.310) and comparable median hemoglobin levels at baseline and immediately post-surgery (9.8 [8.9-10.9] g/dL Test, 9.6 [8.6-10.6] g/dL Control, p=0.157) and for 7 days after surgery, The PR RBC arm was transfused with fewer RBCs, measured as total RBC Hb transfused over 7-days (169.0 [102.0-240.0] g Hb PR arm, 188.0 [126.0-295.0] g Hb, conventional RBC arm, p=0.008). The incidence of AKI was 29.3% (46/157) for Test and 28.0% (45/161) for Control. The treatment difference was 0.74% (95% CI -8.9, 10.4%, non-inferiority margin 14.0%, p=0.001 for non-inferiority). Non-inferiority was also achieved by the per protocol analysis. Average mean change in serum creatinine within 48 hours of surgery was comparable (Test 0.020, Control 0.23 mg/dL, P=0.515). Adverse events, serious adverse events and deaths on study were not different. Five of 159 (3.1%) PR RBC recipients developed low titer PR RBC-specific antibodies without clinical signs of hemolysis. Flow cytometry analysis revealed persistent circulating PR RBCs with uniform antigen loss (modulation). Low level human IgG antibody binding was demonstrated in 3 of 5 subjects. Conclusions: PR RBCs showed equivalent hemoglobin support for acute bleeding patients undergoing cardiac or thoracic-aorta surgery while using less transfused total RBC Hb over 7 days. The incidence of AKI in patients transfused with PR RBCs was non-inferior to that observed with conventional RBCs, indicative of effective tissue oxygenation. Treatment-related antibodies to PR-RBC were observed only in Test subjects, the antibodies were low titer, transient, without clinical hemolysis, and persistent circulating PR RBCs were detected with modulated low level acridine antigen expression (www.clinicaltrials.gov #NCT03459287).

Introduction: Post-Cardiopulmonary Bypass (CPB) coagulopathy results in bleeding, transfusion and re-exploration, and increases morbidity, mortality and cost. Some studies have reported a relationship between individual factor levels and chest tube drainage as a marker of bleeding, but few have reported that relationship for multiple factors. Methods: With IRB approval and informed consent, 98 patients, ages 18 - 85, undergoing cardiac surgery with cardiopulmonary bypass (CPB) were studied. Factor levels measured five minutes post-protamine included fibrinogen (FIB), and factors II, V, VII, VIII, Von Willebrand Factor Antigen (VWF Ag), Ristocetin Cofactor (VWF Activity), IX, X, XI and XIII. Linear regression models examined the relationship between factor levels and post-op chest tube drainage over 24 hours as a surrogate marker for bleeding. An effect size (ES) was calculated so that each factor deficiency multiplied by the ES and the patient's weight in kg would estimate the contribution of that factor to bleeding. Factors were ranked from most to least impact on bleeding. Conversely, said ES would estimate the decrease in bleeding achieved by a percentage increase in a deficient factor level if such factor was known to be deficient. Results: F:II was 1st (most associated with bleeding), ES = -0.137, 95% CI -0.214 - -0.059, p < 0.001; F:X was 2nd, ES = -0.130, 95% CI -0.202 - -0.058, p < 0.001; F:VII ES = -0.121, 95% CI -0.198 - -0.045, p = 0.002; F:XI ES = -0.109, 95% CI -0.16 - -0.058, p < 0.001; F:IX ES = -0.100; 95% CI -0.135 - -0.065, p < 0.001; F:V ES = - 0.065; 95% CI -0.114 - -0.016, p = 0.011; F:XIII ES = - 0.055; 95% CI -0.099 - -0.011, p = 0.016; FIB ES = - 0.042; 95% CI -0.063 - -0.022, p < 0.001; F:VIII ES = - 0.007; 95% CI -0.020 - 0.006, p = 0.318; VWF Ag ES = 0.002; 95% CI -0.016 - 0.019, p = 0.855; VWF Activity ES = 0.004; 95% CI -0.015 - 0.023, p = 0.671. Conclusions: Factors VIII, VWF Ag and Ristocetin Cofactor demonstrated no relationship with bleeding, perhaps because they are elevated as acute-phase reactants. In theory, raising F:II level post-CPB by 30% in an 80 kg patient might decrease bleeding by 328 ml, and raising F:X level post-CPB by 30% in an 80 kg patient might decrease bleeding by 312 ml, etc. A weakness of this study is that the sample size was too small to perform a multi-variate analysis considering all factor levels. Still, the data suggest four-factor prothrombin complex concentrate (PCC) might be a more effective treatment for post-CPB coagulopathy than FFP. The data do not confirm cause and effect; that would require a large study with control and treatment arms. If multiple factor levels could be measured in a rapid and cost-effective manner it might aid in targeted treatment of post-CPB coagulopathy. The data suggest that work should be performed to better elucidate the contribution of coagulation factor deficiencies to post-CPB bleeding, as improved treatment of such factor deficiencies might decrease bleeding and transfusion requirements.

AbstractBackgroundRecently the US Food and Drug Administration has granted variances to select blood centers to supply cold‐stored platelet components (CSP). In hemorrhage resuscitation warming of blood components with approved fluid warming devices is common.Study Design and MethodsPathogen‐reduced apheresis platelet units were collected and stored in one of two ways: (1) CSP‐I, (2) CSP‐D. CSP‐I were collected and immediately stored at 1–6°C until used. CSP‐D were collected and stored at 20–24°C for 5 days and transferred to storage at 1–6°C until use. Aggregometry using arachidonic acid (AA), adenosine diphosphate (ADP) and collagen as agonists was performed on the unit samples before and after the units were infused through a Ranger blood‐warming device.ResultsCSP‐I, 23 units, had very high aggregation responses to all agonists (all ≥47.6 ± 20.7). There was a statistically significant reduction in ADP‐induced aggregometry results from 55.1 ± 23.2 before compared to 33.5 ± 14.6 following infusion of the PLT through the blood warmer (p < .001). There were no differences in AA and collagen aggregometry results before and after the infusion of the platelets through the blood warmer. CSP‐D had 5 of the 15 units with visible clotting in the bag. The 10 CSP‐Ds studied had lower aggregation than all agonists before and after infusion through the blood‐warming device (all ≤49.9 ± 35.9).ConclusionWe detected a statistically significant reduction in ADP‐induced aggregometry in CSP‐I run through a Ranger blood‐warming device with no change with AA or collagen agonist aggregometry.

Background: The safety of triple antiemetic therapy consisting of ondansetron, haloperidol, and a steroid, to surgical patients is unknown. Objective: To determine the incidence of torsade de pointes (TdP) or death following perioperative administration of triple antiemetic therapy. Methods: A retrospective cohort study identified 19,874 patients who received 22,202 doses of triple antiemetics during the 2.5-year time frame from March 4, 2020 to September 7, 2022 for surgical nausea prophylaxis or treatment of nausea. These patients above were cross-matched with an electrocardiogram and adverse outcome database; this identified 226 patients with documentation of a QTc > 450 ms, all ventricular tachycardias including TdP within 48 hours of receiving triple antiemetic therapy, or death within 7 days of receiving ondansetron. Results: There were 3 patients who had documented VT (n = 3), but there were no documented incidents of TdP (n = 0). There were 9 codes called on patients within 48 hours of medication administration, and none of them were due to ventricular arrythmias (n = 0). A total of 11 patients died within 7 days of triple antiemetic therapy. Ten of the 11 deaths were determined to not be from the triple antiemetic. One patient died at home within 24 hours of the procedure of an unknown cause (n = 1). Conclusions and Relevance: No episodes of TdP were identified in patients receiving triple antiemetic therapy perioperatively, though the cause of death in 1 patient could not be determined. This suggest that low-dose triple antiemetic therapy is low risk for the development of TdP.

Abstract Background Red blood cell (RBC) transfusion is a critical supportive therapy in cardiovascular surgery (CVS). Donor selection and testing have reduced the risk of transfusion-transmitted infections; however, risks remain from bacteria, emerging viruses, pathogens for which testing is not performed and from residual donor leukocytes. Amustaline (S-303)/glutathione (GSH) treatment pathogen reduction technology is designed to inactivate a broad spectrum of infectious agents and leucocytes in RBC concentrates. The ReCePI study is a Phase 3 clinical trial designed to evaluate the efficacy and safety of pathogen reduced RBCs transfused for acute anemia in CVS compared to conventional RBCs, and to assess the clinical significance of treatment-emergent RBC antibodies. Methods ReCePI is a prospective, multicenter, randomized, double-blinded, active-controlled, paralleldesign, non-inferiority study. Eligible subjects will be randomized up to 7 days before surgery to receive either leukoreduced Test (pathogen reduced) or Control (conventional) RBCs from surgery up to Day 7 post-surgery. The primary efficacy endpoint is the proportion of patients transfused with at least one study transfusion with an acute kidney injury (AKI) diagnosis defined as any increased serum creatinine (sCr) level ≥0.3 mg/dL (or 26.5 µmol/L) from presurgery baseline within 48±4 hours of the end of surgery. The primary safety endpoints are the proportion of patients with any treatment-emergent adverse events (TEAEs) related to study RBC transfusion through 28 days, and the proportion of patients with treatment-emergent antibodies with confirmed specificity to pathogen reduced RBCs through 75 days after the last study transfusion. With ≥292 evaluable, transfused patients (>146 per arm), the study has 80% power to demonstrate non-inferiority, defined as a Test group AKI incidence increase of no more than 50% of the Control group rate, assuming a Control incidence of 30%. Discussion RBCs are transfused to prevent tissue hypoxia caused by surgery-induced bleeding and anemia. AKI is a sensitive indicator of renal hypoxia and a novel endpoint for assessing RBC efficacy. The ReCePI study is intended to demonstrate the non-inferiority of pathogen reduced RBCs to conventional RBCs in the support of renal tissue oxygenation due to acute anemia and to characterize the incidence of treatment-related antibodies to RBC.

AbstractStudy ObjectiveThe primary objective of this retrospective safety study was to determine the incidence of torsades de pointes (TdP) or death following perioperative administration of low‐dose, 4 mg, ondansetron for postoperative nausea and vomiting.Design and SettingThis is a single‐center retrospective clinical trial.PatientsThe authors identified 32,737 patients who received 37,589 doses of ondansetron during a 2‐year time frame between March 2009 and February 2011 for surgical nausea prophylaxis or treatment of nausea.Measurements and Main ResultsPatients were cross‐matched with an electrocardiogram and adverse outcome database; this identified 4759 patients with documentation of a QTc >450 milliseconds (ms), all ventricular tachycardias including TdP within 48 hours of receiving ondansetron, or death within 7 days of receiving ondansetron. No patients developed TdP or died as a direct result of ondansetron administration (n = 0; event rate = 0.0 per 10,000, 95% CI 0.0 to 1.1 per 10,000). Forty‐six of 32,737 surgical patients had documented monomorphic ventricular tachycardia (VT) (n = 14; event rate = 4.3 per 10,000, 95% CI 2.3 to 7.2 per 10,000) or died (n = 32; event rate = 9.8 per 10,000, 95% CI 6.7 to 13.8 per 10,000) within 48 h of ondansetron administration. All monomorphic VT episodes were precipitated by existing cardiovascular disease; and 7 of 14 patients had documented monomorphic VT prior to receiving ondansetron. Of the 32 surgical patients who died, all deaths were precipitated by pre‐existing disease.ConclusionNo episodes of TdP were identified in patients receiving ondansetron perioperatively. This suggests that low‐dose ondansetron does not contribute to the development of TdP.