Predicting postoperative ischemic stroke problems in patients following coronary bypass surgery using neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and red blood cell distribution width values

Introduction
Coronary artery bypass grafting (CABG) plays an important role in the revascularization of ischemic heart disease. However, stroke is a rare but extremely serious complication after CABG.

Aim
We investigated the relationship between platelet-lymphocyte ratio (PLR), neutrophil-lymphocyte ratio, red blood cell distribution width (RDW) values, and postoperative ischemic stroke by examining the preoperative complete blood count (CBC) parameters in patients who underwent CABG.

Material and methods
A total of 1240 patients who underwent CABG between September 2016 and June 2019 were included in this retrospective observational study. The diagnosis of ischemic stroke was made in the postoperative period by neurology consultation and radiological imaging. The CBC data used as preoperative values for each case were obtained the day before surgery.

Results
Ischemic stroke was observed in 40 patients. In patients with stroke, the mean age was higher, the hemoglobin (HB) value and lymphocyte count were lower (p < 0.001), and there were also higher neutrophil to lymphocyte ratio (NLR), PLR, and RDW values (p < 0.001), number of mechanical ventilator days, length of stay in the hospital, and length of stay in the ICU (p < 0.001). Statin and acetylsalicylic acid use were statistically significantly higher in patients without ischemic stroke after CABG (p < 0.001); the use of other antiaggregants was found to be higher in stroke patients (p < 0.05). However, age, operation time, PLR, NLR, and RDW values were determined as independent risk factors for ischemic stroke.

Conclusions
In patients undergoing CABG, high preoperative PLR, NLR, and RDW values can be used as useful and independent risk factors for the prediction of postoperative ischemic stroke.