Risk Factors Associated with Difficult Reversal of Heparin by Protamine Sulfate in Cardiopulmonary Bypass: An Ignored...

The aim of this study was to evaluate risk factors associated with difficult heparin reversal by protamine after cardiopulmonary bypass.

Data from 120 consecutive patients who underwent open heart surgery from 2009 to 2017 were retrospectively reviewed. Patients were divided into 2 groups: (1) those in whom complete heparin reversal was achieved after a single infusion of protamine (group A, n=89); and (2) those who required more protamine for heparin reversal (group B, n=31).

Female sex, prolonged bypass time (>200 min), long aortic cross-clamping time (>120 min), and a lowest rectal temperature <26°C were significant predictors of difficult heparin reversal. Larger amounts of fresh frozen plasma and platelet concentrate were transfused in group B than in group A.

Surgeons' efforts to reduce operative time and avoid deep hypothermia may be helpful for increasing the likelihood of easy heparin reversal, especially in female patients.