Effect of storage time of transfused plasma on early and late mortality after coronary artery bypass grafting

Objectives: Because some concern has been raised about the storage time of red blood cells and outcomes after cardiac surgery, we investigated whether longer storage time of transfused plasma increases the risk for early or late mortality among patients who have undergone coronary artery bypass grafting. Methods: We retrospectively analyzed the data of all 10,626 patients who underwent isolated coronary artery bypass grafting in Catharina Hospital, Eindhoven, The Netherlands, between January 1998 and December 2007. All patients who received at least 1 unit of plasma intraoperatively or during the first 5 postoperative days were studied. They were divided into 3 groups (only younger plasma, only older plasma, and any older plasma groups) according to the storage time of the plasma (cutoff point, 323 days). Results: After we had excluded 122 patients who were unavailable for follow-up, we found that 375 of the remaining patients (n = 745) received only younger plasma 370 patients received any older plasma, and 200 patients received only older plasma (mean follow-up, 1565 ± 1137 days; median follow-up, 1629 days). The storage time of plasma, when entered as either a continuous variable or a dichotomous variable, was a risk factor for early but not late mortality. Log-rank testing revealed no statistical difference in long-term survival among the groups. Conclusions: Longer storage time of plasma is a risk factor for early but not late mortality among patients who have undergone coronary artery bypass grafting.