Morphological changes in erythrocytes in patients undergoing cardiac surgery with cardiopulmonary bypass

ABSTRACT Background: Cardiopulmonary bypass (CPB) is associated with significant hematological alterations due to mechanical stress, hemodilution, and systemic inflammation. Monitoring erythrocyte indices can help predict postoperative recovery and transfusion needs. Objective: The study aims to assess and compare perioperative changes in erythrocyte morphology and hematological parameters among patients undergoing cardiac surgery with CPB using two different blood management strategies. Materials and Methods: A prospective observational study was conducted in 26 patients undergoing elective cardiac surgery with CPB. Patients were divided into two groups ( n = 13 each): Group A received conventional CPB management without additional erythrocyte protection strategies. Group B underwent CPB with integrated erythrocyte preservation interventions (e.g., minimized hemodilution and ultrafiltration). Red blood cell (RBC) indices – hemoglobin (Hb), hematocrit, RBC count, mean corpuscular volume, mean corpuscular Hb (MCH), MCH concentration, and red cell distribution width (RDW) – were measured preoperatively, at CPB weaning, and 24 h postoperatively. Results: In Group A, Hb dropped from 13.52 ± 1.23 to 10.24 ± 0.96 (weaning) and 10.62 ± 1.12 g/dL (24 h); RDW increased from 12.62% ± 1.11% to 16.14% ± 1.37% (weaning) and 15.9% ± 1.25% ( P < 0.001). In Group B, Hb declined from 13.36 ± 1.28 to 11.64 ± 1.12 and 11.88 ± 1.07; RDW rose from 12.58% ± 1.24% to 13.72% ± 1.43% ( P < 0.05), suggesting milder hematologic changes. Conclusion: CPB significantly affects erythrocyte morphology and hematologic indices, with more pronounced changes in patients without protective interventions. Monitoring these parameters can guide perioperative management.