View clinical trials related to Platelet Dysfunction.
Filter by:This study aims to determine whether cold-stored platelets (CSP) are equally, more effective, or uniquely effective at reversing the effect of dual antiplatelet therapy in healthy human subjects compared to room-temperature-stored platelets (RTP). The investigators plan to enroll healthy human subjects without risk factors for bleeding to achieve 60 complete data sets. Each subject will donate two apheresis platelet units. One platelet unit will be stored in the cold (CSP) and one platelet unit will be stored at room temperature (RTP). Subjects will be given dual anti-platelet therapy (aspirin and clopidogrel) prior to autologous transfusion of each unit. Platelet function testing will be performed before and after transfusion to measure reversal of the antiplatelet drugs.
Patients with severe subarachnoid hemorrhage (SAH) may present platelet and coagulation dysfunctions immediately after the stroke on admission at the hospital, and persisting up to 3-4 weeks after the onset. This study aimed to investigate the platelet function as assessed by impedance agregometry (ROTEM Platelet) and platelet adhesion (PFA), and the coagulation profile as assessed by ROTEM, over three evolutive times.
The aim of this study was to determine the prevalence of clopidogrel resistance among a selected group of patients undergoing elective percutaneous coronary intervention and to observe whether there was any south-Asian (Indo-Trinidadian) predilection for HPR considering the well-established epidemiologic trends for accelerated CAD within this subgroup.
Disorders of platelet function are characterized by variable mucocutaneous bleeding manifestations and excessive hemorrhage following surgical procedures or trauma. Generally, most patients have mild to moderate bleeding manifestations with a prolonged bleeding time. Platelet aggregation and secretion studies using platelet-rich plasma (PRP) provide evidence for platelet dysfunction but are neither predictive of severity of clinical manifestations nor the molecular mechanisms. Glanzmann's thrombasthenia (GT) is a rare autosomal recessive genetic bleeding syndrome characterized by defects in platelet aggregometry. The clinical phenotype of patients with GT is variable. Some suffer from severe bleeding, while others have only mild bleeding. Some studies found bleeding severity in GT was influenced by the abundance and functioning of platelet receptors involved in aggregation and adhesion. In addition to a complete medical history, a GT diagnosis requires a comprehensive laboratory workup, including platelet aggregation analysis, and a confirmation by flowcytometry or western blotting with monoclonal antibodies that recognize the GPIIb/IIIa complex. Platelet flow cytometry is an emerging tool in diagnostic and therapeutic hematology. It is eminently suited to study the expression of platelet surface receptors both qualitatively as well as quantitatively. Aim of the study:- - Determine the role of flowcytometry as a quantitative measurement tool of platelets surface glycoproteins in patients with inherited thrombocytopathies and its correlation with bleeding severity of these patients. - To compare the efficacy, advantages and disadvantages between platelets flowcytometry and aggregometer in diagnosing various inherited thrombocytopathies.
This study will measure primary hemostatic ability using the T-TAS 01 System with PL chip, with a comparison to clinical truth.
This study evaluates coronary artery disease after heart transplantation and its relation to platelet function. Furthermore, we will evaluate extracorporeal photopheresis as treatment of coronary artery disease after heart transplantation.
In this study, the investigators are going to investigate the effects of remote ischemic preconditioning on platelet activation in patients undergoing cardiac surgery with cardiopulmonary bypass.
Open heart surgery requires the use of a cardiopulmonary bypass (CPB) circuit. As blood flows across the artificial surfaces of the CPB circuit, platelets are activated and consumed. This activation results in a profound inflammatory reaction and need for transfusion. This reaction is intensified in younger, smaller patients undergoing longer, more complex open heart surgery. Nitric oxide is naturally released by vascular endothelial surfaces and acts as a signaling molecule which prevents platelet activation. The investigators hypothesize that the addition of the nitric oxide to the sweep gas of the oxygenator during cardiopulmonary bypass surgery will replace this natural endothelial function and thus prevent platelet activation and consumption. The investigators plan to test this hypothesis with a pilot double blinded, randomized trial of 40 patients less than a year of age undergoing cardiac surgery requiring CPB.
This study builds, in part, upon preliminary results generated as part of the Pharmacogenomics Anti-Platelet Intervention (PAPI) Study (NCT00799396). The purpose of this investigation is to assess the impact of genetic variation in the carboxylesterase 1 (CES1) on response to clopidogrel as well as dual antiplatelet therapy (i.e. clopidogrel and aspirin), as assessed by ex vivo platelet aggregometry, in healthy Amish individuals. The investigators hypothesize that participants who carry alleles that modify the activity or expression of CES1 will have altered response to clopidogrel as well as dual antiplatelet therapy.
This study evaluates the impact of platelet transfusion on geriatric patients with platelet dysfunction from Traumatic Brain Injury. The authors hypothesize that patients will recover better if their platelet dysfunction is corrected with platelet transfusion.