Controlled cardiotomy suction during clinical bubble oxygenator perfusions

Cardiotomy suction causes platelet damage and hemolysis due to air aspiration along with blood suction (uncontrolled suction = US). However, prevention of air aspiration (controlled suction = CS) reduces platelet damage and hemolysis and improves postoperative hemostasis, as only attainable in membrane oxygenator (MO) perfusions. We therefore studied 3 groups of patients subjected to extracorporeal circulation: bubble oxygenator (BO) with CS (n = 10), BO with US (n = 8) and MO with US (n = 10). If CS was used during BO perfusions we found that only hemolysis was significantly reduced, if compared to BO perfusions with US. Despite the use of CS during BO perfusions, platelets were still significantly better preserved during MO perfusions in which US was used. This was indicated by a higher platelet number, higher ADP-induced platelet aggregation, and lower beta-thromboglobulin plasma concentration, during and immediately after MO perfusions. Blood loss and blood transfusions during the first 18 hours after perfusion were not significantly different between the 3 groups. We conclude that the platelet-preserving capacity of CS is completely lost by the platelet damaging effect of the BO. However, reduction in hemolysis is well maintained.