PFA-100 closure times after stimulation with CT-EPI. Shown are PFA-100 closure times after stimulation with closure time– epinephrine (CT-EPI) measured in thrombocytopenic CB (gray bars) and adult PB (black bars) samples transfused in vitro with neonatal (CB) or adult (PB) platelets (Plt). CB samples generated shorter CT-EPI times than PB samples. Within each whole-blood source, transfusion with adult platelets resulted in significantly shorter CT-EPI times compared with neonatal platelets. Thrombocytopenic CB samples mixed with adult platelets generated the shortest CT-EPI times.*P < .05. Used with permission from Ferrer-Marin et al.⁴³