Previous studies have shown that Buckberg microplegia reduces the need for intraoperative blood transfusion by minimizing hemodilution. However, this approach has been largely understudied in the context of Del Nido cardioplegia. We hypothesized that applying microplegia principles to Del Nido cardioplegia would similarly reduce transfusion requirements.

A total of 192 consecutive patients undergoing isolated coronary artery bypass grafting with a single crossclamp and 1 dose of cardioplegia at a single institution between October 2023 and January 2025 were divided into 2 groups: standard Del Nido cardioplegia and modified micro Del Nido cardioplegia. All patients underwent retrograde autologous priming before initiation of bypass. Demographic factors, hematocrit levels, lactate levels, bypass time, crossclamp time, and transfusion of blood products including red blood cells, fresh-frozen plasma, platelets, and cryoprecipitate were compared. Additional outcomes of postoperative complications were measured.

Patients receiving modified micro Del Nido cardioplegia received significantly fewer units of intraoperative packed red blood cells (P = .0010), platelets (P = .0429), cryoprecipitate (P = .0149), and total intraoperative blood products (P = .0079) compared with patients receiving Del Nido cardioplegia. Postoperatively, patients receiving modified micro Del Nido cardioplegia also required significantly fewer units of platelets (P = .0387) and cryoprecipitate (P = .0099). Overall, patients receiving modified micro Del Nido cardioplegia received significantly lower total blood products (P = .0001), total platelets (P = .0136), and total cryoprecipitate (P = .0005) throughout hospitalization. They also experienced a smaller decrease in hematocrit (P = .004). No differences were observed in other clinical outcomes or in total red blood cell transfusions (P = .165).

Modified micro Del Nido cardioplegia reduces intraoperative and total blood product use and may further improve outcomes in larger studies.