Factors Influencing Blood Transfusion Requirements in Robotic Totally Endoscopic Coronary Artery Bypass Grafting on the Arrested Heart

Objective: Robotic technology enables totally endoscopic coronary artery bypass grafting (TECAB) procedures. These operations can be performed on either the beating or arrested heart. One challenge of the latter version is a potentially increased need for blood transfusions. We investigated factors associated with transfusion requirements in totally endoscopic coronary artery bypass on the arrested heart (AH-TECAB).

Patients and methods: A total of 161 patients, 124 males and 37 females, aged 59 (31-77 years) years, with European System for Cardiac Operative Risk Evaluation (EuroSCORE) 1 (0-7) underwent AH-TECAB using the daVinci telemanipulation system. The Heartport/Cardiovations or ESTECH-RAP systems were applied for remote access perfusion and aortic endoocclusion. In all cases, the operation was carried out in moderate hypothermia and cardiac arrest using cold crystalloid cardioplegia mixed with blood.

Results: After 20 cases, the blood-transfusion rate dropped from 69% to 44%. The overall median number of transfusions was 1 (0-21). The following pre- and intra-operative factors showed a strong association with the application of packed red blood cells (PRBCs): preoperative haemoglobin level (p<0.001), female gender (p<0.001), shorter height (p<0.001), lower weight (p<0.001), long operative time (p<0.001) and long cardiopulmonary bypass time (p=0.001), intra-operative surgical problem (p<0.001) and conversion to a larger thoracic incision (p<0.001). Postoperatively, patients with longer ventilation time (p<0.001) and those needing revision for bleeding (p<0.001) also received significantly more PRBCs.

Conclusion: We conclude that multiple factors are associated with increased blood transfusion requirements in AH-TECAB. However, the transfusion rate can be reduced with experience. Identification of these factors may help in avoiding the application of blood products in the next generation of AH-TECAB procedures.