Vacuum-assisted venous drainage in single-access minimally invasive cardiac surgery

This retrospective study evaluated the influence of vacuum-assisted venous drainage in single-access minimally invasive cardiac surgery. A total of 104 patients who underwent cardiac surgery via minimal access incision were included in this study. Cardiopulmonary bypass was initiated with gravity alone, and vacuum-assisted venous drainage was applied only when the bypass flow was 2.2 l/min/m2 or less. We compared intraoperative variables of the patients to whom vacuum-assisted venous drainage (vacuum group) was applied with those who underwent gravity venous drainage alone (gravity group). In the 13 patients who most recently underwent isolated valve operations without maze procedures, free hemoglobin was measured to evaluate hemolysis. Vacuum-assisted venous drainage was required in 77 (72.6%) patients. Except for a smaller body surface area in the gravity group (P = 0.0118), patient characteristics did not differ significantly between the two groups. Free hemoglobin 60 mins after the beginning of cardiopulmonary bypass was higher in the vacuum group than in the gravity group (21.5 +/- 7.3 vs 11.1 +/- 7.1 mg/dl, P = 0.0284). Operative mortality and morbidity did not differ significantly between the groups. We found vacuum-assisted venous drainage to be a safe, simple, and effective technique in cases of minimally invasive cardiac surgery. However, there is a potential risk of hemolysis and air embolism, as shown in our findings and previous reports.