The effeckts of acute normovolemic hemodilution on cerebral oxygenation and postoperative neurologic complications in coronary artery disease patients undergoing open heart surgery

SUMMARY Introduction and Goal: In this study, we aimed to evaluate the effects of acute normovolemic hemodilution (ANH) on tissue oxygenation (rSO2) and neurological complications with near infrared spectrometry (NIRS). Materials and Methods:100 patients were prospectively included in the study.Patients receiving acute normovolemic hemodilution were divided into two groups according to the hematocrit (Hct) value at the cardiopulmonary bypass entrance.Group 1 included 43 patients with an Htc value of less than 24%, and Group 2 included 57 patients with an Htc value of 24% or greater.Preoperative, intraoperative and postoperative values, inotrop and blood usage, complications, rSO2 values ​​of both groups were compared with NIRS. Finding:The mean age of the patients was 59.23 ± 8.45 years and only 5 patients (5%) were female.The amount of ANH was greater in group 2 than in group 1 (586 mL vs. 495 mL, p = 0.005).In Group 2, the hematocrit value was higher and rSO2 values ​​were higher.Blood product use and complications were similar in both groups (p ˃ 0.05).The mean rSO2 value of patients with neurological complications was similar at all times compared to those with no development (p = 0.023).In patients with complications, the mean rSO2 value was lower (p = 0.006) at the end of the operation and TDP was higher in the first 24 hours (p = 0.008). Result: The use of NIRS in the monitoring of acute normovolemic hemodilution in coronary artery bypass grafting is a reliable method and has not been able to reduce blood product use, inotropic use and complications (24% above hemodocrit value during CPB).