Processed Residual Pump Blood in Cardiac Surgery: The PRBC Trial (PRBC)

The study is an randomized controlled trial (RCT) of 198 coronary artery bypass graft (CABG) patients, exploring whether ultrafiltration of residual blood in the cardiopulmonary bypass circuit reduces transfusion and bleeding.

Blood products are a limited resource and cardiac surgery is a high consumer. Processing residual cardiopulmonary bypass (CPB) volume via ultrafiltration may improve hemostasis and reduce transfusion through clearing activated complement, activated coagulation components, and proinflammatory cytokines. Unlike cell saver technology, ultrafiltration has the advantage of maintaining plasma proteins, platelets, and coagulation factors. We sought to establish if the processing of residual CPB volume with ultrafiltration reduces homologous blood transfusion and bleeding.

The current practice in our institution was to displace all the remaining volume in the CPB circuit into a transfer pack by displacing the remaining blood in the CPB circuit with additional Lactated Ringers solution. This transfer pack is then given to the anesthetist for reinfusion into the patient.

The inflow line to the hemoconcentrator was connected to the sideport of the arterial filter stopcock, allowing the residual blood in the CPB circuit to be processed through the hemoconcentrator. The outflow line from the hemoconcentrator was connected to a second three way stopcock located on the cardiotomy reservoir. Blood was circulated from the venous reservoir through the hemoconcentrator and returned to the venous reservoir until the desired hematocrit was achieved. The blood was then diverted to a transfer pack until all the blood from the venous reservoir, heat exchanger, and membrane oxygenator had been filtered and hemoconcentrated. This transfer pack was given to the anesthetist for reinfusion into the patient.

Inclusion Criteria: at least 18 years of age were to undergo isolated on-pump CABG were able to give informed consent Exclusion Criteria: performed autologous blood donation underwent off-pump CABG emergency procedure resternotomy known bleeding disorder not drug related history of heparin-induced thrombocytopenia Jehovah's Witness intra-operative catastrophe prior to randomization

Whitlock R, Mathew J, Eikelboom J, Al-Saleh AM, Yuan F, Teoh K. Processed residual pump blood in cardiac surgery: the Processed Residual Blood in Cardiac surgery trial. Transfusion. 2013 Jul;53(7):1487-92. doi: 10.1111/j.1537-2995.2012.03958.x. Epub 2012 Nov 26.