Platelets
-
Randomized Controlled Trial
Cross validation of aspirin effect in healthy individuals by Impact-R and PFA-100: a double blind randomized placebo controlled trial.
The main objective of this study was to compare testing for aspirin response in healthy volunteers by two high shear methods in a randomized double blind placebo controlled study. Seventeen healthy male individuals were randomized for aspirin 160 mg per day for 7-10 days, and 20 age matched controls for placebo for the same period. At study entry and 7-10 days thereafter we determined high shear-induced platelet adhesion to polystyrene after pre-incubation with arachidonic acid using the Cone and Plate(let) analyzer (Impact-R), and the closure time of collagen/epinephrine cartridges obtained by the PFA-100 (CEPI-CT). ⋯ The response to aspirin varied considerably among healthy individuals, but both methods were suitable to demonstrate the aspirin effect. There was, however, a significant level of absent concordance between the tests. Since the trial design cannot provide data on the specificity of the different tests, only clinical experience can determine their usefulness.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Effects of preemptive therapy with milrinone or amrinone on perioperative platelet function and haemostasis in patients undergoing coronary bypass grafting.
Preemptive therapy with a phosphodiesterase III inhibitor preserves cardiac function and oxygen transport after cardiac surgery, and its safety on platelet function and haemostasis must be verified. We examined the effects of preemptively administered milrinone or amrinone on platelet function and haemostasis. In 45 cardiac surgery patients, we randomly administered milrinone 50 microg/kg plus 0.5 microg/kg/min for 10 hours, amrinone 1.5 mg/kg plus 10 microg/kg/min infusion for 10 hours, or placebo at release of aortic cross-clamp. ⋯ The mean platelet counts 3 days postoperative in the milrinone and amrinone groups did not significantly differ from the placebo group (10.9 +/- 3.3 and 12.1 +/- 3.8, vs. 12.1 +/- 3.4x10(4) per cubic millimeter, respectively), and chest-tube drainage in the first 24 hours did not significantly differ (450 +/- 156 and 391 +/- 184, vs. 448 +/- 140 ml, respectively). Although there were changes in platelet aggregation consequent to surgery there was no significant differences in platelet aggregation or other haematological values among the three groups. Preemptive therapy of milrinone or amrinone does not deteriorate perioperative platelet function and haemostasis beyond surgical interventions.