Post-operative protamine infusion does not lead to reduced bleeding or
transfusion following coronary artery bypass grafting
Abstract
Aim: Post-operative bleeding remains a significant risk after
cardiac surgery. Despite adequate protamine reversal of heparin
intraoperatively, protein-bound heparin causes anticoagulant effect,
leading to bleeding in the post-operative period. The aim of this study
is to whether the use of a four-hour, low dose protamine infusion in
intensive care would reduce post-operative bleeding and hence, blood
transfusion requirements. Methods: A retrospective cohort study
of seven hundred and two patients, who underwent elective or urgent
coronary artery bypass grafting from April 2014 and January 2017, were
divided into two groups based on who received post-operative protamine
infusion (Group A, 472 patients) versus those who did not (Group B, 230
patients). They were assessed for amount of post-operative mediastinal
and pleural drainage for the first 24 hours, use of post-operative
transfusion of blood products, postoperative hospital stay, and
re-exploration. Results: We found no significant difference
between the rate of bleeding in either of the groups. No significant
difference was observed in blood product requirements as well. In the
sub-group consisting of patients with high BMI (BMI ≥30), who received
protamine infusion, post-operative platelets transfusion was found to be
significantly less. Conclusions: Our results suggest that a low
dose protamine infusion given in the immediate postoperative period does
not lead to any significant clinical benefits. Both patients receiving
and not receiving the infusion had similar postoperative drainage,
transfusion requirements, haemorrhagic morbidity, mortality and length
of hospital stay.