Methods: A total of 373 patients (257 males, 116 females; median age 63, range 33 to 85 years) who underwent isolated coronary artery bypass grafting under cardiopulmonary bypass between January 2015 and January 2020 were retrospectively analyzed. The patients who did not develop any postoperative major adverse event were included in Group 1, while those who did constituted Group 2. Preoperative neutrophil-to-lymphocyte ratio, postcardiotomy neutrophil-to-lymphocyte ratio, postoperative Day 1 neutrophil-to-lymphocyte ratio, and neutrophil-to-lymphocyte x platelet ratio were calculated.

Results: Preoperative neutrophil counts, C-reactive protein values, neutrophilto- lymphocyte ratio, total perfusion time, and length of intensive care unit and hospital stay were significantly higher in Group 2 (p=0.019, p=0.028, p<0.001, p=0.027, p<0.001, and p<0.001, respectively). Post-cardiotomy neutrophil, neutrophil-to-lymphocyte ratio, and neutrophil-to-lymphocyte x platelet ratio, along with the postoperative first day white blood cell count, neutrophil, C-reactive protein, neutrophil-to-lymphocyte ratio, and neutrophil-to-lymphocyte x platelet ratio were significantly higher in Group 2 (p=0.004, p<0.001, p<0.001, p=0.019, p=0.003, p=0.001, p<0.001, and p=0.041, respectively). The post-cardiotomy platelet and lymphocyte counts and postoperative first day lymphocyte counts were significantly lower in Group 2 (p<0.001, p=0.007, and p=0.009, respectively).

Conclusion: Post-cardiotomy neutrophil-to-lymphocyte ratio and neutrophilto- lymphocyte x platelet ratio can be easily accessible, inexpensive complete blood count parameters and may be more valuable in predicting major adverse events in patients undergoing coronary artery bypass grafting.