Continuous postoperative pericardial flushing reduces postoperative bleeding after coronary artery bypass grafting: a randomized trial by Diephuis, EC, de Borgie, CA, Zwinderman, A, Winkelman, JA, van Boven, W-JP, Henriques, JPS, Eberl, S, Juffermans, NP, Schultz, MJ, Klautz, RJM, Koolbergen, DR