The effect of the Belmont rapid infuser on cold stored whole blood coagulability.

INTRODUCTION: With the large-scale use of whole blood in massive transfusion using rapid infusers/fluid warmers such as the Belmont, questions remain as to whether coagulation potency, platelet number and function are preserved.  We aimed to study functional coagulation capacity and cell counts in whole blood before and after infusion through the Belmont rapid infuser utilizing TEG analysis and complete blood counts. METHODS: We evaluated 10 whole blood units before and after infusion through a Belmont Fluid Management System at a set rate of 200 mL/min and a temperature of 37.4 °C.  Cell counts and thromboelastography function of the specimens were measured. Parameters were compared utilizing paired Student's t-tests and paired Wilcoxon Rank Sign tests. RESULTS: Platelet count, R time, and Maximum amplitude showed significant decreases (defined as p<0.05) after being infused through the Belmont. Hemoglobin, hematocrit, MCV, and alpha angle were not statistically different before and after infusion. CONCLUSION: Infusion of cold stored whole blood in a Belmont infuser, appeared to decrease platelet counts and function as well as activate clotting factors as demonstrated by a shorter R time while not affecting red cell counts or fibrin cross-linking as measured by TEG parameters and cell counts. This suggests that while it is possible to transfuse whole blood through a rapid infuser, platelet quantity and function may be negatively impacted.

Principles, Interpretation, and Evidence-Based Role of Viscoelastic Point-of-Care Coagulation Assays in Cirrhosis and Liver Failure.

Background and Aims: Standard coagulation tests such as prothrombin time, activated partial thromboplastin time, and international normalized ratio are determined by liver-synthesized coagulation factors. Despite an increased international normalized ratio, patients with cirrhosis are in a "rebalanced" state of hemostasis as the concomitant effect of reduced protein C, protein S, and thrombomodulin is not evaluated in standard coagulation tests. The cell-based model of hemostasis indicates additional mechanisms such as systemic inflammation, sepsis, and organ failures tip the delicate coagulation balance to an anticoagulant type in acute-on-chronic liver failure. In acute liver failure, thrombin generation and platelet function remain intact despite a marked prolongation in prothrombin time. We aimed to explain the principles, application, and utility of viscoelastic tests such as thromboelastography, rotational thromboelastometry, and Sonoclot. Methods: We reviewed the available literature from MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trial with the search terms 'coagulation', 'cirrhosis', 'acute-on-chronic liver failure', 'thromboelastography', 'thromboelastometry' and 'sonoclot' for cross sectional studies, cohort studies and randomized trials. Results: The point-of-care viscoelastic tests provide actionable targets for correcting the coagulation defect in a patient with bleeding and provide evidence-based algorithms for use in liver disease. A limitation of these tests is the inability to assess vessel injury and endothelial elements. Conclusion: Global coagulation tests provide a comprehensive estimate of coagulation in vitro; however, their use has only been validated in the setting of liver transplantation. Newer guidelines for hemostatic resuscitation are now accepting these POC tests, but additional data are required to validate their use as standard of care.

Association Between Thrombogenicity Indices and Coronary Microvascular Dysfunction in Patients With Acute Myocardial Infarction.

The association between thrombogenicity and coronary microvascular dysfunction (CMD) has been poorly explored in patients with acute myocardial infarction (AMI). In our real-world clinical practice (N = 116), thrombogenicity was evaluated with thromboelastography and conventional hemostatic measures, and CMD was defined as index of microcirculatory resistance of >40 U using the invasive physiologic test. High platelet-fibrin clot strength (P-FCS) (≥68 mm) significantly increased the risk of postprocedural CMD (odds ratio: 4.35; 95% CI: 1.74-10.89). Patients with both CMD and high P-FCS had a higher rate of ischemic events compared to non-CMD subjects with low P-FCS (odds ratio: 5.58; 95% CI: 1.31-23.68). This study showed a close association between heightened thrombogenicity and CMD and their prognostic implications after reperfusion in acute myocardial infarction patients.

Perioperative monitoring in liver transplant patients.

Liver transplant (LT) is a major surgical undertaking involving major fluid shifts, hemodynamic instability and metabolic derangements in a patient with preexisting liver failure and multisystemic derangements. Monitoring and organ support initiated in the preoperative phase is continued intraoperatively and into the postoperative phase to ensure an optimal outcome. As cardiovascular events are the leading cause of non-graft related death among LT recipients, major emphasis is placed on cardiovascular monitoring. The other essential monitoring are the continuous assessment of coagulapathy, extent of metabolic derangements, dyselectrolytemis and intracranial pressure monitoring in patients with fulminant hepatic failure. The type and extent of monitoring differs with need according to preexisting child status of the patient and the extent of systemic derangements. It also varies among transplant centers and is mainly determined by individual or institutional practices.