The effect of spinal anesthetic technique on neutrophil to lymphocyte ratio and postoperative mortality in elderly patients with coronary artery disease undergoing hip replacement surgery

Abstract

Introduction: This study aimed to determine the effect of anesthetic techniques on the neutrophil-to-lymphocyte ratio in elderly patients with coronary artery disease who underwent hip replacement surgery. Materials and Method: In this retrospective cohort study, we reviewed the medical records of 41 elderly patients with coronary artery disease who underwent hip replacement surgery between January 2015 and September 2017. The following data were collected: Demographic characteristics; neutrophil-to-lymphocyte ratio measured preoperatively (T0; baseline), on postoperative day 1 (T1), and on postoperative day 2 (T2); anesthetic technique; surgery duration; postoperative complications; and postoperative 1-year mortality. Results: In total, 41 patients were included, of which 14 (34.1%) were men and 27 (65.9%) were women; the mean age was 77.8±7.89 (range, 65–95) years. The baseline neutrophil-to-lymphocyte ratio (T0) was 6.22±3.8 increased to 10.66±11.47 on T1 and 8.75±7.81 on T2. neutrophil-to-lymphocyte ratio on T2 was significantly higher in patients receiving general anesthesia than in those receiving spinal anesthesia (p=0.032). Within 1 year after surgery, seven (30.6%) deaths were reported: One patient who received spinal-epidural anesthesia and 6 patients who received general anesthesia (p=0.044). The area under the curve for neutrophil-to-lymphocyte ratio on T2 was 0.79 (95% CI, 0.625–0.955; p=0.017) with an optimal cutoff value of 5.18. Conclusion: Neutrophil-to-lymphocyte ratio on T2 is a risk factor for 1-year mortality in elderly patients with coronary artery disease who underwent hip replacement surgery. Spinal anesthesia was observed to be associated with a lower mortality rate by minimizing neutrophil-to-lymphocyte ratio value on T2 than general anesthesia.