INS and diabetes mellitus: The protamine can be infused via peripheral venous, central venous and aorta, there was minimize change of ABP via aorta, and there was no significant difference of PAP change between the infusion sites.[14,15] DM is risk factor of adverse hemodynamic reaction of protamine following cardiopulmonary bypass.[16] In DM patients who were treated with insulin, there was delayed-type hypersensitivity to protamine.[17] Previous studies showed that the allergic shock and death[18] and anaphylactoid reaction to protamine[19] during open heart surgery were both occurred in DM patients.