Abstract: Objective To analyze the clinical features and treatment in ADR cases of protamine after cardiopulmonary bypass in children, in order to provide a reference for clinical safe medication. Methods 28 ADR cases of protamine after cardiopulmonary bypass in children with age, sex, dose, route of administration, clinical manifestations of adverse reactions, adverse reaction time, the management of adverse reaction, effect of ultrafiltration on incidence of adverse reaction were analyzed retrospectively. Results 28 patients were caused hypotension after protamine injection. After emergency treatment, 27 cases returned to normal blood pressure, while 1 patient got better in 30min cardiopulmonary bypass rebuilt, no clinical death happened. The incidence of adverse reactions of protamine with ultrafiltration was lower than no ultrafiltration(P=0). Conclusion Protamine may cause severe ADR after cardiopulmonary bypass in children. Ultrafiltration may be the key to lower the incidence of severe ADR.

Key words: protamine, cardiopulmonary bypass, ultrafiltration, combined with heparin