Discussion
Limitations including: single-center, unblinded study design, and retrospective chart review make it prohibitive to perform robust data analysis. It is difficult to discern true benefit compared to available meta-analysis data, which predominantly compares PCC4 to blood product administration after this surgical population is already bleeding postoperatively .6
Transfusion rates and amount of individual blood products compare favorably to available literature, including compared to the meta-analysis’ data trending toward less products used ((overall FFP rate of 0 (IQR 0-3 units) compared to available literature 3-14 units)).5,6,7 Further, chest tube output was lower than generally expected as described in the literature for this surgical population (overall output of 757 ml compared to 935ml +/- 583).7 Comparable incidence of volume overload driven right ventricular failure and acute kidney injury were low when reviewing the current literature, where AKI has been described as potentially more likely post PCC4 dosing in this surgical population.6,8,9 Our findings did not support the notion of this kidney injury risk, albeit a smaller sample size. To concretize the intervention and its potential benefit, this analysis at minimum establishes an intermediate weight based PCC4 dose, operative timing, and consideration for PCC4 where it is believed the data presented is favorable for the use in select patients undergoing high risk cardiac surgery, and perhaps more specifically, those patients undergoing aortic dissection, LVAD placement, or heart transplant.
From a cost to provide intervention perspective, PCC4 costs approximately $1.81 per unit. Therefore, a dose of approximately 3,000 units costs $5450 per dose. Comparatively, the acquisition cost at our institution to provide a single unit of fresh frozen plasma is $ 200, packed red blood cells $ 196, platelets $ 634, and cryoprecipitate $ 475 for one pooled bag of five units. The cost of intensive care management for a transfusion-dependent postoperative patient is substantial, and for the purposes of this review, is too challenging to quantitatively describe; although, the cost avoidance of such complications would seem significant. From this data it is reasonable to suggest that providing a single dose of PCC4 intraoperatively after protamine at minimum may positively impact critical blood product supply, and even more so offset the cost of blood product administration and its deleterious clinical consequences. Compared to available individual trial and meta-analysis data, the patients in our sample had less blood transfusion, decreased postoperative chest tube site bleeding, no increase in acute kidney injury or occlusive disease, and a low incidence of right ventricular dysfunction. Specifically, the cost-benefit to the patient by principally avoiding transfusion related acute lung injury, volume associated right ventricular dysfunction, additional intensive care unit time and ultimately, the associated increase in intensive care complications - may be where the patient most benefits. The use of intraoperative PCC4 timed to be given immediately after protamine may decrease bleeding complications, right heart failure, and the unfavorable collateral damage associated with blood product transfusion. Further large randomized controlled trials are recommended.