Bloodless and non-inotropic cardiac surgery under closed-circuit anesthesia

The safety of homologous blood transfusion has become a major concern for patients and physicians. Current transfusion practice is highly variable and may be associated with inappropriate blood use. Inotropic agents have been almost routinely administered perioperatively to patients undergoing cardiac surgery to overcome low cardiac output due to cardiopulmonary bypass (CPB) and cardioplegia-induced cardiac ischemic arrest. In this study, we evaluated the feasibility of bloodless and non-inotropic open-heart surgery.

Perioperative clinical data were retrospectively collected from two groups of patients undergoing open-heart surgery by one surgeon in the same season. Twenty consecutive patients underwent a bloodless approach and received isoflurane-based closed-circuit general anesthesia and 20 consecutive patients (comparison group) underwent fentanyl-based anesthesia. A cell-saver was used for all patients to collect the CPB circuit blood for retransfusion. In the comparison group, conventional criteria were applied for blood transfusion and inotropic support and the goal was to keep hemoglobin > 10 g/dL and cardiac index > 2.2 L/min/m(2). In the bloodless group, new criteria for blood transfusion and inotropic support were used and included (1) low cardiac output syndrome, (2) impaired hemodynamic status and mixed venous oxygen saturation, (3) inadequate urine output, (4) metabolic acidosis, (5) ischemic signs on electrocardiography, and (6) patient's autonomy after being informed of and discussing the benefits and risks of blood transfusion.

In both groups, there was no in-hospital mortality and all patients were discharged in a stable condition. Eighteen of 20 (90%) patients did not receive blood transfusion, while inotropic support was not provided in 17 of 20 (85%) patients in the bloodless group; in contrast, blood transfusion and inotropic support were required for all patients in the comparison group (both: p<0.01). All patients in the bloodless group, except one with severe chronic obstructive pulmonary disease (1-second forced expiratory volume of 0.9 L), accomplished earlier extubation (mean+/-standard deviation, 1.2+/-1.1 hours) and shorter intensive care unit stay (3.1+/-2.1 days), as compared with patients in the comparison group (19.5+/-2.5 hours and 5.1+/-1.7 days, respectively; both: p<0.01). Systemic vascular resistance was significantly lower in the bloodless group.

In conclusion, bloodless and non-inotropic cardiac surgery is feasible with the aid of a cell-saver and closed-circuit anesthesia in combination with new practice guidelines.