Preoperative point-of-care platelet function testing in cardiac surgery

Abstract

Objective: To investigate if the use of preoperative platelet function testing (PFT) as part of a transfusion algorithm reduced blood product usage in coronary artery bypass surgery (CABG).

Design: Prospective, randomized, controlled trial.

Setting: A cardiothoracic hospital.

Participants: 249 patients having CABG surgery.

Interventions: The patients were allocated randomly to PFT preoperatively with Multiple Electrode Aggregometry (MEA, Group A), TEG PlateletMapping (PM, Group B) or none (control, Group C). Post-bypass bleeding management was determined by a transfusion algorithm.

Measurements and main results: The primary outcome measure was blood product transfusion in the first 48 hours post-surgery. There was a significant reduction in all blood product transfusion between Groups A (MEA) and B (PM) and Group C (control) (median number of units transfused, 2 (A)/2 (B)/ 4(C), p=0.02). Those in A and B received fewer units of red cells (median number of units, 0 (A)/1 (B) /2 (C), p=0.006) and fresh frozen plasma than the control Group C (median number of units, 0 (A)/0 (B)/2 (C), p<0.001), without receiving significantly more units of platelets (median number of units, 1 (A)/1 (B)/0 (C), p=0.11). In those who had taken an adenosine disphosphate (ADP)-receptor antagonist within 5 days (n=173), these results were amplified, and additionally, there was a significant cost saving (median cost, A=£1738.53, B=£1736.96, C=£3191.80 p=0.006).

Conclusion: Preoperative PFT as part of a point-of-care testing-based transfusion algorithm led to a reduction in blood transfusion. There is a potential cost saving in those who have taken an ADP-receptor antagonist within 5 days.

Keywords: ADP-receptor antagonist; CABG; antiplatelet therapy; multiple electrode aggregometry; platelet mapping; point-of-care technology; transfusion.