Relationship between protamine dosage for reversing heparin effects in cardiopulmonary bypass surgery and hemostatic and metabolic outcomes

Introduction: Systemic anticoagulation during CPB is achieved with heparin and reversed with protamine, though practices vary. This study examined the impact of two protamine dosing strategies on clinical outcomes. Methods: This retrospective study included 653 patients who met the inclusion criteria and underwent cardiac surgery with cardiopulmonary bypass. Patients who received 0.6 mg protamine for every 100 units of heparin were defined as Group 1, and patients who received 1.2 mg protamine for every 100 units of heparin were defined as Group 2. Descriptive data, preoperative and postoperative variables of the patients were evaluated. Results: Demographic and descriptive data were similar between groups (p>0.05). The only clinically significant difference between groups was the length of hospital stay (p=0.003). Metabolic data showed that urea and lactate levels were higher in group 1 (p=0.012 and p0.05). Conclusion: Both doses were associated with comparable bleeding and transfusion requirements. However, in our study, the length of hospital stay was longer in the group with the 0.6 mg/100IU heparin ratio. Additionally, postoperative urea and lactate levels were also significantly higher in this group.